Subversion Repositories Kolibri OS

Rev

Go to most recent revision | Blame | Last modification | View Log | RSS feed

  1. /*
  2.  * copyright (c) 2001 Fabrice Bellard
  3.  *
  4.  * This file is part of FFmpeg.
  5.  *
  6.  * FFmpeg is free software; you can redistribute it and/or
  7.  * modify it under the terms of the GNU Lesser General Public
  8.  * License as published by the Free Software Foundation; either
  9.  * version 2.1 of the License, or (at your option) any later version.
  10.  *
  11.  * FFmpeg is distributed in the hope that it will be useful,
  12.  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14.  * Lesser General Public License for more details.
  15.  *
  16.  * You should have received a copy of the GNU Lesser General Public
  17.  * License along with FFmpeg; if not, write to the Free Software
  18.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19.  */
  20.  
  21. #ifndef AVCODEC_AVCODEC_H
  22. #define AVCODEC_AVCODEC_H
  23.  
  24. /**
  25.  * @file
  26.  * @ingroup libavc
  27.  * Libavcodec external API header
  28.  */
  29.  
  30. #include <errno.h>
  31. #include "libavutil/samplefmt.h"
  32. #include "libavutil/attributes.h"
  33. #include "libavutil/avutil.h"
  34. #include "libavutil/buffer.h"
  35. #include "libavutil/cpu.h"
  36. #include "libavutil/channel_layout.h"
  37. #include "libavutil/dict.h"
  38. #include "libavutil/frame.h"
  39. #include "libavutil/log.h"
  40. #include "libavutil/pixfmt.h"
  41. #include "libavutil/rational.h"
  42.  
  43. #include "version.h"
  44.  
  45. /**
  46.  * @defgroup libavc Encoding/Decoding Library
  47.  * @{
  48.  *
  49.  * @defgroup lavc_decoding Decoding
  50.  * @{
  51.  * @}
  52.  *
  53.  * @defgroup lavc_encoding Encoding
  54.  * @{
  55.  * @}
  56.  *
  57.  * @defgroup lavc_codec Codecs
  58.  * @{
  59.  * @defgroup lavc_codec_native Native Codecs
  60.  * @{
  61.  * @}
  62.  * @defgroup lavc_codec_wrappers External library wrappers
  63.  * @{
  64.  * @}
  65.  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
  66.  * @{
  67.  * @}
  68.  * @}
  69.  * @defgroup lavc_internal Internal
  70.  * @{
  71.  * @}
  72.  * @}
  73.  *
  74.  */
  75.  
  76. /**
  77.  * @defgroup lavc_core Core functions/structures.
  78.  * @ingroup libavc
  79.  *
  80.  * Basic definitions, functions for querying libavcodec capabilities,
  81.  * allocating core structures, etc.
  82.  * @{
  83.  */
  84.  
  85.  
  86. /**
  87.  * Identify the syntax and semantics of the bitstream.
  88.  * The principle is roughly:
  89.  * Two decoders with the same ID can decode the same streams.
  90.  * Two encoders with the same ID can encode compatible streams.
  91.  * There may be slight deviations from the principle due to implementation
  92.  * details.
  93.  *
  94.  * If you add a codec ID to this list, add it so that
  95.  * 1. no value of a existing codec ID changes (that would break ABI),
  96.  * 2. Give it a value which when taken as ASCII is recognized uniquely by a human as this specific codec.
  97.  *    This ensures that 2 forks can independently add AVCodecIDs without producing conflicts.
  98.  *
  99.  * After adding new codec IDs, do not forget to add an entry to the codec
  100.  * descriptor list and bump libavcodec minor version.
  101.  */
  102. enum AVCodecID {
  103.     AV_CODEC_ID_NONE,
  104.  
  105.     /* video codecs */
  106.     AV_CODEC_ID_MPEG1VIDEO,
  107.     AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
  108.     AV_CODEC_ID_MPEG2VIDEO_XVMC,
  109.     AV_CODEC_ID_H261,
  110.     AV_CODEC_ID_H263,
  111.     AV_CODEC_ID_RV10,
  112.     AV_CODEC_ID_RV20,
  113.     AV_CODEC_ID_MJPEG,
  114.     AV_CODEC_ID_MJPEGB,
  115.     AV_CODEC_ID_LJPEG,
  116.     AV_CODEC_ID_SP5X,
  117.     AV_CODEC_ID_JPEGLS,
  118.     AV_CODEC_ID_MPEG4,
  119.     AV_CODEC_ID_RAWVIDEO,
  120.     AV_CODEC_ID_MSMPEG4V1,
  121.     AV_CODEC_ID_MSMPEG4V2,
  122.     AV_CODEC_ID_MSMPEG4V3,
  123.     AV_CODEC_ID_WMV1,
  124.     AV_CODEC_ID_WMV2,
  125.     AV_CODEC_ID_H263P,
  126.     AV_CODEC_ID_H263I,
  127.     AV_CODEC_ID_FLV1,
  128.     AV_CODEC_ID_SVQ1,
  129.     AV_CODEC_ID_SVQ3,
  130.     AV_CODEC_ID_DVVIDEO,
  131.     AV_CODEC_ID_HUFFYUV,
  132.     AV_CODEC_ID_CYUV,
  133.     AV_CODEC_ID_H264,
  134.     AV_CODEC_ID_INDEO3,
  135.     AV_CODEC_ID_VP3,
  136.     AV_CODEC_ID_THEORA,
  137.     AV_CODEC_ID_ASV1,
  138.     AV_CODEC_ID_ASV2,
  139.     AV_CODEC_ID_FFV1,
  140.     AV_CODEC_ID_4XM,
  141.     AV_CODEC_ID_VCR1,
  142.     AV_CODEC_ID_CLJR,
  143.     AV_CODEC_ID_MDEC,
  144.     AV_CODEC_ID_ROQ,
  145.     AV_CODEC_ID_INTERPLAY_VIDEO,
  146.     AV_CODEC_ID_XAN_WC3,
  147.     AV_CODEC_ID_XAN_WC4,
  148.     AV_CODEC_ID_RPZA,
  149.     AV_CODEC_ID_CINEPAK,
  150.     AV_CODEC_ID_WS_VQA,
  151.     AV_CODEC_ID_MSRLE,
  152.     AV_CODEC_ID_MSVIDEO1,
  153.     AV_CODEC_ID_IDCIN,
  154.     AV_CODEC_ID_8BPS,
  155.     AV_CODEC_ID_SMC,
  156.     AV_CODEC_ID_FLIC,
  157.     AV_CODEC_ID_TRUEMOTION1,
  158.     AV_CODEC_ID_VMDVIDEO,
  159.     AV_CODEC_ID_MSZH,
  160.     AV_CODEC_ID_ZLIB,
  161.     AV_CODEC_ID_QTRLE,
  162.     AV_CODEC_ID_TSCC,
  163.     AV_CODEC_ID_ULTI,
  164.     AV_CODEC_ID_QDRAW,
  165.     AV_CODEC_ID_VIXL,
  166.     AV_CODEC_ID_QPEG,
  167.     AV_CODEC_ID_PNG,
  168.     AV_CODEC_ID_PPM,
  169.     AV_CODEC_ID_PBM,
  170.     AV_CODEC_ID_PGM,
  171.     AV_CODEC_ID_PGMYUV,
  172.     AV_CODEC_ID_PAM,
  173.     AV_CODEC_ID_FFVHUFF,
  174.     AV_CODEC_ID_RV30,
  175.     AV_CODEC_ID_RV40,
  176.     AV_CODEC_ID_VC1,
  177.     AV_CODEC_ID_WMV3,
  178.     AV_CODEC_ID_LOCO,
  179.     AV_CODEC_ID_WNV1,
  180.     AV_CODEC_ID_AASC,
  181.     AV_CODEC_ID_INDEO2,
  182.     AV_CODEC_ID_FRAPS,
  183.     AV_CODEC_ID_TRUEMOTION2,
  184.     AV_CODEC_ID_BMP,
  185.     AV_CODEC_ID_CSCD,
  186.     AV_CODEC_ID_MMVIDEO,
  187.     AV_CODEC_ID_ZMBV,
  188.     AV_CODEC_ID_AVS,
  189.     AV_CODEC_ID_SMACKVIDEO,
  190.     AV_CODEC_ID_NUV,
  191.     AV_CODEC_ID_KMVC,
  192.     AV_CODEC_ID_FLASHSV,
  193.     AV_CODEC_ID_CAVS,
  194.     AV_CODEC_ID_JPEG2000,
  195.     AV_CODEC_ID_VMNC,
  196.     AV_CODEC_ID_VP5,
  197.     AV_CODEC_ID_VP6,
  198.     AV_CODEC_ID_VP6F,
  199.     AV_CODEC_ID_TARGA,
  200.     AV_CODEC_ID_DSICINVIDEO,
  201.     AV_CODEC_ID_TIERTEXSEQVIDEO,
  202.     AV_CODEC_ID_TIFF,
  203.     AV_CODEC_ID_GIF,
  204.     AV_CODEC_ID_DXA,
  205.     AV_CODEC_ID_DNXHD,
  206.     AV_CODEC_ID_THP,
  207.     AV_CODEC_ID_SGI,
  208.     AV_CODEC_ID_C93,
  209.     AV_CODEC_ID_BETHSOFTVID,
  210.     AV_CODEC_ID_PTX,
  211.     AV_CODEC_ID_TXD,
  212.     AV_CODEC_ID_VP6A,
  213.     AV_CODEC_ID_AMV,
  214.     AV_CODEC_ID_VB,
  215.     AV_CODEC_ID_PCX,
  216.     AV_CODEC_ID_SUNRAST,
  217.     AV_CODEC_ID_INDEO4,
  218.     AV_CODEC_ID_INDEO5,
  219.     AV_CODEC_ID_MIMIC,
  220.     AV_CODEC_ID_RL2,
  221.     AV_CODEC_ID_ESCAPE124,
  222.     AV_CODEC_ID_DIRAC,
  223.     AV_CODEC_ID_BFI,
  224.     AV_CODEC_ID_CMV,
  225.     AV_CODEC_ID_MOTIONPIXELS,
  226.     AV_CODEC_ID_TGV,
  227.     AV_CODEC_ID_TGQ,
  228.     AV_CODEC_ID_TQI,
  229.     AV_CODEC_ID_AURA,
  230.     AV_CODEC_ID_AURA2,
  231.     AV_CODEC_ID_V210X,
  232.     AV_CODEC_ID_TMV,
  233.     AV_CODEC_ID_V210,
  234.     AV_CODEC_ID_DPX,
  235.     AV_CODEC_ID_MAD,
  236.     AV_CODEC_ID_FRWU,
  237.     AV_CODEC_ID_FLASHSV2,
  238.     AV_CODEC_ID_CDGRAPHICS,
  239.     AV_CODEC_ID_R210,
  240.     AV_CODEC_ID_ANM,
  241.     AV_CODEC_ID_BINKVIDEO,
  242.     AV_CODEC_ID_IFF_ILBM,
  243.     AV_CODEC_ID_IFF_BYTERUN1,
  244.     AV_CODEC_ID_KGV1,
  245.     AV_CODEC_ID_YOP,
  246.     AV_CODEC_ID_VP8,
  247.     AV_CODEC_ID_PICTOR,
  248.     AV_CODEC_ID_ANSI,
  249.     AV_CODEC_ID_A64_MULTI,
  250.     AV_CODEC_ID_A64_MULTI5,
  251.     AV_CODEC_ID_R10K,
  252.     AV_CODEC_ID_MXPEG,
  253.     AV_CODEC_ID_LAGARITH,
  254.     AV_CODEC_ID_PRORES,
  255.     AV_CODEC_ID_JV,
  256.     AV_CODEC_ID_DFA,
  257.     AV_CODEC_ID_WMV3IMAGE,
  258.     AV_CODEC_ID_VC1IMAGE,
  259.     AV_CODEC_ID_UTVIDEO,
  260.     AV_CODEC_ID_BMV_VIDEO,
  261.     AV_CODEC_ID_VBLE,
  262.     AV_CODEC_ID_DXTORY,
  263.     AV_CODEC_ID_V410,
  264.     AV_CODEC_ID_XWD,
  265.     AV_CODEC_ID_CDXL,
  266.     AV_CODEC_ID_XBM,
  267.     AV_CODEC_ID_ZEROCODEC,
  268.     AV_CODEC_ID_MSS1,
  269.     AV_CODEC_ID_MSA1,
  270.     AV_CODEC_ID_TSCC2,
  271.     AV_CODEC_ID_MTS2,
  272.     AV_CODEC_ID_CLLC,
  273.     AV_CODEC_ID_MSS2,
  274.     AV_CODEC_ID_VP9,
  275.     AV_CODEC_ID_AIC,
  276.     AV_CODEC_ID_ESCAPE130_DEPRECATED,
  277.     AV_CODEC_ID_G2M_DEPRECATED,
  278.     AV_CODEC_ID_WEBP_DEPRECATED,
  279.  
  280.     AV_CODEC_ID_BRENDER_PIX= MKBETAG('B','P','I','X'),
  281.     AV_CODEC_ID_Y41P       = MKBETAG('Y','4','1','P'),
  282.     AV_CODEC_ID_ESCAPE130  = MKBETAG('E','1','3','0'),
  283.     AV_CODEC_ID_EXR        = MKBETAG('0','E','X','R'),
  284.     AV_CODEC_ID_AVRP       = MKBETAG('A','V','R','P'),
  285.  
  286.     AV_CODEC_ID_012V       = MKBETAG('0','1','2','V'),
  287.     AV_CODEC_ID_G2M        = MKBETAG( 0 ,'G','2','M'),
  288.     AV_CODEC_ID_AVUI       = MKBETAG('A','V','U','I'),
  289.     AV_CODEC_ID_AYUV       = MKBETAG('A','Y','U','V'),
  290.     AV_CODEC_ID_TARGA_Y216 = MKBETAG('T','2','1','6'),
  291.     AV_CODEC_ID_V308       = MKBETAG('V','3','0','8'),
  292.     AV_CODEC_ID_V408       = MKBETAG('V','4','0','8'),
  293.     AV_CODEC_ID_YUV4       = MKBETAG('Y','U','V','4'),
  294.     AV_CODEC_ID_SANM       = MKBETAG('S','A','N','M'),
  295.     AV_CODEC_ID_PAF_VIDEO  = MKBETAG('P','A','F','V'),
  296.     AV_CODEC_ID_AVRN       = MKBETAG('A','V','R','n'),
  297.     AV_CODEC_ID_CPIA       = MKBETAG('C','P','I','A'),
  298.     AV_CODEC_ID_XFACE      = MKBETAG('X','F','A','C'),
  299.     AV_CODEC_ID_SGIRLE     = MKBETAG('S','G','I','R'),
  300.     AV_CODEC_ID_MVC1       = MKBETAG('M','V','C','1'),
  301.     AV_CODEC_ID_MVC2       = MKBETAG('M','V','C','2'),
  302.     AV_CODEC_ID_SNOW       = MKBETAG('S','N','O','W'),
  303.     AV_CODEC_ID_WEBP       = MKBETAG('W','E','B','P'),
  304.     AV_CODEC_ID_SMVJPEG    = MKBETAG('S','M','V','J'),
  305.     AV_CODEC_ID_HEVC       = MKBETAG('H','2','6','5'),
  306. #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
  307.  
  308.     /* various PCM "codecs" */
  309.     AV_CODEC_ID_FIRST_AUDIO = 0x10000,     ///< A dummy id pointing at the start of audio codecs
  310.     AV_CODEC_ID_PCM_S16LE = 0x10000,
  311.     AV_CODEC_ID_PCM_S16BE,
  312.     AV_CODEC_ID_PCM_U16LE,
  313.     AV_CODEC_ID_PCM_U16BE,
  314.     AV_CODEC_ID_PCM_S8,
  315.     AV_CODEC_ID_PCM_U8,
  316.     AV_CODEC_ID_PCM_MULAW,
  317.     AV_CODEC_ID_PCM_ALAW,
  318.     AV_CODEC_ID_PCM_S32LE,
  319.     AV_CODEC_ID_PCM_S32BE,
  320.     AV_CODEC_ID_PCM_U32LE,
  321.     AV_CODEC_ID_PCM_U32BE,
  322.     AV_CODEC_ID_PCM_S24LE,
  323.     AV_CODEC_ID_PCM_S24BE,
  324.     AV_CODEC_ID_PCM_U24LE,
  325.     AV_CODEC_ID_PCM_U24BE,
  326.     AV_CODEC_ID_PCM_S24DAUD,
  327.     AV_CODEC_ID_PCM_ZORK,
  328.     AV_CODEC_ID_PCM_S16LE_PLANAR,
  329.     AV_CODEC_ID_PCM_DVD,
  330.     AV_CODEC_ID_PCM_F32BE,
  331.     AV_CODEC_ID_PCM_F32LE,
  332.     AV_CODEC_ID_PCM_F64BE,
  333.     AV_CODEC_ID_PCM_F64LE,
  334.     AV_CODEC_ID_PCM_BLURAY,
  335.     AV_CODEC_ID_PCM_LXF,
  336.     AV_CODEC_ID_S302M,
  337.     AV_CODEC_ID_PCM_S8_PLANAR,
  338.     AV_CODEC_ID_PCM_S24LE_PLANAR_DEPRECATED,
  339.     AV_CODEC_ID_PCM_S32LE_PLANAR_DEPRECATED,
  340.     AV_CODEC_ID_PCM_S24LE_PLANAR = MKBETAG(24,'P','S','P'),
  341.     AV_CODEC_ID_PCM_S32LE_PLANAR = MKBETAG(32,'P','S','P'),
  342.     AV_CODEC_ID_PCM_S16BE_PLANAR = MKBETAG('P','S','P',16),
  343.  
  344.     /* various ADPCM codecs */
  345.     AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
  346.     AV_CODEC_ID_ADPCM_IMA_WAV,
  347.     AV_CODEC_ID_ADPCM_IMA_DK3,
  348.     AV_CODEC_ID_ADPCM_IMA_DK4,
  349.     AV_CODEC_ID_ADPCM_IMA_WS,
  350.     AV_CODEC_ID_ADPCM_IMA_SMJPEG,
  351.     AV_CODEC_ID_ADPCM_MS,
  352.     AV_CODEC_ID_ADPCM_4XM,
  353.     AV_CODEC_ID_ADPCM_XA,
  354.     AV_CODEC_ID_ADPCM_ADX,
  355.     AV_CODEC_ID_ADPCM_EA,
  356.     AV_CODEC_ID_ADPCM_G726,
  357.     AV_CODEC_ID_ADPCM_CT,
  358.     AV_CODEC_ID_ADPCM_SWF,
  359.     AV_CODEC_ID_ADPCM_YAMAHA,
  360.     AV_CODEC_ID_ADPCM_SBPRO_4,
  361.     AV_CODEC_ID_ADPCM_SBPRO_3,
  362.     AV_CODEC_ID_ADPCM_SBPRO_2,
  363.     AV_CODEC_ID_ADPCM_THP,
  364.     AV_CODEC_ID_ADPCM_IMA_AMV,
  365.     AV_CODEC_ID_ADPCM_EA_R1,
  366.     AV_CODEC_ID_ADPCM_EA_R3,
  367.     AV_CODEC_ID_ADPCM_EA_R2,
  368.     AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
  369.     AV_CODEC_ID_ADPCM_IMA_EA_EACS,
  370.     AV_CODEC_ID_ADPCM_EA_XAS,
  371.     AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
  372.     AV_CODEC_ID_ADPCM_IMA_ISS,
  373.     AV_CODEC_ID_ADPCM_G722,
  374.     AV_CODEC_ID_ADPCM_IMA_APC,
  375.     AV_CODEC_ID_VIMA       = MKBETAG('V','I','M','A'),
  376.     AV_CODEC_ID_ADPCM_AFC  = MKBETAG('A','F','C',' '),
  377.     AV_CODEC_ID_ADPCM_IMA_OKI = MKBETAG('O','K','I',' '),
  378.     AV_CODEC_ID_ADPCM_DTK  = MKBETAG('D','T','K',' '),
  379.     AV_CODEC_ID_ADPCM_IMA_RAD = MKBETAG('R','A','D',' '),
  380.     AV_CODEC_ID_ADPCM_G726LE = MKBETAG('6','2','7','G'),
  381.  
  382.     /* AMR */
  383.     AV_CODEC_ID_AMR_NB = 0x12000,
  384.     AV_CODEC_ID_AMR_WB,
  385.  
  386.     /* RealAudio codecs*/
  387.     AV_CODEC_ID_RA_144 = 0x13000,
  388.     AV_CODEC_ID_RA_288,
  389.  
  390.     /* various DPCM codecs */
  391.     AV_CODEC_ID_ROQ_DPCM = 0x14000,
  392.     AV_CODEC_ID_INTERPLAY_DPCM,
  393.     AV_CODEC_ID_XAN_DPCM,
  394.     AV_CODEC_ID_SOL_DPCM,
  395.  
  396.     /* audio codecs */
  397.     AV_CODEC_ID_MP2 = 0x15000,
  398.     AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
  399.     AV_CODEC_ID_AAC,
  400.     AV_CODEC_ID_AC3,
  401.     AV_CODEC_ID_DTS,
  402.     AV_CODEC_ID_VORBIS,
  403.     AV_CODEC_ID_DVAUDIO,
  404.     AV_CODEC_ID_WMAV1,
  405.     AV_CODEC_ID_WMAV2,
  406.     AV_CODEC_ID_MACE3,
  407.     AV_CODEC_ID_MACE6,
  408.     AV_CODEC_ID_VMDAUDIO,
  409.     AV_CODEC_ID_FLAC,
  410.     AV_CODEC_ID_MP3ADU,
  411.     AV_CODEC_ID_MP3ON4,
  412.     AV_CODEC_ID_SHORTEN,
  413.     AV_CODEC_ID_ALAC,
  414.     AV_CODEC_ID_WESTWOOD_SND1,
  415.     AV_CODEC_ID_GSM, ///< as in Berlin toast format
  416.     AV_CODEC_ID_QDM2,
  417.     AV_CODEC_ID_COOK,
  418.     AV_CODEC_ID_TRUESPEECH,
  419.     AV_CODEC_ID_TTA,
  420.     AV_CODEC_ID_SMACKAUDIO,
  421.     AV_CODEC_ID_QCELP,
  422.     AV_CODEC_ID_WAVPACK,
  423.     AV_CODEC_ID_DSICINAUDIO,
  424.     AV_CODEC_ID_IMC,
  425.     AV_CODEC_ID_MUSEPACK7,
  426.     AV_CODEC_ID_MLP,
  427.     AV_CODEC_ID_GSM_MS, /* as found in WAV */
  428.     AV_CODEC_ID_ATRAC3,
  429. #if FF_API_VOXWARE
  430.     AV_CODEC_ID_VOXWARE,
  431. #endif
  432.     AV_CODEC_ID_APE,
  433.     AV_CODEC_ID_NELLYMOSER,
  434.     AV_CODEC_ID_MUSEPACK8,
  435.     AV_CODEC_ID_SPEEX,
  436.     AV_CODEC_ID_WMAVOICE,
  437.     AV_CODEC_ID_WMAPRO,
  438.     AV_CODEC_ID_WMALOSSLESS,
  439.     AV_CODEC_ID_ATRAC3P,
  440.     AV_CODEC_ID_EAC3,
  441.     AV_CODEC_ID_SIPR,
  442.     AV_CODEC_ID_MP1,
  443.     AV_CODEC_ID_TWINVQ,
  444.     AV_CODEC_ID_TRUEHD,
  445.     AV_CODEC_ID_MP4ALS,
  446.     AV_CODEC_ID_ATRAC1,
  447.     AV_CODEC_ID_BINKAUDIO_RDFT,
  448.     AV_CODEC_ID_BINKAUDIO_DCT,
  449.     AV_CODEC_ID_AAC_LATM,
  450.     AV_CODEC_ID_QDMC,
  451.     AV_CODEC_ID_CELT,
  452.     AV_CODEC_ID_G723_1,
  453.     AV_CODEC_ID_G729,
  454.     AV_CODEC_ID_8SVX_EXP,
  455.     AV_CODEC_ID_8SVX_FIB,
  456.     AV_CODEC_ID_BMV_AUDIO,
  457.     AV_CODEC_ID_RALF,
  458.     AV_CODEC_ID_IAC,
  459.     AV_CODEC_ID_ILBC,
  460.     AV_CODEC_ID_OPUS_DEPRECATED,
  461.     AV_CODEC_ID_COMFORT_NOISE,
  462.     AV_CODEC_ID_TAK_DEPRECATED,
  463.     AV_CODEC_ID_METASOUND,
  464.     AV_CODEC_ID_FFWAVESYNTH = MKBETAG('F','F','W','S'),
  465.     AV_CODEC_ID_SONIC       = MKBETAG('S','O','N','C'),
  466.     AV_CODEC_ID_SONIC_LS    = MKBETAG('S','O','N','L'),
  467.     AV_CODEC_ID_PAF_AUDIO   = MKBETAG('P','A','F','A'),
  468.     AV_CODEC_ID_OPUS        = MKBETAG('O','P','U','S'),
  469.     AV_CODEC_ID_TAK         = MKBETAG('t','B','a','K'),
  470.     AV_CODEC_ID_EVRC        = MKBETAG('s','e','v','c'),
  471.     AV_CODEC_ID_SMV         = MKBETAG('s','s','m','v'),
  472.  
  473.     /* subtitle codecs */
  474.     AV_CODEC_ID_FIRST_SUBTITLE = 0x17000,          ///< A dummy ID pointing at the start of subtitle codecs.
  475.     AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
  476.     AV_CODEC_ID_DVB_SUBTITLE,
  477.     AV_CODEC_ID_TEXT,  ///< raw UTF-8 text
  478.     AV_CODEC_ID_XSUB,
  479.     AV_CODEC_ID_SSA,
  480.     AV_CODEC_ID_MOV_TEXT,
  481.     AV_CODEC_ID_HDMV_PGS_SUBTITLE,
  482.     AV_CODEC_ID_DVB_TELETEXT,
  483.     AV_CODEC_ID_SRT,
  484.     AV_CODEC_ID_MICRODVD   = MKBETAG('m','D','V','D'),
  485.     AV_CODEC_ID_EIA_608    = MKBETAG('c','6','0','8'),
  486.     AV_CODEC_ID_JACOSUB    = MKBETAG('J','S','U','B'),
  487.     AV_CODEC_ID_SAMI       = MKBETAG('S','A','M','I'),
  488.     AV_CODEC_ID_REALTEXT   = MKBETAG('R','T','X','T'),
  489.     AV_CODEC_ID_SUBVIEWER1 = MKBETAG('S','b','V','1'),
  490.     AV_CODEC_ID_SUBVIEWER  = MKBETAG('S','u','b','V'),
  491.     AV_CODEC_ID_SUBRIP     = MKBETAG('S','R','i','p'),
  492.     AV_CODEC_ID_WEBVTT     = MKBETAG('W','V','T','T'),
  493.     AV_CODEC_ID_MPL2       = MKBETAG('M','P','L','2'),
  494.     AV_CODEC_ID_VPLAYER    = MKBETAG('V','P','l','r'),
  495.     AV_CODEC_ID_PJS        = MKBETAG('P','h','J','S'),
  496.     AV_CODEC_ID_ASS        = MKBETAG('A','S','S',' '),  ///< ASS as defined in Matroska
  497.  
  498.     /* other specific kind of codecs (generally used for attachments) */
  499.     AV_CODEC_ID_FIRST_UNKNOWN = 0x18000,           ///< A dummy ID pointing at the start of various fake codecs.
  500.     AV_CODEC_ID_TTF = 0x18000,
  501.     AV_CODEC_ID_BINTEXT    = MKBETAG('B','T','X','T'),
  502.     AV_CODEC_ID_XBIN       = MKBETAG('X','B','I','N'),
  503.     AV_CODEC_ID_IDF        = MKBETAG( 0 ,'I','D','F'),
  504.     AV_CODEC_ID_OTF        = MKBETAG( 0 ,'O','T','F'),
  505.     AV_CODEC_ID_SMPTE_KLV  = MKBETAG('K','L','V','A'),
  506.     AV_CODEC_ID_DVD_NAV    = MKBETAG('D','N','A','V'),
  507.  
  508.  
  509.     AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
  510.  
  511.     AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
  512.                                 * stream (only used by libavformat) */
  513.     AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
  514.                                 * stream (only used by libavformat) */
  515.     AV_CODEC_ID_FFMETADATA = 0x21000,   ///< Dummy codec for streams containing only metadata information.
  516.  
  517. #if FF_API_CODEC_ID
  518. #include "old_codec_ids.h"
  519. #endif
  520. };
  521.  
  522. /**
  523.  * This struct describes the properties of a single codec described by an
  524.  * AVCodecID.
  525.  * @see avcodec_get_descriptor()
  526.  */
  527. typedef struct AVCodecDescriptor {
  528.     enum AVCodecID     id;
  529.     enum AVMediaType type;
  530.     /**
  531.      * Name of the codec described by this descriptor. It is non-empty and
  532.      * unique for each codec descriptor. It should contain alphanumeric
  533.      * characters and '_' only.
  534.      */
  535.     const char      *name;
  536.     /**
  537.      * A more descriptive name for this codec. May be NULL.
  538.      */
  539.     const char *long_name;
  540.     /**
  541.      * Codec properties, a combination of AV_CODEC_PROP_* flags.
  542.      */
  543.     int             props;
  544. } AVCodecDescriptor;
  545.  
  546. /**
  547.  * Codec uses only intra compression.
  548.  * Video codecs only.
  549.  */
  550. #define AV_CODEC_PROP_INTRA_ONLY    (1 << 0)
  551. /**
  552.  * Codec supports lossy compression. Audio and video codecs only.
  553.  * @note a codec may support both lossy and lossless
  554.  * compression modes
  555.  */
  556. #define AV_CODEC_PROP_LOSSY         (1 << 1)
  557. /**
  558.  * Codec supports lossless compression. Audio and video codecs only.
  559.  */
  560. #define AV_CODEC_PROP_LOSSLESS      (1 << 2)
  561. /**
  562.  * Subtitle codec is bitmap based
  563.  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
  564.  */
  565. #define AV_CODEC_PROP_BITMAP_SUB    (1 << 16)
  566. /**
  567.  * Subtitle codec is text based.
  568.  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
  569.  */
  570. #define AV_CODEC_PROP_TEXT_SUB      (1 << 17)
  571.  
  572. /**
  573.  * @ingroup lavc_decoding
  574.  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
  575.  * This is mainly needed because some optimized bitstream readers read
  576.  * 32 or 64 bit at once and could read over the end.<br>
  577.  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
  578.  * MPEG bitstreams could cause overread and segfault.
  579.  */
  580. #define FF_INPUT_BUFFER_PADDING_SIZE 16
  581.  
  582. /**
  583.  * @ingroup lavc_encoding
  584.  * minimum encoding buffer size
  585.  * Used to avoid some checks during header writing.
  586.  */
  587. #define FF_MIN_BUFFER_SIZE 16384
  588.  
  589.  
  590. /**
  591.  * @ingroup lavc_encoding
  592.  * motion estimation type.
  593.  */
  594. enum Motion_Est_ID {
  595.     ME_ZERO = 1,    ///< no search, that is use 0,0 vector whenever one is needed
  596.     ME_FULL,
  597.     ME_LOG,
  598.     ME_PHODS,
  599.     ME_EPZS,        ///< enhanced predictive zonal search
  600.     ME_X1,          ///< reserved for experiments
  601.     ME_HEX,         ///< hexagon based search
  602.     ME_UMH,         ///< uneven multi-hexagon search
  603.     ME_TESA,        ///< transformed exhaustive search algorithm
  604.     ME_ITER=50,     ///< iterative search
  605. };
  606.  
  607. /**
  608.  * @ingroup lavc_decoding
  609.  */
  610. enum AVDiscard{
  611.     /* We leave some space between them for extensions (drop some
  612.      * keyframes for intra-only or drop just some bidir frames). */
  613.     AVDISCARD_NONE    =-16, ///< discard nothing
  614.     AVDISCARD_DEFAULT =  0, ///< discard useless packets like 0 size packets in avi
  615.     AVDISCARD_NONREF  =  8, ///< discard all non reference
  616.     AVDISCARD_BIDIR   = 16, ///< discard all bidirectional frames
  617.     AVDISCARD_NONKEY  = 32, ///< discard all frames except keyframes
  618.     AVDISCARD_ALL     = 48, ///< discard all
  619. };
  620.  
  621. enum AVColorPrimaries{
  622.     AVCOL_PRI_BT709       = 1, ///< also ITU-R BT1361 / IEC 61966-2-4 / SMPTE RP177 Annex B
  623.     AVCOL_PRI_UNSPECIFIED = 2,
  624.     AVCOL_PRI_BT470M      = 4,
  625.     AVCOL_PRI_BT470BG     = 5, ///< also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM
  626.     AVCOL_PRI_SMPTE170M   = 6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC
  627.     AVCOL_PRI_SMPTE240M   = 7, ///< functionally identical to above
  628.     AVCOL_PRI_FILM        = 8,
  629.     AVCOL_PRI_NB             , ///< Not part of ABI
  630. };
  631.  
  632. enum AVColorTransferCharacteristic{
  633.     AVCOL_TRC_BT709       = 1, ///< also ITU-R BT1361
  634.     AVCOL_TRC_UNSPECIFIED = 2,
  635.     AVCOL_TRC_GAMMA22     = 4, ///< also ITU-R BT470M / ITU-R BT1700 625 PAL & SECAM
  636.     AVCOL_TRC_GAMMA28     = 5, ///< also ITU-R BT470BG
  637.     AVCOL_TRC_SMPTE240M   = 7,
  638.     AVCOL_TRC_NB             , ///< Not part of ABI
  639. };
  640.  
  641. /**
  642.  *  X   X      3 4 X      X are luma samples,
  643.  *             1 2        1-6 are possible chroma positions
  644.  *  X   X      5 6 X      0 is undefined/unknown position
  645.  */
  646. enum AVChromaLocation{
  647.     AVCHROMA_LOC_UNSPECIFIED = 0,
  648.     AVCHROMA_LOC_LEFT        = 1, ///< mpeg2/4, h264 default
  649.     AVCHROMA_LOC_CENTER      = 2, ///< mpeg1, jpeg, h263
  650.     AVCHROMA_LOC_TOPLEFT     = 3, ///< DV
  651.     AVCHROMA_LOC_TOP         = 4,
  652.     AVCHROMA_LOC_BOTTOMLEFT  = 5,
  653.     AVCHROMA_LOC_BOTTOM      = 6,
  654.     AVCHROMA_LOC_NB             , ///< Not part of ABI
  655. };
  656.  
  657. enum AVAudioServiceType {
  658.     AV_AUDIO_SERVICE_TYPE_MAIN              = 0,
  659.     AV_AUDIO_SERVICE_TYPE_EFFECTS           = 1,
  660.     AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
  661.     AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED  = 3,
  662.     AV_AUDIO_SERVICE_TYPE_DIALOGUE          = 4,
  663.     AV_AUDIO_SERVICE_TYPE_COMMENTARY        = 5,
  664.     AV_AUDIO_SERVICE_TYPE_EMERGENCY         = 6,
  665.     AV_AUDIO_SERVICE_TYPE_VOICE_OVER        = 7,
  666.     AV_AUDIO_SERVICE_TYPE_KARAOKE           = 8,
  667.     AV_AUDIO_SERVICE_TYPE_NB                   , ///< Not part of ABI
  668. };
  669.  
  670. /**
  671.  * @ingroup lavc_encoding
  672.  */
  673. typedef struct RcOverride{
  674.     int start_frame;
  675.     int end_frame;
  676.     int qscale; // If this is 0 then quality_factor will be used instead.
  677.     float quality_factor;
  678. } RcOverride;
  679.  
  680. #define FF_MAX_B_FRAMES 16
  681.  
  682. /* encoding support
  683.    These flags can be passed in AVCodecContext.flags before initialization.
  684.    Note: Not everything is supported yet.
  685. */
  686.  
  687. /**
  688.  * Allow decoders to produce frames with data planes that are not aligned
  689.  * to CPU requirements (e.g. due to cropping).
  690.  */
  691. #define CODEC_FLAG_UNALIGNED 0x0001
  692. #define CODEC_FLAG_QSCALE 0x0002  ///< Use fixed qscale.
  693. #define CODEC_FLAG_4MV    0x0004  ///< 4 MV per MB allowed / advanced prediction for H.263.
  694. #define CODEC_FLAG_QPEL   0x0010  ///< Use qpel MC.
  695. #define CODEC_FLAG_GMC    0x0020  ///< Use GMC.
  696. #define CODEC_FLAG_MV0    0x0040  ///< Always try a MB with MV=<0,0>.
  697. /**
  698.  * The parent program guarantees that the input for B-frames containing
  699.  * streams is not written to for at least s->max_b_frames+1 frames, if
  700.  * this is not set the input will be copied.
  701.  */
  702. #define CODEC_FLAG_INPUT_PRESERVED 0x0100
  703. #define CODEC_FLAG_PASS1           0x0200   ///< Use internal 2pass ratecontrol in first pass mode.
  704. #define CODEC_FLAG_PASS2           0x0400   ///< Use internal 2pass ratecontrol in second pass mode.
  705. #define CODEC_FLAG_GRAY            0x2000   ///< Only decode/encode grayscale.
  706. #define CODEC_FLAG_EMU_EDGE        0x4000   ///< Don't draw edges.
  707. #define CODEC_FLAG_PSNR            0x8000   ///< error[?] variables will be set during encoding.
  708. #define CODEC_FLAG_TRUNCATED       0x00010000 /** Input bitstream might be truncated at a random
  709.                                                   location instead of only at frame boundaries. */
  710. #define CODEC_FLAG_NORMALIZE_AQP  0x00020000 ///< Normalize adaptive quantization.
  711. #define CODEC_FLAG_INTERLACED_DCT 0x00040000 ///< Use interlaced DCT.
  712. #define CODEC_FLAG_LOW_DELAY      0x00080000 ///< Force low delay.
  713. #define CODEC_FLAG_GLOBAL_HEADER  0x00400000 ///< Place global headers in extradata instead of every keyframe.
  714. #define CODEC_FLAG_BITEXACT       0x00800000 ///< Use only bitexact stuff (except (I)DCT).
  715. /* Fx : Flag for h263+ extra options */
  716. #define CODEC_FLAG_AC_PRED        0x01000000 ///< H.263 advanced intra coding / MPEG-4 AC prediction
  717. #define CODEC_FLAG_LOOP_FILTER    0x00000800 ///< loop filter
  718. #define CODEC_FLAG_INTERLACED_ME  0x20000000 ///< interlaced motion estimation
  719. #define CODEC_FLAG_CLOSED_GOP     0x80000000
  720. #define CODEC_FLAG2_FAST          0x00000001 ///< Allow non spec compliant speedup tricks.
  721. #define CODEC_FLAG2_NO_OUTPUT     0x00000004 ///< Skip bitstream encoding.
  722. #define CODEC_FLAG2_LOCAL_HEADER  0x00000008 ///< Place global headers at every keyframe instead of in extradata.
  723. #define CODEC_FLAG2_DROP_FRAME_TIMECODE 0x00002000 ///< timecode is in drop frame format. DEPRECATED!!!!
  724. #define CODEC_FLAG2_IGNORE_CROP   0x00010000 ///< Discard cropping information from SPS.
  725.  
  726. #define CODEC_FLAG2_CHUNKS        0x00008000 ///< Input bitstream might be truncated at a packet boundaries instead of only at frame boundaries.
  727. #define CODEC_FLAG2_SHOW_ALL      0x00400000 ///< Show all frames before the first keyframe
  728.  
  729. /* Unsupported options :
  730.  *              Syntax Arithmetic coding (SAC)
  731.  *              Reference Picture Selection
  732.  *              Independent Segment Decoding */
  733. /* /Fx */
  734. /* codec capabilities */
  735.  
  736. #define CODEC_CAP_DRAW_HORIZ_BAND 0x0001 ///< Decoder can use draw_horiz_band callback.
  737. /**
  738.  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
  739.  * If not set, it might not use get_buffer() at all or use operations that
  740.  * assume the buffer was allocated by avcodec_default_get_buffer.
  741.  */
  742. #define CODEC_CAP_DR1             0x0002
  743. #define CODEC_CAP_TRUNCATED       0x0008
  744. /* Codec can export data for HW decoding (XvMC). */
  745. #define CODEC_CAP_HWACCEL         0x0010
  746. /**
  747.  * Encoder or decoder requires flushing with NULL input at the end in order to
  748.  * give the complete and correct output.
  749.  *
  750.  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
  751.  *       with NULL data. The user can still send NULL data to the public encode
  752.  *       or decode function, but libavcodec will not pass it along to the codec
  753.  *       unless this flag is set.
  754.  *
  755.  * Decoders:
  756.  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
  757.  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
  758.  * returns frames.
  759.  *
  760.  * Encoders:
  761.  * The encoder needs to be fed with NULL data at the end of encoding until the
  762.  * encoder no longer returns data.
  763.  *
  764.  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
  765.  *       flag also means that the encoder must set the pts and duration for
  766.  *       each output packet. If this flag is not set, the pts and duration will
  767.  *       be determined by libavcodec from the input frame.
  768.  */
  769. #define CODEC_CAP_DELAY           0x0020
  770. /**
  771.  * Codec can be fed a final frame with a smaller size.
  772.  * This can be used to prevent truncation of the last audio samples.
  773.  */
  774. #define CODEC_CAP_SMALL_LAST_FRAME 0x0040
  775. #if FF_API_CAP_VDPAU
  776. /**
  777.  * Codec can export data for HW decoding (VDPAU).
  778.  */
  779. #define CODEC_CAP_HWACCEL_VDPAU    0x0080
  780. #endif
  781. /**
  782.  * Codec can output multiple frames per AVPacket
  783.  * Normally demuxers return one frame at a time, demuxers which do not do
  784.  * are connected to a parser to split what they return into proper frames.
  785.  * This flag is reserved to the very rare category of codecs which have a
  786.  * bitstream that cannot be split into frames without timeconsuming
  787.  * operations like full decoding. Demuxers carring such bitstreams thus
  788.  * may return multiple frames in a packet. This has many disadvantages like
  789.  * prohibiting stream copy in many cases thus it should only be considered
  790.  * as a last resort.
  791.  */
  792. #define CODEC_CAP_SUBFRAMES        0x0100
  793. /**
  794.  * Codec is experimental and is thus avoided in favor of non experimental
  795.  * encoders
  796.  */
  797. #define CODEC_CAP_EXPERIMENTAL     0x0200
  798. /**
  799.  * Codec should fill in channel configuration and samplerate instead of container
  800.  */
  801. #define CODEC_CAP_CHANNEL_CONF     0x0400
  802.  
  803. /**
  804.  * Codec is able to deal with negative linesizes
  805.  */
  806. #define CODEC_CAP_NEG_LINESIZES    0x0800
  807.  
  808. /**
  809.  * Codec supports frame-level multithreading.
  810.  */
  811. #define CODEC_CAP_FRAME_THREADS    0x1000
  812. /**
  813.  * Codec supports slice-based (or partition-based) multithreading.
  814.  */
  815. #define CODEC_CAP_SLICE_THREADS    0x2000
  816. /**
  817.  * Codec supports changed parameters at any point.
  818.  */
  819. #define CODEC_CAP_PARAM_CHANGE     0x4000
  820. /**
  821.  * Codec supports avctx->thread_count == 0 (auto).
  822.  */
  823. #define CODEC_CAP_AUTO_THREADS     0x8000
  824. /**
  825.  * Audio encoder supports receiving a different number of samples in each call.
  826.  */
  827. #define CODEC_CAP_VARIABLE_FRAME_SIZE 0x10000
  828. /**
  829.  * Codec is intra only.
  830.  */
  831. #define CODEC_CAP_INTRA_ONLY       0x40000000
  832. /**
  833.  * Codec is lossless.
  834.  */
  835. #define CODEC_CAP_LOSSLESS         0x80000000
  836.  
  837. //The following defines may change, don't expect compatibility if you use them.
  838. #define MB_TYPE_INTRA4x4   0x0001
  839. #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
  840. #define MB_TYPE_INTRA_PCM  0x0004 //FIXME H.264-specific
  841. #define MB_TYPE_16x16      0x0008
  842. #define MB_TYPE_16x8       0x0010
  843. #define MB_TYPE_8x16       0x0020
  844. #define MB_TYPE_8x8        0x0040
  845. #define MB_TYPE_INTERLACED 0x0080
  846. #define MB_TYPE_DIRECT2    0x0100 //FIXME
  847. #define MB_TYPE_ACPRED     0x0200
  848. #define MB_TYPE_GMC        0x0400
  849. #define MB_TYPE_SKIP       0x0800
  850. #define MB_TYPE_P0L0       0x1000
  851. #define MB_TYPE_P1L0       0x2000
  852. #define MB_TYPE_P0L1       0x4000
  853. #define MB_TYPE_P1L1       0x8000
  854. #define MB_TYPE_L0         (MB_TYPE_P0L0 | MB_TYPE_P1L0)
  855. #define MB_TYPE_L1         (MB_TYPE_P0L1 | MB_TYPE_P1L1)
  856. #define MB_TYPE_L0L1       (MB_TYPE_L0   | MB_TYPE_L1)
  857. #define MB_TYPE_QUANT      0x00010000
  858. #define MB_TYPE_CBP        0x00020000
  859. //Note bits 24-31 are reserved for codec specific use (h264 ref0, mpeg1 0mv, ...)
  860.  
  861. /**
  862.  * Pan Scan area.
  863.  * This specifies the area which should be displayed.
  864.  * Note there may be multiple such areas for one frame.
  865.  */
  866. typedef struct AVPanScan{
  867.     /**
  868.      * id
  869.      * - encoding: Set by user.
  870.      * - decoding: Set by libavcodec.
  871.      */
  872.     int id;
  873.  
  874.     /**
  875.      * width and height in 1/16 pel
  876.      * - encoding: Set by user.
  877.      * - decoding: Set by libavcodec.
  878.      */
  879.     int width;
  880.     int height;
  881.  
  882.     /**
  883.      * position of the top left corner in 1/16 pel for up to 3 fields/frames
  884.      * - encoding: Set by user.
  885.      * - decoding: Set by libavcodec.
  886.      */
  887.     int16_t position[3][2];
  888. }AVPanScan;
  889.  
  890. #define FF_QSCALE_TYPE_MPEG1 0
  891. #define FF_QSCALE_TYPE_MPEG2 1
  892. #define FF_QSCALE_TYPE_H264  2
  893. #define FF_QSCALE_TYPE_VP56  3
  894.  
  895. #if FF_API_GET_BUFFER
  896. #define FF_BUFFER_TYPE_INTERNAL 1
  897. #define FF_BUFFER_TYPE_USER     2 ///< direct rendering buffers (image is (de)allocated by user)
  898. #define FF_BUFFER_TYPE_SHARED   4 ///< Buffer from somewhere else; don't deallocate image (data/base), all other tables are not shared.
  899. #define FF_BUFFER_TYPE_COPY     8 ///< Just a (modified) copy of some other buffer, don't deallocate anything.
  900.  
  901. #define FF_BUFFER_HINTS_VALID    0x01 // Buffer hints value is meaningful (if 0 ignore).
  902. #define FF_BUFFER_HINTS_READABLE 0x02 // Codec will read from buffer.
  903. #define FF_BUFFER_HINTS_PRESERVE 0x04 // User must not alter buffer content.
  904. #define FF_BUFFER_HINTS_REUSABLE 0x08 // Codec will reuse the buffer (update).
  905. #endif
  906.  
  907. /**
  908.  * The decoder will keep a reference to the frame and may reuse it later.
  909.  */
  910. #define AV_GET_BUFFER_FLAG_REF (1 << 0)
  911.  
  912. /**
  913.  * @defgroup lavc_packet AVPacket
  914.  *
  915.  * Types and functions for working with AVPacket.
  916.  * @{
  917.  */
  918. enum AVPacketSideDataType {
  919.     AV_PKT_DATA_PALETTE,
  920.     AV_PKT_DATA_NEW_EXTRADATA,
  921.  
  922.     /**
  923.      * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
  924.      * @code
  925.      * u32le param_flags
  926.      * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
  927.      *     s32le channel_count
  928.      * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
  929.      *     u64le channel_layout
  930.      * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
  931.      *     s32le sample_rate
  932.      * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
  933.      *     s32le width
  934.      *     s32le height
  935.      * @endcode
  936.      */
  937.     AV_PKT_DATA_PARAM_CHANGE,
  938.  
  939.     /**
  940.      * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
  941.      * structures with info about macroblocks relevant to splitting the
  942.      * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
  943.      * That is, it does not necessarily contain info about all macroblocks,
  944.      * as long as the distance between macroblocks in the info is smaller
  945.      * than the target payload size.
  946.      * Each MB info structure is 12 bytes, and is laid out as follows:
  947.      * @code
  948.      * u32le bit offset from the start of the packet
  949.      * u8    current quantizer at the start of the macroblock
  950.      * u8    GOB number
  951.      * u16le macroblock address within the GOB
  952.      * u8    horizontal MV predictor
  953.      * u8    vertical MV predictor
  954.      * u8    horizontal MV predictor for block number 3
  955.      * u8    vertical MV predictor for block number 3
  956.      * @endcode
  957.      */
  958.     AV_PKT_DATA_H263_MB_INFO,
  959.  
  960.     /**
  961.      * Recommmends skipping the specified number of samples
  962.      * @code
  963.      * u32le number of samples to skip from start of this packet
  964.      * u32le number of samples to skip from end of this packet
  965.      * u8    reason for start skip
  966.      * u8    reason for end   skip (0=padding silence, 1=convergence)
  967.      * @endcode
  968.      */
  969.     AV_PKT_DATA_SKIP_SAMPLES=70,
  970.  
  971.     /**
  972.      * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
  973.      * the packet may contain "dual mono" audio specific to Japanese DTV
  974.      * and if it is true, recommends only the selected channel to be used.
  975.      * @code
  976.      * u8    selected channels (0=mail/left, 1=sub/right, 2=both)
  977.      * @endcode
  978.      */
  979.     AV_PKT_DATA_JP_DUALMONO,
  980.  
  981.     /**
  982.      * A list of zero terminated key/value strings. There is no end marker for
  983.      * the list, so it is required to rely on the side data size to stop.
  984.      */
  985.     AV_PKT_DATA_STRINGS_METADATA,
  986.  
  987.     /**
  988.      * Subtitle event position
  989.      * @code
  990.      * u32le x1
  991.      * u32le y1
  992.      * u32le x2
  993.      * u32le y2
  994.      * @endcode
  995.      */
  996.     AV_PKT_DATA_SUBTITLE_POSITION,
  997.  
  998.     /**
  999.      * Data found in BlockAdditional element of matroska container. There is
  1000.      * no end marker for the data, so it is required to rely on the side data
  1001.      * size to recognize the end. 8 byte id (as found in BlockAddId) followed
  1002.      * by data.
  1003.      */
  1004.     AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
  1005.  
  1006.     /**
  1007.      * The optional first identifier line of a WebVTT cue.
  1008.      */
  1009.     AV_PKT_DATA_WEBVTT_IDENTIFIER,
  1010.  
  1011.     /**
  1012.      * The optional settings (rendering instructions) that immediately
  1013.      * follow the timestamp specifier of a WebVTT cue.
  1014.      */
  1015.     AV_PKT_DATA_WEBVTT_SETTINGS,
  1016. };
  1017.  
  1018. /**
  1019.  * This structure stores compressed data. It is typically exported by demuxers
  1020.  * and then passed as input to decoders, or received as output from encoders and
  1021.  * then passed to muxers.
  1022.  *
  1023.  * For video, it should typically contain one compressed frame. For audio it may
  1024.  * contain several compressed frames.
  1025.  *
  1026.  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
  1027.  * ABI. Thus it may be allocated on stack and no new fields can be added to it
  1028.  * without libavcodec and libavformat major bump.
  1029.  *
  1030.  * The semantics of data ownership depends on the buf or destruct (deprecated)
  1031.  * fields. If either is set, the packet data is dynamically allocated and is
  1032.  * valid indefinitely until av_free_packet() is called (which in turn calls
  1033.  * av_buffer_unref()/the destruct callback to free the data). If neither is set,
  1034.  * the packet data is typically backed by some static buffer somewhere and is
  1035.  * only valid for a limited time (e.g. until the next read call when demuxing).
  1036.  *
  1037.  * The side data is always allocated with av_malloc() and is freed in
  1038.  * av_free_packet().
  1039.  */
  1040. typedef struct AVPacket {
  1041.     /**
  1042.      * A reference to the reference-counted buffer where the packet data is
  1043.      * stored.
  1044.      * May be NULL, then the packet data is not reference-counted.
  1045.      */
  1046.     AVBufferRef *buf;
  1047.     /**
  1048.      * Presentation timestamp in AVStream->time_base units; the time at which
  1049.      * the decompressed packet will be presented to the user.
  1050.      * Can be AV_NOPTS_VALUE if it is not stored in the file.
  1051.      * pts MUST be larger or equal to dts as presentation cannot happen before
  1052.      * decompression, unless one wants to view hex dumps. Some formats misuse
  1053.      * the terms dts and pts/cts to mean something different. Such timestamps
  1054.      * must be converted to true pts/dts before they are stored in AVPacket.
  1055.      */
  1056.     int64_t pts;
  1057.     /**
  1058.      * Decompression timestamp in AVStream->time_base units; the time at which
  1059.      * the packet is decompressed.
  1060.      * Can be AV_NOPTS_VALUE if it is not stored in the file.
  1061.      */
  1062.     int64_t dts;
  1063.     uint8_t *data;
  1064.     int   size;
  1065.     int   stream_index;
  1066.     /**
  1067.      * A combination of AV_PKT_FLAG values
  1068.      */
  1069.     int   flags;
  1070.     /**
  1071.      * Additional packet data that can be provided by the container.
  1072.      * Packet can contain several types of side information.
  1073.      */
  1074.     struct {
  1075.         uint8_t *data;
  1076.         int      size;
  1077.         enum AVPacketSideDataType type;
  1078.     } *side_data;
  1079.     int side_data_elems;
  1080.  
  1081.     /**
  1082.      * Duration of this packet in AVStream->time_base units, 0 if unknown.
  1083.      * Equals next_pts - this_pts in presentation order.
  1084.      */
  1085.     int   duration;
  1086. #if FF_API_DESTRUCT_PACKET
  1087.     attribute_deprecated
  1088.     void  (*destruct)(struct AVPacket *);
  1089.     attribute_deprecated
  1090.     void  *priv;
  1091. #endif
  1092.     int64_t pos;                            ///< byte position in stream, -1 if unknown
  1093.  
  1094.     /**
  1095.      * Time difference in AVStream->time_base units from the pts of this
  1096.      * packet to the point at which the output from the decoder has converged
  1097.      * independent from the availability of previous frames. That is, the
  1098.      * frames are virtually identical no matter if decoding started from
  1099.      * the very first frame or from this keyframe.
  1100.      * Is AV_NOPTS_VALUE if unknown.
  1101.      * This field is not the display duration of the current packet.
  1102.      * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
  1103.      * set.
  1104.      *
  1105.      * The purpose of this field is to allow seeking in streams that have no
  1106.      * keyframes in the conventional sense. It corresponds to the
  1107.      * recovery point SEI in H.264 and match_time_delta in NUT. It is also
  1108.      * essential for some types of subtitle streams to ensure that all
  1109.      * subtitles are correctly displayed after seeking.
  1110.      */
  1111.     int64_t convergence_duration;
  1112. } AVPacket;
  1113. #define AV_PKT_FLAG_KEY     0x0001 ///< The packet contains a keyframe
  1114. #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
  1115.  
  1116. enum AVSideDataParamChangeFlags {
  1117.     AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT  = 0x0001,
  1118.     AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
  1119.     AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE    = 0x0004,
  1120.     AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS     = 0x0008,
  1121. };
  1122. /**
  1123.  * @}
  1124.  */
  1125.  
  1126. struct AVCodecInternal;
  1127.  
  1128. enum AVFieldOrder {
  1129.     AV_FIELD_UNKNOWN,
  1130.     AV_FIELD_PROGRESSIVE,
  1131.     AV_FIELD_TT,          //< Top coded_first, top displayed first
  1132.     AV_FIELD_BB,          //< Bottom coded first, bottom displayed first
  1133.     AV_FIELD_TB,          //< Top coded first, bottom displayed first
  1134.     AV_FIELD_BT,          //< Bottom coded first, top displayed first
  1135. };
  1136.  
  1137. /**
  1138.  * main external API structure.
  1139.  * New fields can be added to the end with minor version bumps.
  1140.  * Removal, reordering and changes to existing fields require a major
  1141.  * version bump.
  1142.  * Please use AVOptions (av_opt* / av_set/get*()) to access these fields from user
  1143.  * applications.
  1144.  * sizeof(AVCodecContext) must not be used outside libav*.
  1145.  */
  1146. typedef struct AVCodecContext {
  1147.     /**
  1148.      * information on struct for av_log
  1149.      * - set by avcodec_alloc_context3
  1150.      */
  1151.     const AVClass *av_class;
  1152.     int log_level_offset;
  1153.  
  1154.     enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
  1155.     const struct AVCodec  *codec;
  1156.     char             codec_name[32];
  1157.     enum AVCodecID     codec_id; /* see AV_CODEC_ID_xxx */
  1158.  
  1159.     /**
  1160.      * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
  1161.      * This is used to work around some encoder bugs.
  1162.      * A demuxer should set this to what is stored in the field used to identify the codec.
  1163.      * If there are multiple such fields in a container then the demuxer should choose the one
  1164.      * which maximizes the information about the used codec.
  1165.      * If the codec tag field in a container is larger than 32 bits then the demuxer should
  1166.      * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
  1167.      * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
  1168.      * first.
  1169.      * - encoding: Set by user, if not then the default based on codec_id will be used.
  1170.      * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
  1171.      */
  1172.     unsigned int codec_tag;
  1173.  
  1174.     /**
  1175.      * fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
  1176.      * This is used to work around some encoder bugs.
  1177.      * - encoding: unused
  1178.      * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
  1179.      */
  1180.     unsigned int stream_codec_tag;
  1181.  
  1182.     void *priv_data;
  1183.  
  1184.     /**
  1185.      * Private context used for internal data.
  1186.      *
  1187.      * Unlike priv_data, this is not codec-specific. It is used in general
  1188.      * libavcodec functions.
  1189.      */
  1190.     struct AVCodecInternal *internal;
  1191.  
  1192.     /**
  1193.      * Private data of the user, can be used to carry app specific stuff.
  1194.      * - encoding: Set by user.
  1195.      * - decoding: Set by user.
  1196.      */
  1197.     void *opaque;
  1198.  
  1199.     /**
  1200.      * the average bitrate
  1201.      * - encoding: Set by user; unused for constant quantizer encoding.
  1202.      * - decoding: Set by libavcodec. 0 or some bitrate if this info is available in the stream.
  1203.      */
  1204.     int bit_rate;
  1205.  
  1206.     /**
  1207.      * number of bits the bitstream is allowed to diverge from the reference.
  1208.      *           the reference can be CBR (for CBR pass1) or VBR (for pass2)
  1209.      * - encoding: Set by user; unused for constant quantizer encoding.
  1210.      * - decoding: unused
  1211.      */
  1212.     int bit_rate_tolerance;
  1213.  
  1214.     /**
  1215.      * Global quality for codecs which cannot change it per frame.
  1216.      * This should be proportional to MPEG-1/2/4 qscale.
  1217.      * - encoding: Set by user.
  1218.      * - decoding: unused
  1219.      */
  1220.     int global_quality;
  1221.  
  1222.     /**
  1223.      * - encoding: Set by user.
  1224.      * - decoding: unused
  1225.      */
  1226.     int compression_level;
  1227. #define FF_COMPRESSION_DEFAULT -1
  1228.  
  1229.     /**
  1230.      * CODEC_FLAG_*.
  1231.      * - encoding: Set by user.
  1232.      * - decoding: Set by user.
  1233.      */
  1234.     int flags;
  1235.  
  1236.     /**
  1237.      * CODEC_FLAG2_*
  1238.      * - encoding: Set by user.
  1239.      * - decoding: Set by user.
  1240.      */
  1241.     int flags2;
  1242.  
  1243.     /**
  1244.      * some codecs need / can use extradata like Huffman tables.
  1245.      * mjpeg: Huffman tables
  1246.      * rv10: additional flags
  1247.      * mpeg4: global headers (they can be in the bitstream or here)
  1248.      * The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
  1249.      * than extradata_size to avoid problems if it is read with the bitstream reader.
  1250.      * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
  1251.      * - encoding: Set/allocated/freed by libavcodec.
  1252.      * - decoding: Set/allocated/freed by user.
  1253.      */
  1254.     uint8_t *extradata;
  1255.     int extradata_size;
  1256.  
  1257.     /**
  1258.      * This is the fundamental unit of time (in seconds) in terms
  1259.      * of which frame timestamps are represented. For fixed-fps content,
  1260.      * timebase should be 1/framerate and timestamp increments should be
  1261.      * identically 1.
  1262.      * - encoding: MUST be set by user.
  1263.      * - decoding: Set by libavcodec.
  1264.      */
  1265.     AVRational time_base;
  1266.  
  1267.     /**
  1268.      * For some codecs, the time base is closer to the field rate than the frame rate.
  1269.      * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
  1270.      * if no telecine is used ...
  1271.      *
  1272.      * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
  1273.      */
  1274.     int ticks_per_frame;
  1275.  
  1276.     /**
  1277.      * Codec delay.
  1278.      *
  1279.      * Encoding: Number of frames delay there will be from the encoder input to
  1280.      *           the decoder output. (we assume the decoder matches the spec)
  1281.      * Decoding: Number of frames delay in addition to what a standard decoder
  1282.      *           as specified in the spec would produce.
  1283.      *
  1284.      * Video:
  1285.      *   Number of frames the decoded output will be delayed relative to the
  1286.      *   encoded input.
  1287.      *
  1288.      * Audio:
  1289.      *   For encoding, this is the number of "priming" samples added to the
  1290.      *   beginning of the stream. The decoded output will be delayed by this
  1291.      *   many samples relative to the input to the encoder. Note that this
  1292.      *   field is purely informational and does not directly affect the pts
  1293.      *   output by the encoder, which should always be based on the actual
  1294.      *   presentation time, including any delay.
  1295.      *   For decoding, this is the number of samples the decoder needs to
  1296.      *   output before the decoder's output is valid. When seeking, you should
  1297.      *   start decoding this many samples prior to your desired seek point.
  1298.      *
  1299.      * - encoding: Set by libavcodec.
  1300.      * - decoding: Set by libavcodec.
  1301.      */
  1302.     int delay;
  1303.  
  1304.  
  1305.     /* video only */
  1306.     /**
  1307.      * picture width / height.
  1308.      * - encoding: MUST be set by user.
  1309.      * - decoding: May be set by the user before opening the decoder if known e.g.
  1310.      *             from the container. Some decoders will require the dimensions
  1311.      *             to be set by the caller. During decoding, the decoder may
  1312.      *             overwrite those values as required.
  1313.      */
  1314.     int width, height;
  1315.  
  1316.     /**
  1317.      * Bitstream width / height, may be different from width/height e.g. when
  1318.      * the decoded frame is cropped before being output or lowres is enabled.
  1319.      * - encoding: unused
  1320.      * - decoding: May be set by the user before opening the decoder if known
  1321.      *             e.g. from the container. During decoding, the decoder may
  1322.      *             overwrite those values as required.
  1323.      */
  1324.     int coded_width, coded_height;
  1325.  
  1326. #define FF_ASPECT_EXTENDED 15
  1327.  
  1328.     /**
  1329.      * the number of pictures in a group of pictures, or 0 for intra_only
  1330.      * - encoding: Set by user.
  1331.      * - decoding: unused
  1332.      */
  1333.     int gop_size;
  1334.  
  1335.     /**
  1336.      * Pixel format, see AV_PIX_FMT_xxx.
  1337.      * May be set by the demuxer if known from headers.
  1338.      * May be overridden by the decoder if it knows better.
  1339.      * - encoding: Set by user.
  1340.      * - decoding: Set by user if known, overridden by libavcodec if known
  1341.      */
  1342.     enum AVPixelFormat pix_fmt;
  1343.  
  1344.     /**
  1345.      * Motion estimation algorithm used for video coding.
  1346.      * 1 (zero), 2 (full), 3 (log), 4 (phods), 5 (epzs), 6 (x1), 7 (hex),
  1347.      * 8 (umh), 9 (iter), 10 (tesa) [7, 8, 10 are x264 specific, 9 is snow specific]
  1348.      * - encoding: MUST be set by user.
  1349.      * - decoding: unused
  1350.      */
  1351.     int me_method;
  1352.  
  1353.     /**
  1354.      * If non NULL, 'draw_horiz_band' is called by the libavcodec
  1355.      * decoder to draw a horizontal band. It improves cache usage. Not
  1356.      * all codecs can do that. You must check the codec capabilities
  1357.      * beforehand.
  1358.      * When multithreading is used, it may be called from multiple threads
  1359.      * at the same time; threads might draw different parts of the same AVFrame,
  1360.      * or multiple AVFrames, and there is no guarantee that slices will be drawn
  1361.      * in order.
  1362.      * The function is also used by hardware acceleration APIs.
  1363.      * It is called at least once during frame decoding to pass
  1364.      * the data needed for hardware render.
  1365.      * In that mode instead of pixel data, AVFrame points to
  1366.      * a structure specific to the acceleration API. The application
  1367.      * reads the structure and can change some fields to indicate progress
  1368.      * or mark state.
  1369.      * - encoding: unused
  1370.      * - decoding: Set by user.
  1371.      * @param height the height of the slice
  1372.      * @param y the y position of the slice
  1373.      * @param type 1->top field, 2->bottom field, 3->frame
  1374.      * @param offset offset into the AVFrame.data from which the slice should be read
  1375.      */
  1376.     void (*draw_horiz_band)(struct AVCodecContext *s,
  1377.                             const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
  1378.                             int y, int type, int height);
  1379.  
  1380.     /**
  1381.      * callback to negotiate the pixelFormat
  1382.      * @param fmt is the list of formats which are supported by the codec,
  1383.      * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
  1384.      * The first is always the native one.
  1385.      * @return the chosen format
  1386.      * - encoding: unused
  1387.      * - decoding: Set by user, if not set the native format will be chosen.
  1388.      */
  1389.     enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
  1390.  
  1391.     /**
  1392.      * maximum number of B-frames between non-B-frames
  1393.      * Note: The output will be delayed by max_b_frames+1 relative to the input.
  1394.      * - encoding: Set by user.
  1395.      * - decoding: unused
  1396.      */
  1397.     int max_b_frames;
  1398.  
  1399.     /**
  1400.      * qscale factor between IP and B-frames
  1401.      * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
  1402.      * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
  1403.      * - encoding: Set by user.
  1404.      * - decoding: unused
  1405.      */
  1406.     float b_quant_factor;
  1407.  
  1408.     /** obsolete FIXME remove */
  1409.     int rc_strategy;
  1410. #define FF_RC_STRATEGY_XVID 1
  1411.  
  1412.     int b_frame_strategy;
  1413.  
  1414.     /**
  1415.      * qscale offset between IP and B-frames
  1416.      * - encoding: Set by user.
  1417.      * - decoding: unused
  1418.      */
  1419.     float b_quant_offset;
  1420.  
  1421.     /**
  1422.      * Size of the frame reordering buffer in the decoder.
  1423.      * For MPEG-2 it is 1 IPB or 0 low delay IP.
  1424.      * - encoding: Set by libavcodec.
  1425.      * - decoding: Set by libavcodec.
  1426.      */
  1427.     int has_b_frames;
  1428.  
  1429.     /**
  1430.      * 0-> h263 quant 1-> mpeg quant
  1431.      * - encoding: Set by user.
  1432.      * - decoding: unused
  1433.      */
  1434.     int mpeg_quant;
  1435.  
  1436.     /**
  1437.      * qscale factor between P and I-frames
  1438.      * If > 0 then the last p frame quantizer will be used (q= lastp_q*factor+offset).
  1439.      * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
  1440.      * - encoding: Set by user.
  1441.      * - decoding: unused
  1442.      */
  1443.     float i_quant_factor;
  1444.  
  1445.     /**
  1446.      * qscale offset between P and I-frames
  1447.      * - encoding: Set by user.
  1448.      * - decoding: unused
  1449.      */
  1450.     float i_quant_offset;
  1451.  
  1452.     /**
  1453.      * luminance masking (0-> disabled)
  1454.      * - encoding: Set by user.
  1455.      * - decoding: unused
  1456.      */
  1457.     float lumi_masking;
  1458.  
  1459.     /**
  1460.      * temporary complexity masking (0-> disabled)
  1461.      * - encoding: Set by user.
  1462.      * - decoding: unused
  1463.      */
  1464.     float temporal_cplx_masking;
  1465.  
  1466.     /**
  1467.      * spatial complexity masking (0-> disabled)
  1468.      * - encoding: Set by user.
  1469.      * - decoding: unused
  1470.      */
  1471.     float spatial_cplx_masking;
  1472.  
  1473.     /**
  1474.      * p block masking (0-> disabled)
  1475.      * - encoding: Set by user.
  1476.      * - decoding: unused
  1477.      */
  1478.     float p_masking;
  1479.  
  1480.     /**
  1481.      * darkness masking (0-> disabled)
  1482.      * - encoding: Set by user.
  1483.      * - decoding: unused
  1484.      */
  1485.     float dark_masking;
  1486.  
  1487.     /**
  1488.      * slice count
  1489.      * - encoding: Set by libavcodec.
  1490.      * - decoding: Set by user (or 0).
  1491.      */
  1492.     int slice_count;
  1493.     /**
  1494.      * prediction method (needed for huffyuv)
  1495.      * - encoding: Set by user.
  1496.      * - decoding: unused
  1497.      */
  1498.      int prediction_method;
  1499. #define FF_PRED_LEFT   0
  1500. #define FF_PRED_PLANE  1
  1501. #define FF_PRED_MEDIAN 2
  1502.  
  1503.     /**
  1504.      * slice offsets in the frame in bytes
  1505.      * - encoding: Set/allocated by libavcodec.
  1506.      * - decoding: Set/allocated by user (or NULL).
  1507.      */
  1508.     int *slice_offset;
  1509.  
  1510.     /**
  1511.      * sample aspect ratio (0 if unknown)
  1512.      * That is the width of a pixel divided by the height of the pixel.
  1513.      * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
  1514.      * - encoding: Set by user.
  1515.      * - decoding: Set by libavcodec.
  1516.      */
  1517.     AVRational sample_aspect_ratio;
  1518.  
  1519.     /**
  1520.      * motion estimation comparison function
  1521.      * - encoding: Set by user.
  1522.      * - decoding: unused
  1523.      */
  1524.     int me_cmp;
  1525.     /**
  1526.      * subpixel motion estimation comparison function
  1527.      * - encoding: Set by user.
  1528.      * - decoding: unused
  1529.      */
  1530.     int me_sub_cmp;
  1531.     /**
  1532.      * macroblock comparison function (not supported yet)
  1533.      * - encoding: Set by user.
  1534.      * - decoding: unused
  1535.      */
  1536.     int mb_cmp;
  1537.     /**
  1538.      * interlaced DCT comparison function
  1539.      * - encoding: Set by user.
  1540.      * - decoding: unused
  1541.      */
  1542.     int ildct_cmp;
  1543. #define FF_CMP_SAD    0
  1544. #define FF_CMP_SSE    1
  1545. #define FF_CMP_SATD   2
  1546. #define FF_CMP_DCT    3
  1547. #define FF_CMP_PSNR   4
  1548. #define FF_CMP_BIT    5
  1549. #define FF_CMP_RD     6
  1550. #define FF_CMP_ZERO   7
  1551. #define FF_CMP_VSAD   8
  1552. #define FF_CMP_VSSE   9
  1553. #define FF_CMP_NSSE   10
  1554. #define FF_CMP_W53    11
  1555. #define FF_CMP_W97    12
  1556. #define FF_CMP_DCTMAX 13
  1557. #define FF_CMP_DCT264 14
  1558. #define FF_CMP_CHROMA 256
  1559.  
  1560.     /**
  1561.      * ME diamond size & shape
  1562.      * - encoding: Set by user.
  1563.      * - decoding: unused
  1564.      */
  1565.     int dia_size;
  1566.  
  1567.     /**
  1568.      * amount of previous MV predictors (2a+1 x 2a+1 square)
  1569.      * - encoding: Set by user.
  1570.      * - decoding: unused
  1571.      */
  1572.     int last_predictor_count;
  1573.  
  1574.     /**
  1575.      * prepass for motion estimation
  1576.      * - encoding: Set by user.
  1577.      * - decoding: unused
  1578.      */
  1579.     int pre_me;
  1580.  
  1581.     /**
  1582.      * motion estimation prepass comparison function
  1583.      * - encoding: Set by user.
  1584.      * - decoding: unused
  1585.      */
  1586.     int me_pre_cmp;
  1587.  
  1588.     /**
  1589.      * ME prepass diamond size & shape
  1590.      * - encoding: Set by user.
  1591.      * - decoding: unused
  1592.      */
  1593.     int pre_dia_size;
  1594.  
  1595.     /**
  1596.      * subpel ME quality
  1597.      * - encoding: Set by user.
  1598.      * - decoding: unused
  1599.      */
  1600.     int me_subpel_quality;
  1601.  
  1602.     /**
  1603.      * DTG active format information (additional aspect ratio
  1604.      * information only used in DVB MPEG-2 transport streams)
  1605.      * 0 if not set.
  1606.      *
  1607.      * - encoding: unused
  1608.      * - decoding: Set by decoder.
  1609.      */
  1610.     int dtg_active_format;
  1611. #define FF_DTG_AFD_SAME         8
  1612. #define FF_DTG_AFD_4_3          9
  1613. #define FF_DTG_AFD_16_9         10
  1614. #define FF_DTG_AFD_14_9         11
  1615. #define FF_DTG_AFD_4_3_SP_14_9  13
  1616. #define FF_DTG_AFD_16_9_SP_14_9 14
  1617. #define FF_DTG_AFD_SP_4_3       15
  1618.  
  1619.     /**
  1620.      * maximum motion estimation search range in subpel units
  1621.      * If 0 then no limit.
  1622.      *
  1623.      * - encoding: Set by user.
  1624.      * - decoding: unused
  1625.      */
  1626.     int me_range;
  1627.  
  1628.     /**
  1629.      * intra quantizer bias
  1630.      * - encoding: Set by user.
  1631.      * - decoding: unused
  1632.      */
  1633.     int intra_quant_bias;
  1634. #define FF_DEFAULT_QUANT_BIAS 999999
  1635.  
  1636.     /**
  1637.      * inter quantizer bias
  1638.      * - encoding: Set by user.
  1639.      * - decoding: unused
  1640.      */
  1641.     int inter_quant_bias;
  1642.  
  1643.     /**
  1644.      * slice flags
  1645.      * - encoding: unused
  1646.      * - decoding: Set by user.
  1647.      */
  1648.     int slice_flags;
  1649. #define SLICE_FLAG_CODED_ORDER    0x0001 ///< draw_horiz_band() is called in coded order instead of display
  1650. #define SLICE_FLAG_ALLOW_FIELD    0x0002 ///< allow draw_horiz_band() with field slices (MPEG2 field pics)
  1651. #define SLICE_FLAG_ALLOW_PLANE    0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
  1652.  
  1653.     /**
  1654.      * XVideo Motion Acceleration
  1655.      * - encoding: forbidden
  1656.      * - decoding: set by decoder
  1657.      */
  1658.     int xvmc_acceleration;
  1659.  
  1660.     /**
  1661.      * macroblock decision mode
  1662.      * - encoding: Set by user.
  1663.      * - decoding: unused
  1664.      */
  1665.     int mb_decision;
  1666. #define FF_MB_DECISION_SIMPLE 0        ///< uses mb_cmp
  1667. #define FF_MB_DECISION_BITS   1        ///< chooses the one which needs the fewest bits
  1668. #define FF_MB_DECISION_RD     2        ///< rate distortion
  1669.  
  1670.     /**
  1671.      * custom intra quantization matrix
  1672.      * - encoding: Set by user, can be NULL.
  1673.      * - decoding: Set by libavcodec.
  1674.      */
  1675.     uint16_t *intra_matrix;
  1676.  
  1677.     /**
  1678.      * custom inter quantization matrix
  1679.      * - encoding: Set by user, can be NULL.
  1680.      * - decoding: Set by libavcodec.
  1681.      */
  1682.     uint16_t *inter_matrix;
  1683.  
  1684.     /**
  1685.      * scene change detection threshold
  1686.      * 0 is default, larger means fewer detected scene changes.
  1687.      * - encoding: Set by user.
  1688.      * - decoding: unused
  1689.      */
  1690.     int scenechange_threshold;
  1691.  
  1692.     /**
  1693.      * noise reduction strength
  1694.      * - encoding: Set by user.
  1695.      * - decoding: unused
  1696.      */
  1697.     int noise_reduction;
  1698.  
  1699.     /**
  1700.      * Motion estimation threshold below which no motion estimation is
  1701.      * performed, but instead the user specified motion vectors are used.
  1702.      *
  1703.      * - encoding: Set by user.
  1704.      * - decoding: unused
  1705.      */
  1706.     int me_threshold;
  1707.  
  1708.     /**
  1709.      * Macroblock threshold below which the user specified macroblock types will be used.
  1710.      * - encoding: Set by user.
  1711.      * - decoding: unused
  1712.      */
  1713.     int mb_threshold;
  1714.  
  1715.     /**
  1716.      * precision of the intra DC coefficient - 8
  1717.      * - encoding: Set by user.
  1718.      * - decoding: unused
  1719.      */
  1720.     int intra_dc_precision;
  1721.  
  1722.     /**
  1723.      * Number of macroblock rows at the top which are skipped.
  1724.      * - encoding: unused
  1725.      * - decoding: Set by user.
  1726.      */
  1727.     int skip_top;
  1728.  
  1729.     /**
  1730.      * Number of macroblock rows at the bottom which are skipped.
  1731.      * - encoding: unused
  1732.      * - decoding: Set by user.
  1733.      */
  1734.     int skip_bottom;
  1735.  
  1736.     /**
  1737.      * Border processing masking, raises the quantizer for mbs on the borders
  1738.      * of the picture.
  1739.      * - encoding: Set by user.
  1740.      * - decoding: unused
  1741.      */
  1742.     float border_masking;
  1743.  
  1744.     /**
  1745.      * minimum MB lagrange multipler
  1746.      * - encoding: Set by user.
  1747.      * - decoding: unused
  1748.      */
  1749.     int mb_lmin;
  1750.  
  1751.     /**
  1752.      * maximum MB lagrange multipler
  1753.      * - encoding: Set by user.
  1754.      * - decoding: unused
  1755.      */
  1756.     int mb_lmax;
  1757.  
  1758.     /**
  1759.      *
  1760.      * - encoding: Set by user.
  1761.      * - decoding: unused
  1762.      */
  1763.     int me_penalty_compensation;
  1764.  
  1765.     /**
  1766.      *
  1767.      * - encoding: Set by user.
  1768.      * - decoding: unused
  1769.      */
  1770.     int bidir_refine;
  1771.  
  1772.     /**
  1773.      *
  1774.      * - encoding: Set by user.
  1775.      * - decoding: unused
  1776.      */
  1777.     int brd_scale;
  1778.  
  1779.     /**
  1780.      * minimum GOP size
  1781.      * - encoding: Set by user.
  1782.      * - decoding: unused
  1783.      */
  1784.     int keyint_min;
  1785.  
  1786.     /**
  1787.      * number of reference frames
  1788.      * - encoding: Set by user.
  1789.      * - decoding: Set by lavc.
  1790.      */
  1791.     int refs;
  1792.  
  1793.     /**
  1794.      * chroma qp offset from luma
  1795.      * - encoding: Set by user.
  1796.      * - decoding: unused
  1797.      */
  1798.     int chromaoffset;
  1799.  
  1800.     /**
  1801.      * Multiplied by qscale for each frame and added to scene_change_score.
  1802.      * - encoding: Set by user.
  1803.      * - decoding: unused
  1804.      */
  1805.     int scenechange_factor;
  1806.  
  1807.     /**
  1808.      *
  1809.      * Note: Value depends upon the compare function used for fullpel ME.
  1810.      * - encoding: Set by user.
  1811.      * - decoding: unused
  1812.      */
  1813.     int mv0_threshold;
  1814.  
  1815.     /**
  1816.      * Adjust sensitivity of b_frame_strategy 1.
  1817.      * - encoding: Set by user.
  1818.      * - decoding: unused
  1819.      */
  1820.     int b_sensitivity;
  1821.  
  1822.     /**
  1823.      * Chromaticity coordinates of the source primaries.
  1824.      * - encoding: Set by user
  1825.      * - decoding: Set by libavcodec
  1826.      */
  1827.     enum AVColorPrimaries color_primaries;
  1828.  
  1829.     /**
  1830.      * Color Transfer Characteristic.
  1831.      * - encoding: Set by user
  1832.      * - decoding: Set by libavcodec
  1833.      */
  1834.     enum AVColorTransferCharacteristic color_trc;
  1835.  
  1836.     /**
  1837.      * YUV colorspace type.
  1838.      * - encoding: Set by user
  1839.      * - decoding: Set by libavcodec
  1840.      */
  1841.     enum AVColorSpace colorspace;
  1842.  
  1843.     /**
  1844.      * MPEG vs JPEG YUV range.
  1845.      * - encoding: Set by user
  1846.      * - decoding: Set by libavcodec
  1847.      */
  1848.     enum AVColorRange color_range;
  1849.  
  1850.     /**
  1851.      * This defines the location of chroma samples.
  1852.      * - encoding: Set by user
  1853.      * - decoding: Set by libavcodec
  1854.      */
  1855.     enum AVChromaLocation chroma_sample_location;
  1856.  
  1857.     /**
  1858.      * Number of slices.
  1859.      * Indicates number of picture subdivisions. Used for parallelized
  1860.      * decoding.
  1861.      * - encoding: Set by user
  1862.      * - decoding: unused
  1863.      */
  1864.     int slices;
  1865.  
  1866.     /** Field order
  1867.      * - encoding: set by libavcodec
  1868.      * - decoding: Set by user.
  1869.      */
  1870.     enum AVFieldOrder field_order;
  1871.  
  1872.     /* audio only */
  1873.     int sample_rate; ///< samples per second
  1874.     int channels;    ///< number of audio channels
  1875.  
  1876.     /**
  1877.      * audio sample format
  1878.      * - encoding: Set by user.
  1879.      * - decoding: Set by libavcodec.
  1880.      */
  1881.     enum AVSampleFormat sample_fmt;  ///< sample format
  1882.  
  1883.     /* The following data should not be initialized. */
  1884.     /**
  1885.      * Number of samples per channel in an audio frame.
  1886.      *
  1887.      * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
  1888.      *   except the last must contain exactly frame_size samples per channel.
  1889.      *   May be 0 when the codec has CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
  1890.      *   frame size is not restricted.
  1891.      * - decoding: may be set by some decoders to indicate constant frame size
  1892.      */
  1893.     int frame_size;
  1894.  
  1895.     /**
  1896.      * Frame counter, set by libavcodec.
  1897.      *
  1898.      * - decoding: total number of frames returned from the decoder so far.
  1899.      * - encoding: total number of frames passed to the encoder so far.
  1900.      *
  1901.      *   @note the counter is not incremented if encoding/decoding resulted in
  1902.      *   an error.
  1903.      */
  1904.     int frame_number;
  1905.  
  1906.     /**
  1907.      * number of bytes per packet if constant and known or 0
  1908.      * Used by some WAV based audio codecs.
  1909.      */
  1910.     int block_align;
  1911.  
  1912.     /**
  1913.      * Audio cutoff bandwidth (0 means "automatic")
  1914.      * - encoding: Set by user.
  1915.      * - decoding: unused
  1916.      */
  1917.     int cutoff;
  1918.  
  1919. #if FF_API_REQUEST_CHANNELS
  1920.     /**
  1921.      * Decoder should decode to this many channels if it can (0 for default)
  1922.      * - encoding: unused
  1923.      * - decoding: Set by user.
  1924.      * @deprecated Deprecated in favor of request_channel_layout.
  1925.      */
  1926.     attribute_deprecated int request_channels;
  1927. #endif
  1928.  
  1929.     /**
  1930.      * Audio channel layout.
  1931.      * - encoding: set by user.
  1932.      * - decoding: set by user, may be overwritten by libavcodec.
  1933.      */
  1934.     uint64_t channel_layout;
  1935.  
  1936.     /**
  1937.      * Request decoder to use this channel layout if it can (0 for default)
  1938.      * - encoding: unused
  1939.      * - decoding: Set by user.
  1940.      */
  1941.     uint64_t request_channel_layout;
  1942.  
  1943.     /**
  1944.      * Type of service that the audio stream conveys.
  1945.      * - encoding: Set by user.
  1946.      * - decoding: Set by libavcodec.
  1947.      */
  1948.     enum AVAudioServiceType audio_service_type;
  1949.  
  1950.     /**
  1951.      * desired sample format
  1952.      * - encoding: Not used.
  1953.      * - decoding: Set by user.
  1954.      * Decoder will decode to this format if it can.
  1955.      */
  1956.     enum AVSampleFormat request_sample_fmt;
  1957.  
  1958. #if FF_API_GET_BUFFER
  1959.     /**
  1960.      * Called at the beginning of each frame to get a buffer for it.
  1961.      *
  1962.      * The function will set AVFrame.data[], AVFrame.linesize[].
  1963.      * AVFrame.extended_data[] must also be set, but it should be the same as
  1964.      * AVFrame.data[] except for planar audio with more channels than can fit
  1965.      * in AVFrame.data[]. In that case, AVFrame.data[] shall still contain as
  1966.      * many data pointers as it can hold.
  1967.      *
  1968.      * if CODEC_CAP_DR1 is not set then get_buffer() must call
  1969.      * avcodec_default_get_buffer() instead of providing buffers allocated by
  1970.      * some other means.
  1971.      *
  1972.      * AVFrame.data[] should be 32- or 16-byte-aligned unless the CPU doesn't
  1973.      * need it. avcodec_default_get_buffer() aligns the output buffer properly,
  1974.      * but if get_buffer() is overridden then alignment considerations should
  1975.      * be taken into account.
  1976.      *
  1977.      * @see avcodec_default_get_buffer()
  1978.      *
  1979.      * Video:
  1980.      *
  1981.      * If pic.reference is set then the frame will be read later by libavcodec.
  1982.      * avcodec_align_dimensions2() should be used to find the required width and
  1983.      * height, as they normally need to be rounded up to the next multiple of 16.
  1984.      *
  1985.      * If frame multithreading is used and thread_safe_callbacks is set,
  1986.      * it may be called from a different thread, but not from more than one at
  1987.      * once. Does not need to be reentrant.
  1988.      *
  1989.      * @see release_buffer(), reget_buffer()
  1990.      * @see avcodec_align_dimensions2()
  1991.      *
  1992.      * Audio:
  1993.      *
  1994.      * Decoders request a buffer of a particular size by setting
  1995.      * AVFrame.nb_samples prior to calling get_buffer(). The decoder may,
  1996.      * however, utilize only part of the buffer by setting AVFrame.nb_samples
  1997.      * to a smaller value in the output frame.
  1998.      *
  1999.      * Decoders cannot use the buffer after returning from
  2000.      * avcodec_decode_audio4(), so they will not call release_buffer(), as it
  2001.      * is assumed to be released immediately upon return. In some rare cases,
  2002.      * a decoder may need to call get_buffer() more than once in a single
  2003.      * call to avcodec_decode_audio4(). In that case, when get_buffer() is
  2004.      * called again after it has already been called once, the previously
  2005.      * acquired buffer is assumed to be released at that time and may not be
  2006.      * reused by the decoder.
  2007.      *
  2008.      * As a convenience, av_samples_get_buffer_size() and
  2009.      * av_samples_fill_arrays() in libavutil may be used by custom get_buffer()
  2010.      * functions to find the required data size and to fill data pointers and
  2011.      * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
  2012.      * since all planes must be the same size.
  2013.      *
  2014.      * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
  2015.      *
  2016.      * - encoding: unused
  2017.      * - decoding: Set by libavcodec, user can override.
  2018.      *
  2019.      * @deprecated use get_buffer2()
  2020.      */
  2021.     attribute_deprecated
  2022.     int (*get_buffer)(struct AVCodecContext *c, AVFrame *pic);
  2023.  
  2024.     /**
  2025.      * Called to release buffers which were allocated with get_buffer.
  2026.      * A released buffer can be reused in get_buffer().
  2027.      * pic.data[*] must be set to NULL.
  2028.      * May be called from a different thread if frame multithreading is used,
  2029.      * but not by more than one thread at once, so does not need to be reentrant.
  2030.      * - encoding: unused
  2031.      * - decoding: Set by libavcodec, user can override.
  2032.      *
  2033.      * @deprecated custom freeing callbacks should be set from get_buffer2()
  2034.      */
  2035.     attribute_deprecated
  2036.     void (*release_buffer)(struct AVCodecContext *c, AVFrame *pic);
  2037.  
  2038.     /**
  2039.      * Called at the beginning of a frame to get cr buffer for it.
  2040.      * Buffer type (size, hints) must be the same. libavcodec won't check it.
  2041.      * libavcodec will pass previous buffer in pic, function should return
  2042.      * same buffer or new buffer with old frame "painted" into it.
  2043.      * If pic.data[0] == NULL must behave like get_buffer().
  2044.      * if CODEC_CAP_DR1 is not set then reget_buffer() must call
  2045.      * avcodec_default_reget_buffer() instead of providing buffers allocated by
  2046.      * some other means.
  2047.      * - encoding: unused
  2048.      * - decoding: Set by libavcodec, user can override.
  2049.      */
  2050.     attribute_deprecated
  2051.     int (*reget_buffer)(struct AVCodecContext *c, AVFrame *pic);
  2052. #endif
  2053.  
  2054.     /**
  2055.      * This callback is called at the beginning of each frame to get data
  2056.      * buffer(s) for it. There may be one contiguous buffer for all the data or
  2057.      * there may be a buffer per each data plane or anything in between. What
  2058.      * this means is, you may set however many entries in buf[] you feel necessary.
  2059.      * Each buffer must be reference-counted using the AVBuffer API (see description
  2060.      * of buf[] below).
  2061.      *
  2062.      * The following fields will be set in the frame before this callback is
  2063.      * called:
  2064.      * - format
  2065.      * - width, height (video only)
  2066.      * - sample_rate, channel_layout, nb_samples (audio only)
  2067.      * Their values may differ from the corresponding values in
  2068.      * AVCodecContext. This callback must use the frame values, not the codec
  2069.      * context values, to calculate the required buffer size.
  2070.      *
  2071.      * This callback must fill the following fields in the frame:
  2072.      * - data[]
  2073.      * - linesize[]
  2074.      * - extended_data:
  2075.      *   * if the data is planar audio with more than 8 channels, then this
  2076.      *     callback must allocate and fill extended_data to contain all pointers
  2077.      *     to all data planes. data[] must hold as many pointers as it can.
  2078.      *     extended_data must be allocated with av_malloc() and will be freed in
  2079.      *     av_frame_unref().
  2080.      *   * otherwise exended_data must point to data
  2081.      * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
  2082.      *   the frame's data and extended_data pointers must be contained in these. That
  2083.      *   is, one AVBufferRef for each allocated chunk of memory, not necessarily one
  2084.      *   AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
  2085.      *   and av_buffer_ref().
  2086.      * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
  2087.      *   this callback and filled with the extra buffers if there are more
  2088.      *   buffers than buf[] can hold. extended_buf will be freed in
  2089.      *   av_frame_unref().
  2090.      *
  2091.      * If CODEC_CAP_DR1 is not set then get_buffer2() must call
  2092.      * avcodec_default_get_buffer2() instead of providing buffers allocated by
  2093.      * some other means.
  2094.      *
  2095.      * Each data plane must be aligned to the maximum required by the target
  2096.      * CPU.
  2097.      *
  2098.      * @see avcodec_default_get_buffer2()
  2099.      *
  2100.      * Video:
  2101.      *
  2102.      * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
  2103.      * (read and/or written to if it is writable) later by libavcodec.
  2104.      *
  2105.      * If CODEC_FLAG_EMU_EDGE is not set in s->flags, the buffer must contain an
  2106.      * edge of the size returned by avcodec_get_edge_width() on all sides.
  2107.      *
  2108.      * avcodec_align_dimensions2() should be used to find the required width and
  2109.      * height, as they normally need to be rounded up to the next multiple of 16.
  2110.      *
  2111.      * If frame multithreading is used and thread_safe_callbacks is set,
  2112.      * this callback may be called from a different thread, but not from more
  2113.      * than one at once. Does not need to be reentrant.
  2114.      *
  2115.      * @see avcodec_align_dimensions2()
  2116.      *
  2117.      * Audio:
  2118.      *
  2119.      * Decoders request a buffer of a particular size by setting
  2120.      * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
  2121.      * however, utilize only part of the buffer by setting AVFrame.nb_samples
  2122.      * to a smaller value in the output frame.
  2123.      *
  2124.      * As a convenience, av_samples_get_buffer_size() and
  2125.      * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
  2126.      * functions to find the required data size and to fill data pointers and
  2127.      * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
  2128.      * since all planes must be the same size.
  2129.      *
  2130.      * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
  2131.      *
  2132.      * - encoding: unused
  2133.      * - decoding: Set by libavcodec, user can override.
  2134.      */
  2135.     int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
  2136.  
  2137.     /**
  2138.      * If non-zero, the decoded audio and video frames returned from
  2139.      * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
  2140.      * and are valid indefinitely. The caller must free them with
  2141.      * av_frame_unref() when they are not needed anymore.
  2142.      * Otherwise, the decoded frames must not be freed by the caller and are
  2143.      * only valid until the next decode call.
  2144.      *
  2145.      * - encoding: unused
  2146.      * - decoding: set by the caller before avcodec_open2().
  2147.      */
  2148.     int refcounted_frames;
  2149.  
  2150.     /* - encoding parameters */
  2151.     float qcompress;  ///< amount of qscale change between easy & hard scenes (0.0-1.0)
  2152.     float qblur;      ///< amount of qscale smoothing over time (0.0-1.0)
  2153.  
  2154.     /**
  2155.      * minimum quantizer
  2156.      * - encoding: Set by user.
  2157.      * - decoding: unused
  2158.      */
  2159.     int qmin;
  2160.  
  2161.     /**
  2162.      * maximum quantizer
  2163.      * - encoding: Set by user.
  2164.      * - decoding: unused
  2165.      */
  2166.     int qmax;
  2167.  
  2168.     /**
  2169.      * maximum quantizer difference between frames
  2170.      * - encoding: Set by user.
  2171.      * - decoding: unused
  2172.      */
  2173.     int max_qdiff;
  2174.  
  2175.     /**
  2176.      * ratecontrol qmin qmax limiting method
  2177.      * 0-> clipping, 1-> use a nice continuous function to limit qscale wthin qmin/qmax.
  2178.      * - encoding: Set by user.
  2179.      * - decoding: unused
  2180.      */
  2181.     float rc_qsquish;
  2182.  
  2183.     float rc_qmod_amp;
  2184.     int rc_qmod_freq;
  2185.  
  2186.     /**
  2187.      * decoder bitstream buffer size
  2188.      * - encoding: Set by user.
  2189.      * - decoding: unused
  2190.      */
  2191.     int rc_buffer_size;
  2192.  
  2193.     /**
  2194.      * ratecontrol override, see RcOverride
  2195.      * - encoding: Allocated/set/freed by user.
  2196.      * - decoding: unused
  2197.      */
  2198.     int rc_override_count;
  2199.     RcOverride *rc_override;
  2200.  
  2201.     /**
  2202.      * rate control equation
  2203.      * - encoding: Set by user
  2204.      * - decoding: unused
  2205.      */
  2206.     const char *rc_eq;
  2207.  
  2208.     /**
  2209.      * maximum bitrate
  2210.      * - encoding: Set by user.
  2211.      * - decoding: unused
  2212.      */
  2213.     int rc_max_rate;
  2214.  
  2215.     /**
  2216.      * minimum bitrate
  2217.      * - encoding: Set by user.
  2218.      * - decoding: unused
  2219.      */
  2220.     int rc_min_rate;
  2221.  
  2222.     float rc_buffer_aggressivity;
  2223.  
  2224.     /**
  2225.      * initial complexity for pass1 ratecontrol
  2226.      * - encoding: Set by user.
  2227.      * - decoding: unused
  2228.      */
  2229.     float rc_initial_cplx;
  2230.  
  2231.     /**
  2232.      * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
  2233.      * - encoding: Set by user.
  2234.      * - decoding: unused.
  2235.      */
  2236.     float rc_max_available_vbv_use;
  2237.  
  2238.     /**
  2239.      * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
  2240.      * - encoding: Set by user.
  2241.      * - decoding: unused.
  2242.      */
  2243.     float rc_min_vbv_overflow_use;
  2244.  
  2245.     /**
  2246.      * Number of bits which should be loaded into the rc buffer before decoding starts.
  2247.      * - encoding: Set by user.
  2248.      * - decoding: unused
  2249.      */
  2250.     int rc_initial_buffer_occupancy;
  2251.  
  2252. #define FF_CODER_TYPE_VLC       0
  2253. #define FF_CODER_TYPE_AC        1
  2254. #define FF_CODER_TYPE_RAW       2
  2255. #define FF_CODER_TYPE_RLE       3
  2256. #define FF_CODER_TYPE_DEFLATE   4
  2257.     /**
  2258.      * coder type
  2259.      * - encoding: Set by user.
  2260.      * - decoding: unused
  2261.      */
  2262.     int coder_type;
  2263.  
  2264.     /**
  2265.      * context model
  2266.      * - encoding: Set by user.
  2267.      * - decoding: unused
  2268.      */
  2269.     int context_model;
  2270.  
  2271.     /**
  2272.      * minimum Lagrange multipler
  2273.      * - encoding: Set by user.
  2274.      * - decoding: unused
  2275.      */
  2276.     int lmin;
  2277.  
  2278.     /**
  2279.      * maximum Lagrange multipler
  2280.      * - encoding: Set by user.
  2281.      * - decoding: unused
  2282.      */
  2283.     int lmax;
  2284.  
  2285.     /**
  2286.      * frame skip threshold
  2287.      * - encoding: Set by user.
  2288.      * - decoding: unused
  2289.      */
  2290.     int frame_skip_threshold;
  2291.  
  2292.     /**
  2293.      * frame skip factor
  2294.      * - encoding: Set by user.
  2295.      * - decoding: unused
  2296.      */
  2297.     int frame_skip_factor;
  2298.  
  2299.     /**
  2300.      * frame skip exponent
  2301.      * - encoding: Set by user.
  2302.      * - decoding: unused
  2303.      */
  2304.     int frame_skip_exp;
  2305.  
  2306.     /**
  2307.      * frame skip comparison function
  2308.      * - encoding: Set by user.
  2309.      * - decoding: unused
  2310.      */
  2311.     int frame_skip_cmp;
  2312.  
  2313.     /**
  2314.      * trellis RD quantization
  2315.      * - encoding: Set by user.
  2316.      * - decoding: unused
  2317.      */
  2318.     int trellis;
  2319.  
  2320.     /**
  2321.      * - encoding: Set by user.
  2322.      * - decoding: unused
  2323.      */
  2324.     int min_prediction_order;
  2325.  
  2326.     /**
  2327.      * - encoding: Set by user.
  2328.      * - decoding: unused
  2329.      */
  2330.     int max_prediction_order;
  2331.  
  2332.     /**
  2333.      * GOP timecode frame start number
  2334.      * - encoding: Set by user, in non drop frame format
  2335.      * - decoding: Set by libavcodec (timecode in the 25 bits format, -1 if unset)
  2336.      */
  2337.     int64_t timecode_frame_start;
  2338.  
  2339.     /* The RTP callback: This function is called    */
  2340.     /* every time the encoder has a packet to send. */
  2341.     /* It depends on the encoder if the data starts */
  2342.     /* with a Start Code (it should). H.263 does.   */
  2343.     /* mb_nb contains the number of macroblocks     */
  2344.     /* encoded in the RTP payload.                  */
  2345.     void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
  2346.  
  2347.     int rtp_payload_size;   /* The size of the RTP payload: the coder will  */
  2348.                             /* do its best to deliver a chunk with size     */
  2349.                             /* below rtp_payload_size, the chunk will start */
  2350.                             /* with a start code on some codecs like H.263. */
  2351.                             /* This doesn't take account of any particular  */
  2352.                             /* headers inside the transmitted RTP payload.  */
  2353.  
  2354.     /* statistics, used for 2-pass encoding */
  2355.     int mv_bits;
  2356.     int header_bits;
  2357.     int i_tex_bits;
  2358.     int p_tex_bits;
  2359.     int i_count;
  2360.     int p_count;
  2361.     int skip_count;
  2362.     int misc_bits;
  2363.  
  2364.     /**
  2365.      * number of bits used for the previously encoded frame
  2366.      * - encoding: Set by libavcodec.
  2367.      * - decoding: unused
  2368.      */
  2369.     int frame_bits;
  2370.  
  2371.     /**
  2372.      * pass1 encoding statistics output buffer
  2373.      * - encoding: Set by libavcodec.
  2374.      * - decoding: unused
  2375.      */
  2376.     char *stats_out;
  2377.  
  2378.     /**
  2379.      * pass2 encoding statistics input buffer
  2380.      * Concatenated stuff from stats_out of pass1 should be placed here.
  2381.      * - encoding: Allocated/set/freed by user.
  2382.      * - decoding: unused
  2383.      */
  2384.     char *stats_in;
  2385.  
  2386.     /**
  2387.      * Work around bugs in encoders which sometimes cannot be detected automatically.
  2388.      * - encoding: Set by user
  2389.      * - decoding: Set by user
  2390.      */
  2391.     int workaround_bugs;
  2392. #define FF_BUG_AUTODETECT       1  ///< autodetection
  2393. #define FF_BUG_OLD_MSMPEG4      2
  2394. #define FF_BUG_XVID_ILACE       4
  2395. #define FF_BUG_UMP4             8
  2396. #define FF_BUG_NO_PADDING       16
  2397. #define FF_BUG_AMV              32
  2398. #define FF_BUG_AC_VLC           0  ///< Will be removed, libavcodec can now handle these non-compliant files by default.
  2399. #define FF_BUG_QPEL_CHROMA      64
  2400. #define FF_BUG_STD_QPEL         128
  2401. #define FF_BUG_QPEL_CHROMA2     256
  2402. #define FF_BUG_DIRECT_BLOCKSIZE 512
  2403. #define FF_BUG_EDGE             1024
  2404. #define FF_BUG_HPEL_CHROMA      2048
  2405. #define FF_BUG_DC_CLIP          4096
  2406. #define FF_BUG_MS               8192 ///< Work around various bugs in Microsoft's broken decoders.
  2407. #define FF_BUG_TRUNCATED       16384
  2408.  
  2409.     /**
  2410.      * strictly follow the standard (MPEG4, ...).
  2411.      * - encoding: Set by user.
  2412.      * - decoding: Set by user.
  2413.      * Setting this to STRICT or higher means the encoder and decoder will
  2414.      * generally do stupid things, whereas setting it to unofficial or lower
  2415.      * will mean the encoder might produce output that is not supported by all
  2416.      * spec-compliant decoders. Decoders don't differentiate between normal,
  2417.      * unofficial and experimental (that is, they always try to decode things
  2418.      * when they can) unless they are explicitly asked to behave stupidly
  2419.      * (=strictly conform to the specs)
  2420.      */
  2421.     int strict_std_compliance;
  2422. #define FF_COMPLIANCE_VERY_STRICT   2 ///< Strictly conform to an older more strict version of the spec or reference software.
  2423. #define FF_COMPLIANCE_STRICT        1 ///< Strictly conform to all the things in the spec no matter what consequences.
  2424. #define FF_COMPLIANCE_NORMAL        0
  2425. #define FF_COMPLIANCE_UNOFFICIAL   -1 ///< Allow unofficial extensions
  2426. #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
  2427.  
  2428.     /**
  2429.      * error concealment flags
  2430.      * - encoding: unused
  2431.      * - decoding: Set by user.
  2432.      */
  2433.     int error_concealment;
  2434. #define FF_EC_GUESS_MVS   1
  2435. #define FF_EC_DEBLOCK     2
  2436.  
  2437.     /**
  2438.      * debug
  2439.      * - encoding: Set by user.
  2440.      * - decoding: Set by user.
  2441.      */
  2442.     int debug;
  2443. #define FF_DEBUG_PICT_INFO   1
  2444. #define FF_DEBUG_RC          2
  2445. #define FF_DEBUG_BITSTREAM   4
  2446. #define FF_DEBUG_MB_TYPE     8
  2447. #define FF_DEBUG_QP          16
  2448. #define FF_DEBUG_MV          32
  2449. #define FF_DEBUG_DCT_COEFF   0x00000040
  2450. #define FF_DEBUG_SKIP        0x00000080
  2451. #define FF_DEBUG_STARTCODE   0x00000100
  2452. #define FF_DEBUG_PTS         0x00000200
  2453. #define FF_DEBUG_ER          0x00000400
  2454. #define FF_DEBUG_MMCO        0x00000800
  2455. #define FF_DEBUG_BUGS        0x00001000
  2456. #define FF_DEBUG_VIS_QP      0x00002000
  2457. #define FF_DEBUG_VIS_MB_TYPE 0x00004000
  2458. #define FF_DEBUG_BUFFERS     0x00008000
  2459. #define FF_DEBUG_THREADS     0x00010000
  2460.  
  2461.     /**
  2462.      * debug
  2463.      * - encoding: Set by user.
  2464.      * - decoding: Set by user.
  2465.      */
  2466.     int debug_mv;
  2467. #define FF_DEBUG_VIS_MV_P_FOR  0x00000001 //visualize forward predicted MVs of P frames
  2468. #define FF_DEBUG_VIS_MV_B_FOR  0x00000002 //visualize forward predicted MVs of B frames
  2469. #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
  2470.  
  2471.     /**
  2472.      * Error recognition; may misdetect some more or less valid parts as errors.
  2473.      * - encoding: unused
  2474.      * - decoding: Set by user.
  2475.      */
  2476.     int err_recognition;
  2477. #define AV_EF_CRCCHECK  (1<<0)          ///< verify embedded CRCs
  2478. #define AV_EF_BITSTREAM (1<<1)          ///< detect bitstream specification deviations
  2479. #define AV_EF_BUFFER    (1<<2)          ///< detect improper bitstream length
  2480. #define AV_EF_EXPLODE   (1<<3)          ///< abort decoding on minor error detection
  2481.  
  2482. #define AV_EF_CAREFUL    (1<<16)        ///< consider things that violate the spec, are fast to calculate and have not been seen in the wild as errors
  2483. #define AV_EF_COMPLIANT  (1<<17)        ///< consider all spec non compliancies as errors
  2484. #define AV_EF_AGGRESSIVE (1<<18)        ///< consider things that a sane encoder should not do as an error
  2485.  
  2486.  
  2487.     /**
  2488.      * opaque 64bit number (generally a PTS) that will be reordered and
  2489.      * output in AVFrame.reordered_opaque
  2490.      * @deprecated in favor of pkt_pts
  2491.      * - encoding: unused
  2492.      * - decoding: Set by user.
  2493.      */
  2494.     int64_t reordered_opaque;
  2495.  
  2496.     /**
  2497.      * Hardware accelerator in use
  2498.      * - encoding: unused.
  2499.      * - decoding: Set by libavcodec
  2500.      */
  2501.     struct AVHWAccel *hwaccel;
  2502.  
  2503.     /**
  2504.      * Hardware accelerator context.
  2505.      * For some hardware accelerators, a global context needs to be
  2506.      * provided by the user. In that case, this holds display-dependent
  2507.      * data FFmpeg cannot instantiate itself. Please refer to the
  2508.      * FFmpeg HW accelerator documentation to know how to fill this
  2509.      * is. e.g. for VA API, this is a struct vaapi_context.
  2510.      * - encoding: unused
  2511.      * - decoding: Set by user
  2512.      */
  2513.     void *hwaccel_context;
  2514.  
  2515.     /**
  2516.      * error
  2517.      * - encoding: Set by libavcodec if flags&CODEC_FLAG_PSNR.
  2518.      * - decoding: unused
  2519.      */
  2520.     uint64_t error[AV_NUM_DATA_POINTERS];
  2521.  
  2522.     /**
  2523.      * DCT algorithm, see FF_DCT_* below
  2524.      * - encoding: Set by user.
  2525.      * - decoding: unused
  2526.      */
  2527.     int dct_algo;
  2528. #define FF_DCT_AUTO    0
  2529. #define FF_DCT_FASTINT 1
  2530. #define FF_DCT_INT     2
  2531. #define FF_DCT_MMX     3
  2532. #define FF_DCT_ALTIVEC 5
  2533. #define FF_DCT_FAAN    6
  2534.  
  2535.     /**
  2536.      * IDCT algorithm, see FF_IDCT_* below.
  2537.      * - encoding: Set by user.
  2538.      * - decoding: Set by user.
  2539.      */
  2540.     int idct_algo;
  2541. #define FF_IDCT_AUTO          0
  2542. #define FF_IDCT_INT           1
  2543. #define FF_IDCT_SIMPLE        2
  2544. #define FF_IDCT_SIMPLEMMX     3
  2545. #define FF_IDCT_ARM           7
  2546. #define FF_IDCT_ALTIVEC       8
  2547. #define FF_IDCT_SH4           9
  2548. #define FF_IDCT_SIMPLEARM     10
  2549. #define FF_IDCT_IPP           13
  2550. #define FF_IDCT_XVIDMMX       14
  2551. #define FF_IDCT_SIMPLEARMV5TE 16
  2552. #define FF_IDCT_SIMPLEARMV6   17
  2553. #define FF_IDCT_SIMPLEVIS     18
  2554. #define FF_IDCT_FAAN          20
  2555. #define FF_IDCT_SIMPLENEON    22
  2556. #define FF_IDCT_SIMPLEALPHA   23
  2557.  
  2558.     /**
  2559.      * bits per sample/pixel from the demuxer (needed for huffyuv).
  2560.      * - encoding: Set by libavcodec.
  2561.      * - decoding: Set by user.
  2562.      */
  2563.      int bits_per_coded_sample;
  2564.  
  2565.     /**
  2566.      * Bits per sample/pixel of internal libavcodec pixel/sample format.
  2567.      * - encoding: set by user.
  2568.      * - decoding: set by libavcodec.
  2569.      */
  2570.     int bits_per_raw_sample;
  2571.  
  2572. #if FF_API_LOWRES
  2573.     /**
  2574.      * low resolution decoding, 1-> 1/2 size, 2->1/4 size
  2575.      * - encoding: unused
  2576.      * - decoding: Set by user.
  2577.      * Code outside libavcodec should access this field using:
  2578.      * av_codec_{get,set}_lowres(avctx)
  2579.      */
  2580.      int lowres;
  2581. #endif
  2582.  
  2583.     /**
  2584.      * the picture in the bitstream
  2585.      * - encoding: Set by libavcodec.
  2586.      * - decoding: Set by libavcodec.
  2587.      */
  2588.     AVFrame *coded_frame;
  2589.  
  2590.     /**
  2591.      * thread count
  2592.      * is used to decide how many independent tasks should be passed to execute()
  2593.      * - encoding: Set by user.
  2594.      * - decoding: Set by user.
  2595.      */
  2596.     int thread_count;
  2597.  
  2598.     /**
  2599.      * Which multithreading methods to use.
  2600.      * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
  2601.      * so clients which cannot provide future frames should not use it.
  2602.      *
  2603.      * - encoding: Set by user, otherwise the default is used.
  2604.      * - decoding: Set by user, otherwise the default is used.
  2605.      */
  2606.     int thread_type;
  2607. #define FF_THREAD_FRAME   1 ///< Decode more than one frame at once
  2608. #define FF_THREAD_SLICE   2 ///< Decode more than one part of a single frame at once
  2609.  
  2610.     /**
  2611.      * Which multithreading methods are in use by the codec.
  2612.      * - encoding: Set by libavcodec.
  2613.      * - decoding: Set by libavcodec.
  2614.      */
  2615.     int active_thread_type;
  2616.  
  2617.     /**
  2618.      * Set by the client if its custom get_buffer() callback can be called
  2619.      * synchronously from another thread, which allows faster multithreaded decoding.
  2620.      * draw_horiz_band() will be called from other threads regardless of this setting.
  2621.      * Ignored if the default get_buffer() is used.
  2622.      * - encoding: Set by user.
  2623.      * - decoding: Set by user.
  2624.      */
  2625.     int thread_safe_callbacks;
  2626.  
  2627.     /**
  2628.      * The codec may call this to execute several independent things.
  2629.      * It will return only after finishing all tasks.
  2630.      * The user may replace this with some multithreaded implementation,
  2631.      * the default implementation will execute the parts serially.
  2632.      * @param count the number of things to execute
  2633.      * - encoding: Set by libavcodec, user can override.
  2634.      * - decoding: Set by libavcodec, user can override.
  2635.      */
  2636.     int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
  2637.  
  2638.     /**
  2639.      * The codec may call this to execute several independent things.
  2640.      * It will return only after finishing all tasks.
  2641.      * The user may replace this with some multithreaded implementation,
  2642.      * the default implementation will execute the parts serially.
  2643.      * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
  2644.      * @param c context passed also to func
  2645.      * @param count the number of things to execute
  2646.      * @param arg2 argument passed unchanged to func
  2647.      * @param ret return values of executed functions, must have space for "count" values. May be NULL.
  2648.      * @param func function that will be called count times, with jobnr from 0 to count-1.
  2649.      *             threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
  2650.      *             two instances of func executing at the same time will have the same threadnr.
  2651.      * @return always 0 currently, but code should handle a future improvement where when any call to func
  2652.      *         returns < 0 no further calls to func may be done and < 0 is returned.
  2653.      * - encoding: Set by libavcodec, user can override.
  2654.      * - decoding: Set by libavcodec, user can override.
  2655.      */
  2656.     int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
  2657.  
  2658.     /**
  2659.      * thread opaque
  2660.      * Can be used by execute() to store some per AVCodecContext stuff.
  2661.      * - encoding: set by execute()
  2662.      * - decoding: set by execute()
  2663.      */
  2664.     void *thread_opaque;
  2665.  
  2666.     /**
  2667.      * noise vs. sse weight for the nsse comparsion function
  2668.      * - encoding: Set by user.
  2669.      * - decoding: unused
  2670.      */
  2671.      int nsse_weight;
  2672.  
  2673.     /**
  2674.      * profile
  2675.      * - encoding: Set by user.
  2676.      * - decoding: Set by libavcodec.
  2677.      */
  2678.      int profile;
  2679. #define FF_PROFILE_UNKNOWN -99
  2680. #define FF_PROFILE_RESERVED -100
  2681.  
  2682. #define FF_PROFILE_AAC_MAIN 0
  2683. #define FF_PROFILE_AAC_LOW  1
  2684. #define FF_PROFILE_AAC_SSR  2
  2685. #define FF_PROFILE_AAC_LTP  3
  2686. #define FF_PROFILE_AAC_HE   4
  2687. #define FF_PROFILE_AAC_HE_V2 28
  2688. #define FF_PROFILE_AAC_LD   22
  2689. #define FF_PROFILE_AAC_ELD  38
  2690. #define FF_PROFILE_MPEG2_AAC_LOW 128
  2691. #define FF_PROFILE_MPEG2_AAC_HE  131
  2692.  
  2693. #define FF_PROFILE_DTS         20
  2694. #define FF_PROFILE_DTS_ES      30
  2695. #define FF_PROFILE_DTS_96_24   40
  2696. #define FF_PROFILE_DTS_HD_HRA  50
  2697. #define FF_PROFILE_DTS_HD_MA   60
  2698.  
  2699. #define FF_PROFILE_MPEG2_422    0
  2700. #define FF_PROFILE_MPEG2_HIGH   1
  2701. #define FF_PROFILE_MPEG2_SS     2
  2702. #define FF_PROFILE_MPEG2_SNR_SCALABLE  3
  2703. #define FF_PROFILE_MPEG2_MAIN   4
  2704. #define FF_PROFILE_MPEG2_SIMPLE 5
  2705.  
  2706. #define FF_PROFILE_H264_CONSTRAINED  (1<<9)  // 8+1; constraint_set1_flag
  2707. #define FF_PROFILE_H264_INTRA        (1<<11) // 8+3; constraint_set3_flag
  2708.  
  2709. #define FF_PROFILE_H264_BASELINE             66
  2710. #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
  2711. #define FF_PROFILE_H264_MAIN                 77
  2712. #define FF_PROFILE_H264_EXTENDED             88
  2713. #define FF_PROFILE_H264_HIGH                 100
  2714. #define FF_PROFILE_H264_HIGH_10              110
  2715. #define FF_PROFILE_H264_HIGH_10_INTRA        (110|FF_PROFILE_H264_INTRA)
  2716. #define FF_PROFILE_H264_HIGH_422             122
  2717. #define FF_PROFILE_H264_HIGH_422_INTRA       (122|FF_PROFILE_H264_INTRA)
  2718. #define FF_PROFILE_H264_HIGH_444             144
  2719. #define FF_PROFILE_H264_HIGH_444_PREDICTIVE  244
  2720. #define FF_PROFILE_H264_HIGH_444_INTRA       (244|FF_PROFILE_H264_INTRA)
  2721. #define FF_PROFILE_H264_CAVLC_444            44
  2722.  
  2723. #define FF_PROFILE_VC1_SIMPLE   0
  2724. #define FF_PROFILE_VC1_MAIN     1
  2725. #define FF_PROFILE_VC1_COMPLEX  2
  2726. #define FF_PROFILE_VC1_ADVANCED 3
  2727.  
  2728. #define FF_PROFILE_MPEG4_SIMPLE                     0
  2729. #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE            1
  2730. #define FF_PROFILE_MPEG4_CORE                       2
  2731. #define FF_PROFILE_MPEG4_MAIN                       3
  2732. #define FF_PROFILE_MPEG4_N_BIT                      4
  2733. #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE           5
  2734. #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION      6
  2735. #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE     7
  2736. #define FF_PROFILE_MPEG4_HYBRID                     8
  2737. #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME         9
  2738. #define FF_PROFILE_MPEG4_CORE_SCALABLE             10
  2739. #define FF_PROFILE_MPEG4_ADVANCED_CODING           11
  2740. #define FF_PROFILE_MPEG4_ADVANCED_CORE             12
  2741. #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
  2742. #define FF_PROFILE_MPEG4_SIMPLE_STUDIO             14
  2743. #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE           15
  2744.  
  2745. #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0   0
  2746. #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1   1
  2747. #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION  2
  2748. #define FF_PROFILE_JPEG2000_DCINEMA_2K              3
  2749. #define FF_PROFILE_JPEG2000_DCINEMA_4K              4
  2750.  
  2751.     /**
  2752.      * level
  2753.      * - encoding: Set by user.
  2754.      * - decoding: Set by libavcodec.
  2755.      */
  2756.      int level;
  2757. #define FF_LEVEL_UNKNOWN -99
  2758.  
  2759.     /**
  2760.      * Skip loop filtering for selected frames.
  2761.      * - encoding: unused
  2762.      * - decoding: Set by user.
  2763.      */
  2764.     enum AVDiscard skip_loop_filter;
  2765.  
  2766.     /**
  2767.      * Skip IDCT/dequantization for selected frames.
  2768.      * - encoding: unused
  2769.      * - decoding: Set by user.
  2770.      */
  2771.     enum AVDiscard skip_idct;
  2772.  
  2773.     /**
  2774.      * Skip decoding for selected frames.
  2775.      * - encoding: unused
  2776.      * - decoding: Set by user.
  2777.      */
  2778.     enum AVDiscard skip_frame;
  2779.  
  2780.     /**
  2781.      * Header containing style information for text subtitles.
  2782.      * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
  2783.      * [Script Info] and [V4+ Styles] section, plus the [Events] line and
  2784.      * the Format line following. It shouldn't include any Dialogue line.
  2785.      * - encoding: Set/allocated/freed by user (before avcodec_open2())
  2786.      * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
  2787.      */
  2788.     uint8_t *subtitle_header;
  2789.     int subtitle_header_size;
  2790.  
  2791.     /**
  2792.      * Simulates errors in the bitstream to test error concealment.
  2793.      * - encoding: Set by user.
  2794.      * - decoding: unused
  2795.      */
  2796.     int error_rate;
  2797.  
  2798.     /**
  2799.      * Current packet as passed into the decoder, to avoid having
  2800.      * to pass the packet into every function. Currently only valid
  2801.      * inside lavc and get/release_buffer callbacks.
  2802.      * - decoding: set by avcodec_decode_*, read by get_buffer() for setting pkt_pts
  2803.      * - encoding: unused
  2804.      */
  2805.     AVPacket *pkt;
  2806.  
  2807.     /**
  2808.      * VBV delay coded in the last frame (in periods of a 27 MHz clock).
  2809.      * Used for compliant TS muxing.
  2810.      * - encoding: Set by libavcodec.
  2811.      * - decoding: unused.
  2812.      */
  2813.     uint64_t vbv_delay;
  2814.  
  2815.     /**
  2816.      * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
  2817.      * Code outside libavcodec should access this field using:
  2818.      * av_codec_{get,set}_pkt_timebase(avctx)
  2819.      * - encoding unused.
  2820.      * - decoding set by user.
  2821.      */
  2822.     AVRational pkt_timebase;
  2823.  
  2824.     /**
  2825.      * AVCodecDescriptor
  2826.      * Code outside libavcodec should access this field using:
  2827.      * av_codec_{get,set}_codec_descriptor(avctx)
  2828.      * - encoding: unused.
  2829.      * - decoding: set by libavcodec.
  2830.      */
  2831.     const AVCodecDescriptor *codec_descriptor;
  2832.  
  2833. #if !FF_API_LOWRES
  2834.     /**
  2835.      * low resolution decoding, 1-> 1/2 size, 2->1/4 size
  2836.      * - encoding: unused
  2837.      * - decoding: Set by user.
  2838.      * Code outside libavcodec should access this field using:
  2839.      * av_codec_{get,set}_lowres(avctx)
  2840.      */
  2841.      int lowres;
  2842. #endif
  2843.  
  2844.     /**
  2845.      * Current statistics for PTS correction.
  2846.      * - decoding: maintained and used by libavcodec, not intended to be used by user apps
  2847.      * - encoding: unused
  2848.      */
  2849.     int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
  2850.     int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
  2851.     int64_t pts_correction_last_pts;       /// PTS of the last frame
  2852.     int64_t pts_correction_last_dts;       /// DTS of the last frame
  2853.  
  2854.     /**
  2855.      * Character encoding of the input subtitles file.
  2856.      * - decoding: set by user
  2857.      * - encoding: unused
  2858.      */
  2859.     char *sub_charenc;
  2860.  
  2861.     /**
  2862.      * Subtitles character encoding mode. Formats or codecs might be adjusting
  2863.      * this setting (if they are doing the conversion themselves for instance).
  2864.      * - decoding: set by libavcodec
  2865.      * - encoding: unused
  2866.      */
  2867.     int sub_charenc_mode;
  2868. #define FF_SUB_CHARENC_MODE_DO_NOTHING  -1  ///< do nothing (demuxer outputs a stream supposed to be already in UTF-8, or the codec is bitmap for instance)
  2869. #define FF_SUB_CHARENC_MODE_AUTOMATIC    0  ///< libavcodec will select the mode itself
  2870. #define FF_SUB_CHARENC_MODE_PRE_DECODER  1  ///< the AVPacket data needs to be recoded to UTF-8 before being fed to the decoder, requires iconv
  2871.  
  2872.     /**
  2873.      * Skip processing alpha if supported by codec.
  2874.      * Note that if the format uses pre-multiplied alpha (common with VP6,
  2875.      * and recommended due to better video quality/compression)
  2876.      * the image will look as if alpha-blended onto a black background.
  2877.      * However for formats that do not use pre-multiplied alpha
  2878.      * there might be serious artefacts (though e.g. libswscale currently
  2879.      * assumes pre-multiplied alpha anyway).
  2880.      * Code outside libavcodec should access this field using AVOptions
  2881.      *
  2882.      * - decoding: set by user
  2883.      * - encoding: unused
  2884.      */
  2885.     int skip_alpha;
  2886.  
  2887.     /**
  2888.      * Number of samples to skip after a discontinuity
  2889.      * - decoding: unused
  2890.      * - encoding: set by libavcodec
  2891.      */
  2892.     int seek_preroll;
  2893. } AVCodecContext;
  2894.  
  2895. AVRational av_codec_get_pkt_timebase         (const AVCodecContext *avctx);
  2896. void       av_codec_set_pkt_timebase         (AVCodecContext *avctx, AVRational val);
  2897.  
  2898. const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
  2899. void                     av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
  2900.  
  2901. int  av_codec_get_lowres(const AVCodecContext *avctx);
  2902. void av_codec_set_lowres(AVCodecContext *avctx, int val);
  2903.  
  2904. int  av_codec_get_seek_preroll(const AVCodecContext *avctx);
  2905. void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
  2906.  
  2907. /**
  2908.  * AVProfile.
  2909.  */
  2910. typedef struct AVProfile {
  2911.     int profile;
  2912.     const char *name; ///< short name for the profile
  2913. } AVProfile;
  2914.  
  2915. typedef struct AVCodecDefault AVCodecDefault;
  2916.  
  2917. struct AVSubtitle;
  2918.  
  2919. /**
  2920.  * AVCodec.
  2921.  */
  2922. typedef struct AVCodec {
  2923.     /**
  2924.      * Name of the codec implementation.
  2925.      * The name is globally unique among encoders and among decoders (but an
  2926.      * encoder and a decoder can share the same name).
  2927.      * This is the primary way to find a codec from the user perspective.
  2928.      */
  2929.     const char *name;
  2930.     /**
  2931.      * Descriptive name for the codec, meant to be more human readable than name.
  2932.      * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
  2933.      */
  2934.     const char *long_name;
  2935.     enum AVMediaType type;
  2936.     enum AVCodecID id;
  2937.     /**
  2938.      * Codec capabilities.
  2939.      * see CODEC_CAP_*
  2940.      */
  2941.     int capabilities;
  2942.     const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
  2943.     const enum AVPixelFormat *pix_fmts;     ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
  2944.     const int *supported_samplerates;       ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
  2945.     const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
  2946.     const uint64_t *channel_layouts;         ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
  2947. #if FF_API_LOWRES
  2948.     uint8_t max_lowres;                     ///< maximum value for lowres supported by the decoder, no direct access, use av_codec_get_max_lowres()
  2949. #endif
  2950.     const AVClass *priv_class;              ///< AVClass for the private context
  2951.     const AVProfile *profiles;              ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
  2952.  
  2953.     /*****************************************************************
  2954.      * No fields below this line are part of the public API. They
  2955.      * may not be used outside of libavcodec and can be changed and
  2956.      * removed at will.
  2957.      * New public fields should be added right above.
  2958.      *****************************************************************
  2959.      */
  2960.     int priv_data_size;
  2961.     struct AVCodec *next;
  2962.     /**
  2963.      * @name Frame-level threading support functions
  2964.      * @{
  2965.      */
  2966.     /**
  2967.      * If defined, called on thread contexts when they are created.
  2968.      * If the codec allocates writable tables in init(), re-allocate them here.
  2969.      * priv_data will be set to a copy of the original.
  2970.      */
  2971.     int (*init_thread_copy)(AVCodecContext *);
  2972.     /**
  2973.      * Copy necessary context variables from a previous thread context to the current one.
  2974.      * If not defined, the next thread will start automatically; otherwise, the codec
  2975.      * must call ff_thread_finish_setup().
  2976.      *
  2977.      * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
  2978.      */
  2979.     int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
  2980.     /** @} */
  2981.  
  2982.     /**
  2983.      * Private codec-specific defaults.
  2984.      */
  2985.     const AVCodecDefault *defaults;
  2986.  
  2987.     /**
  2988.      * Initialize codec static data, called from avcodec_register().
  2989.      */
  2990.     void (*init_static_data)(struct AVCodec *codec);
  2991.  
  2992.     int (*init)(AVCodecContext *);
  2993.     int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
  2994.                       const struct AVSubtitle *sub);
  2995.     /**
  2996.      * Encode data to an AVPacket.
  2997.      *
  2998.      * @param      avctx          codec context
  2999.      * @param      avpkt          output AVPacket (may contain a user-provided buffer)
  3000.      * @param[in]  frame          AVFrame containing the raw data to be encoded
  3001.      * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
  3002.      *                            non-empty packet was returned in avpkt.
  3003.      * @return 0 on success, negative error code on failure
  3004.      */
  3005.     int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
  3006.                    int *got_packet_ptr);
  3007.     int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
  3008.     int (*close)(AVCodecContext *);
  3009.     /**
  3010.      * Flush buffers.
  3011.      * Will be called when seeking
  3012.      */
  3013.     void (*flush)(AVCodecContext *);
  3014. } AVCodec;
  3015.  
  3016. int av_codec_get_max_lowres(const AVCodec *codec);
  3017.  
  3018. /**
  3019.  * AVHWAccel.
  3020.  */
  3021. typedef struct AVHWAccel {
  3022.     /**
  3023.      * Name of the hardware accelerated codec.
  3024.      * The name is globally unique among encoders and among decoders (but an
  3025.      * encoder and a decoder can share the same name).
  3026.      */
  3027.     const char *name;
  3028.  
  3029.     /**
  3030.      * Type of codec implemented by the hardware accelerator.
  3031.      *
  3032.      * See AVMEDIA_TYPE_xxx
  3033.      */
  3034.     enum AVMediaType type;
  3035.  
  3036.     /**
  3037.      * Codec implemented by the hardware accelerator.
  3038.      *
  3039.      * See AV_CODEC_ID_xxx
  3040.      */
  3041.     enum AVCodecID id;
  3042.  
  3043.     /**
  3044.      * Supported pixel format.
  3045.      *
  3046.      * Only hardware accelerated formats are supported here.
  3047.      */
  3048.     enum AVPixelFormat pix_fmt;
  3049.  
  3050.     /**
  3051.      * Hardware accelerated codec capabilities.
  3052.      * see FF_HWACCEL_CODEC_CAP_*
  3053.      */
  3054.     int capabilities;
  3055.  
  3056.     struct AVHWAccel *next;
  3057.  
  3058.     /**
  3059.      * Called at the beginning of each frame or field picture.
  3060.      *
  3061.      * Meaningful frame information (codec specific) is guaranteed to
  3062.      * be parsed at this point. This function is mandatory.
  3063.      *
  3064.      * Note that buf can be NULL along with buf_size set to 0.
  3065.      * Otherwise, this means the whole frame is available at this point.
  3066.      *
  3067.      * @param avctx the codec context
  3068.      * @param buf the frame data buffer base
  3069.      * @param buf_size the size of the frame in bytes
  3070.      * @return zero if successful, a negative value otherwise
  3071.      */
  3072.     int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
  3073.  
  3074.     /**
  3075.      * Callback for each slice.
  3076.      *
  3077.      * Meaningful slice information (codec specific) is guaranteed to
  3078.      * be parsed at this point. This function is mandatory.
  3079.      *
  3080.      * @param avctx the codec context
  3081.      * @param buf the slice data buffer base
  3082.      * @param buf_size the size of the slice in bytes
  3083.      * @return zero if successful, a negative value otherwise
  3084.      */
  3085.     int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
  3086.  
  3087.     /**
  3088.      * Called at the end of each frame or field picture.
  3089.      *
  3090.      * The whole picture is parsed at this point and can now be sent
  3091.      * to the hardware accelerator. This function is mandatory.
  3092.      *
  3093.      * @param avctx the codec context
  3094.      * @return zero if successful, a negative value otherwise
  3095.      */
  3096.     int (*end_frame)(AVCodecContext *avctx);
  3097.  
  3098.     /**
  3099.      * Size of HW accelerator private data.
  3100.      *
  3101.      * Private data is allocated with av_mallocz() before
  3102.      * AVCodecContext.get_buffer() and deallocated after
  3103.      * AVCodecContext.release_buffer().
  3104.      */
  3105.     int priv_data_size;
  3106. } AVHWAccel;
  3107.  
  3108. /**
  3109.  * @defgroup lavc_picture AVPicture
  3110.  *
  3111.  * Functions for working with AVPicture
  3112.  * @{
  3113.  */
  3114.  
  3115. /**
  3116.  * Picture data structure.
  3117.  *
  3118.  * Up to four components can be stored into it, the last component is
  3119.  * alpha.
  3120.  */
  3121. typedef struct AVPicture {
  3122.     uint8_t *data[AV_NUM_DATA_POINTERS];    ///< pointers to the image data planes
  3123.     int linesize[AV_NUM_DATA_POINTERS];     ///< number of bytes per line
  3124. } AVPicture;
  3125.  
  3126. /**
  3127.  * @}
  3128.  */
  3129.  
  3130. enum AVSubtitleType {
  3131.     SUBTITLE_NONE,
  3132.  
  3133.     SUBTITLE_BITMAP,                ///< A bitmap, pict will be set
  3134.  
  3135.     /**
  3136.      * Plain text, the text field must be set by the decoder and is
  3137.      * authoritative. ass and pict fields may contain approximations.
  3138.      */
  3139.     SUBTITLE_TEXT,
  3140.  
  3141.     /**
  3142.      * Formatted text, the ass field must be set by the decoder and is
  3143.      * authoritative. pict and text fields may contain approximations.
  3144.      */
  3145.     SUBTITLE_ASS,
  3146. };
  3147.  
  3148. #define AV_SUBTITLE_FLAG_FORCED 0x00000001
  3149.  
  3150. typedef struct AVSubtitleRect {
  3151.     int x;         ///< top left corner  of pict, undefined when pict is not set
  3152.     int y;         ///< top left corner  of pict, undefined when pict is not set
  3153.     int w;         ///< width            of pict, undefined when pict is not set
  3154.     int h;         ///< height           of pict, undefined when pict is not set
  3155.     int nb_colors; ///< number of colors in pict, undefined when pict is not set
  3156.  
  3157.     /**
  3158.      * data+linesize for the bitmap of this subtitle.
  3159.      * can be set for text/ass as well once they where rendered
  3160.      */
  3161.     AVPicture pict;
  3162.     enum AVSubtitleType type;
  3163.  
  3164.     char *text;                     ///< 0 terminated plain UTF-8 text
  3165.  
  3166.     /**
  3167.      * 0 terminated ASS/SSA compatible event line.
  3168.      * The presentation of this is unaffected by the other values in this
  3169.      * struct.
  3170.      */
  3171.     char *ass;
  3172.  
  3173.     int flags;
  3174. } AVSubtitleRect;
  3175.  
  3176. typedef struct AVSubtitle {
  3177.     uint16_t format; /* 0 = graphics */
  3178.     uint32_t start_display_time; /* relative to packet pts, in ms */
  3179.     uint32_t end_display_time; /* relative to packet pts, in ms */
  3180.     unsigned num_rects;
  3181.     AVSubtitleRect **rects;
  3182.     int64_t pts;    ///< Same as packet pts, in AV_TIME_BASE
  3183. } AVSubtitle;
  3184.  
  3185. /**
  3186.  * If c is NULL, returns the first registered codec,
  3187.  * if c is non-NULL, returns the next registered codec after c,
  3188.  * or NULL if c is the last one.
  3189.  */
  3190. AVCodec *av_codec_next(const AVCodec *c);
  3191.  
  3192. /**
  3193.  * Return the LIBAVCODEC_VERSION_INT constant.
  3194.  */
  3195. unsigned avcodec_version(void);
  3196.  
  3197. /**
  3198.  * Return the libavcodec build-time configuration.
  3199.  */
  3200. const char *avcodec_configuration(void);
  3201.  
  3202. /**
  3203.  * Return the libavcodec license.
  3204.  */
  3205. const char *avcodec_license(void);
  3206.  
  3207. /**
  3208.  * Register the codec codec and initialize libavcodec.
  3209.  *
  3210.  * @warning either this function or avcodec_register_all() must be called
  3211.  * before any other libavcodec functions.
  3212.  *
  3213.  * @see avcodec_register_all()
  3214.  */
  3215. void avcodec_register(AVCodec *codec);
  3216.  
  3217. /**
  3218.  * Register all the codecs, parsers and bitstream filters which were enabled at
  3219.  * configuration time. If you do not call this function you can select exactly
  3220.  * which formats you want to support, by using the individual registration
  3221.  * functions.
  3222.  *
  3223.  * @see avcodec_register
  3224.  * @see av_register_codec_parser
  3225.  * @see av_register_bitstream_filter
  3226.  */
  3227. void avcodec_register_all(void);
  3228.  
  3229.  
  3230. #if FF_API_ALLOC_CONTEXT
  3231. /**
  3232.  * Allocate an AVCodecContext and set its fields to default values.  The
  3233.  * resulting struct can be deallocated by simply calling av_free().
  3234.  *
  3235.  * @return An AVCodecContext filled with default values or NULL on failure.
  3236.  * @see avcodec_get_context_defaults
  3237.  *
  3238.  * @deprecated use avcodec_alloc_context3()
  3239.  */
  3240. attribute_deprecated
  3241. AVCodecContext *avcodec_alloc_context(void);
  3242.  
  3243. /** THIS FUNCTION IS NOT YET PART OF THE PUBLIC API!
  3244.  *  we WILL change its arguments and name a few times! */
  3245. attribute_deprecated
  3246. AVCodecContext *avcodec_alloc_context2(enum AVMediaType);
  3247.  
  3248. /**
  3249.  * Set the fields of the given AVCodecContext to default values.
  3250.  *
  3251.  * @param s The AVCodecContext of which the fields should be set to default values.
  3252.  * @deprecated use avcodec_get_context_defaults3
  3253.  */
  3254. attribute_deprecated
  3255. void avcodec_get_context_defaults(AVCodecContext *s);
  3256.  
  3257. /** THIS FUNCTION IS NOT YET PART OF THE PUBLIC API!
  3258.  *  we WILL change its arguments and name a few times! */
  3259. attribute_deprecated
  3260. void avcodec_get_context_defaults2(AVCodecContext *s, enum AVMediaType);
  3261. #endif
  3262.  
  3263. /**
  3264.  * Allocate an AVCodecContext and set its fields to default values.  The
  3265.  * resulting struct can be deallocated by calling avcodec_close() on it followed
  3266.  * by av_free().
  3267.  *
  3268.  * @param codec if non-NULL, allocate private data and initialize defaults
  3269.  *              for the given codec. It is illegal to then call avcodec_open2()
  3270.  *              with a different codec.
  3271.  *              If NULL, then the codec-specific defaults won't be initialized,
  3272.  *              which may result in suboptimal default settings (this is
  3273.  *              important mainly for encoders, e.g. libx264).
  3274.  *
  3275.  * @return An AVCodecContext filled with default values or NULL on failure.
  3276.  * @see avcodec_get_context_defaults
  3277.  */
  3278. AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
  3279.  
  3280. /**
  3281.  * Set the fields of the given AVCodecContext to default values corresponding
  3282.  * to the given codec (defaults may be codec-dependent).
  3283.  *
  3284.  * Do not call this function if a non-NULL codec has been passed
  3285.  * to avcodec_alloc_context3() that allocated this AVCodecContext.
  3286.  * If codec is non-NULL, it is illegal to call avcodec_open2() with a
  3287.  * different codec on this AVCodecContext.
  3288.  */
  3289. int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
  3290.  
  3291. /**
  3292.  * Get the AVClass for AVCodecContext. It can be used in combination with
  3293.  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
  3294.  *
  3295.  * @see av_opt_find().
  3296.  */
  3297. const AVClass *avcodec_get_class(void);
  3298.  
  3299. /**
  3300.  * Get the AVClass for AVFrame. It can be used in combination with
  3301.  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
  3302.  *
  3303.  * @see av_opt_find().
  3304.  */
  3305. const AVClass *avcodec_get_frame_class(void);
  3306.  
  3307. /**
  3308.  * Get the AVClass for AVSubtitleRect. It can be used in combination with
  3309.  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
  3310.  *
  3311.  * @see av_opt_find().
  3312.  */
  3313. const AVClass *avcodec_get_subtitle_rect_class(void);
  3314.  
  3315. /**
  3316.  * Copy the settings of the source AVCodecContext into the destination
  3317.  * AVCodecContext. The resulting destination codec context will be
  3318.  * unopened, i.e. you are required to call avcodec_open2() before you
  3319.  * can use this AVCodecContext to decode/encode video/audio data.
  3320.  *
  3321.  * @param dest target codec context, should be initialized with
  3322.  *             avcodec_alloc_context3(NULL), but otherwise uninitialized
  3323.  * @param src source codec context
  3324.  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
  3325.  */
  3326. int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
  3327.  
  3328. /**
  3329.  * Allocate an AVFrame and set its fields to default values.  The resulting
  3330.  * struct must be freed using avcodec_free_frame().
  3331.  *
  3332.  * @return An AVFrame filled with default values or NULL on failure.
  3333.  * @see avcodec_get_frame_defaults
  3334.  */
  3335. AVFrame *avcodec_alloc_frame(void);
  3336.  
  3337. /**
  3338.  * Set the fields of the given AVFrame to default values.
  3339.  *
  3340.  * @param frame The AVFrame of which the fields should be set to default values.
  3341.  */
  3342. void avcodec_get_frame_defaults(AVFrame *frame);
  3343.  
  3344. /**
  3345.  * Free the frame and any dynamically allocated objects in it,
  3346.  * e.g. extended_data.
  3347.  *
  3348.  * @param frame frame to be freed. The pointer will be set to NULL.
  3349.  *
  3350.  * @warning this function does NOT free the data buffers themselves
  3351.  * (it does not know how, since they might have been allocated with
  3352.  *  a custom get_buffer()).
  3353.  */
  3354. void avcodec_free_frame(AVFrame **frame);
  3355.  
  3356. #if FF_API_AVCODEC_OPEN
  3357. /**
  3358.  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
  3359.  * function the context has to be allocated.
  3360.  *
  3361.  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
  3362.  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
  3363.  * retrieving a codec.
  3364.  *
  3365.  * @warning This function is not thread safe!
  3366.  *
  3367.  * @code
  3368.  * avcodec_register_all();
  3369.  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
  3370.  * if (!codec)
  3371.  *     exit(1);
  3372.  *
  3373.  * context = avcodec_alloc_context3(codec);
  3374.  *
  3375.  * if (avcodec_open(context, codec) < 0)
  3376.  *     exit(1);
  3377.  * @endcode
  3378.  *
  3379.  * @param avctx The context which will be set up to use the given codec.
  3380.  * @param codec The codec to use within the context.
  3381.  * @return zero on success, a negative value on error
  3382.  * @see avcodec_alloc_context3, avcodec_find_decoder, avcodec_find_encoder, avcodec_close
  3383.  *
  3384.  * @deprecated use avcodec_open2
  3385.  */
  3386. attribute_deprecated
  3387. int avcodec_open(AVCodecContext *avctx, AVCodec *codec);
  3388. #endif
  3389.  
  3390. /**
  3391.  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
  3392.  * function the context has to be allocated with avcodec_alloc_context3().
  3393.  *
  3394.  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
  3395.  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
  3396.  * retrieving a codec.
  3397.  *
  3398.  * @warning This function is not thread safe!
  3399.  *
  3400.  * @code
  3401.  * avcodec_register_all();
  3402.  * av_dict_set(&opts, "b", "2.5M", 0);
  3403.  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
  3404.  * if (!codec)
  3405.  *     exit(1);
  3406.  *
  3407.  * context = avcodec_alloc_context3(codec);
  3408.  *
  3409.  * if (avcodec_open2(context, codec, opts) < 0)
  3410.  *     exit(1);
  3411.  * @endcode
  3412.  *
  3413.  * @param avctx The context to initialize.
  3414.  * @param codec The codec to open this context for. If a non-NULL codec has been
  3415.  *              previously passed to avcodec_alloc_context3() or
  3416.  *              avcodec_get_context_defaults3() for this context, then this
  3417.  *              parameter MUST be either NULL or equal to the previously passed
  3418.  *              codec.
  3419.  * @param options A dictionary filled with AVCodecContext and codec-private options.
  3420.  *                On return this object will be filled with options that were not found.
  3421.  *
  3422.  * @return zero on success, a negative value on error
  3423.  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
  3424.  *      av_dict_set(), av_opt_find().
  3425.  */
  3426. int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
  3427.  
  3428. /**
  3429.  * Close a given AVCodecContext and free all the data associated with it
  3430.  * (but not the AVCodecContext itself).
  3431.  *
  3432.  * Calling this function on an AVCodecContext that hasn't been opened will free
  3433.  * the codec-specific data allocated in avcodec_alloc_context3() /
  3434.  * avcodec_get_context_defaults3() with a non-NULL codec. Subsequent calls will
  3435.  * do nothing.
  3436.  */
  3437. int avcodec_close(AVCodecContext *avctx);
  3438.  
  3439. /**
  3440.  * Free all allocated data in the given subtitle struct.
  3441.  *
  3442.  * @param sub AVSubtitle to free.
  3443.  */
  3444. void avsubtitle_free(AVSubtitle *sub);
  3445.  
  3446. /**
  3447.  * @}
  3448.  */
  3449.  
  3450. /**
  3451.  * @addtogroup lavc_packet
  3452.  * @{
  3453.  */
  3454.  
  3455. #if FF_API_DESTRUCT_PACKET
  3456. /**
  3457.  * Default packet destructor.
  3458.  * @deprecated use the AVBuffer API instead
  3459.  */
  3460. attribute_deprecated
  3461. void av_destruct_packet(AVPacket *pkt);
  3462. #endif
  3463.  
  3464. /**
  3465.  * Initialize optional fields of a packet with default values.
  3466.  *
  3467.  * Note, this does not touch the data and size members, which have to be
  3468.  * initialized separately.
  3469.  *
  3470.  * @param pkt packet
  3471.  */
  3472. void av_init_packet(AVPacket *pkt);
  3473.  
  3474. /**
  3475.  * Allocate the payload of a packet and initialize its fields with
  3476.  * default values.
  3477.  *
  3478.  * @param pkt packet
  3479.  * @param size wanted payload size
  3480.  * @return 0 if OK, AVERROR_xxx otherwise
  3481.  */
  3482. int av_new_packet(AVPacket *pkt, int size);
  3483.  
  3484. /**
  3485.  * Reduce packet size, correctly zeroing padding
  3486.  *
  3487.  * @param pkt packet
  3488.  * @param size new size
  3489.  */
  3490. void av_shrink_packet(AVPacket *pkt, int size);
  3491.  
  3492. /**
  3493.  * Increase packet size, correctly zeroing padding
  3494.  *
  3495.  * @param pkt packet
  3496.  * @param grow_by number of bytes by which to increase the size of the packet
  3497.  */
  3498. int av_grow_packet(AVPacket *pkt, int grow_by);
  3499.  
  3500. /**
  3501.  * Initialize a reference-counted packet from av_malloc()ed data.
  3502.  *
  3503.  * @param pkt packet to be initialized. This function will set the data, size,
  3504.  *        buf and destruct fields, all others are left untouched.
  3505.  * @param data Data allocated by av_malloc() to be used as packet data. If this
  3506.  *        function returns successfully, the data is owned by the underlying AVBuffer.
  3507.  *        The caller may not access the data through other means.
  3508.  * @param size size of data in bytes, without the padding. I.e. the full buffer
  3509.  *        size is assumed to be size + FF_INPUT_BUFFER_PADDING_SIZE.
  3510.  *
  3511.  * @return 0 on success, a negative AVERROR on error
  3512.  */
  3513. int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
  3514.  
  3515. /**
  3516.  * @warning This is a hack - the packet memory allocation stuff is broken. The
  3517.  * packet is allocated if it was not really allocated.
  3518.  */
  3519. int av_dup_packet(AVPacket *pkt);
  3520.  
  3521. /**
  3522.  * Copy packet, including contents
  3523.  *
  3524.  * @return 0 on success, negative AVERROR on fail
  3525.  */
  3526. int av_copy_packet(AVPacket *dst, AVPacket *src);
  3527.  
  3528. /**
  3529.  * Copy packet side data
  3530.  *
  3531.  * @return 0 on success, negative AVERROR on fail
  3532.  */
  3533. int av_copy_packet_side_data(AVPacket *dst, AVPacket *src);
  3534.  
  3535. /**
  3536.  * Free a packet.
  3537.  *
  3538.  * @param pkt packet to free
  3539.  */
  3540. void av_free_packet(AVPacket *pkt);
  3541.  
  3542. /**
  3543.  * Allocate new information of a packet.
  3544.  *
  3545.  * @param pkt packet
  3546.  * @param type side information type
  3547.  * @param size side information size
  3548.  * @return pointer to fresh allocated data or NULL otherwise
  3549.  */
  3550. uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
  3551.                                  int size);
  3552.  
  3553. /**
  3554.  * Shrink the already allocated side data buffer
  3555.  *
  3556.  * @param pkt packet
  3557.  * @param type side information type
  3558.  * @param size new side information size
  3559.  * @return 0 on success, < 0 on failure
  3560.  */
  3561. int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
  3562.                                int size);
  3563.  
  3564. /**
  3565.  * Get side information from packet.
  3566.  *
  3567.  * @param pkt packet
  3568.  * @param type desired side information type
  3569.  * @param size pointer for side information size to store (optional)
  3570.  * @return pointer to data if present or NULL otherwise
  3571.  */
  3572. uint8_t* av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
  3573.                                  int *size);
  3574.  
  3575. int av_packet_merge_side_data(AVPacket *pkt);
  3576.  
  3577. int av_packet_split_side_data(AVPacket *pkt);
  3578.  
  3579.  
  3580. /**
  3581.  * Convenience function to free all the side data stored.
  3582.  * All the other fields stay untouched.
  3583.  *
  3584.  * @param pkt packet
  3585.  */
  3586. void av_packet_free_side_data(AVPacket *pkt);
  3587.  
  3588. /**
  3589.  * Setup a new reference to the data described by a given packet
  3590.  *
  3591.  * If src is reference-counted, setup dst as a new reference to the
  3592.  * buffer in src. Otherwise allocate a new buffer in dst and copy the
  3593.  * data from src into it.
  3594.  *
  3595.  * All the other fields are copied from src.
  3596.  *
  3597.  * @see av_packet_unref
  3598.  *
  3599.  * @param dst Destination packet
  3600.  * @param src Source packet
  3601.  *
  3602.  * @return 0 on success, a negative AVERROR on error.
  3603.  */
  3604. int av_packet_ref(AVPacket *dst, AVPacket *src);
  3605.  
  3606. /**
  3607.  * Wipe the packet.
  3608.  *
  3609.  * Unreference the buffer referenced by the packet and reset the
  3610.  * remaining packet fields to their default values.
  3611.  *
  3612.  * @param pkt The packet to be unreferenced.
  3613.  */
  3614. void av_packet_unref(AVPacket *pkt);
  3615.  
  3616. /**
  3617.  * Move every field in src to dst and reset src.
  3618.  *
  3619.  * @see av_packet_unref
  3620.  *
  3621.  * @param src Source packet, will be reset
  3622.  * @param dst Destination packet
  3623.  */
  3624. void av_packet_move_ref(AVPacket *dst, AVPacket *src);
  3625.  
  3626. /**
  3627.  * Copy only "properties" fields from src to dst.
  3628.  *
  3629.  * Properties for the purpose of this function are all the fields
  3630.  * beside those related to the packet data (buf, data, size)
  3631.  *
  3632.  * @param dst Destination packet
  3633.  * @param src Source packet
  3634.  *
  3635.  * @return 0 on success AVERROR on failure.
  3636.  *
  3637.  */
  3638. int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
  3639.  
  3640. /**
  3641.  * @}
  3642.  */
  3643.  
  3644. /**
  3645.  * @addtogroup lavc_decoding
  3646.  * @{
  3647.  */
  3648.  
  3649. /**
  3650.  * Find a registered decoder with a matching codec ID.
  3651.  *
  3652.  * @param id AVCodecID of the requested decoder
  3653.  * @return A decoder if one was found, NULL otherwise.
  3654.  */
  3655. AVCodec *avcodec_find_decoder(enum AVCodecID id);
  3656.  
  3657. /**
  3658.  * Find a registered decoder with the specified name.
  3659.  *
  3660.  * @param name name of the requested decoder
  3661.  * @return A decoder if one was found, NULL otherwise.
  3662.  */
  3663. AVCodec *avcodec_find_decoder_by_name(const char *name);
  3664.  
  3665. #if FF_API_GET_BUFFER
  3666. attribute_deprecated int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic);
  3667. attribute_deprecated void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic);
  3668. attribute_deprecated int avcodec_default_reget_buffer(AVCodecContext *s, AVFrame *pic);
  3669. #endif
  3670.  
  3671. /**
  3672.  * The default callback for AVCodecContext.get_buffer2(). It is made public so
  3673.  * it can be called by custom get_buffer2() implementations for decoders without
  3674.  * CODEC_CAP_DR1 set.
  3675.  */
  3676. int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
  3677.  
  3678. /**
  3679.  * Return the amount of padding in pixels which the get_buffer callback must
  3680.  * provide around the edge of the image for codecs which do not have the
  3681.  * CODEC_FLAG_EMU_EDGE flag.
  3682.  *
  3683.  * @return Required padding in pixels.
  3684.  */
  3685. unsigned avcodec_get_edge_width(void);
  3686.  
  3687. /**
  3688.  * Modify width and height values so that they will result in a memory
  3689.  * buffer that is acceptable for the codec if you do not use any horizontal
  3690.  * padding.
  3691.  *
  3692.  * May only be used if a codec with CODEC_CAP_DR1 has been opened.
  3693.  * If CODEC_FLAG_EMU_EDGE is not set, the dimensions must have been increased
  3694.  * according to avcodec_get_edge_width() before.
  3695.  */
  3696. void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
  3697.  
  3698. /**
  3699.  * Modify width and height values so that they will result in a memory
  3700.  * buffer that is acceptable for the codec if you also ensure that all
  3701.  * line sizes are a multiple of the respective linesize_align[i].
  3702.  *
  3703.  * May only be used if a codec with CODEC_CAP_DR1 has been opened.
  3704.  * If CODEC_FLAG_EMU_EDGE is not set, the dimensions must have been increased
  3705.  * according to avcodec_get_edge_width() before.
  3706.  */
  3707. void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
  3708.                                int linesize_align[AV_NUM_DATA_POINTERS]);
  3709.  
  3710. /**
  3711.  * Converts AVChromaLocation to swscale x/y chroma position.
  3712.  *
  3713.  * The positions represent the chroma (0,0) position in a coordinates system
  3714.  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
  3715.  *
  3716.  * @param xpos  horizontal chroma sample position
  3717.  * @param ypos  vertical   chroma sample position
  3718.  */
  3719. int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
  3720.  
  3721. /**
  3722.  * Converts swscale x/y chroma position to AVChromaLocation.
  3723.  *
  3724.  * The positions represent the chroma (0,0) position in a coordinates system
  3725.  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
  3726.  *
  3727.  * @param xpos  horizontal chroma sample position
  3728.  * @param ypos  vertical   chroma sample position
  3729.  */
  3730. enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
  3731.  
  3732. #if FF_API_OLD_DECODE_AUDIO
  3733. /**
  3734.  * Wrapper function which calls avcodec_decode_audio4.
  3735.  *
  3736.  * @deprecated Use avcodec_decode_audio4 instead.
  3737.  *
  3738.  * Decode the audio frame of size avpkt->size from avpkt->data into samples.
  3739.  * Some decoders may support multiple frames in a single AVPacket, such
  3740.  * decoders would then just decode the first frame. In this case,
  3741.  * avcodec_decode_audio3 has to be called again with an AVPacket that contains
  3742.  * the remaining data in order to decode the second frame etc.
  3743.  * If no frame
  3744.  * could be outputted, frame_size_ptr is zero. Otherwise, it is the
  3745.  * decompressed frame size in bytes.
  3746.  *
  3747.  * @warning You must set frame_size_ptr to the allocated size of the
  3748.  * output buffer before calling avcodec_decode_audio3().
  3749.  *
  3750.  * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
  3751.  * the actual read bytes because some optimized bitstream readers read 32 or 64
  3752.  * bits at once and could read over the end.
  3753.  *
  3754.  * @warning The end of the input buffer avpkt->data should be set to 0 to ensure that
  3755.  * no overreading happens for damaged MPEG streams.
  3756.  *
  3757.  * @warning You must not provide a custom get_buffer() when using
  3758.  * avcodec_decode_audio3().  Doing so will override it with
  3759.  * avcodec_default_get_buffer.  Use avcodec_decode_audio4() instead,
  3760.  * which does allow the application to provide a custom get_buffer().
  3761.  *
  3762.  * @note You might have to align the input buffer avpkt->data and output buffer
  3763.  * samples. The alignment requirements depend on the CPU: On some CPUs it isn't
  3764.  * necessary at all, on others it won't work at all if not aligned and on others
  3765.  * it will work but it will have an impact on performance.
  3766.  *
  3767.  * In practice, avpkt->data should have 4 byte alignment at minimum and
  3768.  * samples should be 16 byte aligned unless the CPU doesn't need it
  3769.  * (AltiVec and SSE do).
  3770.  *
  3771.  * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
  3772.  * between input and output, these need to be fed with avpkt->data=NULL,
  3773.  * avpkt->size=0 at the end to return the remaining frames.
  3774.  *
  3775.  * @param avctx the codec context
  3776.  * @param[out] samples the output buffer, sample type in avctx->sample_fmt
  3777.  *                     If the sample format is planar, each channel plane will
  3778.  *                     be the same size, with no padding between channels.
  3779.  * @param[in,out] frame_size_ptr the output buffer size in bytes
  3780.  * @param[in] avpkt The input AVPacket containing the input buffer.
  3781.  *            You can create such packet with av_init_packet() and by then setting
  3782.  *            data and size, some decoders might in addition need other fields.
  3783.  *            All decoders are designed to use the least fields possible though.
  3784.  * @return On error a negative value is returned, otherwise the number of bytes
  3785.  * used or zero if no frame data was decompressed (used) from the input AVPacket.
  3786.  */
  3787. attribute_deprecated int avcodec_decode_audio3(AVCodecContext *avctx, int16_t *samples,
  3788.                          int *frame_size_ptr,
  3789.                          AVPacket *avpkt);
  3790. #endif
  3791.  
  3792. /**
  3793.  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
  3794.  *
  3795.  * Some decoders may support multiple frames in a single AVPacket. Such
  3796.  * decoders would then just decode the first frame and the return value would be
  3797.  * less than the packet size. In this case, avcodec_decode_audio4 has to be
  3798.  * called again with an AVPacket containing the remaining data in order to
  3799.  * decode the second frame, etc...  Even if no frames are returned, the packet
  3800.  * needs to be fed to the decoder with remaining data until it is completely
  3801.  * consumed or an error occurs.
  3802.  *
  3803.  * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
  3804.  * and output. This means that for some packets they will not immediately
  3805.  * produce decoded output and need to be flushed at the end of decoding to get
  3806.  * all the decoded data. Flushing is done by calling this function with packets
  3807.  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
  3808.  * returning samples. It is safe to flush even those decoders that are not
  3809.  * marked with CODEC_CAP_DELAY, then no samples will be returned.
  3810.  *
  3811.  * @warning The input buffer, avpkt->data must be FF_INPUT_BUFFER_PADDING_SIZE
  3812.  *          larger than the actual read bytes because some optimized bitstream
  3813.  *          readers read 32 or 64 bits at once and could read over the end.
  3814.  *
  3815.  * @param      avctx the codec context
  3816.  * @param[out] frame The AVFrame in which to store decoded audio samples.
  3817.  *                   The decoder will allocate a buffer for the decoded frame by
  3818.  *                   calling the AVCodecContext.get_buffer2() callback.
  3819.  *                   When AVCodecContext.refcounted_frames is set to 1, the frame is
  3820.  *                   reference counted and the returned reference belongs to the
  3821.  *                   caller. The caller must release the frame using av_frame_unref()
  3822.  *                   when the frame is no longer needed. The caller may safely write
  3823.  *                   to the frame if av_frame_is_writable() returns 1.
  3824.  *                   When AVCodecContext.refcounted_frames is set to 0, the returned
  3825.  *                   reference belongs to the decoder and is valid only until the
  3826.  *                   next call to this function or until closing or flushing the
  3827.  *                   decoder. The caller may not write to it.
  3828.  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
  3829.  *                           non-zero. Note that this field being set to zero
  3830.  *                           does not mean that an error has occurred. For
  3831.  *                           decoders with CODEC_CAP_DELAY set, no given decode
  3832.  *                           call is guaranteed to produce a frame.
  3833.  * @param[in]  avpkt The input AVPacket containing the input buffer.
  3834.  *                   At least avpkt->data and avpkt->size should be set. Some
  3835.  *                   decoders might also require additional fields to be set.
  3836.  * @return A negative error code is returned if an error occurred during
  3837.  *         decoding, otherwise the number of bytes consumed from the input
  3838.  *         AVPacket is returned.
  3839.  */
  3840. int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
  3841.                           int *got_frame_ptr, const AVPacket *avpkt);
  3842.  
  3843. /**
  3844.  * Decode the video frame of size avpkt->size from avpkt->data into picture.
  3845.  * Some decoders may support multiple frames in a single AVPacket, such
  3846.  * decoders would then just decode the first frame.
  3847.  *
  3848.  * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
  3849.  * the actual read bytes because some optimized bitstream readers read 32 or 64
  3850.  * bits at once and could read over the end.
  3851.  *
  3852.  * @warning The end of the input buffer buf should be set to 0 to ensure that
  3853.  * no overreading happens for damaged MPEG streams.
  3854.  *
  3855.  * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
  3856.  * between input and output, these need to be fed with avpkt->data=NULL,
  3857.  * avpkt->size=0 at the end to return the remaining frames.
  3858.  *
  3859.  * @param avctx the codec context
  3860.  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
  3861.  *             Use av_frame_alloc() to get an AVFrame. The codec will
  3862.  *             allocate memory for the actual bitmap by calling the
  3863.  *             AVCodecContext.get_buffer2() callback.
  3864.  *             When AVCodecContext.refcounted_frames is set to 1, the frame is
  3865.  *             reference counted and the returned reference belongs to the
  3866.  *             caller. The caller must release the frame using av_frame_unref()
  3867.  *             when the frame is no longer needed. The caller may safely write
  3868.  *             to the frame if av_frame_is_writable() returns 1.
  3869.  *             When AVCodecContext.refcounted_frames is set to 0, the returned
  3870.  *             reference belongs to the decoder and is valid only until the
  3871.  *             next call to this function or until closing or flushing the
  3872.  *             decoder. The caller may not write to it.
  3873.  *
  3874.  * @param[in] avpkt The input AVPacket containing the input buffer.
  3875.  *            You can create such packet with av_init_packet() and by then setting
  3876.  *            data and size, some decoders might in addition need other fields like
  3877.  *            flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
  3878.  *            fields possible.
  3879.  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
  3880.  * @return On error a negative value is returned, otherwise the number of bytes
  3881.  * used or zero if no frame could be decompressed.
  3882.  */
  3883. int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
  3884.                          int *got_picture_ptr,
  3885.                          const AVPacket *avpkt);
  3886.  
  3887. /**
  3888.  * Decode a subtitle message.
  3889.  * Return a negative value on error, otherwise return the number of bytes used.
  3890.  * If no subtitle could be decompressed, got_sub_ptr is zero.
  3891.  * Otherwise, the subtitle is stored in *sub.
  3892.  * Note that CODEC_CAP_DR1 is not available for subtitle codecs. This is for
  3893.  * simplicity, because the performance difference is expect to be negligible
  3894.  * and reusing a get_buffer written for video codecs would probably perform badly
  3895.  * due to a potentially very different allocation pattern.
  3896.  *
  3897.  * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
  3898.  * and output. This means that for some packets they will not immediately
  3899.  * produce decoded output and need to be flushed at the end of decoding to get
  3900.  * all the decoded data. Flushing is done by calling this function with packets
  3901.  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
  3902.  * returning subtitles. It is safe to flush even those decoders that are not
  3903.  * marked with CODEC_CAP_DELAY, then no subtitles will be returned.
  3904.  *
  3905.  * @param avctx the codec context
  3906.  * @param[out] sub The AVSubtitle in which the decoded subtitle will be stored, must be
  3907.                    freed with avsubtitle_free if *got_sub_ptr is set.
  3908.  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
  3909.  * @param[in] avpkt The input AVPacket containing the input buffer.
  3910.  */
  3911. int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
  3912.                             int *got_sub_ptr,
  3913.                             AVPacket *avpkt);
  3914.  
  3915. /**
  3916.  * @defgroup lavc_parsing Frame parsing
  3917.  * @{
  3918.  */
  3919.  
  3920. enum AVPictureStructure {
  3921.     AV_PICTURE_STRUCTURE_UNKNOWN,      //< unknown
  3922.     AV_PICTURE_STRUCTURE_TOP_FIELD,    //< coded as top field
  3923.     AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
  3924.     AV_PICTURE_STRUCTURE_FRAME,        //< coded as frame
  3925. };
  3926.  
  3927. typedef struct AVCodecParserContext {
  3928.     void *priv_data;
  3929.     struct AVCodecParser *parser;
  3930.     int64_t frame_offset; /* offset of the current frame */
  3931.     int64_t cur_offset; /* current offset
  3932.                            (incremented by each av_parser_parse()) */
  3933.     int64_t next_frame_offset; /* offset of the next frame */
  3934.     /* video info */
  3935.     int pict_type; /* XXX: Put it back in AVCodecContext. */
  3936.     /**
  3937.      * This field is used for proper frame duration computation in lavf.
  3938.      * It signals, how much longer the frame duration of the current frame
  3939.      * is compared to normal frame duration.
  3940.      *
  3941.      * frame_duration = (1 + repeat_pict) * time_base
  3942.      *
  3943.      * It is used by codecs like H.264 to display telecined material.
  3944.      */
  3945.     int repeat_pict; /* XXX: Put it back in AVCodecContext. */
  3946.     int64_t pts;     /* pts of the current frame */
  3947.     int64_t dts;     /* dts of the current frame */
  3948.  
  3949.     /* private data */
  3950.     int64_t last_pts;
  3951.     int64_t last_dts;
  3952.     int fetch_timestamp;
  3953.  
  3954. #define AV_PARSER_PTS_NB 4
  3955.     int cur_frame_start_index;
  3956.     int64_t cur_frame_offset[AV_PARSER_PTS_NB];
  3957.     int64_t cur_frame_pts[AV_PARSER_PTS_NB];
  3958.     int64_t cur_frame_dts[AV_PARSER_PTS_NB];
  3959.  
  3960.     int flags;
  3961. #define PARSER_FLAG_COMPLETE_FRAMES           0x0001
  3962. #define PARSER_FLAG_ONCE                      0x0002
  3963. /// Set if the parser has a valid file offset
  3964. #define PARSER_FLAG_FETCHED_OFFSET            0x0004
  3965. #define PARSER_FLAG_USE_CODEC_TS              0x1000
  3966.  
  3967.     int64_t offset;      ///< byte offset from starting packet start
  3968.     int64_t cur_frame_end[AV_PARSER_PTS_NB];
  3969.  
  3970.     /**
  3971.      * Set by parser to 1 for key frames and 0 for non-key frames.
  3972.      * It is initialized to -1, so if the parser doesn't set this flag,
  3973.      * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
  3974.      * will be used.
  3975.      */
  3976.     int key_frame;
  3977.  
  3978.     /**
  3979.      * Time difference in stream time base units from the pts of this
  3980.      * packet to the point at which the output from the decoder has converged
  3981.      * independent from the availability of previous frames. That is, the
  3982.      * frames are virtually identical no matter if decoding started from
  3983.      * the very first frame or from this keyframe.
  3984.      * Is AV_NOPTS_VALUE if unknown.
  3985.      * This field is not the display duration of the current frame.
  3986.      * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
  3987.      * set.
  3988.      *
  3989.      * The purpose of this field is to allow seeking in streams that have no
  3990.      * keyframes in the conventional sense. It corresponds to the
  3991.      * recovery point SEI in H.264 and match_time_delta in NUT. It is also
  3992.      * essential for some types of subtitle streams to ensure that all
  3993.      * subtitles are correctly displayed after seeking.
  3994.      */
  3995.     int64_t convergence_duration;
  3996.  
  3997.     // Timestamp generation support:
  3998.     /**
  3999.      * Synchronization point for start of timestamp generation.
  4000.      *
  4001.      * Set to >0 for sync point, 0 for no sync point and <0 for undefined
  4002.      * (default).
  4003.      *
  4004.      * For example, this corresponds to presence of H.264 buffering period
  4005.      * SEI message.
  4006.      */
  4007.     int dts_sync_point;
  4008.  
  4009.     /**
  4010.      * Offset of the current timestamp against last timestamp sync point in
  4011.      * units of AVCodecContext.time_base.
  4012.      *
  4013.      * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
  4014.      * contain a valid timestamp offset.
  4015.      *
  4016.      * Note that the timestamp of sync point has usually a nonzero
  4017.      * dts_ref_dts_delta, which refers to the previous sync point. Offset of
  4018.      * the next frame after timestamp sync point will be usually 1.
  4019.      *
  4020.      * For example, this corresponds to H.264 cpb_removal_delay.
  4021.      */
  4022.     int dts_ref_dts_delta;
  4023.  
  4024.     /**
  4025.      * Presentation delay of current frame in units of AVCodecContext.time_base.
  4026.      *
  4027.      * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
  4028.      * contain valid non-negative timestamp delta (presentation time of a frame
  4029.      * must not lie in the past).
  4030.      *
  4031.      * This delay represents the difference between decoding and presentation
  4032.      * time of the frame.
  4033.      *
  4034.      * For example, this corresponds to H.264 dpb_output_delay.
  4035.      */
  4036.     int pts_dts_delta;
  4037.  
  4038.     /**
  4039.      * Position of the packet in file.
  4040.      *
  4041.      * Analogous to cur_frame_pts/dts
  4042.      */
  4043.     int64_t cur_frame_pos[AV_PARSER_PTS_NB];
  4044.  
  4045.     /**
  4046.      * Byte position of currently parsed frame in stream.
  4047.      */
  4048.     int64_t pos;
  4049.  
  4050.     /**
  4051.      * Previous frame byte position.
  4052.      */
  4053.     int64_t last_pos;
  4054.  
  4055.     /**
  4056.      * Duration of the current frame.
  4057.      * For audio, this is in units of 1 / AVCodecContext.sample_rate.
  4058.      * For all other types, this is in units of AVCodecContext.time_base.
  4059.      */
  4060.     int duration;
  4061.  
  4062.     enum AVFieldOrder field_order;
  4063.  
  4064.     /**
  4065.      * Indicate whether a picture is coded as a frame, top field or bottom field.
  4066.      *
  4067.      * For example, H.264 field_pic_flag equal to 0 corresponds to
  4068.      * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
  4069.      * equal to 1 and bottom_field_flag equal to 0 corresponds to
  4070.      * AV_PICTURE_STRUCTURE_TOP_FIELD.
  4071.      */
  4072.     enum AVPictureStructure picture_structure;
  4073.  
  4074.     /**
  4075.      * Picture number incremented in presentation or output order.
  4076.      * This field may be reinitialized at the first picture of a new sequence.
  4077.      *
  4078.      * For example, this corresponds to H.264 PicOrderCnt.
  4079.      */
  4080.     int output_picture_number;
  4081. } AVCodecParserContext;
  4082.  
  4083. typedef struct AVCodecParser {
  4084.     int codec_ids[5]; /* several codec IDs are permitted */
  4085.     int priv_data_size;
  4086.     int (*parser_init)(AVCodecParserContext *s);
  4087.     int (*parser_parse)(AVCodecParserContext *s,
  4088.                         AVCodecContext *avctx,
  4089.                         const uint8_t **poutbuf, int *poutbuf_size,
  4090.                         const uint8_t *buf, int buf_size);
  4091.     void (*parser_close)(AVCodecParserContext *s);
  4092.     int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
  4093.     struct AVCodecParser *next;
  4094. } AVCodecParser;
  4095.  
  4096. AVCodecParser *av_parser_next(AVCodecParser *c);
  4097.  
  4098. void av_register_codec_parser(AVCodecParser *parser);
  4099. AVCodecParserContext *av_parser_init(int codec_id);
  4100.  
  4101. /**
  4102.  * Parse a packet.
  4103.  *
  4104.  * @param s             parser context.
  4105.  * @param avctx         codec context.
  4106.  * @param poutbuf       set to pointer to parsed buffer or NULL if not yet finished.
  4107.  * @param poutbuf_size  set to size of parsed buffer or zero if not yet finished.
  4108.  * @param buf           input buffer.
  4109.  * @param buf_size      input length, to signal EOF, this should be 0 (so that the last frame can be output).
  4110.  * @param pts           input presentation timestamp.
  4111.  * @param dts           input decoding timestamp.
  4112.  * @param pos           input byte position in stream.
  4113.  * @return the number of bytes of the input bitstream used.
  4114.  *
  4115.  * Example:
  4116.  * @code
  4117.  *   while(in_len){
  4118.  *       len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
  4119.  *                                        in_data, in_len,
  4120.  *                                        pts, dts, pos);
  4121.  *       in_data += len;
  4122.  *       in_len  -= len;
  4123.  *
  4124.  *       if(size)
  4125.  *          decode_frame(data, size);
  4126.  *   }
  4127.  * @endcode
  4128.  */
  4129. int av_parser_parse2(AVCodecParserContext *s,
  4130.                      AVCodecContext *avctx,
  4131.                      uint8_t **poutbuf, int *poutbuf_size,
  4132.                      const uint8_t *buf, int buf_size,
  4133.                      int64_t pts, int64_t dts,
  4134.                      int64_t pos);
  4135.  
  4136. /**
  4137.  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
  4138.  * @deprecated use AVBitStreamFilter
  4139.  */
  4140. int av_parser_change(AVCodecParserContext *s,
  4141.                      AVCodecContext *avctx,
  4142.                      uint8_t **poutbuf, int *poutbuf_size,
  4143.                      const uint8_t *buf, int buf_size, int keyframe);
  4144. void av_parser_close(AVCodecParserContext *s);
  4145.  
  4146. /**
  4147.  * @}
  4148.  * @}
  4149.  */
  4150.  
  4151. /**
  4152.  * @addtogroup lavc_encoding
  4153.  * @{
  4154.  */
  4155.  
  4156. /**
  4157.  * Find a registered encoder with a matching codec ID.
  4158.  *
  4159.  * @param id AVCodecID of the requested encoder
  4160.  * @return An encoder if one was found, NULL otherwise.
  4161.  */
  4162. AVCodec *avcodec_find_encoder(enum AVCodecID id);
  4163.  
  4164. /**
  4165.  * Find a registered encoder with the specified name.
  4166.  *
  4167.  * @param name name of the requested encoder
  4168.  * @return An encoder if one was found, NULL otherwise.
  4169.  */
  4170. AVCodec *avcodec_find_encoder_by_name(const char *name);
  4171.  
  4172. #if FF_API_OLD_ENCODE_AUDIO
  4173. /**
  4174.  * Encode an audio frame from samples into buf.
  4175.  *
  4176.  * @deprecated Use avcodec_encode_audio2 instead.
  4177.  *
  4178.  * @note The output buffer should be at least FF_MIN_BUFFER_SIZE bytes large.
  4179.  * However, for codecs with avctx->frame_size equal to 0 (e.g. PCM) the user
  4180.  * will know how much space is needed because it depends on the value passed
  4181.  * in buf_size as described below. In that case a lower value can be used.
  4182.  *
  4183.  * @param avctx the codec context
  4184.  * @param[out] buf the output buffer
  4185.  * @param[in] buf_size the output buffer size
  4186.  * @param[in] samples the input buffer containing the samples
  4187.  * The number of samples read from this buffer is frame_size*channels,
  4188.  * both of which are defined in avctx.
  4189.  * For codecs which have avctx->frame_size equal to 0 (e.g. PCM) the number of
  4190.  * samples read from samples is equal to:
  4191.  * buf_size * 8 / (avctx->channels * av_get_bits_per_sample(avctx->codec_id))
  4192.  * This also implies that av_get_bits_per_sample() must not return 0 for these
  4193.  * codecs.
  4194.  * @return On error a negative value is returned, on success zero or the number
  4195.  * of bytes used to encode the data read from the input buffer.
  4196.  */
  4197. int attribute_deprecated avcodec_encode_audio(AVCodecContext *avctx,
  4198.                                               uint8_t *buf, int buf_size,
  4199.                                               const short *samples);
  4200. #endif
  4201.  
  4202. /**
  4203.  * Encode a frame of audio.
  4204.  *
  4205.  * Takes input samples from frame and writes the next output packet, if
  4206.  * available, to avpkt. The output packet does not necessarily contain data for
  4207.  * the most recent frame, as encoders can delay, split, and combine input frames
  4208.  * internally as needed.
  4209.  *
  4210.  * @param avctx     codec context
  4211.  * @param avpkt     output AVPacket.
  4212.  *                  The user can supply an output buffer by setting
  4213.  *                  avpkt->data and avpkt->size prior to calling the
  4214.  *                  function, but if the size of the user-provided data is not
  4215.  *                  large enough, encoding will fail. If avpkt->data and
  4216.  *                  avpkt->size are set, avpkt->destruct must also be set. All
  4217.  *                  other AVPacket fields will be reset by the encoder using
  4218.  *                  av_init_packet(). If avpkt->data is NULL, the encoder will
  4219.  *                  allocate it. The encoder will set avpkt->size to the size
  4220.  *                  of the output packet.
  4221.  *
  4222.  *                  If this function fails or produces no output, avpkt will be
  4223.  *                  freed using av_free_packet() (i.e. avpkt->destruct will be
  4224.  *                  called to free the user supplied buffer).
  4225.  * @param[in] frame AVFrame containing the raw audio data to be encoded.
  4226.  *                  May be NULL when flushing an encoder that has the
  4227.  *                  CODEC_CAP_DELAY capability set.
  4228.  *                  If CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
  4229.  *                  can have any number of samples.
  4230.  *                  If it is not set, frame->nb_samples must be equal to
  4231.  *                  avctx->frame_size for all frames except the last.
  4232.  *                  The final frame may be smaller than avctx->frame_size.
  4233.  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
  4234.  *                            output packet is non-empty, and to 0 if it is
  4235.  *                            empty. If the function returns an error, the
  4236.  *                            packet can be assumed to be invalid, and the
  4237.  *                            value of got_packet_ptr is undefined and should
  4238.  *                            not be used.
  4239.  * @return          0 on success, negative error code on failure
  4240.  */
  4241. int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
  4242.                           const AVFrame *frame, int *got_packet_ptr);
  4243.  
  4244. #if FF_API_OLD_ENCODE_VIDEO
  4245. /**
  4246.  * @deprecated use avcodec_encode_video2() instead.
  4247.  *
  4248.  * Encode a video frame from pict into buf.
  4249.  * The input picture should be
  4250.  * stored using a specific format, namely avctx.pix_fmt.
  4251.  *
  4252.  * @param avctx the codec context
  4253.  * @param[out] buf the output buffer for the bitstream of encoded frame
  4254.  * @param[in] buf_size the size of the output buffer in bytes
  4255.  * @param[in] pict the input picture to encode
  4256.  * @return On error a negative value is returned, on success zero or the number
  4257.  * of bytes used from the output buffer.
  4258.  */
  4259. attribute_deprecated
  4260. int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size,
  4261.                          const AVFrame *pict);
  4262. #endif
  4263.  
  4264. /**
  4265.  * Encode a frame of video.
  4266.  *
  4267.  * Takes input raw video data from frame and writes the next output packet, if
  4268.  * available, to avpkt. The output packet does not necessarily contain data for
  4269.  * the most recent frame, as encoders can delay and reorder input frames
  4270.  * internally as needed.
  4271.  *
  4272.  * @param avctx     codec context
  4273.  * @param avpkt     output AVPacket.
  4274.  *                  The user can supply an output buffer by setting
  4275.  *                  avpkt->data and avpkt->size prior to calling the
  4276.  *                  function, but if the size of the user-provided data is not
  4277.  *                  large enough, encoding will fail. All other AVPacket fields
  4278.  *                  will be reset by the encoder using av_init_packet(). If
  4279.  *                  avpkt->data is NULL, the encoder will allocate it.
  4280.  *                  The encoder will set avpkt->size to the size of the
  4281.  *                  output packet. The returned data (if any) belongs to the
  4282.  *                  caller, he is responsible for freeing it.
  4283.  *
  4284.  *                  If this function fails or produces no output, avpkt will be
  4285.  *                  freed using av_free_packet() (i.e. avpkt->destruct will be
  4286.  *                  called to free the user supplied buffer).
  4287.  * @param[in] frame AVFrame containing the raw video data to be encoded.
  4288.  *                  May be NULL when flushing an encoder that has the
  4289.  *                  CODEC_CAP_DELAY capability set.
  4290.  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
  4291.  *                            output packet is non-empty, and to 0 if it is
  4292.  *                            empty. If the function returns an error, the
  4293.  *                            packet can be assumed to be invalid, and the
  4294.  *                            value of got_packet_ptr is undefined and should
  4295.  *                            not be used.
  4296.  * @return          0 on success, negative error code on failure
  4297.  */
  4298. int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
  4299.                           const AVFrame *frame, int *got_packet_ptr);
  4300.  
  4301. int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
  4302.                             const AVSubtitle *sub);
  4303.  
  4304.  
  4305. /**
  4306.  * @}
  4307.  */
  4308.  
  4309. #if FF_API_AVCODEC_RESAMPLE
  4310. /**
  4311.  * @defgroup lavc_resample Audio resampling
  4312.  * @ingroup libavc
  4313.  * @deprecated use libswresample instead
  4314.  *
  4315.  * @{
  4316.  */
  4317. struct ReSampleContext;
  4318. struct AVResampleContext;
  4319.  
  4320. typedef struct ReSampleContext ReSampleContext;
  4321.  
  4322. /**
  4323.  *  Initialize audio resampling context.
  4324.  *
  4325.  * @param output_channels  number of output channels
  4326.  * @param input_channels   number of input channels
  4327.  * @param output_rate      output sample rate
  4328.  * @param input_rate       input sample rate
  4329.  * @param sample_fmt_out   requested output sample format
  4330.  * @param sample_fmt_in    input sample format
  4331.  * @param filter_length    length of each FIR filter in the filterbank relative to the cutoff frequency
  4332.  * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
  4333.  * @param linear           if 1 then the used FIR filter will be linearly interpolated
  4334.                            between the 2 closest, if 0 the closest will be used
  4335.  * @param cutoff           cutoff frequency, 1.0 corresponds to half the output sampling rate
  4336.  * @return allocated ReSampleContext, NULL if error occurred
  4337.  */
  4338. attribute_deprecated
  4339. ReSampleContext *av_audio_resample_init(int output_channels, int input_channels,
  4340.                                         int output_rate, int input_rate,
  4341.                                         enum AVSampleFormat sample_fmt_out,
  4342.                                         enum AVSampleFormat sample_fmt_in,
  4343.                                         int filter_length, int log2_phase_count,
  4344.                                         int linear, double cutoff);
  4345.  
  4346. attribute_deprecated
  4347. int audio_resample(ReSampleContext *s, short *output, short *input, int nb_samples);
  4348.  
  4349. /**
  4350.  * Free resample context.
  4351.  *
  4352.  * @param s a non-NULL pointer to a resample context previously
  4353.  *          created with av_audio_resample_init()
  4354.  */
  4355. attribute_deprecated
  4356. void audio_resample_close(ReSampleContext *s);
  4357.  
  4358.  
  4359. /**
  4360.  * Initialize an audio resampler.
  4361.  * Note, if either rate is not an integer then simply scale both rates up so they are.
  4362.  * @param filter_length length of each FIR filter in the filterbank relative to the cutoff freq
  4363.  * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
  4364.  * @param linear If 1 then the used FIR filter will be linearly interpolated
  4365.                  between the 2 closest, if 0 the closest will be used
  4366.  * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
  4367.  */
  4368. attribute_deprecated
  4369. struct AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_length, int log2_phase_count, int linear, double cutoff);
  4370.  
  4371. /**
  4372.  * Resample an array of samples using a previously configured context.
  4373.  * @param src an array of unconsumed samples
  4374.  * @param consumed the number of samples of src which have been consumed are returned here
  4375.  * @param src_size the number of unconsumed samples available
  4376.  * @param dst_size the amount of space in samples available in dst
  4377.  * @param update_ctx If this is 0 then the context will not be modified, that way several channels can be resampled with the same context.
  4378.  * @return the number of samples written in dst or -1 if an error occurred
  4379.  */
  4380. attribute_deprecated
  4381. int av_resample(struct AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx);
  4382.  
  4383.  
  4384. /**
  4385.  * Compensate samplerate/timestamp drift. The compensation is done by changing
  4386.  * the resampler parameters, so no audible clicks or similar distortions occur
  4387.  * @param compensation_distance distance in output samples over which the compensation should be performed
  4388.  * @param sample_delta number of output samples which should be output less
  4389.  *
  4390.  * example: av_resample_compensate(c, 10, 500)
  4391.  * here instead of 510 samples only 500 samples would be output
  4392.  *
  4393.  * note, due to rounding the actual compensation might be slightly different,
  4394.  * especially if the compensation_distance is large and the in_rate used during init is small
  4395.  */
  4396. attribute_deprecated
  4397. void av_resample_compensate(struct AVResampleContext *c, int sample_delta, int compensation_distance);
  4398. attribute_deprecated
  4399. void av_resample_close(struct AVResampleContext *c);
  4400.  
  4401. /**
  4402.  * @}
  4403.  */
  4404. #endif
  4405.  
  4406. /**
  4407.  * @addtogroup lavc_picture
  4408.  * @{
  4409.  */
  4410.  
  4411. /**
  4412.  * Allocate memory for the pixels of a picture and setup the AVPicture
  4413.  * fields for it.
  4414.  *
  4415.  * Call avpicture_free() to free it.
  4416.  *
  4417.  * @param picture            the picture structure to be filled in
  4418.  * @param pix_fmt            the pixel format of the picture
  4419.  * @param width              the width of the picture
  4420.  * @param height             the height of the picture
  4421.  * @return zero if successful, a negative error code otherwise
  4422.  *
  4423.  * @see av_image_alloc(), avpicture_fill()
  4424.  */
  4425. int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
  4426.  
  4427. /**
  4428.  * Free a picture previously allocated by avpicture_alloc().
  4429.  * The data buffer used by the AVPicture is freed, but the AVPicture structure
  4430.  * itself is not.
  4431.  *
  4432.  * @param picture the AVPicture to be freed
  4433.  */
  4434. void avpicture_free(AVPicture *picture);
  4435.  
  4436. /**
  4437.  * Setup the picture fields based on the specified image parameters
  4438.  * and the provided image data buffer.
  4439.  *
  4440.  * The picture fields are filled in by using the image data buffer
  4441.  * pointed to by ptr.
  4442.  *
  4443.  * If ptr is NULL, the function will fill only the picture linesize
  4444.  * array and return the required size for the image buffer.
  4445.  *
  4446.  * To allocate an image buffer and fill the picture data in one call,
  4447.  * use avpicture_alloc().
  4448.  *
  4449.  * @param picture       the picture to be filled in
  4450.  * @param ptr           buffer where the image data is stored, or NULL
  4451.  * @param pix_fmt       the pixel format of the image
  4452.  * @param width         the width of the image in pixels
  4453.  * @param height        the height of the image in pixels
  4454.  * @return the size in bytes required for src, a negative error code
  4455.  * in case of failure
  4456.  *
  4457.  * @see av_image_fill_arrays()
  4458.  */
  4459. int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
  4460.                    enum AVPixelFormat pix_fmt, int width, int height);
  4461.  
  4462. /**
  4463.  * Copy pixel data from an AVPicture into a buffer.
  4464.  *
  4465.  * avpicture_get_size() can be used to compute the required size for
  4466.  * the buffer to fill.
  4467.  *
  4468.  * @param src        source picture with filled data
  4469.  * @param pix_fmt    picture pixel format
  4470.  * @param width      picture width
  4471.  * @param height     picture height
  4472.  * @param dest       destination buffer
  4473.  * @param dest_size  destination buffer size in bytes
  4474.  * @return the number of bytes written to dest, or a negative value
  4475.  * (error code) on error, for example if the destination buffer is not
  4476.  * big enough
  4477.  *
  4478.  * @see av_image_copy_to_buffer()
  4479.  */
  4480. int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
  4481.                      int width, int height,
  4482.                      unsigned char *dest, int dest_size);
  4483.  
  4484. /**
  4485.  * Calculate the size in bytes that a picture of the given width and height
  4486.  * would occupy if stored in the given picture format.
  4487.  *
  4488.  * @param pix_fmt    picture pixel format
  4489.  * @param width      picture width
  4490.  * @param height     picture height
  4491.  * @return the computed picture buffer size or a negative error code
  4492.  * in case of error
  4493.  *
  4494.  * @see av_image_get_buffer_size().
  4495.  */
  4496. int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
  4497.  
  4498. #if FF_API_DEINTERLACE
  4499. /**
  4500.  *  deinterlace - if not supported return -1
  4501.  *
  4502.  * @deprecated - use yadif (in libavfilter) instead
  4503.  */
  4504. attribute_deprecated
  4505. int avpicture_deinterlace(AVPicture *dst, const AVPicture *src,
  4506.                           enum AVPixelFormat pix_fmt, int width, int height);
  4507. #endif
  4508. /**
  4509.  * Copy image src to dst. Wraps av_image_copy().
  4510.  */
  4511. void av_picture_copy(AVPicture *dst, const AVPicture *src,
  4512.                      enum AVPixelFormat pix_fmt, int width, int height);
  4513.  
  4514. /**
  4515.  * Crop image top and left side.
  4516.  */
  4517. int av_picture_crop(AVPicture *dst, const AVPicture *src,
  4518.                     enum AVPixelFormat pix_fmt, int top_band, int left_band);
  4519.  
  4520. /**
  4521.  * Pad image.
  4522.  */
  4523. int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
  4524.             int padtop, int padbottom, int padleft, int padright, int *color);
  4525.  
  4526. /**
  4527.  * @}
  4528.  */
  4529.  
  4530. /**
  4531.  * @defgroup lavc_misc Utility functions
  4532.  * @ingroup libavc
  4533.  *
  4534.  * Miscellaneous utility functions related to both encoding and decoding
  4535.  * (or neither).
  4536.  * @{
  4537.  */
  4538.  
  4539. /**
  4540.  * @defgroup lavc_misc_pixfmt Pixel formats
  4541.  *
  4542.  * Functions for working with pixel formats.
  4543.  * @{
  4544.  */
  4545.  
  4546. /**
  4547.  * Utility function to access log2_chroma_w log2_chroma_h from
  4548.  * the pixel format AVPixFmtDescriptor.
  4549.  *
  4550.  * This function asserts that pix_fmt is valid. See av_pix_fmt_get_chroma_sub_sample
  4551.  * for one that returns a failure code and continues in case of invalid
  4552.  * pix_fmts.
  4553.  *
  4554.  * @param[in]  pix_fmt the pixel format
  4555.  * @param[out] h_shift store log2_chroma_w
  4556.  * @param[out] v_shift store log2_chroma_h
  4557.  *
  4558.  * @see av_pix_fmt_get_chroma_sub_sample
  4559.  */
  4560.  
  4561. void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
  4562.  
  4563. /**
  4564.  * Return a value representing the fourCC code associated to the
  4565.  * pixel format pix_fmt, or 0 if no associated fourCC code can be
  4566.  * found.
  4567.  */
  4568. unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
  4569.  
  4570. #define FF_LOSS_RESOLUTION  0x0001 /**< loss due to resolution change */
  4571. #define FF_LOSS_DEPTH       0x0002 /**< loss due to color depth change */
  4572. #define FF_LOSS_COLORSPACE  0x0004 /**< loss due to color space conversion */
  4573. #define FF_LOSS_ALPHA       0x0008 /**< loss of alpha bits */
  4574. #define FF_LOSS_COLORQUANT  0x0010 /**< loss due to color quantization */
  4575. #define FF_LOSS_CHROMA      0x0020 /**< loss of chroma (e.g. RGB to gray conversion) */
  4576.  
  4577. /**
  4578.  * Compute what kind of losses will occur when converting from one specific
  4579.  * pixel format to another.
  4580.  * When converting from one pixel format to another, information loss may occur.
  4581.  * For example, when converting from RGB24 to GRAY, the color information will
  4582.  * be lost. Similarly, other losses occur when converting from some formats to
  4583.  * other formats. These losses can involve loss of chroma, but also loss of
  4584.  * resolution, loss of color depth, loss due to the color space conversion, loss
  4585.  * of the alpha bits or loss due to color quantization.
  4586.  * avcodec_get_fix_fmt_loss() informs you about the various types of losses
  4587.  * which will occur when converting from one pixel format to another.
  4588.  *
  4589.  * @param[in] dst_pix_fmt destination pixel format
  4590.  * @param[in] src_pix_fmt source pixel format
  4591.  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
  4592.  * @return Combination of flags informing you what kind of losses will occur
  4593.  * (maximum loss for an invalid dst_pix_fmt).
  4594.  */
  4595. int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
  4596.                              int has_alpha);
  4597.  
  4598. /**
  4599.  * Find the best pixel format to convert to given a certain source pixel
  4600.  * format.  When converting from one pixel format to another, information loss
  4601.  * may occur.  For example, when converting from RGB24 to GRAY, the color
  4602.  * information will be lost. Similarly, other losses occur when converting from
  4603.  * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
  4604.  * the given pixel formats should be used to suffer the least amount of loss.
  4605.  * The pixel formats from which it chooses one, are determined by the
  4606.  * pix_fmt_list parameter.
  4607.  *
  4608.  *
  4609.  * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
  4610.  * @param[in] src_pix_fmt source pixel format
  4611.  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
  4612.  * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
  4613.  * @return The best pixel format to convert to or -1 if none was found.
  4614.  */
  4615. enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
  4616.                                             enum AVPixelFormat src_pix_fmt,
  4617.                                             int has_alpha, int *loss_ptr);
  4618.  
  4619. /**
  4620.  * Find the best pixel format to convert to given a certain source pixel
  4621.  * format and a selection of two destination pixel formats. When converting from
  4622.  * one pixel format to another, information loss may occur.  For example, when converting
  4623.  * from RGB24 to GRAY, the color information will be lost. Similarly, other losses occur when
  4624.  * converting from some formats to other formats. avcodec_find_best_pix_fmt_of_2() selects which of
  4625.  * the given pixel formats should be used to suffer the least amount of loss.
  4626.  *
  4627.  * If one of the destination formats is AV_PIX_FMT_NONE the other pixel format (if valid) will be
  4628.  * returned.
  4629.  *
  4630.  * @code
  4631.  * src_pix_fmt = AV_PIX_FMT_YUV420P;
  4632.  * dst_pix_fmt1= AV_PIX_FMT_RGB24;
  4633.  * dst_pix_fmt2= AV_PIX_FMT_GRAY8;
  4634.  * dst_pix_fmt3= AV_PIX_FMT_RGB8;
  4635.  * loss= FF_LOSS_CHROMA; // don't care about chroma loss, so chroma loss will be ignored.
  4636.  * dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt1, dst_pix_fmt2, src_pix_fmt, alpha, &loss);
  4637.  * dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt, dst_pix_fmt3, src_pix_fmt, alpha, &loss);
  4638.  * @endcode
  4639.  *
  4640.  * @param[in] dst_pix_fmt1 One of the two destination pixel formats to choose from
  4641.  * @param[in] dst_pix_fmt2 The other of the two destination pixel formats to choose from
  4642.  * @param[in] src_pix_fmt Source pixel format
  4643.  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
  4644.  * @param[in, out] loss_ptr Combination of loss flags. In: selects which of the losses to ignore, i.e.
  4645.  *                               NULL or value of zero means we care about all losses. Out: the loss
  4646.  *                               that occurs when converting from src to selected dst pixel format.
  4647.  * @return The best pixel format to convert to or -1 if none was found.
  4648.  */
  4649. enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
  4650.                                             enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
  4651.  
  4652. attribute_deprecated
  4653. #if AV_HAVE_INCOMPATIBLE_LIBAV_ABI
  4654. enum AVPixelFormat avcodec_find_best_pix_fmt2(const enum AVPixelFormat *pix_fmt_list,
  4655.                                               enum AVPixelFormat src_pix_fmt,
  4656.                                               int has_alpha, int *loss_ptr);
  4657. #else
  4658. enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
  4659.                                             enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
  4660. #endif
  4661.  
  4662.  
  4663. enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
  4664.  
  4665. /**
  4666.  * @}
  4667.  */
  4668.  
  4669. void avcodec_set_dimensions(AVCodecContext *s, int width, int height);
  4670.  
  4671. /**
  4672.  * Put a string representing the codec tag codec_tag in buf.
  4673.  *
  4674.  * @param buf_size size in bytes of buf
  4675.  * @return the length of the string that would have been generated if
  4676.  * enough space had been available, excluding the trailing null
  4677.  */
  4678. size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
  4679.  
  4680. void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
  4681.  
  4682. /**
  4683.  * Return a name for the specified profile, if available.
  4684.  *
  4685.  * @param codec the codec that is searched for the given profile
  4686.  * @param profile the profile value for which a name is requested
  4687.  * @return A name for the profile if found, NULL otherwise.
  4688.  */
  4689. const char *av_get_profile_name(const AVCodec *codec, int profile);
  4690.  
  4691. int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
  4692. int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
  4693. //FIXME func typedef
  4694.  
  4695. /**
  4696.  * Fill AVFrame audio data and linesize pointers.
  4697.  *
  4698.  * The buffer buf must be a preallocated buffer with a size big enough
  4699.  * to contain the specified samples amount. The filled AVFrame data
  4700.  * pointers will point to this buffer.
  4701.  *
  4702.  * AVFrame extended_data channel pointers are allocated if necessary for
  4703.  * planar audio.
  4704.  *
  4705.  * @param frame       the AVFrame
  4706.  *                    frame->nb_samples must be set prior to calling the
  4707.  *                    function. This function fills in frame->data,
  4708.  *                    frame->extended_data, frame->linesize[0].
  4709.  * @param nb_channels channel count
  4710.  * @param sample_fmt  sample format
  4711.  * @param buf         buffer to use for frame data
  4712.  * @param buf_size    size of buffer
  4713.  * @param align       plane size sample alignment (0 = default)
  4714.  * @return            >=0 on success, negative error code on failure
  4715.  * @todo return the size in bytes required to store the samples in
  4716.  * case of success, at the next libavutil bump
  4717.  */
  4718. int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
  4719.                              enum AVSampleFormat sample_fmt, const uint8_t *buf,
  4720.                              int buf_size, int align);
  4721.  
  4722. /**
  4723.  * Reset the internal decoder state / flush internal buffers. Should be called
  4724.  * e.g. when seeking or when switching to a different stream.
  4725.  *
  4726.  * @note when refcounted frames are not used (i.e. avctx->refcounted_frames is 0),
  4727.  * this invalidates the frames previously returned from the decoder. When
  4728.  * refcounted frames are used, the decoder just releases any references it might
  4729.  * keep internally, but the caller's reference remains valid.
  4730.  */
  4731. void avcodec_flush_buffers(AVCodecContext *avctx);
  4732.  
  4733. /**
  4734.  * Return codec bits per sample.
  4735.  *
  4736.  * @param[in] codec_id the codec
  4737.  * @return Number of bits per sample or zero if unknown for the given codec.
  4738.  */
  4739. int av_get_bits_per_sample(enum AVCodecID codec_id);
  4740.  
  4741. /**
  4742.  * Return the PCM codec associated with a sample format.
  4743.  * @param be  endianness, 0 for little, 1 for big,
  4744.  *            -1 (or anything else) for native
  4745.  * @return  AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
  4746.  */
  4747. enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
  4748.  
  4749. /**
  4750.  * Return codec bits per sample.
  4751.  * Only return non-zero if the bits per sample is exactly correct, not an
  4752.  * approximation.
  4753.  *
  4754.  * @param[in] codec_id the codec
  4755.  * @return Number of bits per sample or zero if unknown for the given codec.
  4756.  */
  4757. int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
  4758.  
  4759. /**
  4760.  * Return audio frame duration.
  4761.  *
  4762.  * @param avctx        codec context
  4763.  * @param frame_bytes  size of the frame, or 0 if unknown
  4764.  * @return             frame duration, in samples, if known. 0 if not able to
  4765.  *                     determine.
  4766.  */
  4767. int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
  4768.  
  4769.  
  4770. typedef struct AVBitStreamFilterContext {
  4771.     void *priv_data;
  4772.     struct AVBitStreamFilter *filter;
  4773.     AVCodecParserContext *parser;
  4774.     struct AVBitStreamFilterContext *next;
  4775. } AVBitStreamFilterContext;
  4776.  
  4777.  
  4778. typedef struct AVBitStreamFilter {
  4779.     const char *name;
  4780.     int priv_data_size;
  4781.     int (*filter)(AVBitStreamFilterContext *bsfc,
  4782.                   AVCodecContext *avctx, const char *args,
  4783.                   uint8_t **poutbuf, int *poutbuf_size,
  4784.                   const uint8_t *buf, int buf_size, int keyframe);
  4785.     void (*close)(AVBitStreamFilterContext *bsfc);
  4786.     struct AVBitStreamFilter *next;
  4787. } AVBitStreamFilter;
  4788.  
  4789. /**
  4790.  * Register a bitstream filter.
  4791.  *
  4792.  * The filter will be accessible to the application code through
  4793.  * av_bitstream_filter_next() or can be directly initialized with
  4794.  * av_bitstream_filter_init().
  4795.  *
  4796.  * @see avcodec_register_all()
  4797.  */
  4798. void av_register_bitstream_filter(AVBitStreamFilter *bsf);
  4799.  
  4800. /**
  4801.  * Create and initialize a bitstream filter context given a bitstream
  4802.  * filter name.
  4803.  *
  4804.  * The returned context must be freed with av_bitstream_filter_close().
  4805.  *
  4806.  * @param name    the name of the bitstream filter
  4807.  * @return a bitstream filter context if a matching filter was found
  4808.  * and successfully initialized, NULL otherwise
  4809.  */
  4810. AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
  4811.  
  4812. /**
  4813.  * Filter bitstream.
  4814.  *
  4815.  * This function filters the buffer buf with size buf_size, and places the
  4816.  * filtered buffer in the buffer pointed to by poutbuf.
  4817.  *
  4818.  * The output buffer must be freed by the caller.
  4819.  *
  4820.  * @param bsfc            bitstream filter context created by av_bitstream_filter_init()
  4821.  * @param avctx           AVCodecContext accessed by the filter, may be NULL.
  4822.  *                        If specified, this must point to the encoder context of the
  4823.  *                        output stream the packet is sent to.
  4824.  * @param args            arguments which specify the filter configuration, may be NULL
  4825.  * @param poutbuf         pointer which is updated to point to the filtered buffer
  4826.  * @param poutbuf_size    pointer which is updated to the filtered buffer size in bytes
  4827.  * @param buf             buffer containing the data to filter
  4828.  * @param buf_size        size in bytes of buf
  4829.  * @param keyframe        set to non-zero if the buffer to filter corresponds to a key-frame packet data
  4830.  * @return >= 0 in case of success, or a negative error code in case of failure
  4831.  *
  4832.  * If the return value is positive, an output buffer is allocated and
  4833.  * is availble in *poutbuf, and is distinct from the input buffer.
  4834.  *
  4835.  * If the return value is 0, the output buffer is not allocated and
  4836.  * should be considered identical to the input buffer, or in case
  4837.  * *poutbuf was set it points to the input buffer (not necessarily to
  4838.  * its starting address).
  4839.  */
  4840. int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
  4841.                                AVCodecContext *avctx, const char *args,
  4842.                                uint8_t **poutbuf, int *poutbuf_size,
  4843.                                const uint8_t *buf, int buf_size, int keyframe);
  4844.  
  4845. /**
  4846.  * Release bitstream filter context.
  4847.  *
  4848.  * @param bsf the bitstream filter context created with
  4849.  * av_bitstream_filter_init(), can be NULL
  4850.  */
  4851. void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
  4852.  
  4853. /**
  4854.  * If f is NULL, return the first registered bitstream filter,
  4855.  * if f is non-NULL, return the next registered bitstream filter
  4856.  * after f, or NULL if f is the last one.
  4857.  *
  4858.  * This function can be used to iterate over all registered bitstream
  4859.  * filters.
  4860.  */
  4861. AVBitStreamFilter *av_bitstream_filter_next(AVBitStreamFilter *f);
  4862.  
  4863. /* memory */
  4864.  
  4865. /**
  4866.  * Reallocate the given block if it is not large enough, otherwise do nothing.
  4867.  *
  4868.  * @see av_realloc
  4869.  */
  4870. void *av_fast_realloc(void *ptr, unsigned int *size, size_t min_size);
  4871.  
  4872. /**
  4873.  * Allocate a buffer, reusing the given one if large enough.
  4874.  *
  4875.  * Contrary to av_fast_realloc the current buffer contents might not be
  4876.  * preserved and on error the old buffer is freed, thus no special
  4877.  * handling to avoid memleaks is necessary.
  4878.  *
  4879.  * @param ptr pointer to pointer to already allocated buffer, overwritten with pointer to new buffer
  4880.  * @param size size of the buffer *ptr points to
  4881.  * @param min_size minimum size of *ptr buffer after returning, *ptr will be NULL and
  4882.  *                 *size 0 if an error occurred.
  4883.  */
  4884. void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size);
  4885.  
  4886. /**
  4887.  * Same behaviour av_fast_malloc but the buffer has additional
  4888.  * FF_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
  4889.  *
  4890.  * In addition the whole buffer will initially and after resizes
  4891.  * be 0-initialized so that no uninitialized data will ever appear.
  4892.  */
  4893. void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
  4894.  
  4895. /**
  4896.  * Same behaviour av_fast_padded_malloc except that buffer will always
  4897.  * be 0-initialized after call.
  4898.  */
  4899. void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
  4900.  
  4901. /**
  4902.  * Encode extradata length to a buffer. Used by xiph codecs.
  4903.  *
  4904.  * @param s buffer to write to; must be at least (v/255+1) bytes long
  4905.  * @param v size of extradata in bytes
  4906.  * @return number of bytes written to the buffer.
  4907.  */
  4908. unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
  4909.  
  4910. #if FF_API_MISSING_SAMPLE
  4911. /**
  4912.  * Log a generic warning message about a missing feature. This function is
  4913.  * intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
  4914.  * only, and would normally not be used by applications.
  4915.  * @param[in] avc a pointer to an arbitrary struct of which the first field is
  4916.  * a pointer to an AVClass struct
  4917.  * @param[in] feature string containing the name of the missing feature
  4918.  * @param[in] want_sample indicates if samples are wanted which exhibit this feature.
  4919.  * If want_sample is non-zero, additional verbage will be added to the log
  4920.  * message which tells the user how to report samples to the development
  4921.  * mailing list.
  4922.  * @deprecated Use avpriv_report_missing_feature() instead.
  4923.  */
  4924. attribute_deprecated
  4925. void av_log_missing_feature(void *avc, const char *feature, int want_sample);
  4926.  
  4927. /**
  4928.  * Log a generic warning message asking for a sample. This function is
  4929.  * intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
  4930.  * only, and would normally not be used by applications.
  4931.  * @param[in] avc a pointer to an arbitrary struct of which the first field is
  4932.  * a pointer to an AVClass struct
  4933.  * @param[in] msg string containing an optional message, or NULL if no message
  4934.  * @deprecated Use avpriv_request_sample() instead.
  4935.  */
  4936. attribute_deprecated
  4937. void av_log_ask_for_sample(void *avc, const char *msg, ...) av_printf_format(2, 3);
  4938. #endif /* FF_API_MISSING_SAMPLE */
  4939.  
  4940. /**
  4941.  * Register the hardware accelerator hwaccel.
  4942.  */
  4943. void av_register_hwaccel(AVHWAccel *hwaccel);
  4944.  
  4945. /**
  4946.  * If hwaccel is NULL, returns the first registered hardware accelerator,
  4947.  * if hwaccel is non-NULL, returns the next registered hardware accelerator
  4948.  * after hwaccel, or NULL if hwaccel is the last one.
  4949.  */
  4950. AVHWAccel *av_hwaccel_next(AVHWAccel *hwaccel);
  4951.  
  4952.  
  4953. /**
  4954.  * Lock operation used by lockmgr
  4955.  */
  4956. enum AVLockOp {
  4957.   AV_LOCK_CREATE,  ///< Create a mutex
  4958.   AV_LOCK_OBTAIN,  ///< Lock the mutex
  4959.   AV_LOCK_RELEASE, ///< Unlock the mutex
  4960.   AV_LOCK_DESTROY, ///< Free mutex resources
  4961. };
  4962.  
  4963. /**
  4964.  * Register a user provided lock manager supporting the operations
  4965.  * specified by AVLockOp. mutex points to a (void *) where the
  4966.  * lockmgr should store/get a pointer to a user allocated mutex. It's
  4967.  * NULL upon AV_LOCK_CREATE and != NULL for all other ops.
  4968.  *
  4969.  * @param cb User defined callback. Note: FFmpeg may invoke calls to this
  4970.  *           callback during the call to av_lockmgr_register().
  4971.  *           Thus, the application must be prepared to handle that.
  4972.  *           If cb is set to NULL the lockmgr will be unregistered.
  4973.  *           Also note that during unregistration the previously registered
  4974.  *           lockmgr callback may also be invoked.
  4975.  */
  4976. int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
  4977.  
  4978. /**
  4979.  * Get the type of the given codec.
  4980.  */
  4981. enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
  4982.  
  4983. /**
  4984.  * Get the name of a codec.
  4985.  * @return  a static string identifying the codec; never NULL
  4986.  */
  4987. const char *avcodec_get_name(enum AVCodecID id);
  4988.  
  4989. /**
  4990.  * @return a positive value if s is open (i.e. avcodec_open2() was called on it
  4991.  * with no corresponding avcodec_close()), 0 otherwise.
  4992.  */
  4993. int avcodec_is_open(AVCodecContext *s);
  4994.  
  4995. /**
  4996.  * @return a non-zero number if codec is an encoder, zero otherwise
  4997.  */
  4998. int av_codec_is_encoder(const AVCodec *codec);
  4999.  
  5000. /**
  5001.  * @return a non-zero number if codec is a decoder, zero otherwise
  5002.  */
  5003. int av_codec_is_decoder(const AVCodec *codec);
  5004.  
  5005. /**
  5006.  * @return descriptor for given codec ID or NULL if no descriptor exists.
  5007.  */
  5008. const AVCodecDescriptor *avcodec_descriptor_get(enum AVCodecID id);
  5009.  
  5010. /**
  5011.  * Iterate over all codec descriptors known to libavcodec.
  5012.  *
  5013.  * @param prev previous descriptor. NULL to get the first descriptor.
  5014.  *
  5015.  * @return next descriptor or NULL after the last descriptor
  5016.  */
  5017. const AVCodecDescriptor *avcodec_descriptor_next(const AVCodecDescriptor *prev);
  5018.  
  5019. /**
  5020.  * @return codec descriptor with the given name or NULL if no such descriptor
  5021.  *         exists.
  5022.  */
  5023. const AVCodecDescriptor *avcodec_descriptor_get_by_name(const char *name);
  5024.  
  5025. /**
  5026.  * @}
  5027.  */
  5028.  
  5029. #endif /* AVCODEC_AVCODEC_H */
  5030.