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  1. /*
  2.  * Copyright (C) 2007 Marco Gerards <marco@gnu.org>
  3.  * Copyright (C) 2009 David Conrad
  4.  * Copyright (C) 2011 Jordi Ortiz
  5.  *
  6.  * This file is part of FFmpeg.
  7.  *
  8.  * FFmpeg is free software; you can redistribute it and/or
  9.  * modify it under the terms of the GNU Lesser General Public
  10.  * License as published by the Free Software Foundation; either
  11.  * version 2.1 of the License, or (at your option) any later version.
  12.  *
  13.  * FFmpeg is distributed in the hope that it will be useful,
  14.  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16.  * Lesser General Public License for more details.
  17.  *
  18.  * You should have received a copy of the GNU Lesser General Public
  19.  * License along with FFmpeg; if not, write to the Free Software
  20.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21.  */
  22.  
  23. /**
  24.  * @file
  25.  * Dirac Decoder
  26.  * @author Marco Gerards <marco@gnu.org>, David Conrad, Jordi Ortiz <nenjordi@gmail.com>
  27.  */
  28.  
  29. #include "avcodec.h"
  30. #include "get_bits.h"
  31. #include "bytestream.h"
  32. #include "internal.h"
  33. #include "golomb.h"
  34. #include "dirac_arith.h"
  35. #include "mpeg12data.h"
  36. #include "libavcodec/mpegvideo.h"
  37. #include "mpegvideoencdsp.h"
  38. #include "dirac_dwt.h"
  39. #include "dirac.h"
  40. #include "diracdsp.h"
  41. #include "videodsp.h"
  42.  
  43. /**
  44.  * The spec limits the number of wavelet decompositions to 4 for both
  45.  * level 1 (VC-2) and 128 (long-gop default).
  46.  * 5 decompositions is the maximum before >16-bit buffers are needed.
  47.  * Schroedinger allows this for DD 9,7 and 13,7 wavelets only, limiting
  48.  * the others to 4 decompositions (or 3 for the fidelity filter).
  49.  *
  50.  * We use this instead of MAX_DECOMPOSITIONS to save some memory.
  51.  */
  52. #define MAX_DWT_LEVELS 5
  53.  
  54. /**
  55.  * The spec limits this to 3 for frame coding, but in practice can be as high as 6
  56.  */
  57. #define MAX_REFERENCE_FRAMES 8
  58. #define MAX_DELAY 5         /* limit for main profile for frame coding (TODO: field coding) */
  59. #define MAX_FRAMES (MAX_REFERENCE_FRAMES + MAX_DELAY + 1)
  60. #define MAX_QUANT 68        /* max quant for VC-2 */
  61. #define MAX_BLOCKSIZE 32    /* maximum xblen/yblen we support */
  62.  
  63. /**
  64.  * DiracBlock->ref flags, if set then the block does MC from the given ref
  65.  */
  66. #define DIRAC_REF_MASK_REF1   1
  67. #define DIRAC_REF_MASK_REF2   2
  68. #define DIRAC_REF_MASK_GLOBAL 4
  69.  
  70. /**
  71.  * Value of Picture.reference when Picture is not a reference picture, but
  72.  * is held for delayed output.
  73.  */
  74. #define DELAYED_PIC_REF 4
  75.  
  76. #define CALC_PADDING(size, depth)                       \
  77.     (((size + (1 << depth) - 1) >> depth) << depth)
  78.  
  79. #define DIVRNDUP(a, b) (((a) + (b) - 1) / (b))
  80.  
  81. typedef struct {
  82.     AVFrame *avframe;
  83.     int interpolated[3];    /* 1 if hpel[] is valid */
  84.     uint8_t *hpel[3][4];
  85.     uint8_t *hpel_base[3][4];
  86.     int reference;
  87. } DiracFrame;
  88.  
  89. typedef struct {
  90.     union {
  91.         int16_t mv[2][2];
  92.         int16_t dc[3];
  93.     } u; /* anonymous unions aren't in C99 :( */
  94.     uint8_t ref;
  95. } DiracBlock;
  96.  
  97. typedef struct SubBand {
  98.     int level;
  99.     int orientation;
  100.     int stride;
  101.     int width;
  102.     int height;
  103.     int quant;
  104.     IDWTELEM *ibuf;
  105.     struct SubBand *parent;
  106.  
  107.     /* for low delay */
  108.     unsigned length;
  109.     const uint8_t *coeff_data;
  110. } SubBand;
  111.  
  112. typedef struct Plane {
  113.     int width;
  114.     int height;
  115.     ptrdiff_t stride;
  116.  
  117.     int idwt_width;
  118.     int idwt_height;
  119.     int idwt_stride;
  120.     IDWTELEM *idwt_buf;
  121.     IDWTELEM *idwt_buf_base;
  122.     IDWTELEM *idwt_tmp;
  123.  
  124.     /* block length */
  125.     uint8_t xblen;
  126.     uint8_t yblen;
  127.     /* block separation (block n+1 starts after this many pixels in block n) */
  128.     uint8_t xbsep;
  129.     uint8_t ybsep;
  130.     /* amount of overspill on each edge (half of the overlap between blocks) */
  131.     uint8_t xoffset;
  132.     uint8_t yoffset;
  133.  
  134.     SubBand band[MAX_DWT_LEVELS][4];
  135. } Plane;
  136.  
  137. typedef struct DiracContext {
  138.     AVCodecContext *avctx;
  139.     MpegvideoEncDSPContext mpvencdsp;
  140.     VideoDSPContext vdsp;
  141.     DiracDSPContext diracdsp;
  142.     GetBitContext gb;
  143.     dirac_source_params source;
  144.     int seen_sequence_header;
  145.     int frame_number;           /* number of the next frame to display       */
  146.     Plane plane[3];
  147.     int chroma_x_shift;
  148.     int chroma_y_shift;
  149.  
  150.     int zero_res;               /* zero residue flag                         */
  151.     int is_arith;               /* whether coeffs use arith or golomb coding */
  152.     int low_delay;              /* use the low delay syntax                  */
  153.     int globalmc_flag;          /* use global motion compensation            */
  154.     int num_refs;               /* number of reference pictures              */
  155.  
  156.     /* wavelet decoding */
  157.     unsigned wavelet_depth;     /* depth of the IDWT                         */
  158.     unsigned wavelet_idx;
  159.  
  160.     /**
  161.      * schroedinger older than 1.0.8 doesn't store
  162.      * quant delta if only one codebook exists in a band
  163.      */
  164.     unsigned old_delta_quant;
  165.     unsigned codeblock_mode;
  166.  
  167.     struct {
  168.         unsigned width;
  169.         unsigned height;
  170.     } codeblock[MAX_DWT_LEVELS+1];
  171.  
  172.     struct {
  173.         unsigned num_x;         /* number of horizontal slices               */
  174.         unsigned num_y;         /* number of vertical slices                 */
  175.         AVRational bytes;       /* average bytes per slice                   */
  176.         uint8_t quant[MAX_DWT_LEVELS][4]; /* [DIRAC_STD] E.1 */
  177.     } lowdelay;
  178.  
  179.     struct {
  180.         int pan_tilt[2];        /* pan/tilt vector                           */
  181.         int zrs[2][2];          /* zoom/rotate/shear matrix                  */
  182.         int perspective[2];     /* perspective vector                        */
  183.         unsigned zrs_exp;
  184.         unsigned perspective_exp;
  185.     } globalmc[2];
  186.  
  187.     /* motion compensation */
  188.     uint8_t mv_precision;       /* [DIRAC_STD] REFS_WT_PRECISION             */
  189.     int16_t weight[2];          /* [DIRAC_STD] REF1_WT and REF2_WT           */
  190.     unsigned weight_log2denom;  /* [DIRAC_STD] REFS_WT_PRECISION             */
  191.  
  192.     int blwidth;                /* number of blocks (horizontally)           */
  193.     int blheight;               /* number of blocks (vertically)             */
  194.     int sbwidth;                /* number of superblocks (horizontally)      */
  195.     int sbheight;               /* number of superblocks (vertically)        */
  196.  
  197.     uint8_t *sbsplit;
  198.     DiracBlock *blmotion;
  199.  
  200.     uint8_t *edge_emu_buffer[4];
  201.     uint8_t *edge_emu_buffer_base;
  202.  
  203.     uint16_t *mctmp;            /* buffer holding the MC data multiplied by OBMC weights */
  204.     uint8_t *mcscratch;
  205.     int buffer_stride;
  206.  
  207.     DECLARE_ALIGNED(16, uint8_t, obmc_weight)[3][MAX_BLOCKSIZE*MAX_BLOCKSIZE];
  208.  
  209.     void (*put_pixels_tab[4])(uint8_t *dst, const uint8_t *src[5], int stride, int h);
  210.     void (*avg_pixels_tab[4])(uint8_t *dst, const uint8_t *src[5], int stride, int h);
  211.     void (*add_obmc)(uint16_t *dst, const uint8_t *src, int stride, const uint8_t *obmc_weight, int yblen);
  212.     dirac_weight_func weight_func;
  213.     dirac_biweight_func biweight_func;
  214.  
  215.     DiracFrame *current_picture;
  216.     DiracFrame *ref_pics[2];
  217.  
  218.     DiracFrame *ref_frames[MAX_REFERENCE_FRAMES+1];
  219.     DiracFrame *delay_frames[MAX_DELAY+1];
  220.     DiracFrame all_frames[MAX_FRAMES];
  221. } DiracContext;
  222.  
  223. /**
  224.  * Dirac Specification ->
  225.  * Parse code values. 9.6.1 Table 9.1
  226.  */
  227. enum dirac_parse_code {
  228.     pc_seq_header         = 0x00,
  229.     pc_eos                = 0x10,
  230.     pc_aux_data           = 0x20,
  231.     pc_padding            = 0x30,
  232. };
  233.  
  234. enum dirac_subband {
  235.     subband_ll = 0,
  236.     subband_hl = 1,
  237.     subband_lh = 2,
  238.     subband_hh = 3,
  239.     subband_nb,
  240. };
  241.  
  242. static const uint8_t default_qmat[][4][4] = {
  243.     { { 5,  3,  3,  0}, { 0,  4,  4,  1}, { 0,  5,  5,  2}, { 0,  6,  6,  3} },
  244.     { { 4,  2,  2,  0}, { 0,  4,  4,  2}, { 0,  5,  5,  3}, { 0,  7,  7,  5} },
  245.     { { 5,  3,  3,  0}, { 0,  4,  4,  1}, { 0,  5,  5,  2}, { 0,  6,  6,  3} },
  246.     { { 8,  4,  4,  0}, { 0,  4,  4,  0}, { 0,  4,  4,  0}, { 0,  4,  4,  0} },
  247.     { { 8,  4,  4,  0}, { 0,  4,  4,  0}, { 0,  4,  4,  0}, { 0,  4,  4,  0} },
  248.     { { 0,  4,  4,  8}, { 0,  8,  8, 12}, { 0, 13, 13, 17}, { 0, 17, 17, 21} },
  249.     { { 3,  1,  1,  0}, { 0,  4,  4,  2}, { 0,  6,  6,  5}, { 0,  9,  9,  7} },
  250. };
  251.  
  252. static const int qscale_tab[MAX_QUANT+1] = {
  253.     4,     5,     6,     7,     8,    10,    11,    13,
  254.     16,    19,    23,    27,    32,    38,    45,    54,
  255.     64,    76,    91,   108,   128,   152,   181,   215,
  256.     256,   304,   362,   431,   512,   609,   724,   861,
  257.     1024,  1218,  1448,  1722,  2048,  2435,  2896,  3444,
  258.     4096,  4871,  5793,  6889,  8192,  9742, 11585, 13777,
  259.     16384, 19484, 23170, 27554, 32768, 38968, 46341, 55109,
  260.     65536, 77936
  261. };
  262.  
  263. static const int qoffset_intra_tab[MAX_QUANT+1] = {
  264.     1,     2,     3,     4,     4,     5,     6,     7,
  265.     8,    10,    12,    14,    16,    19,    23,    27,
  266.     32,    38,    46,    54,    64,    76,    91,   108,
  267.     128,   152,   181,   216,   256,   305,   362,   431,
  268.     512,   609,   724,   861,  1024,  1218,  1448,  1722,
  269.     2048,  2436,  2897,  3445,  4096,  4871,  5793,  6889,
  270.     8192,  9742, 11585, 13777, 16384, 19484, 23171, 27555,
  271.     32768, 38968
  272. };
  273.  
  274. static const int qoffset_inter_tab[MAX_QUANT+1] = {
  275.     1,     2,     2,     3,     3,     4,     4,     5,
  276.     6,     7,     9,    10,    12,    14,    17,    20,
  277.     24,    29,    34,    41,    48,    57,    68,    81,
  278.     96,   114,   136,   162,   192,   228,   272,   323,
  279.     384,   457,   543,   646,   768,   913,  1086,  1292,
  280.     1536,  1827,  2172,  2583,  3072,  3653,  4344,  5166,
  281.     6144,  7307,  8689, 10333, 12288, 14613, 17378, 20666,
  282.     24576, 29226
  283. };
  284.  
  285. /* magic number division by 3 from schroedinger */
  286. static inline int divide3(int x)
  287. {
  288.     return ((x+1)*21845 + 10922) >> 16;
  289. }
  290.  
  291. static DiracFrame *remove_frame(DiracFrame *framelist[], int picnum)
  292. {
  293.     DiracFrame *remove_pic = NULL;
  294.     int i, remove_idx = -1;
  295.  
  296.     for (i = 0; framelist[i]; i++)
  297.         if (framelist[i]->avframe->display_picture_number == picnum) {
  298.             remove_pic = framelist[i];
  299.             remove_idx = i;
  300.         }
  301.  
  302.     if (remove_pic)
  303.         for (i = remove_idx; framelist[i]; i++)
  304.             framelist[i] = framelist[i+1];
  305.  
  306.     return remove_pic;
  307. }
  308.  
  309. static int add_frame(DiracFrame *framelist[], int maxframes, DiracFrame *frame)
  310. {
  311.     int i;
  312.     for (i = 0; i < maxframes; i++)
  313.         if (!framelist[i]) {
  314.             framelist[i] = frame;
  315.             return 0;
  316.         }
  317.     return -1;
  318. }
  319.  
  320. static int alloc_sequence_buffers(DiracContext *s)
  321. {
  322.     int sbwidth  = DIVRNDUP(s->source.width,  4);
  323.     int sbheight = DIVRNDUP(s->source.height, 4);
  324.     int i, w, h, top_padding;
  325.  
  326.     /* todo: think more about this / use or set Plane here */
  327.     for (i = 0; i < 3; i++) {
  328.         int max_xblen = MAX_BLOCKSIZE >> (i ? s->chroma_x_shift : 0);
  329.         int max_yblen = MAX_BLOCKSIZE >> (i ? s->chroma_y_shift : 0);
  330.         w = s->source.width  >> (i ? s->chroma_x_shift : 0);
  331.         h = s->source.height >> (i ? s->chroma_y_shift : 0);
  332.  
  333.         /* we allocate the max we support here since num decompositions can
  334.          * change from frame to frame. Stride is aligned to 16 for SIMD, and
  335.          * 1<<MAX_DWT_LEVELS top padding to avoid if(y>0) in arith decoding
  336.          * MAX_BLOCKSIZE padding for MC: blocks can spill up to half of that
  337.          * on each side */
  338.         top_padding = FFMAX(1<<MAX_DWT_LEVELS, max_yblen/2);
  339.         w = FFALIGN(CALC_PADDING(w, MAX_DWT_LEVELS), 8); /* FIXME: Should this be 16 for SSE??? */
  340.         h = top_padding + CALC_PADDING(h, MAX_DWT_LEVELS) + max_yblen/2;
  341.  
  342.         s->plane[i].idwt_buf_base = av_mallocz_array((w+max_xblen), h * sizeof(IDWTELEM));
  343.         s->plane[i].idwt_tmp      = av_malloc_array((w+16), sizeof(IDWTELEM));
  344.         s->plane[i].idwt_buf      = s->plane[i].idwt_buf_base + top_padding*w;
  345.         if (!s->plane[i].idwt_buf_base || !s->plane[i].idwt_tmp)
  346.             return AVERROR(ENOMEM);
  347.     }
  348.  
  349.     /* fixme: allocate using real stride here */
  350.     s->sbsplit  = av_malloc_array(sbwidth, sbheight);
  351.     s->blmotion = av_malloc_array(sbwidth, sbheight * 16 * sizeof(*s->blmotion));
  352.  
  353.     if (!s->sbsplit || !s->blmotion)
  354.         return AVERROR(ENOMEM);
  355.     return 0;
  356. }
  357.  
  358. static int alloc_buffers(DiracContext *s, int stride)
  359. {
  360.     int w = s->source.width;
  361.     int h = s->source.height;
  362.  
  363.     av_assert0(stride >= w);
  364.     stride += 64;
  365.  
  366.     if (s->buffer_stride >= stride)
  367.         return 0;
  368.     s->buffer_stride = 0;
  369.  
  370.     av_freep(&s->edge_emu_buffer_base);
  371.     memset(s->edge_emu_buffer, 0, sizeof(s->edge_emu_buffer));
  372.     av_freep(&s->mctmp);
  373.     av_freep(&s->mcscratch);
  374.  
  375.     s->edge_emu_buffer_base = av_malloc_array(stride, MAX_BLOCKSIZE);
  376.  
  377.     s->mctmp     = av_malloc_array((stride+MAX_BLOCKSIZE), (h+MAX_BLOCKSIZE) * sizeof(*s->mctmp));
  378.     s->mcscratch = av_malloc_array(stride, MAX_BLOCKSIZE);
  379.  
  380.     if (!s->edge_emu_buffer_base || !s->mctmp || !s->mcscratch)
  381.         return AVERROR(ENOMEM);
  382.  
  383.     s->buffer_stride = stride;
  384.     return 0;
  385. }
  386.  
  387. static void free_sequence_buffers(DiracContext *s)
  388. {
  389.     int i, j, k;
  390.  
  391.     for (i = 0; i < MAX_FRAMES; i++) {
  392.         if (s->all_frames[i].avframe->data[0]) {
  393.             av_frame_unref(s->all_frames[i].avframe);
  394.             memset(s->all_frames[i].interpolated, 0, sizeof(s->all_frames[i].interpolated));
  395.         }
  396.  
  397.         for (j = 0; j < 3; j++)
  398.             for (k = 1; k < 4; k++)
  399.                 av_freep(&s->all_frames[i].hpel_base[j][k]);
  400.     }
  401.  
  402.     memset(s->ref_frames, 0, sizeof(s->ref_frames));
  403.     memset(s->delay_frames, 0, sizeof(s->delay_frames));
  404.  
  405.     for (i = 0; i < 3; i++) {
  406.         av_freep(&s->plane[i].idwt_buf_base);
  407.         av_freep(&s->plane[i].idwt_tmp);
  408.     }
  409.  
  410.     s->buffer_stride = 0;
  411.     av_freep(&s->sbsplit);
  412.     av_freep(&s->blmotion);
  413.     av_freep(&s->edge_emu_buffer_base);
  414.  
  415.     av_freep(&s->mctmp);
  416.     av_freep(&s->mcscratch);
  417. }
  418.  
  419. static av_cold int dirac_decode_init(AVCodecContext *avctx)
  420. {
  421.     DiracContext *s = avctx->priv_data;
  422.     int i;
  423.  
  424.     s->avctx = avctx;
  425.     s->frame_number = -1;
  426.  
  427.     ff_diracdsp_init(&s->diracdsp);
  428.     ff_mpegvideoencdsp_init(&s->mpvencdsp, avctx);
  429.     ff_videodsp_init(&s->vdsp, 8);
  430.  
  431.     for (i = 0; i < MAX_FRAMES; i++) {
  432.         s->all_frames[i].avframe = av_frame_alloc();
  433.         if (!s->all_frames[i].avframe) {
  434.             while (i > 0)
  435.                 av_frame_free(&s->all_frames[--i].avframe);
  436.             return AVERROR(ENOMEM);
  437.         }
  438.     }
  439.  
  440.     return 0;
  441. }
  442.  
  443. static void dirac_decode_flush(AVCodecContext *avctx)
  444. {
  445.     DiracContext *s = avctx->priv_data;
  446.     free_sequence_buffers(s);
  447.     s->seen_sequence_header = 0;
  448.     s->frame_number = -1;
  449. }
  450.  
  451. static av_cold int dirac_decode_end(AVCodecContext *avctx)
  452. {
  453.     DiracContext *s = avctx->priv_data;
  454.     int i;
  455.  
  456.     dirac_decode_flush(avctx);
  457.     for (i = 0; i < MAX_FRAMES; i++)
  458.         av_frame_free(&s->all_frames[i].avframe);
  459.  
  460.     return 0;
  461. }
  462.  
  463. #define SIGN_CTX(x) (CTX_SIGN_ZERO + ((x) > 0) - ((x) < 0))
  464.  
  465. static inline void coeff_unpack_arith(DiracArith *c, int qfactor, int qoffset,
  466.                                       SubBand *b, IDWTELEM *buf, int x, int y)
  467. {
  468.     int coeff, sign;
  469.     int sign_pred = 0;
  470.     int pred_ctx = CTX_ZPZN_F1;
  471.  
  472.     /* Check if the parent subband has a 0 in the corresponding position */
  473.     if (b->parent)
  474.         pred_ctx += !!b->parent->ibuf[b->parent->stride * (y>>1) + (x>>1)] << 1;
  475.  
  476.     if (b->orientation == subband_hl)
  477.         sign_pred = buf[-b->stride];
  478.  
  479.     /* Determine if the pixel has only zeros in its neighbourhood */
  480.     if (x) {
  481.         pred_ctx += !(buf[-1] | buf[-b->stride] | buf[-1-b->stride]);
  482.         if (b->orientation == subband_lh)
  483.             sign_pred = buf[-1];
  484.     } else {
  485.         pred_ctx += !buf[-b->stride];
  486.     }
  487.  
  488.     coeff = dirac_get_arith_uint(c, pred_ctx, CTX_COEFF_DATA);
  489.     if (coeff) {
  490.         coeff = (coeff * qfactor + qoffset + 2) >> 2;
  491.         sign  = dirac_get_arith_bit(c, SIGN_CTX(sign_pred));
  492.         coeff = (coeff ^ -sign) + sign;
  493.     }
  494.     *buf = coeff;
  495. }
  496.  
  497. static inline int coeff_unpack_golomb(GetBitContext *gb, int qfactor, int qoffset)
  498. {
  499.     int sign, coeff;
  500.  
  501.     coeff = svq3_get_ue_golomb(gb);
  502.     if (coeff) {
  503.         coeff = (coeff * qfactor + qoffset + 2) >> 2;
  504.         sign  = get_bits1(gb);
  505.         coeff = (coeff ^ -sign) + sign;
  506.     }
  507.     return coeff;
  508. }
  509.  
  510. /**
  511.  * Decode the coeffs in the rectangle defined by left, right, top, bottom
  512.  * [DIRAC_STD] 13.4.3.2 Codeblock unpacking loop. codeblock()
  513.  */
  514. static inline void codeblock(DiracContext *s, SubBand *b,
  515.                              GetBitContext *gb, DiracArith *c,
  516.                              int left, int right, int top, int bottom,
  517.                              int blockcnt_one, int is_arith)
  518. {
  519.     int x, y, zero_block;
  520.     int qoffset, qfactor;
  521.     IDWTELEM *buf;
  522.  
  523.     /* check for any coded coefficients in this codeblock */
  524.     if (!blockcnt_one) {
  525.         if (is_arith)
  526.             zero_block = dirac_get_arith_bit(c, CTX_ZERO_BLOCK);
  527.         else
  528.             zero_block = get_bits1(gb);
  529.  
  530.         if (zero_block)
  531.             return;
  532.     }
  533.  
  534.     if (s->codeblock_mode && !(s->old_delta_quant && blockcnt_one)) {
  535.         int quant = b->quant;
  536.         if (is_arith)
  537.             quant += dirac_get_arith_int(c, CTX_DELTA_Q_F, CTX_DELTA_Q_DATA);
  538.         else
  539.             quant += dirac_get_se_golomb(gb);
  540.         if (quant < 0) {
  541.             av_log(s->avctx, AV_LOG_ERROR, "Invalid quant\n");
  542.             return;
  543.         }
  544.         b->quant = quant;
  545.     }
  546.  
  547.     b->quant = FFMIN(b->quant, MAX_QUANT);
  548.  
  549.     qfactor = qscale_tab[b->quant];
  550.     /* TODO: context pointer? */
  551.     if (!s->num_refs)
  552.         qoffset = qoffset_intra_tab[b->quant];
  553.     else
  554.         qoffset = qoffset_inter_tab[b->quant];
  555.  
  556.     buf = b->ibuf + top * b->stride;
  557.     for (y = top; y < bottom; y++) {
  558.         for (x = left; x < right; x++) {
  559.             /* [DIRAC_STD] 13.4.4 Subband coefficients. coeff_unpack() */
  560.             if (is_arith)
  561.                 coeff_unpack_arith(c, qfactor, qoffset, b, buf+x, x, y);
  562.             else
  563.                 buf[x] = coeff_unpack_golomb(gb, qfactor, qoffset);
  564.         }
  565.         buf += b->stride;
  566.     }
  567. }
  568.  
  569. /**
  570.  * Dirac Specification ->
  571.  * 13.3 intra_dc_prediction(band)
  572.  */
  573. static inline void intra_dc_prediction(SubBand *b)
  574. {
  575.     IDWTELEM *buf = b->ibuf;
  576.     int x, y;
  577.  
  578.     for (x = 1; x < b->width; x++)
  579.         buf[x] += buf[x-1];
  580.     buf += b->stride;
  581.  
  582.     for (y = 1; y < b->height; y++) {
  583.         buf[0] += buf[-b->stride];
  584.  
  585.         for (x = 1; x < b->width; x++) {
  586.             int pred = buf[x - 1] + buf[x - b->stride] + buf[x - b->stride-1];
  587.             buf[x]  += divide3(pred);
  588.         }
  589.         buf += b->stride;
  590.     }
  591. }
  592.  
  593. /**
  594.  * Dirac Specification ->
  595.  * 13.4.2 Non-skipped subbands.  subband_coeffs()
  596.  */
  597. static av_always_inline void decode_subband_internal(DiracContext *s, SubBand *b, int is_arith)
  598. {
  599.     int cb_x, cb_y, left, right, top, bottom;
  600.     DiracArith c;
  601.     GetBitContext gb;
  602.     int cb_width  = s->codeblock[b->level + (b->orientation != subband_ll)].width;
  603.     int cb_height = s->codeblock[b->level + (b->orientation != subband_ll)].height;
  604.     int blockcnt_one = (cb_width + cb_height) == 2;
  605.  
  606.     if (!b->length)
  607.         return;
  608.  
  609.     init_get_bits8(&gb, b->coeff_data, b->length);
  610.  
  611.     if (is_arith)
  612.         ff_dirac_init_arith_decoder(&c, &gb, b->length);
  613.  
  614.     top = 0;
  615.     for (cb_y = 0; cb_y < cb_height; cb_y++) {
  616.         bottom = (b->height * (cb_y+1LL)) / cb_height;
  617.         left = 0;
  618.         for (cb_x = 0; cb_x < cb_width; cb_x++) {
  619.             right = (b->width * (cb_x+1LL)) / cb_width;
  620.             codeblock(s, b, &gb, &c, left, right, top, bottom, blockcnt_one, is_arith);
  621.             left = right;
  622.         }
  623.         top = bottom;
  624.     }
  625.  
  626.     if (b->orientation == subband_ll && s->num_refs == 0)
  627.         intra_dc_prediction(b);
  628. }
  629.  
  630. static int decode_subband_arith(AVCodecContext *avctx, void *b)
  631. {
  632.     DiracContext *s = avctx->priv_data;
  633.     decode_subband_internal(s, b, 1);
  634.     return 0;
  635. }
  636.  
  637. static int decode_subband_golomb(AVCodecContext *avctx, void *arg)
  638. {
  639.     DiracContext *s = avctx->priv_data;
  640.     SubBand **b     = arg;
  641.     decode_subband_internal(s, *b, 0);
  642.     return 0;
  643. }
  644.  
  645. /**
  646.  * Dirac Specification ->
  647.  * [DIRAC_STD] 13.4.1 core_transform_data()
  648.  */
  649. static void decode_component(DiracContext *s, int comp)
  650. {
  651.     AVCodecContext *avctx = s->avctx;
  652.     SubBand *bands[3*MAX_DWT_LEVELS+1];
  653.     enum dirac_subband orientation;
  654.     int level, num_bands = 0;
  655.  
  656.     /* Unpack all subbands at all levels. */
  657.     for (level = 0; level < s->wavelet_depth; level++) {
  658.         for (orientation = !!level; orientation < 4; orientation++) {
  659.             SubBand *b = &s->plane[comp].band[level][orientation];
  660.             bands[num_bands++] = b;
  661.  
  662.             align_get_bits(&s->gb);
  663.             /* [DIRAC_STD] 13.4.2 subband() */
  664.             b->length = svq3_get_ue_golomb(&s->gb);
  665.             if (b->length) {
  666.                 b->quant = svq3_get_ue_golomb(&s->gb);
  667.                 align_get_bits(&s->gb);
  668.                 b->coeff_data = s->gb.buffer + get_bits_count(&s->gb)/8;
  669.                 b->length = FFMIN(b->length, FFMAX(get_bits_left(&s->gb)/8, 0));
  670.                 skip_bits_long(&s->gb, b->length*8);
  671.             }
  672.         }
  673.         /* arithmetic coding has inter-level dependencies, so we can only execute one level at a time */
  674.         if (s->is_arith)
  675.             avctx->execute(avctx, decode_subband_arith, &s->plane[comp].band[level][!!level],
  676.                            NULL, 4-!!level, sizeof(SubBand));
  677.     }
  678.     /* golomb coding has no inter-level dependencies, so we can execute all subbands in parallel */
  679.     if (!s->is_arith)
  680.         avctx->execute(avctx, decode_subband_golomb, bands, NULL, num_bands, sizeof(SubBand*));
  681. }
  682.  
  683. /* [DIRAC_STD] 13.5.5.2 Luma slice subband data. luma_slice_band(level,orient,sx,sy) --> if b2 == NULL */
  684. /* [DIRAC_STD] 13.5.5.3 Chroma slice subband data. chroma_slice_band(level,orient,sx,sy) --> if b2 != NULL */
  685. static void lowdelay_subband(DiracContext *s, GetBitContext *gb, int quant,
  686.                              int slice_x, int slice_y, int bits_end,
  687.                              SubBand *b1, SubBand *b2)
  688. {
  689.     int left   = b1->width  * slice_x    / s->lowdelay.num_x;
  690.     int right  = b1->width  *(slice_x+1) / s->lowdelay.num_x;
  691.     int top    = b1->height * slice_y    / s->lowdelay.num_y;
  692.     int bottom = b1->height *(slice_y+1) / s->lowdelay.num_y;
  693.  
  694.     int qfactor = qscale_tab[FFMIN(quant, MAX_QUANT)];
  695.     int qoffset = qoffset_intra_tab[FFMIN(quant, MAX_QUANT)];
  696.  
  697.     IDWTELEM *buf1 =      b1->ibuf + top * b1->stride;
  698.     IDWTELEM *buf2 = b2 ? b2->ibuf + top * b2->stride : NULL;
  699.     int x, y;
  700.     /* we have to constantly check for overread since the spec explicitly
  701.        requires this, with the meaning that all remaining coeffs are set to 0 */
  702.     if (get_bits_count(gb) >= bits_end)
  703.         return;
  704.  
  705.     for (y = top; y < bottom; y++) {
  706.         for (x = left; x < right; x++) {
  707.             buf1[x] = coeff_unpack_golomb(gb, qfactor, qoffset);
  708.             if (get_bits_count(gb) >= bits_end)
  709.                 return;
  710.             if (buf2) {
  711.                 buf2[x] = coeff_unpack_golomb(gb, qfactor, qoffset);
  712.                 if (get_bits_count(gb) >= bits_end)
  713.                     return;
  714.             }
  715.         }
  716.         buf1 += b1->stride;
  717.         if (buf2)
  718.             buf2 += b2->stride;
  719.     }
  720. }
  721.  
  722. struct lowdelay_slice {
  723.     GetBitContext gb;
  724.     int slice_x;
  725.     int slice_y;
  726.     int bytes;
  727. };
  728.  
  729.  
  730. /**
  731.  * Dirac Specification ->
  732.  * 13.5.2 Slices. slice(sx,sy)
  733.  */
  734. static int decode_lowdelay_slice(AVCodecContext *avctx, void *arg)
  735. {
  736.     DiracContext *s = avctx->priv_data;
  737.     struct lowdelay_slice *slice = arg;
  738.     GetBitContext *gb = &slice->gb;
  739.     enum dirac_subband orientation;
  740.     int level, quant, chroma_bits, chroma_end;
  741.  
  742.     int quant_base  = get_bits(gb, 7); /*[DIRAC_STD] qindex */
  743.     int length_bits = av_log2(8 * slice->bytes)+1;
  744.     int luma_bits   = get_bits_long(gb, length_bits);
  745.     int luma_end    = get_bits_count(gb) + FFMIN(luma_bits, get_bits_left(gb));
  746.  
  747.     /* [DIRAC_STD] 13.5.5.2 luma_slice_band */
  748.     for (level = 0; level < s->wavelet_depth; level++)
  749.         for (orientation = !!level; orientation < 4; orientation++) {
  750.             quant = FFMAX(quant_base - s->lowdelay.quant[level][orientation], 0);
  751.             lowdelay_subband(s, gb, quant, slice->slice_x, slice->slice_y, luma_end,
  752.                              &s->plane[0].band[level][orientation], NULL);
  753.         }
  754.  
  755.     /* consume any unused bits from luma */
  756.     skip_bits_long(gb, get_bits_count(gb) - luma_end);
  757.  
  758.     chroma_bits = 8*slice->bytes - 7 - length_bits - luma_bits;
  759.     chroma_end  = get_bits_count(gb) + FFMIN(chroma_bits, get_bits_left(gb));
  760.     /* [DIRAC_STD] 13.5.5.3 chroma_slice_band */
  761.     for (level = 0; level < s->wavelet_depth; level++)
  762.         for (orientation = !!level; orientation < 4; orientation++) {
  763.             quant = FFMAX(quant_base - s->lowdelay.quant[level][orientation], 0);
  764.             lowdelay_subband(s, gb, quant, slice->slice_x, slice->slice_y, chroma_end,
  765.                              &s->plane[1].band[level][orientation],
  766.                              &s->plane[2].band[level][orientation]);
  767.         }
  768.  
  769.     return 0;
  770. }
  771.  
  772. /**
  773.  * Dirac Specification ->
  774.  * 13.5.1 low_delay_transform_data()
  775.  */
  776. static int decode_lowdelay(DiracContext *s)
  777. {
  778.     AVCodecContext *avctx = s->avctx;
  779.     int slice_x, slice_y, bytes, bufsize;
  780.     const uint8_t *buf;
  781.     struct lowdelay_slice *slices;
  782.     int slice_num = 0;
  783.  
  784.     slices = av_mallocz_array(s->lowdelay.num_x, s->lowdelay.num_y * sizeof(struct lowdelay_slice));
  785.     if (!slices)
  786.         return AVERROR(ENOMEM);
  787.  
  788.     align_get_bits(&s->gb);
  789.     /*[DIRAC_STD] 13.5.2 Slices. slice(sx,sy) */
  790.     buf = s->gb.buffer + get_bits_count(&s->gb)/8;
  791.     bufsize = get_bits_left(&s->gb);
  792.  
  793.     for (slice_y = 0; bufsize > 0 && slice_y < s->lowdelay.num_y; slice_y++)
  794.         for (slice_x = 0; bufsize > 0 && slice_x < s->lowdelay.num_x; slice_x++) {
  795.             bytes = (slice_num+1) * s->lowdelay.bytes.num / s->lowdelay.bytes.den
  796.                 - slice_num    * s->lowdelay.bytes.num / s->lowdelay.bytes.den;
  797.  
  798.             slices[slice_num].bytes   = bytes;
  799.             slices[slice_num].slice_x = slice_x;
  800.             slices[slice_num].slice_y = slice_y;
  801.             init_get_bits(&slices[slice_num].gb, buf, bufsize);
  802.             slice_num++;
  803.  
  804.             buf     += bytes;
  805.             if (bufsize/8 >= bytes)
  806.                 bufsize -= bytes*8;
  807.             else
  808.                 bufsize = 0;
  809.         }
  810.  
  811.     avctx->execute(avctx, decode_lowdelay_slice, slices, NULL, slice_num,
  812.                    sizeof(struct lowdelay_slice)); /* [DIRAC_STD] 13.5.2 Slices */
  813.     intra_dc_prediction(&s->plane[0].band[0][0]);  /* [DIRAC_STD] 13.3 intra_dc_prediction() */
  814.     intra_dc_prediction(&s->plane[1].band[0][0]);  /* [DIRAC_STD] 13.3 intra_dc_prediction() */
  815.     intra_dc_prediction(&s->plane[2].band[0][0]);  /* [DIRAC_STD] 13.3 intra_dc_prediction() */
  816.     av_free(slices);
  817.     return 0;
  818. }
  819.  
  820. static void init_planes(DiracContext *s)
  821. {
  822.     int i, w, h, level, orientation;
  823.  
  824.     for (i = 0; i < 3; i++) {
  825.         Plane *p = &s->plane[i];
  826.  
  827.         p->width       = s->source.width  >> (i ? s->chroma_x_shift : 0);
  828.         p->height      = s->source.height >> (i ? s->chroma_y_shift : 0);
  829.         p->idwt_width  = w = CALC_PADDING(p->width , s->wavelet_depth);
  830.         p->idwt_height = h = CALC_PADDING(p->height, s->wavelet_depth);
  831.         p->idwt_stride = FFALIGN(p->idwt_width, 8);
  832.  
  833.         for (level = s->wavelet_depth-1; level >= 0; level--) {
  834.             w = w>>1;
  835.             h = h>>1;
  836.             for (orientation = !!level; orientation < 4; orientation++) {
  837.                 SubBand *b = &p->band[level][orientation];
  838.  
  839.                 b->ibuf   = p->idwt_buf;
  840.                 b->level  = level;
  841.                 b->stride = p->idwt_stride << (s->wavelet_depth - level);
  842.                 b->width  = w;
  843.                 b->height = h;
  844.                 b->orientation = orientation;
  845.  
  846.                 if (orientation & 1)
  847.                     b->ibuf += w;
  848.                 if (orientation > 1)
  849.                     b->ibuf += b->stride>>1;
  850.  
  851.                 if (level)
  852.                     b->parent = &p->band[level-1][orientation];
  853.             }
  854.         }
  855.  
  856.         if (i > 0) {
  857.             p->xblen = s->plane[0].xblen >> s->chroma_x_shift;
  858.             p->yblen = s->plane[0].yblen >> s->chroma_y_shift;
  859.             p->xbsep = s->plane[0].xbsep >> s->chroma_x_shift;
  860.             p->ybsep = s->plane[0].ybsep >> s->chroma_y_shift;
  861.         }
  862.  
  863.         p->xoffset = (p->xblen - p->xbsep)/2;
  864.         p->yoffset = (p->yblen - p->ybsep)/2;
  865.     }
  866. }
  867.  
  868. /**
  869.  * Unpack the motion compensation parameters
  870.  * Dirac Specification ->
  871.  * 11.2 Picture prediction data. picture_prediction()
  872.  */
  873. static int dirac_unpack_prediction_parameters(DiracContext *s)
  874. {
  875.     static const uint8_t default_blen[] = { 4, 12, 16, 24 };
  876.  
  877.     GetBitContext *gb = &s->gb;
  878.     unsigned idx, ref;
  879.  
  880.     align_get_bits(gb);
  881.     /* [DIRAC_STD] 11.2.2 Block parameters. block_parameters() */
  882.     /* Luma and Chroma are equal. 11.2.3 */
  883.     idx = svq3_get_ue_golomb(gb); /* [DIRAC_STD] index */
  884.  
  885.     if (idx > 4) {
  886.         av_log(s->avctx, AV_LOG_ERROR, "Block prediction index too high\n");
  887.         return AVERROR_INVALIDDATA;
  888.     }
  889.  
  890.     if (idx == 0) {
  891.         s->plane[0].xblen = svq3_get_ue_golomb(gb);
  892.         s->plane[0].yblen = svq3_get_ue_golomb(gb);
  893.         s->plane[0].xbsep = svq3_get_ue_golomb(gb);
  894.         s->plane[0].ybsep = svq3_get_ue_golomb(gb);
  895.     } else {
  896.         /*[DIRAC_STD] preset_block_params(index). Table 11.1 */
  897.         s->plane[0].xblen = default_blen[idx-1];
  898.         s->plane[0].yblen = default_blen[idx-1];
  899.         s->plane[0].xbsep = 4 * idx;
  900.         s->plane[0].ybsep = 4 * idx;
  901.     }
  902.     /*[DIRAC_STD] 11.2.4 motion_data_dimensions()
  903.       Calculated in function dirac_unpack_block_motion_data */
  904.  
  905.     if (s->plane[0].xblen % (1 << s->chroma_x_shift) != 0 ||
  906.         s->plane[0].yblen % (1 << s->chroma_y_shift) != 0 ||
  907.         !s->plane[0].xblen || !s->plane[0].yblen) {
  908.         av_log(s->avctx, AV_LOG_ERROR,
  909.                "invalid x/y block length (%d/%d) for x/y chroma shift (%d/%d)\n",
  910.                s->plane[0].xblen, s->plane[0].yblen, s->chroma_x_shift, s->chroma_y_shift);
  911.         return AVERROR_INVALIDDATA;
  912.     }
  913.     if (!s->plane[0].xbsep || !s->plane[0].ybsep || s->plane[0].xbsep < s->plane[0].xblen/2 || s->plane[0].ybsep < s->plane[0].yblen/2) {
  914.         av_log(s->avctx, AV_LOG_ERROR, "Block separation too small\n");
  915.         return AVERROR_INVALIDDATA;
  916.     }
  917.     if (s->plane[0].xbsep > s->plane[0].xblen || s->plane[0].ybsep > s->plane[0].yblen) {
  918.         av_log(s->avctx, AV_LOG_ERROR, "Block separation greater than size\n");
  919.         return AVERROR_INVALIDDATA;
  920.     }
  921.     if (FFMAX(s->plane[0].xblen, s->plane[0].yblen) > MAX_BLOCKSIZE) {
  922.         av_log(s->avctx, AV_LOG_ERROR, "Unsupported large block size\n");
  923.         return AVERROR_PATCHWELCOME;
  924.     }
  925.  
  926.     /*[DIRAC_STD] 11.2.5 Motion vector precision. motion_vector_precision()
  927.       Read motion vector precision */
  928.     s->mv_precision = svq3_get_ue_golomb(gb);
  929.     if (s->mv_precision > 3) {
  930.         av_log(s->avctx, AV_LOG_ERROR, "MV precision finer than eighth-pel\n");
  931.         return AVERROR_INVALIDDATA;
  932.     }
  933.  
  934.     /*[DIRAC_STD] 11.2.6 Global motion. global_motion()
  935.       Read the global motion compensation parameters */
  936.     s->globalmc_flag = get_bits1(gb);
  937.     if (s->globalmc_flag) {
  938.         memset(s->globalmc, 0, sizeof(s->globalmc));
  939.         /* [DIRAC_STD] pan_tilt(gparams) */
  940.         for (ref = 0; ref < s->num_refs; ref++) {
  941.             if (get_bits1(gb)) {
  942.                 s->globalmc[ref].pan_tilt[0] = dirac_get_se_golomb(gb);
  943.                 s->globalmc[ref].pan_tilt[1] = dirac_get_se_golomb(gb);
  944.             }
  945.             /* [DIRAC_STD] zoom_rotate_shear(gparams)
  946.                zoom/rotation/shear parameters */
  947.             if (get_bits1(gb)) {
  948.                 s->globalmc[ref].zrs_exp   = svq3_get_ue_golomb(gb);
  949.                 s->globalmc[ref].zrs[0][0] = dirac_get_se_golomb(gb);
  950.                 s->globalmc[ref].zrs[0][1] = dirac_get_se_golomb(gb);
  951.                 s->globalmc[ref].zrs[1][0] = dirac_get_se_golomb(gb);
  952.                 s->globalmc[ref].zrs[1][1] = dirac_get_se_golomb(gb);
  953.             } else {
  954.                 s->globalmc[ref].zrs[0][0] = 1;
  955.                 s->globalmc[ref].zrs[1][1] = 1;
  956.             }
  957.             /* [DIRAC_STD] perspective(gparams) */
  958.             if (get_bits1(gb)) {
  959.                 s->globalmc[ref].perspective_exp = svq3_get_ue_golomb(gb);
  960.                 s->globalmc[ref].perspective[0]  = dirac_get_se_golomb(gb);
  961.                 s->globalmc[ref].perspective[1]  = dirac_get_se_golomb(gb);
  962.             }
  963.         }
  964.     }
  965.  
  966.     /*[DIRAC_STD] 11.2.7 Picture prediction mode. prediction_mode()
  967.       Picture prediction mode, not currently used. */
  968.     if (svq3_get_ue_golomb(gb)) {
  969.         av_log(s->avctx, AV_LOG_ERROR, "Unknown picture prediction mode\n");
  970.         return AVERROR_INVALIDDATA;
  971.     }
  972.  
  973.     /* [DIRAC_STD] 11.2.8 Reference picture weight. reference_picture_weights()
  974.        just data read, weight calculation will be done later on. */
  975.     s->weight_log2denom = 1;
  976.     s->weight[0]        = 1;
  977.     s->weight[1]        = 1;
  978.  
  979.     if (get_bits1(gb)) {
  980.         s->weight_log2denom = svq3_get_ue_golomb(gb);
  981.         s->weight[0] = dirac_get_se_golomb(gb);
  982.         if (s->num_refs == 2)
  983.             s->weight[1] = dirac_get_se_golomb(gb);
  984.     }
  985.     return 0;
  986. }
  987.  
  988. /**
  989.  * Dirac Specification ->
  990.  * 11.3 Wavelet transform data. wavelet_transform()
  991.  */
  992. static int dirac_unpack_idwt_params(DiracContext *s)
  993. {
  994.     GetBitContext *gb = &s->gb;
  995.     int i, level;
  996.     unsigned tmp;
  997.  
  998. #define CHECKEDREAD(dst, cond, errmsg) \
  999.     tmp = svq3_get_ue_golomb(gb); \
  1000.     if (cond) { \
  1001.         av_log(s->avctx, AV_LOG_ERROR, errmsg); \
  1002.         return AVERROR_INVALIDDATA; \
  1003.     }\
  1004.     dst = tmp;
  1005.  
  1006.     align_get_bits(gb);
  1007.  
  1008.     s->zero_res = s->num_refs ? get_bits1(gb) : 0;
  1009.     if (s->zero_res)
  1010.         return 0;
  1011.  
  1012.     /*[DIRAC_STD] 11.3.1 Transform parameters. transform_parameters() */
  1013.     CHECKEDREAD(s->wavelet_idx, tmp > 6, "wavelet_idx is too big\n")
  1014.  
  1015.     CHECKEDREAD(s->wavelet_depth, tmp > MAX_DWT_LEVELS || tmp < 1, "invalid number of DWT decompositions\n")
  1016.  
  1017.     if (!s->low_delay) {
  1018.         /* Codeblock parameters (core syntax only) */
  1019.         if (get_bits1(gb)) {
  1020.             for (i = 0; i <= s->wavelet_depth; i++) {
  1021.                 CHECKEDREAD(s->codeblock[i].width , tmp < 1 || tmp > (s->avctx->width >>s->wavelet_depth-i), "codeblock width invalid\n")
  1022.                 CHECKEDREAD(s->codeblock[i].height, tmp < 1 || tmp > (s->avctx->height>>s->wavelet_depth-i), "codeblock height invalid\n")
  1023.             }
  1024.  
  1025.             CHECKEDREAD(s->codeblock_mode, tmp > 1, "unknown codeblock mode\n")
  1026.         } else
  1027.             for (i = 0; i <= s->wavelet_depth; i++)
  1028.                 s->codeblock[i].width = s->codeblock[i].height = 1;
  1029.     } else {
  1030.         /* Slice parameters + quantization matrix*/
  1031.         /*[DIRAC_STD] 11.3.4 Slice coding Parameters (low delay syntax only). slice_parameters() */
  1032.         s->lowdelay.num_x     = svq3_get_ue_golomb(gb);
  1033.         s->lowdelay.num_y     = svq3_get_ue_golomb(gb);
  1034.         s->lowdelay.bytes.num = svq3_get_ue_golomb(gb);
  1035.         s->lowdelay.bytes.den = svq3_get_ue_golomb(gb);
  1036.  
  1037.         if (s->lowdelay.bytes.den <= 0) {
  1038.             av_log(s->avctx,AV_LOG_ERROR,"Invalid lowdelay.bytes.den\n");
  1039.             return AVERROR_INVALIDDATA;
  1040.         }
  1041.  
  1042.         /* [DIRAC_STD] 11.3.5 Quantisation matrices (low-delay syntax). quant_matrix() */
  1043.         if (get_bits1(gb)) {
  1044.             av_log(s->avctx,AV_LOG_DEBUG,"Low Delay: Has Custom Quantization Matrix!\n");
  1045.             /* custom quantization matrix */
  1046.             s->lowdelay.quant[0][0] = svq3_get_ue_golomb(gb);
  1047.             for (level = 0; level < s->wavelet_depth; level++) {
  1048.                 s->lowdelay.quant[level][1] = svq3_get_ue_golomb(gb);
  1049.                 s->lowdelay.quant[level][2] = svq3_get_ue_golomb(gb);
  1050.                 s->lowdelay.quant[level][3] = svq3_get_ue_golomb(gb);
  1051.             }
  1052.         } else {
  1053.             if (s->wavelet_depth > 4) {
  1054.                 av_log(s->avctx,AV_LOG_ERROR,"Mandatory custom low delay matrix missing for depth %d\n", s->wavelet_depth);
  1055.                 return AVERROR_INVALIDDATA;
  1056.             }
  1057.             /* default quantization matrix */
  1058.             for (level = 0; level < s->wavelet_depth; level++)
  1059.                 for (i = 0; i < 4; i++) {
  1060.                     s->lowdelay.quant[level][i] = default_qmat[s->wavelet_idx][level][i];
  1061.                     /* haar with no shift differs for different depths */
  1062.                     if (s->wavelet_idx == 3)
  1063.                         s->lowdelay.quant[level][i] += 4*(s->wavelet_depth-1 - level);
  1064.                 }
  1065.         }
  1066.     }
  1067.     return 0;
  1068. }
  1069.  
  1070. static inline int pred_sbsplit(uint8_t *sbsplit, int stride, int x, int y)
  1071. {
  1072.     static const uint8_t avgsplit[7] = { 0, 0, 1, 1, 1, 2, 2 };
  1073.  
  1074.     if (!(x|y))
  1075.         return 0;
  1076.     else if (!y)
  1077.         return sbsplit[-1];
  1078.     else if (!x)
  1079.         return sbsplit[-stride];
  1080.  
  1081.     return avgsplit[sbsplit[-1] + sbsplit[-stride] + sbsplit[-stride-1]];
  1082. }
  1083.  
  1084. static inline int pred_block_mode(DiracBlock *block, int stride, int x, int y, int refmask)
  1085. {
  1086.     int pred;
  1087.  
  1088.     if (!(x|y))
  1089.         return 0;
  1090.     else if (!y)
  1091.         return block[-1].ref & refmask;
  1092.     else if (!x)
  1093.         return block[-stride].ref & refmask;
  1094.  
  1095.     /* return the majority */
  1096.     pred = (block[-1].ref & refmask) + (block[-stride].ref & refmask) + (block[-stride-1].ref & refmask);
  1097.     return (pred >> 1) & refmask;
  1098. }
  1099.  
  1100. static inline void pred_block_dc(DiracBlock *block, int stride, int x, int y)
  1101. {
  1102.     int i, n = 0;
  1103.  
  1104.     memset(block->u.dc, 0, sizeof(block->u.dc));
  1105.  
  1106.     if (x && !(block[-1].ref & 3)) {
  1107.         for (i = 0; i < 3; i++)
  1108.             block->u.dc[i] += block[-1].u.dc[i];
  1109.         n++;
  1110.     }
  1111.  
  1112.     if (y && !(block[-stride].ref & 3)) {
  1113.         for (i = 0; i < 3; i++)
  1114.             block->u.dc[i] += block[-stride].u.dc[i];
  1115.         n++;
  1116.     }
  1117.  
  1118.     if (x && y && !(block[-1-stride].ref & 3)) {
  1119.         for (i = 0; i < 3; i++)
  1120.             block->u.dc[i] += block[-1-stride].u.dc[i];
  1121.         n++;
  1122.     }
  1123.  
  1124.     if (n == 2) {
  1125.         for (i = 0; i < 3; i++)
  1126.             block->u.dc[i] = (block->u.dc[i]+1)>>1;
  1127.     } else if (n == 3) {
  1128.         for (i = 0; i < 3; i++)
  1129.             block->u.dc[i] = divide3(block->u.dc[i]);
  1130.     }
  1131. }
  1132.  
  1133. static inline void pred_mv(DiracBlock *block, int stride, int x, int y, int ref)
  1134. {
  1135.     int16_t *pred[3];
  1136.     int refmask = ref+1;
  1137.     int mask = refmask | DIRAC_REF_MASK_GLOBAL; /*  exclude gmc blocks */
  1138.     int n = 0;
  1139.  
  1140.     if (x && (block[-1].ref & mask) == refmask)
  1141.         pred[n++] = block[-1].u.mv[ref];
  1142.  
  1143.     if (y && (block[-stride].ref & mask) == refmask)
  1144.         pred[n++] = block[-stride].u.mv[ref];
  1145.  
  1146.     if (x && y && (block[-stride-1].ref & mask) == refmask)
  1147.         pred[n++] = block[-stride-1].u.mv[ref];
  1148.  
  1149.     switch (n) {
  1150.     case 0:
  1151.         block->u.mv[ref][0] = 0;
  1152.         block->u.mv[ref][1] = 0;
  1153.         break;
  1154.     case 1:
  1155.         block->u.mv[ref][0] = pred[0][0];
  1156.         block->u.mv[ref][1] = pred[0][1];
  1157.         break;
  1158.     case 2:
  1159.         block->u.mv[ref][0] = (pred[0][0] + pred[1][0] + 1) >> 1;
  1160.         block->u.mv[ref][1] = (pred[0][1] + pred[1][1] + 1) >> 1;
  1161.         break;
  1162.     case 3:
  1163.         block->u.mv[ref][0] = mid_pred(pred[0][0], pred[1][0], pred[2][0]);
  1164.         block->u.mv[ref][1] = mid_pred(pred[0][1], pred[1][1], pred[2][1]);
  1165.         break;
  1166.     }
  1167. }
  1168.  
  1169. static void global_mv(DiracContext *s, DiracBlock *block, int x, int y, int ref)
  1170. {
  1171.     int ez      = s->globalmc[ref].zrs_exp;
  1172.     int ep      = s->globalmc[ref].perspective_exp;
  1173.     int (*A)[2] = s->globalmc[ref].zrs;
  1174.     int *b      = s->globalmc[ref].pan_tilt;
  1175.     int *c      = s->globalmc[ref].perspective;
  1176.  
  1177.     int m       = (1<<ep) - (c[0]*x + c[1]*y);
  1178.     int mx      = m * ((A[0][0] * x + A[0][1]*y) + (1<<ez) * b[0]);
  1179.     int my      = m * ((A[1][0] * x + A[1][1]*y) + (1<<ez) * b[1]);
  1180.  
  1181.     block->u.mv[ref][0] = (mx + (1<<(ez+ep))) >> (ez+ep);
  1182.     block->u.mv[ref][1] = (my + (1<<(ez+ep))) >> (ez+ep);
  1183. }
  1184.  
  1185. static void decode_block_params(DiracContext *s, DiracArith arith[8], DiracBlock *block,
  1186.                                 int stride, int x, int y)
  1187. {
  1188.     int i;
  1189.  
  1190.     block->ref  = pred_block_mode(block, stride, x, y, DIRAC_REF_MASK_REF1);
  1191.     block->ref ^= dirac_get_arith_bit(arith, CTX_PMODE_REF1);
  1192.  
  1193.     if (s->num_refs == 2) {
  1194.         block->ref |= pred_block_mode(block, stride, x, y, DIRAC_REF_MASK_REF2);
  1195.         block->ref ^= dirac_get_arith_bit(arith, CTX_PMODE_REF2) << 1;
  1196.     }
  1197.  
  1198.     if (!block->ref) {
  1199.         pred_block_dc(block, stride, x, y);
  1200.         for (i = 0; i < 3; i++)
  1201.             block->u.dc[i] += dirac_get_arith_int(arith+1+i, CTX_DC_F1, CTX_DC_DATA);
  1202.         return;
  1203.     }
  1204.  
  1205.     if (s->globalmc_flag) {
  1206.         block->ref |= pred_block_mode(block, stride, x, y, DIRAC_REF_MASK_GLOBAL);
  1207.         block->ref ^= dirac_get_arith_bit(arith, CTX_GLOBAL_BLOCK) << 2;
  1208.     }
  1209.  
  1210.     for (i = 0; i < s->num_refs; i++)
  1211.         if (block->ref & (i+1)) {
  1212.             if (block->ref & DIRAC_REF_MASK_GLOBAL) {
  1213.                 global_mv(s, block, x, y, i);
  1214.             } else {
  1215.                 pred_mv(block, stride, x, y, i);
  1216.                 block->u.mv[i][0] += dirac_get_arith_int(arith + 4 + 2 * i, CTX_MV_F1, CTX_MV_DATA);
  1217.                 block->u.mv[i][1] += dirac_get_arith_int(arith + 5 + 2 * i, CTX_MV_F1, CTX_MV_DATA);
  1218.             }
  1219.         }
  1220. }
  1221.  
  1222. /**
  1223.  * Copies the current block to the other blocks covered by the current superblock split mode
  1224.  */
  1225. static void propagate_block_data(DiracBlock *block, int stride, int size)
  1226. {
  1227.     int x, y;
  1228.     DiracBlock *dst = block;
  1229.  
  1230.     for (x = 1; x < size; x++)
  1231.         dst[x] = *block;
  1232.  
  1233.     for (y = 1; y < size; y++) {
  1234.         dst += stride;
  1235.         for (x = 0; x < size; x++)
  1236.             dst[x] = *block;
  1237.     }
  1238. }
  1239.  
  1240. /**
  1241.  * Dirac Specification ->
  1242.  * 12. Block motion data syntax
  1243.  */
  1244. static int dirac_unpack_block_motion_data(DiracContext *s)
  1245. {
  1246.     GetBitContext *gb = &s->gb;
  1247.     uint8_t *sbsplit = s->sbsplit;
  1248.     int i, x, y, q, p;
  1249.     DiracArith arith[8];
  1250.  
  1251.     align_get_bits(gb);
  1252.  
  1253.     /* [DIRAC_STD] 11.2.4 and 12.2.1 Number of blocks and superblocks */
  1254.     s->sbwidth  = DIVRNDUP(s->source.width,  4*s->plane[0].xbsep);
  1255.     s->sbheight = DIVRNDUP(s->source.height, 4*s->plane[0].ybsep);
  1256.     s->blwidth  = 4 * s->sbwidth;
  1257.     s->blheight = 4 * s->sbheight;
  1258.  
  1259.     /* [DIRAC_STD] 12.3.1 Superblock splitting modes. superblock_split_modes()
  1260.        decode superblock split modes */
  1261.     ff_dirac_init_arith_decoder(arith, gb, svq3_get_ue_golomb(gb));     /* svq3_get_ue_golomb(gb) is the length */
  1262.     for (y = 0; y < s->sbheight; y++) {
  1263.         for (x = 0; x < s->sbwidth; x++) {
  1264.             unsigned int split  = dirac_get_arith_uint(arith, CTX_SB_F1, CTX_SB_DATA);
  1265.             if (split > 2)
  1266.                 return AVERROR_INVALIDDATA;
  1267.             sbsplit[x] = (split + pred_sbsplit(sbsplit+x, s->sbwidth, x, y)) % 3;
  1268.         }
  1269.         sbsplit += s->sbwidth;
  1270.     }
  1271.  
  1272.     /* setup arith decoding */
  1273.     ff_dirac_init_arith_decoder(arith, gb, svq3_get_ue_golomb(gb));
  1274.     for (i = 0; i < s->num_refs; i++) {
  1275.         ff_dirac_init_arith_decoder(arith + 4 + 2 * i, gb, svq3_get_ue_golomb(gb));
  1276.         ff_dirac_init_arith_decoder(arith + 5 + 2 * i, gb, svq3_get_ue_golomb(gb));
  1277.     }
  1278.     for (i = 0; i < 3; i++)
  1279.         ff_dirac_init_arith_decoder(arith+1+i, gb, svq3_get_ue_golomb(gb));
  1280.  
  1281.     for (y = 0; y < s->sbheight; y++)
  1282.         for (x = 0; x < s->sbwidth; x++) {
  1283.             int blkcnt = 1 << s->sbsplit[y * s->sbwidth + x];
  1284.             int step   = 4 >> s->sbsplit[y * s->sbwidth + x];
  1285.  
  1286.             for (q = 0; q < blkcnt; q++)
  1287.                 for (p = 0; p < blkcnt; p++) {
  1288.                     int bx = 4 * x + p*step;
  1289.                     int by = 4 * y + q*step;
  1290.                     DiracBlock *block = &s->blmotion[by*s->blwidth + bx];
  1291.                     decode_block_params(s, arith, block, s->blwidth, bx, by);
  1292.                     propagate_block_data(block, s->blwidth, step);
  1293.                 }
  1294.         }
  1295.  
  1296.     return 0;
  1297. }
  1298.  
  1299. static int weight(int i, int blen, int offset)
  1300. {
  1301. #define ROLLOFF(i) offset == 1 ? ((i) ? 5 : 3) :        \
  1302.     (1 + (6*(i) + offset - 1) / (2*offset - 1))
  1303.  
  1304.     if (i < 2*offset)
  1305.         return ROLLOFF(i);
  1306.     else if (i > blen-1 - 2*offset)
  1307.         return ROLLOFF(blen-1 - i);
  1308.     return 8;
  1309. }
  1310.  
  1311. static void init_obmc_weight_row(Plane *p, uint8_t *obmc_weight, int stride,
  1312.                                  int left, int right, int wy)
  1313. {
  1314.     int x;
  1315.     for (x = 0; left && x < p->xblen >> 1; x++)
  1316.         obmc_weight[x] = wy*8;
  1317.     for (; x < p->xblen >> right; x++)
  1318.         obmc_weight[x] = wy*weight(x, p->xblen, p->xoffset);
  1319.     for (; x < p->xblen; x++)
  1320.         obmc_weight[x] = wy*8;
  1321.     for (; x < stride; x++)
  1322.         obmc_weight[x] = 0;
  1323. }
  1324.  
  1325. static void init_obmc_weight(Plane *p, uint8_t *obmc_weight, int stride,
  1326.                              int left, int right, int top, int bottom)
  1327. {
  1328.     int y;
  1329.     for (y = 0; top && y < p->yblen >> 1; y++) {
  1330.         init_obmc_weight_row(p, obmc_weight, stride, left, right, 8);
  1331.         obmc_weight += stride;
  1332.     }
  1333.     for (; y < p->yblen >> bottom; y++) {
  1334.         int wy = weight(y, p->yblen, p->yoffset);
  1335.         init_obmc_weight_row(p, obmc_weight, stride, left, right, wy);
  1336.         obmc_weight += stride;
  1337.     }
  1338.     for (; y < p->yblen; y++) {
  1339.         init_obmc_weight_row(p, obmc_weight, stride, left, right, 8);
  1340.         obmc_weight += stride;
  1341.     }
  1342. }
  1343.  
  1344. static void init_obmc_weights(DiracContext *s, Plane *p, int by)
  1345. {
  1346.     int top = !by;
  1347.     int bottom = by == s->blheight-1;
  1348.  
  1349.     /* don't bother re-initing for rows 2 to blheight-2, the weights don't change */
  1350.     if (top || bottom || by == 1) {
  1351.         init_obmc_weight(p, s->obmc_weight[0], MAX_BLOCKSIZE, 1, 0, top, bottom);
  1352.         init_obmc_weight(p, s->obmc_weight[1], MAX_BLOCKSIZE, 0, 0, top, bottom);
  1353.         init_obmc_weight(p, s->obmc_weight[2], MAX_BLOCKSIZE, 0, 1, top, bottom);
  1354.     }
  1355. }
  1356.  
  1357. static const uint8_t epel_weights[4][4][4] = {
  1358.     {{ 16,  0,  0,  0 },
  1359.      { 12,  4,  0,  0 },
  1360.      {  8,  8,  0,  0 },
  1361.      {  4, 12,  0,  0 }},
  1362.     {{ 12,  0,  4,  0 },
  1363.      {  9,  3,  3,  1 },
  1364.      {  6,  6,  2,  2 },
  1365.      {  3,  9,  1,  3 }},
  1366.     {{  8,  0,  8,  0 },
  1367.      {  6,  2,  6,  2 },
  1368.      {  4,  4,  4,  4 },
  1369.      {  2,  6,  2,  6 }},
  1370.     {{  4,  0, 12,  0 },
  1371.      {  3,  1,  9,  3 },
  1372.      {  2,  2,  6,  6 },
  1373.      {  1,  3,  3,  9 }}
  1374. };
  1375.  
  1376. /**
  1377.  * For block x,y, determine which of the hpel planes to do bilinear
  1378.  * interpolation from and set src[] to the location in each hpel plane
  1379.  * to MC from.
  1380.  *
  1381.  * @return the index of the put_dirac_pixels_tab function to use
  1382.  *  0 for 1 plane (fpel,hpel), 1 for 2 planes (qpel), 2 for 4 planes (qpel), and 3 for epel
  1383.  */
  1384. static int mc_subpel(DiracContext *s, DiracBlock *block, const uint8_t *src[5],
  1385.                      int x, int y, int ref, int plane)
  1386. {
  1387.     Plane *p = &s->plane[plane];
  1388.     uint8_t **ref_hpel = s->ref_pics[ref]->hpel[plane];
  1389.     int motion_x = block->u.mv[ref][0];
  1390.     int motion_y = block->u.mv[ref][1];
  1391.     int mx, my, i, epel, nplanes = 0;
  1392.  
  1393.     if (plane) {
  1394.         motion_x >>= s->chroma_x_shift;
  1395.         motion_y >>= s->chroma_y_shift;
  1396.     }
  1397.  
  1398.     mx         = motion_x & ~(-1U << s->mv_precision);
  1399.     my         = motion_y & ~(-1U << s->mv_precision);
  1400.     motion_x >>= s->mv_precision;
  1401.     motion_y >>= s->mv_precision;
  1402.     /* normalize subpel coordinates to epel */
  1403.     /* TODO: template this function? */
  1404.     mx      <<= 3 - s->mv_precision;
  1405.     my      <<= 3 - s->mv_precision;
  1406.  
  1407.     x += motion_x;
  1408.     y += motion_y;
  1409.     epel = (mx|my)&1;
  1410.  
  1411.     /* hpel position */
  1412.     if (!((mx|my)&3)) {
  1413.         nplanes = 1;
  1414.         src[0] = ref_hpel[(my>>1)+(mx>>2)] + y*p->stride + x;
  1415.     } else {
  1416.         /* qpel or epel */
  1417.         nplanes = 4;
  1418.         for (i = 0; i < 4; i++)
  1419.             src[i] = ref_hpel[i] + y*p->stride + x;
  1420.  
  1421.         /* if we're interpolating in the right/bottom halves, adjust the planes as needed
  1422.            we increment x/y because the edge changes for half of the pixels */
  1423.         if (mx > 4) {
  1424.             src[0] += 1;
  1425.             src[2] += 1;
  1426.             x++;
  1427.         }
  1428.         if (my > 4) {
  1429.             src[0] += p->stride;
  1430.             src[1] += p->stride;
  1431.             y++;
  1432.         }
  1433.  
  1434.         /* hpel planes are:
  1435.            [0]: F  [1]: H
  1436.            [2]: V  [3]: C */
  1437.         if (!epel) {
  1438.             /* check if we really only need 2 planes since either mx or my is
  1439.                a hpel position. (epel weights of 0 handle this there) */
  1440.             if (!(mx&3)) {
  1441.                 /* mx == 0: average [0] and [2]
  1442.                    mx == 4: average [1] and [3] */
  1443.                 src[!mx] = src[2 + !!mx];
  1444.                 nplanes = 2;
  1445.             } else if (!(my&3)) {
  1446.                 src[0] = src[(my>>1)  ];
  1447.                 src[1] = src[(my>>1)+1];
  1448.                 nplanes = 2;
  1449.             }
  1450.         } else {
  1451.             /* adjust the ordering if needed so the weights work */
  1452.             if (mx > 4) {
  1453.                 FFSWAP(const uint8_t *, src[0], src[1]);
  1454.                 FFSWAP(const uint8_t *, src[2], src[3]);
  1455.             }
  1456.             if (my > 4) {
  1457.                 FFSWAP(const uint8_t *, src[0], src[2]);
  1458.                 FFSWAP(const uint8_t *, src[1], src[3]);
  1459.             }
  1460.             src[4] = epel_weights[my&3][mx&3];
  1461.         }
  1462.     }
  1463.  
  1464.     /* fixme: v/h _edge_pos */
  1465.     if (x + p->xblen > p->width +EDGE_WIDTH/2 ||
  1466.         y + p->yblen > p->height+EDGE_WIDTH/2 ||
  1467.         x < 0 || y < 0) {
  1468.         for (i = 0; i < nplanes; i++) {
  1469.             s->vdsp.emulated_edge_mc(s->edge_emu_buffer[i], src[i],
  1470.                                      p->stride, p->stride,
  1471.                                      p->xblen, p->yblen, x, y,
  1472.                                      p->width+EDGE_WIDTH/2, p->height+EDGE_WIDTH/2);
  1473.             src[i] = s->edge_emu_buffer[i];
  1474.         }
  1475.     }
  1476.     return (nplanes>>1) + epel;
  1477. }
  1478.  
  1479. static void add_dc(uint16_t *dst, int dc, int stride,
  1480.                    uint8_t *obmc_weight, int xblen, int yblen)
  1481. {
  1482.     int x, y;
  1483.     dc += 128;
  1484.  
  1485.     for (y = 0; y < yblen; y++) {
  1486.         for (x = 0; x < xblen; x += 2) {
  1487.             dst[x  ] += dc * obmc_weight[x  ];
  1488.             dst[x+1] += dc * obmc_weight[x+1];
  1489.         }
  1490.         dst          += stride;
  1491.         obmc_weight  += MAX_BLOCKSIZE;
  1492.     }
  1493. }
  1494.  
  1495. static void block_mc(DiracContext *s, DiracBlock *block,
  1496.                      uint16_t *mctmp, uint8_t *obmc_weight,
  1497.                      int plane, int dstx, int dsty)
  1498. {
  1499.     Plane *p = &s->plane[plane];
  1500.     const uint8_t *src[5];
  1501.     int idx;
  1502.  
  1503.     switch (block->ref&3) {
  1504.     case 0: /* DC */
  1505.         add_dc(mctmp, block->u.dc[plane], p->stride, obmc_weight, p->xblen, p->yblen);
  1506.         return;
  1507.     case 1:
  1508.     case 2:
  1509.         idx = mc_subpel(s, block, src, dstx, dsty, (block->ref&3)-1, plane);
  1510.         s->put_pixels_tab[idx](s->mcscratch, src, p->stride, p->yblen);
  1511.         if (s->weight_func)
  1512.             s->weight_func(s->mcscratch, p->stride, s->weight_log2denom,
  1513.                            s->weight[0] + s->weight[1], p->yblen);
  1514.         break;
  1515.     case 3:
  1516.         idx = mc_subpel(s, block, src, dstx, dsty, 0, plane);
  1517.         s->put_pixels_tab[idx](s->mcscratch, src, p->stride, p->yblen);
  1518.         idx = mc_subpel(s, block, src, dstx, dsty, 1, plane);
  1519.         if (s->biweight_func) {
  1520.             /* fixme: +32 is a quick hack */
  1521.             s->put_pixels_tab[idx](s->mcscratch + 32, src, p->stride, p->yblen);
  1522.             s->biweight_func(s->mcscratch, s->mcscratch+32, p->stride, s->weight_log2denom,
  1523.                              s->weight[0], s->weight[1], p->yblen);
  1524.         } else
  1525.             s->avg_pixels_tab[idx](s->mcscratch, src, p->stride, p->yblen);
  1526.         break;
  1527.     }
  1528.     s->add_obmc(mctmp, s->mcscratch, p->stride, obmc_weight, p->yblen);
  1529. }
  1530.  
  1531. static void mc_row(DiracContext *s, DiracBlock *block, uint16_t *mctmp, int plane, int dsty)
  1532. {
  1533.     Plane *p = &s->plane[plane];
  1534.     int x, dstx = p->xbsep - p->xoffset;
  1535.  
  1536.     block_mc(s, block, mctmp, s->obmc_weight[0], plane, -p->xoffset, dsty);
  1537.     mctmp += p->xbsep;
  1538.  
  1539.     for (x = 1; x < s->blwidth-1; x++) {
  1540.         block_mc(s, block+x, mctmp, s->obmc_weight[1], plane, dstx, dsty);
  1541.         dstx  += p->xbsep;
  1542.         mctmp += p->xbsep;
  1543.     }
  1544.     block_mc(s, block+x, mctmp, s->obmc_weight[2], plane, dstx, dsty);
  1545. }
  1546.  
  1547. static void select_dsp_funcs(DiracContext *s, int width, int height, int xblen, int yblen)
  1548. {
  1549.     int idx = 0;
  1550.     if (xblen > 8)
  1551.         idx = 1;
  1552.     if (xblen > 16)
  1553.         idx = 2;
  1554.  
  1555.     memcpy(s->put_pixels_tab, s->diracdsp.put_dirac_pixels_tab[idx], sizeof(s->put_pixels_tab));
  1556.     memcpy(s->avg_pixels_tab, s->diracdsp.avg_dirac_pixels_tab[idx], sizeof(s->avg_pixels_tab));
  1557.     s->add_obmc = s->diracdsp.add_dirac_obmc[idx];
  1558.     if (s->weight_log2denom > 1 || s->weight[0] != 1 || s->weight[1] != 1) {
  1559.         s->weight_func   = s->diracdsp.weight_dirac_pixels_tab[idx];
  1560.         s->biweight_func = s->diracdsp.biweight_dirac_pixels_tab[idx];
  1561.     } else {
  1562.         s->weight_func   = NULL;
  1563.         s->biweight_func = NULL;
  1564.     }
  1565. }
  1566.  
  1567. static int interpolate_refplane(DiracContext *s, DiracFrame *ref, int plane, int width, int height)
  1568. {
  1569.     /* chroma allocates an edge of 8 when subsampled
  1570.        which for 4:2:2 means an h edge of 16 and v edge of 8
  1571.        just use 8 for everything for the moment */
  1572.     int i, edge = EDGE_WIDTH/2;
  1573.  
  1574.     ref->hpel[plane][0] = ref->avframe->data[plane];
  1575.     s->mpvencdsp.draw_edges(ref->hpel[plane][0], ref->avframe->linesize[plane], width, height, edge, edge, EDGE_TOP | EDGE_BOTTOM); /* EDGE_TOP | EDGE_BOTTOM values just copied to make it build, this needs to be ensured */
  1576.  
  1577.     /* no need for hpel if we only have fpel vectors */
  1578.     if (!s->mv_precision)
  1579.         return 0;
  1580.  
  1581.     for (i = 1; i < 4; i++) {
  1582.         if (!ref->hpel_base[plane][i])
  1583.             ref->hpel_base[plane][i] = av_malloc((height+2*edge) * ref->avframe->linesize[plane] + 32);
  1584.         if (!ref->hpel_base[plane][i]) {
  1585.             return AVERROR(ENOMEM);
  1586.         }
  1587.         /* we need to be 16-byte aligned even for chroma */
  1588.         ref->hpel[plane][i] = ref->hpel_base[plane][i] + edge*ref->avframe->linesize[plane] + 16;
  1589.     }
  1590.  
  1591.     if (!ref->interpolated[plane]) {
  1592.         s->diracdsp.dirac_hpel_filter(ref->hpel[plane][1], ref->hpel[plane][2],
  1593.                                       ref->hpel[plane][3], ref->hpel[plane][0],
  1594.                                       ref->avframe->linesize[plane], width, height);
  1595.         s->mpvencdsp.draw_edges(ref->hpel[plane][1], ref->avframe->linesize[plane], width, height, edge, edge, EDGE_TOP | EDGE_BOTTOM);
  1596.         s->mpvencdsp.draw_edges(ref->hpel[plane][2], ref->avframe->linesize[plane], width, height, edge, edge, EDGE_TOP | EDGE_BOTTOM);
  1597.         s->mpvencdsp.draw_edges(ref->hpel[plane][3], ref->avframe->linesize[plane], width, height, edge, edge, EDGE_TOP | EDGE_BOTTOM);
  1598.     }
  1599.     ref->interpolated[plane] = 1;
  1600.  
  1601.     return 0;
  1602. }
  1603.  
  1604. /**
  1605.  * Dirac Specification ->
  1606.  * 13.0 Transform data syntax. transform_data()
  1607.  */
  1608. static int dirac_decode_frame_internal(DiracContext *s)
  1609. {
  1610.     DWTContext d;
  1611.     int y, i, comp, dsty;
  1612.     int ret;
  1613.  
  1614.     if (s->low_delay) {
  1615.         /* [DIRAC_STD] 13.5.1 low_delay_transform_data() */
  1616.         for (comp = 0; comp < 3; comp++) {
  1617.             Plane *p = &s->plane[comp];
  1618.             memset(p->idwt_buf, 0, p->idwt_stride * p->idwt_height * sizeof(IDWTELEM));
  1619.         }
  1620.         if (!s->zero_res) {
  1621.             if ((ret = decode_lowdelay(s)) < 0)
  1622.                 return ret;
  1623.         }
  1624.     }
  1625.  
  1626.     for (comp = 0; comp < 3; comp++) {
  1627.         Plane *p       = &s->plane[comp];
  1628.         uint8_t *frame = s->current_picture->avframe->data[comp];
  1629.  
  1630.         /* FIXME: small resolutions */
  1631.         for (i = 0; i < 4; i++)
  1632.             s->edge_emu_buffer[i] = s->edge_emu_buffer_base + i*FFALIGN(p->width, 16);
  1633.  
  1634.         if (!s->zero_res && !s->low_delay)
  1635.         {
  1636.             memset(p->idwt_buf, 0, p->idwt_stride * p->idwt_height * sizeof(IDWTELEM));
  1637.             decode_component(s, comp); /* [DIRAC_STD] 13.4.1 core_transform_data() */
  1638.         }
  1639.         ret = ff_spatial_idwt_init2(&d, p->idwt_buf, p->idwt_width, p->idwt_height, p->idwt_stride,
  1640.                                     s->wavelet_idx+2, s->wavelet_depth, p->idwt_tmp);
  1641.         if (ret < 0)
  1642.             return ret;
  1643.  
  1644.         if (!s->num_refs) { /* intra */
  1645.             for (y = 0; y < p->height; y += 16) {
  1646.                 ff_spatial_idwt_slice2(&d, y+16); /* decode */
  1647.                 s->diracdsp.put_signed_rect_clamped(frame + y*p->stride, p->stride,
  1648.                                                     p->idwt_buf + y*p->idwt_stride, p->idwt_stride, p->width, 16);
  1649.             }
  1650.         } else { /* inter */
  1651.             int rowheight = p->ybsep*p->stride;
  1652.  
  1653.             select_dsp_funcs(s, p->width, p->height, p->xblen, p->yblen);
  1654.  
  1655.             for (i = 0; i < s->num_refs; i++) {
  1656.                 int ret = interpolate_refplane(s, s->ref_pics[i], comp, p->width, p->height);
  1657.                 if (ret < 0)
  1658.                     return ret;
  1659.             }
  1660.  
  1661.             memset(s->mctmp, 0, 4*p->yoffset*p->stride);
  1662.  
  1663.             dsty = -p->yoffset;
  1664.             for (y = 0; y < s->blheight; y++) {
  1665.                 int h     = 0,
  1666.                     start = FFMAX(dsty, 0);
  1667.                 uint16_t *mctmp    = s->mctmp + y*rowheight;
  1668.                 DiracBlock *blocks = s->blmotion + y*s->blwidth;
  1669.  
  1670.                 init_obmc_weights(s, p, y);
  1671.  
  1672.                 if (y == s->blheight-1 || start+p->ybsep > p->height)
  1673.                     h = p->height - start;
  1674.                 else
  1675.                     h = p->ybsep - (start - dsty);
  1676.                 if (h < 0)
  1677.                     break;
  1678.  
  1679.                 memset(mctmp+2*p->yoffset*p->stride, 0, 2*rowheight);
  1680.                 mc_row(s, blocks, mctmp, comp, dsty);
  1681.  
  1682.                 mctmp += (start - dsty)*p->stride + p->xoffset;
  1683.                 ff_spatial_idwt_slice2(&d, start + h); /* decode */
  1684.                 s->diracdsp.add_rect_clamped(frame + start*p->stride, mctmp, p->stride,
  1685.                                              p->idwt_buf + start*p->idwt_stride, p->idwt_stride, p->width, h);
  1686.  
  1687.                 dsty += p->ybsep;
  1688.             }
  1689.         }
  1690.     }
  1691.  
  1692.  
  1693.     return 0;
  1694. }
  1695.  
  1696. static int get_buffer_with_edge(AVCodecContext *avctx, AVFrame *f, int flags)
  1697. {
  1698.     int ret, i;
  1699.     int chroma_x_shift, chroma_y_shift;
  1700.     avcodec_get_chroma_sub_sample(avctx->pix_fmt, &chroma_x_shift, &chroma_y_shift);
  1701.  
  1702.     f->width  = avctx->width  + 2 * EDGE_WIDTH;
  1703.     f->height = avctx->height + 2 * EDGE_WIDTH + 2;
  1704.     ret = ff_get_buffer(avctx, f, flags);
  1705.     if (ret < 0)
  1706.         return ret;
  1707.  
  1708.     for (i = 0; f->data[i]; i++) {
  1709.         int offset = (EDGE_WIDTH >> (i && i<3 ? chroma_y_shift : 0)) *
  1710.                      f->linesize[i] + 32;
  1711.         f->data[i] += offset;
  1712.     }
  1713.     f->width  = avctx->width;
  1714.     f->height = avctx->height;
  1715.  
  1716.     return 0;
  1717. }
  1718.  
  1719. /**
  1720.  * Dirac Specification ->
  1721.  * 11.1.1 Picture Header. picture_header()
  1722.  */
  1723. static int dirac_decode_picture_header(DiracContext *s)
  1724. {
  1725.     unsigned retire, picnum;
  1726.     int i, j, ret;
  1727.     int64_t refdist, refnum;
  1728.     GetBitContext *gb = &s->gb;
  1729.  
  1730.     /* [DIRAC_STD] 11.1.1 Picture Header. picture_header() PICTURE_NUM */
  1731.     picnum = s->current_picture->avframe->display_picture_number = get_bits_long(gb, 32);
  1732.  
  1733.  
  1734.     av_log(s->avctx,AV_LOG_DEBUG,"PICTURE_NUM: %d\n",picnum);
  1735.  
  1736.     /* if this is the first keyframe after a sequence header, start our
  1737.        reordering from here */
  1738.     if (s->frame_number < 0)
  1739.         s->frame_number = picnum;
  1740.  
  1741.     s->ref_pics[0] = s->ref_pics[1] = NULL;
  1742.     for (i = 0; i < s->num_refs; i++) {
  1743.         refnum = (picnum + dirac_get_se_golomb(gb)) & 0xFFFFFFFF;
  1744.         refdist = INT64_MAX;
  1745.  
  1746.         /* find the closest reference to the one we want */
  1747.         /* Jordi: this is needed if the referenced picture hasn't yet arrived */
  1748.         for (j = 0; j < MAX_REFERENCE_FRAMES && refdist; j++)
  1749.             if (s->ref_frames[j]
  1750.                 && FFABS(s->ref_frames[j]->avframe->display_picture_number - refnum) < refdist) {
  1751.                 s->ref_pics[i] = s->ref_frames[j];
  1752.                 refdist = FFABS(s->ref_frames[j]->avframe->display_picture_number - refnum);
  1753.             }
  1754.  
  1755.         if (!s->ref_pics[i] || refdist)
  1756.             av_log(s->avctx, AV_LOG_DEBUG, "Reference not found\n");
  1757.  
  1758.         /* if there were no references at all, allocate one */
  1759.         if (!s->ref_pics[i])
  1760.             for (j = 0; j < MAX_FRAMES; j++)
  1761.                 if (!s->all_frames[j].avframe->data[0]) {
  1762.                     s->ref_pics[i] = &s->all_frames[j];
  1763.                     get_buffer_with_edge(s->avctx, s->ref_pics[i]->avframe, AV_GET_BUFFER_FLAG_REF);
  1764.                     break;
  1765.                 }
  1766.  
  1767.         if (!s->ref_pics[i]) {
  1768.             av_log(s->avctx, AV_LOG_ERROR, "Reference could not be allocated\n");
  1769.             return AVERROR_INVALIDDATA;
  1770.         }
  1771.  
  1772.     }
  1773.  
  1774.     /* retire the reference frames that are not used anymore */
  1775.     if (s->current_picture->reference) {
  1776.         retire = (picnum + dirac_get_se_golomb(gb)) & 0xFFFFFFFF;
  1777.         if (retire != picnum) {
  1778.             DiracFrame *retire_pic = remove_frame(s->ref_frames, retire);
  1779.  
  1780.             if (retire_pic)
  1781.                 retire_pic->reference &= DELAYED_PIC_REF;
  1782.             else
  1783.                 av_log(s->avctx, AV_LOG_DEBUG, "Frame to retire not found\n");
  1784.         }
  1785.  
  1786.         /* if reference array is full, remove the oldest as per the spec */
  1787.         while (add_frame(s->ref_frames, MAX_REFERENCE_FRAMES, s->current_picture)) {
  1788.             av_log(s->avctx, AV_LOG_ERROR, "Reference frame overflow\n");
  1789.             remove_frame(s->ref_frames, s->ref_frames[0]->avframe->display_picture_number)->reference &= DELAYED_PIC_REF;
  1790.         }
  1791.     }
  1792.  
  1793.     if (s->num_refs) {
  1794.         ret = dirac_unpack_prediction_parameters(s);  /* [DIRAC_STD] 11.2 Picture Prediction Data. picture_prediction() */
  1795.         if (ret < 0)
  1796.             return ret;
  1797.         ret = dirac_unpack_block_motion_data(s);      /* [DIRAC_STD] 12. Block motion data syntax                       */
  1798.         if (ret < 0)
  1799.             return ret;
  1800.     }
  1801.     ret = dirac_unpack_idwt_params(s);                /* [DIRAC_STD] 11.3 Wavelet transform data                        */
  1802.     if (ret < 0)
  1803.         return ret;
  1804.  
  1805.     init_planes(s);
  1806.     return 0;
  1807. }
  1808.  
  1809. static int get_delayed_pic(DiracContext *s, AVFrame *picture, int *got_frame)
  1810. {
  1811.     DiracFrame *out = s->delay_frames[0];
  1812.     int i, out_idx  = 0;
  1813.     int ret;
  1814.  
  1815.     /* find frame with lowest picture number */
  1816.     for (i = 1; s->delay_frames[i]; i++)
  1817.         if (s->delay_frames[i]->avframe->display_picture_number < out->avframe->display_picture_number) {
  1818.             out     = s->delay_frames[i];
  1819.             out_idx = i;
  1820.         }
  1821.  
  1822.     for (i = out_idx; s->delay_frames[i]; i++)
  1823.         s->delay_frames[i] = s->delay_frames[i+1];
  1824.  
  1825.     if (out) {
  1826.         out->reference ^= DELAYED_PIC_REF;
  1827.         *got_frame = 1;
  1828.         if((ret = av_frame_ref(picture, out->avframe)) < 0)
  1829.             return ret;
  1830.     }
  1831.  
  1832.     return 0;
  1833. }
  1834.  
  1835. /**
  1836.  * Dirac Specification ->
  1837.  * 9.6 Parse Info Header Syntax. parse_info()
  1838.  * 4 byte start code + byte parse code + 4 byte size + 4 byte previous size
  1839.  */
  1840. #define DATA_UNIT_HEADER_SIZE 13
  1841.  
  1842. /* [DIRAC_STD] dirac_decode_data_unit makes reference to the while defined in 9.3
  1843.    inside the function parse_sequence() */
  1844. static int dirac_decode_data_unit(AVCodecContext *avctx, const uint8_t *buf, int size)
  1845. {
  1846.     DiracContext *s   = avctx->priv_data;
  1847.     DiracFrame *pic   = NULL;
  1848.     int ret, i, parse_code;
  1849.     unsigned tmp;
  1850.  
  1851.     if (size < DATA_UNIT_HEADER_SIZE)
  1852.         return AVERROR_INVALIDDATA;
  1853.  
  1854.     parse_code = buf[4];
  1855.  
  1856.     init_get_bits(&s->gb, &buf[13], 8*(size - DATA_UNIT_HEADER_SIZE));
  1857.  
  1858.     if (parse_code == pc_seq_header) {
  1859.         if (s->seen_sequence_header)
  1860.             return 0;
  1861.  
  1862.         /* [DIRAC_STD] 10. Sequence header */
  1863.         ret = avpriv_dirac_parse_sequence_header(avctx, &s->gb, &s->source);
  1864.         if (ret < 0)
  1865.             return ret;
  1866.  
  1867.         avcodec_get_chroma_sub_sample(avctx->pix_fmt, &s->chroma_x_shift, &s->chroma_y_shift);
  1868.  
  1869.         ret = alloc_sequence_buffers(s);
  1870.         if (ret < 0)
  1871.             return ret;
  1872.  
  1873.         s->seen_sequence_header = 1;
  1874.     } else if (parse_code == pc_eos) { /* [DIRAC_STD] End of Sequence */
  1875.         free_sequence_buffers(s);
  1876.         s->seen_sequence_header = 0;
  1877.     } else if (parse_code == pc_aux_data) {
  1878.         if (buf[13] == 1) {     /* encoder implementation/version */
  1879.             int ver[3];
  1880.             /* versions older than 1.0.8 don't store quant delta for
  1881.                subbands with only one codeblock */
  1882.             if (sscanf(buf+14, "Schroedinger %d.%d.%d", ver, ver+1, ver+2) == 3)
  1883.                 if (ver[0] == 1 && ver[1] == 0 && ver[2] <= 7)
  1884.                     s->old_delta_quant = 1;
  1885.         }
  1886.     } else if (parse_code & 0x8) {  /* picture data unit */
  1887.         if (!s->seen_sequence_header) {
  1888.             av_log(avctx, AV_LOG_DEBUG, "Dropping frame without sequence header\n");
  1889.             return AVERROR_INVALIDDATA;
  1890.         }
  1891.  
  1892.         /* find an unused frame */
  1893.         for (i = 0; i < MAX_FRAMES; i++)
  1894.             if (s->all_frames[i].avframe->data[0] == NULL)
  1895.                 pic = &s->all_frames[i];
  1896.         if (!pic) {
  1897.             av_log(avctx, AV_LOG_ERROR, "framelist full\n");
  1898.             return AVERROR_INVALIDDATA;
  1899.         }
  1900.  
  1901.         av_frame_unref(pic->avframe);
  1902.  
  1903.         /* [DIRAC_STD] Defined in 9.6.1 ... */
  1904.         tmp            =  parse_code & 0x03;                   /* [DIRAC_STD] num_refs()      */
  1905.         if (tmp > 2) {
  1906.             av_log(avctx, AV_LOG_ERROR, "num_refs of 3\n");
  1907.             return AVERROR_INVALIDDATA;
  1908.         }
  1909.         s->num_refs    = tmp;
  1910.         s->is_arith    = (parse_code & 0x48) == 0x08;          /* [DIRAC_STD] using_ac()      */
  1911.         s->low_delay   = (parse_code & 0x88) == 0x88;          /* [DIRAC_STD] is_low_delay()  */
  1912.         pic->reference = (parse_code & 0x0C) == 0x0C;  /* [DIRAC_STD]  is_reference() */
  1913.         pic->avframe->key_frame = s->num_refs == 0;             /* [DIRAC_STD] is_intra()      */
  1914.         pic->avframe->pict_type = s->num_refs + 1;              /* Definition of AVPictureType in avutil.h */
  1915.  
  1916.         if ((ret = get_buffer_with_edge(avctx, pic->avframe, (parse_code & 0x0C) == 0x0C ? AV_GET_BUFFER_FLAG_REF : 0)) < 0)
  1917.             return ret;
  1918.         s->current_picture = pic;
  1919.         s->plane[0].stride = pic->avframe->linesize[0];
  1920.         s->plane[1].stride = pic->avframe->linesize[1];
  1921.         s->plane[2].stride = pic->avframe->linesize[2];
  1922.  
  1923.         if (alloc_buffers(s, FFMAX3(FFABS(s->plane[0].stride), FFABS(s->plane[1].stride), FFABS(s->plane[2].stride))) < 0)
  1924.             return AVERROR(ENOMEM);
  1925.  
  1926.         /* [DIRAC_STD] 11.1 Picture parse. picture_parse() */
  1927.         ret = dirac_decode_picture_header(s);
  1928.         if (ret < 0)
  1929.             return ret;
  1930.  
  1931.         /* [DIRAC_STD] 13.0 Transform data syntax. transform_data() */
  1932.         ret = dirac_decode_frame_internal(s);
  1933.         if (ret < 0)
  1934.             return ret;
  1935.     }
  1936.     return 0;
  1937. }
  1938.  
  1939. static int dirac_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *pkt)
  1940. {
  1941.     DiracContext *s     = avctx->priv_data;
  1942.     AVFrame *picture    = data;
  1943.     uint8_t *buf        = pkt->data;
  1944.     int buf_size        = pkt->size;
  1945.     int i, buf_idx      = 0;
  1946.     int ret;
  1947.     unsigned data_unit_size;
  1948.  
  1949.     /* release unused frames */
  1950.     for (i = 0; i < MAX_FRAMES; i++)
  1951.         if (s->all_frames[i].avframe->data[0] && !s->all_frames[i].reference) {
  1952.             av_frame_unref(s->all_frames[i].avframe);
  1953.             memset(s->all_frames[i].interpolated, 0, sizeof(s->all_frames[i].interpolated));
  1954.         }
  1955.  
  1956.     s->current_picture = NULL;
  1957.     *got_frame = 0;
  1958.  
  1959.     /* end of stream, so flush delayed pics */
  1960.     if (buf_size == 0)
  1961.         return get_delayed_pic(s, (AVFrame *)data, got_frame);
  1962.  
  1963.     for (;;) {
  1964.         /*[DIRAC_STD] Here starts the code from parse_info() defined in 9.6
  1965.           [DIRAC_STD] PARSE_INFO_PREFIX = "BBCD" as defined in ISO/IEC 646
  1966.           BBCD start code search */
  1967.         for (; buf_idx + DATA_UNIT_HEADER_SIZE < buf_size; buf_idx++) {
  1968.             if (buf[buf_idx  ] == 'B' && buf[buf_idx+1] == 'B' &&
  1969.                 buf[buf_idx+2] == 'C' && buf[buf_idx+3] == 'D')
  1970.                 break;
  1971.         }
  1972.         /* BBCD found or end of data */
  1973.         if (buf_idx + DATA_UNIT_HEADER_SIZE >= buf_size)
  1974.             break;
  1975.  
  1976.         data_unit_size = AV_RB32(buf+buf_idx+5);
  1977.         if (data_unit_size > buf_size - buf_idx || !data_unit_size) {
  1978.             if(data_unit_size > buf_size - buf_idx)
  1979.             av_log(s->avctx, AV_LOG_ERROR,
  1980.                    "Data unit with size %d is larger than input buffer, discarding\n",
  1981.                    data_unit_size);
  1982.             buf_idx += 4;
  1983.             continue;
  1984.         }
  1985.         /* [DIRAC_STD] dirac_decode_data_unit makes reference to the while defined in 9.3 inside the function parse_sequence() */
  1986.         ret = dirac_decode_data_unit(avctx, buf+buf_idx, data_unit_size);
  1987.         if (ret < 0)
  1988.         {
  1989.             av_log(s->avctx, AV_LOG_ERROR,"Error in dirac_decode_data_unit\n");
  1990.             return ret;
  1991.         }
  1992.         buf_idx += data_unit_size;
  1993.     }
  1994.  
  1995.     if (!s->current_picture)
  1996.         return buf_size;
  1997.  
  1998.     if (s->current_picture->avframe->display_picture_number > s->frame_number) {
  1999.         DiracFrame *delayed_frame = remove_frame(s->delay_frames, s->frame_number);
  2000.  
  2001.         s->current_picture->reference |= DELAYED_PIC_REF;
  2002.  
  2003.         if (add_frame(s->delay_frames, MAX_DELAY, s->current_picture)) {
  2004.             int min_num = s->delay_frames[0]->avframe->display_picture_number;
  2005.             /* Too many delayed frames, so we display the frame with the lowest pts */
  2006.             av_log(avctx, AV_LOG_ERROR, "Delay frame overflow\n");
  2007.  
  2008.             for (i = 1; s->delay_frames[i]; i++)
  2009.                 if (s->delay_frames[i]->avframe->display_picture_number < min_num)
  2010.                     min_num = s->delay_frames[i]->avframe->display_picture_number;
  2011.  
  2012.             delayed_frame = remove_frame(s->delay_frames, min_num);
  2013.             add_frame(s->delay_frames, MAX_DELAY, s->current_picture);
  2014.         }
  2015.  
  2016.         if (delayed_frame) {
  2017.             delayed_frame->reference ^= DELAYED_PIC_REF;
  2018.             if((ret=av_frame_ref(data, delayed_frame->avframe)) < 0)
  2019.                 return ret;
  2020.             *got_frame = 1;
  2021.         }
  2022.     } else if (s->current_picture->avframe->display_picture_number == s->frame_number) {
  2023.         /* The right frame at the right time :-) */
  2024.         if((ret=av_frame_ref(data, s->current_picture->avframe)) < 0)
  2025.             return ret;
  2026.         *got_frame = 1;
  2027.     }
  2028.  
  2029.     if (*got_frame)
  2030.         s->frame_number = picture->display_picture_number + 1;
  2031.  
  2032.     return buf_idx;
  2033. }
  2034.  
  2035. AVCodec ff_dirac_decoder = {
  2036.     .name           = "dirac",
  2037.     .long_name      = NULL_IF_CONFIG_SMALL("BBC Dirac VC-2"),
  2038.     .type           = AVMEDIA_TYPE_VIDEO,
  2039.     .id             = AV_CODEC_ID_DIRAC,
  2040.     .priv_data_size = sizeof(DiracContext),
  2041.     .init           = dirac_decode_init,
  2042.     .close          = dirac_decode_end,
  2043.     .decode         = dirac_decode_frame,
  2044.     .capabilities   = AV_CODEC_CAP_DELAY,
  2045.     .flush          = dirac_decode_flush,
  2046. };
  2047.