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  1. /*
  2.  * COOK compatible decoder
  3.  * Copyright (c) 2003 Sascha Sommer
  4.  * Copyright (c) 2005 Benjamin Larsson
  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.  * Cook compatible decoder. Bastardization of the G.722.1 standard.
  26.  * This decoder handles RealNetworks, RealAudio G2 data.
  27.  * Cook is identified by the codec name cook in RM files.
  28.  *
  29.  * To use this decoder, a calling application must supply the extradata
  30.  * bytes provided from the RM container; 8+ bytes for mono streams and
  31.  * 16+ for stereo streams (maybe more).
  32.  *
  33.  * Codec technicalities (all this assume a buffer length of 1024):
  34.  * Cook works with several different techniques to achieve its compression.
  35.  * In the timedomain the buffer is divided into 8 pieces and quantized. If
  36.  * two neighboring pieces have different quantization index a smooth
  37.  * quantization curve is used to get a smooth overlap between the different
  38.  * pieces.
  39.  * To get to the transformdomain Cook uses a modulated lapped transform.
  40.  * The transform domain has 50 subbands with 20 elements each. This
  41.  * means only a maximum of 50*20=1000 coefficients are used out of the 1024
  42.  * available.
  43.  */
  44.  
  45. #include "libavutil/channel_layout.h"
  46. #include "libavutil/lfg.h"
  47.  
  48. #include "audiodsp.h"
  49. #include "avcodec.h"
  50. #include "get_bits.h"
  51. #include "bytestream.h"
  52. #include "fft.h"
  53. #include "internal.h"
  54. #include "sinewin.h"
  55. #include "unary.h"
  56.  
  57. #include "cookdata.h"
  58.  
  59. /* the different Cook versions */
  60. #define MONO            0x1000001
  61. #define STEREO          0x1000002
  62. #define JOINT_STEREO    0x1000003
  63. #define MC_COOK         0x2000000   // multichannel Cook, not supported
  64.  
  65. #define SUBBAND_SIZE    20
  66. #define MAX_SUBPACKETS   5
  67.  
  68. typedef struct cook_gains {
  69.     int *now;
  70.     int *previous;
  71. } cook_gains;
  72.  
  73. typedef struct COOKSubpacket {
  74.     int                 ch_idx;
  75.     int                 size;
  76.     int                 num_channels;
  77.     int                 cookversion;
  78.     int                 subbands;
  79.     int                 js_subband_start;
  80.     int                 js_vlc_bits;
  81.     int                 samples_per_channel;
  82.     int                 log2_numvector_size;
  83.     unsigned int        channel_mask;
  84.     VLC                 channel_coupling;
  85.     int                 joint_stereo;
  86.     int                 bits_per_subpacket;
  87.     int                 bits_per_subpdiv;
  88.     int                 total_subbands;
  89.     int                 numvector_size;       // 1 << log2_numvector_size;
  90.  
  91.     float               mono_previous_buffer1[1024];
  92.     float               mono_previous_buffer2[1024];
  93.  
  94.     cook_gains          gains1;
  95.     cook_gains          gains2;
  96.     int                 gain_1[9];
  97.     int                 gain_2[9];
  98.     int                 gain_3[9];
  99.     int                 gain_4[9];
  100. } COOKSubpacket;
  101.  
  102. typedef struct cook {
  103.     /*
  104.      * The following 5 functions provide the lowlevel arithmetic on
  105.      * the internal audio buffers.
  106.      */
  107.     void (*scalar_dequant)(struct cook *q, int index, int quant_index,
  108.                            int *subband_coef_index, int *subband_coef_sign,
  109.                            float *mlt_p);
  110.  
  111.     void (*decouple)(struct cook *q,
  112.                      COOKSubpacket *p,
  113.                      int subband,
  114.                      float f1, float f2,
  115.                      float *decode_buffer,
  116.                      float *mlt_buffer1, float *mlt_buffer2);
  117.  
  118.     void (*imlt_window)(struct cook *q, float *buffer1,
  119.                         cook_gains *gains_ptr, float *previous_buffer);
  120.  
  121.     void (*interpolate)(struct cook *q, float *buffer,
  122.                         int gain_index, int gain_index_next);
  123.  
  124.     void (*saturate_output)(struct cook *q, float *out);
  125.  
  126.     AVCodecContext*     avctx;
  127.     AudioDSPContext     adsp;
  128.     GetBitContext       gb;
  129.     /* stream data */
  130.     int                 num_vectors;
  131.     int                 samples_per_channel;
  132.     /* states */
  133.     AVLFG               random_state;
  134.     int                 discarded_packets;
  135.  
  136.     /* transform data */
  137.     FFTContext          mdct_ctx;
  138.     float*              mlt_window;
  139.  
  140.     /* VLC data */
  141.     VLC                 envelope_quant_index[13];
  142.     VLC                 sqvh[7];          // scalar quantization
  143.  
  144.     /* generatable tables and related variables */
  145.     int                 gain_size_factor;
  146.     float               gain_table[23];
  147.  
  148.     /* data buffers */
  149.  
  150.     uint8_t*            decoded_bytes_buffer;
  151.     DECLARE_ALIGNED(32, float, mono_mdct_output)[2048];
  152.     float               decode_buffer_1[1024];
  153.     float               decode_buffer_2[1024];
  154.     float               decode_buffer_0[1060]; /* static allocation for joint decode */
  155.  
  156.     const float         *cplscales[5];
  157.     int                 num_subpackets;
  158.     COOKSubpacket       subpacket[MAX_SUBPACKETS];
  159. } COOKContext;
  160.  
  161. static float     pow2tab[127];
  162. static float rootpow2tab[127];
  163.  
  164. /*************** init functions ***************/
  165.  
  166. /* table generator */
  167. static av_cold void init_pow2table(void)
  168. {
  169.     int i;
  170.     for (i = -63; i < 64; i++) {
  171.         pow2tab[63 + i] = pow(2, i);
  172.         rootpow2tab[63 + i] = sqrt(pow(2, i));
  173.     }
  174. }
  175.  
  176. /* table generator */
  177. static av_cold void init_gain_table(COOKContext *q)
  178. {
  179.     int i;
  180.     q->gain_size_factor = q->samples_per_channel / 8;
  181.     for (i = 0; i < 23; i++)
  182.         q->gain_table[i] = pow(pow2tab[i + 52],
  183.                                (1.0 / (double) q->gain_size_factor));
  184. }
  185.  
  186.  
  187. static av_cold int init_cook_vlc_tables(COOKContext *q)
  188. {
  189.     int i, result;
  190.  
  191.     result = 0;
  192.     for (i = 0; i < 13; i++) {
  193.         result |= init_vlc(&q->envelope_quant_index[i], 9, 24,
  194.                            envelope_quant_index_huffbits[i], 1, 1,
  195.                            envelope_quant_index_huffcodes[i], 2, 2, 0);
  196.     }
  197.     av_log(q->avctx, AV_LOG_DEBUG, "sqvh VLC init\n");
  198.     for (i = 0; i < 7; i++) {
  199.         result |= init_vlc(&q->sqvh[i], vhvlcsize_tab[i], vhsize_tab[i],
  200.                            cvh_huffbits[i], 1, 1,
  201.                            cvh_huffcodes[i], 2, 2, 0);
  202.     }
  203.  
  204.     for (i = 0; i < q->num_subpackets; i++) {
  205.         if (q->subpacket[i].joint_stereo == 1) {
  206.             result |= init_vlc(&q->subpacket[i].channel_coupling, 6,
  207.                                (1 << q->subpacket[i].js_vlc_bits) - 1,
  208.                                ccpl_huffbits[q->subpacket[i].js_vlc_bits - 2], 1, 1,
  209.                                ccpl_huffcodes[q->subpacket[i].js_vlc_bits - 2], 2, 2, 0);
  210.             av_log(q->avctx, AV_LOG_DEBUG, "subpacket %i Joint-stereo VLC used.\n", i);
  211.         }
  212.     }
  213.  
  214.     av_log(q->avctx, AV_LOG_DEBUG, "VLC tables initialized.\n");
  215.     return result;
  216. }
  217.  
  218. static av_cold int init_cook_mlt(COOKContext *q)
  219. {
  220.     int j, ret;
  221.     int mlt_size = q->samples_per_channel;
  222.  
  223.     if ((q->mlt_window = av_malloc_array(mlt_size, sizeof(*q->mlt_window))) == 0)
  224.         return AVERROR(ENOMEM);
  225.  
  226.     /* Initialize the MLT window: simple sine window. */
  227.     ff_sine_window_init(q->mlt_window, mlt_size);
  228.     for (j = 0; j < mlt_size; j++)
  229.         q->mlt_window[j] *= sqrt(2.0 / q->samples_per_channel);
  230.  
  231.     /* Initialize the MDCT. */
  232.     if ((ret = ff_mdct_init(&q->mdct_ctx, av_log2(mlt_size) + 1, 1, 1.0 / 32768.0))) {
  233.         av_freep(&q->mlt_window);
  234.         return ret;
  235.     }
  236.     av_log(q->avctx, AV_LOG_DEBUG, "MDCT initialized, order = %d.\n",
  237.            av_log2(mlt_size) + 1);
  238.  
  239.     return 0;
  240. }
  241.  
  242. static av_cold void init_cplscales_table(COOKContext *q)
  243. {
  244.     int i;
  245.     for (i = 0; i < 5; i++)
  246.         q->cplscales[i] = cplscales[i];
  247. }
  248.  
  249. /*************** init functions end ***********/
  250.  
  251. #define DECODE_BYTES_PAD1(bytes) (3 - ((bytes) + 3) % 4)
  252. #define DECODE_BYTES_PAD2(bytes) ((bytes) % 4 + DECODE_BYTES_PAD1(2 * (bytes)))
  253.  
  254. /**
  255.  * Cook indata decoding, every 32 bits are XORed with 0x37c511f2.
  256.  * Why? No idea, some checksum/error detection method maybe.
  257.  *
  258.  * Out buffer size: extra bytes are needed to cope with
  259.  * padding/misalignment.
  260.  * Subpackets passed to the decoder can contain two, consecutive
  261.  * half-subpackets, of identical but arbitrary size.
  262.  *          1234 1234 1234 1234  extraA extraB
  263.  * Case 1:  AAAA BBBB              0      0
  264.  * Case 2:  AAAA ABBB BB--         3      3
  265.  * Case 3:  AAAA AABB BBBB         2      2
  266.  * Case 4:  AAAA AAAB BBBB BB--    1      5
  267.  *
  268.  * Nice way to waste CPU cycles.
  269.  *
  270.  * @param inbuffer  pointer to byte array of indata
  271.  * @param out       pointer to byte array of outdata
  272.  * @param bytes     number of bytes
  273.  */
  274. static inline int decode_bytes(const uint8_t *inbuffer, uint8_t *out, int bytes)
  275. {
  276.     static const uint32_t tab[4] = {
  277.         AV_BE2NE32C(0x37c511f2u), AV_BE2NE32C(0xf237c511u),
  278.         AV_BE2NE32C(0x11f237c5u), AV_BE2NE32C(0xc511f237u),
  279.     };
  280.     int i, off;
  281.     uint32_t c;
  282.     const uint32_t *buf;
  283.     uint32_t *obuf = (uint32_t *) out;
  284.     /* FIXME: 64 bit platforms would be able to do 64 bits at a time.
  285.      * I'm too lazy though, should be something like
  286.      * for (i = 0; i < bitamount / 64; i++)
  287.      *     (int64_t) out[i] = 0x37c511f237c511f2 ^ av_be2ne64(int64_t) in[i]);
  288.      * Buffer alignment needs to be checked. */
  289.  
  290.     off = (intptr_t) inbuffer & 3;
  291.     buf = (const uint32_t *) (inbuffer - off);
  292.     c = tab[off];
  293.     bytes += 3 + off;
  294.     for (i = 0; i < bytes / 4; i++)
  295.         obuf[i] = c ^ buf[i];
  296.  
  297.     return off;
  298. }
  299.  
  300. static av_cold int cook_decode_close(AVCodecContext *avctx)
  301. {
  302.     int i;
  303.     COOKContext *q = avctx->priv_data;
  304.     av_log(avctx, AV_LOG_DEBUG, "Deallocating memory.\n");
  305.  
  306.     /* Free allocated memory buffers. */
  307.     av_freep(&q->mlt_window);
  308.     av_freep(&q->decoded_bytes_buffer);
  309.  
  310.     /* Free the transform. */
  311.     ff_mdct_end(&q->mdct_ctx);
  312.  
  313.     /* Free the VLC tables. */
  314.     for (i = 0; i < 13; i++)
  315.         ff_free_vlc(&q->envelope_quant_index[i]);
  316.     for (i = 0; i < 7; i++)
  317.         ff_free_vlc(&q->sqvh[i]);
  318.     for (i = 0; i < q->num_subpackets; i++)
  319.         ff_free_vlc(&q->subpacket[i].channel_coupling);
  320.  
  321.     av_log(avctx, AV_LOG_DEBUG, "Memory deallocated.\n");
  322.  
  323.     return 0;
  324. }
  325.  
  326. /**
  327.  * Fill the gain array for the timedomain quantization.
  328.  *
  329.  * @param gb          pointer to the GetBitContext
  330.  * @param gaininfo    array[9] of gain indexes
  331.  */
  332. static void decode_gain_info(GetBitContext *gb, int *gaininfo)
  333. {
  334.     int i, n;
  335.  
  336.     n = get_unary(gb, 0, get_bits_left(gb));     // amount of elements*2 to update
  337.  
  338.     i = 0;
  339.     while (n--) {
  340.         int index = get_bits(gb, 3);
  341.         int gain = get_bits1(gb) ? get_bits(gb, 4) - 7 : -1;
  342.  
  343.         while (i <= index)
  344.             gaininfo[i++] = gain;
  345.     }
  346.     while (i <= 8)
  347.         gaininfo[i++] = 0;
  348. }
  349.  
  350. /**
  351.  * Create the quant index table needed for the envelope.
  352.  *
  353.  * @param q                 pointer to the COOKContext
  354.  * @param quant_index_table pointer to the array
  355.  */
  356. static int decode_envelope(COOKContext *q, COOKSubpacket *p,
  357.                            int *quant_index_table)
  358. {
  359.     int i, j, vlc_index;
  360.  
  361.     quant_index_table[0] = get_bits(&q->gb, 6) - 6; // This is used later in categorize
  362.  
  363.     for (i = 1; i < p->total_subbands; i++) {
  364.         vlc_index = i;
  365.         if (i >= p->js_subband_start * 2) {
  366.             vlc_index -= p->js_subband_start;
  367.         } else {
  368.             vlc_index /= 2;
  369.             if (vlc_index < 1)
  370.                 vlc_index = 1;
  371.         }
  372.         if (vlc_index > 13)
  373.             vlc_index = 13; // the VLC tables >13 are identical to No. 13
  374.  
  375.         j = get_vlc2(&q->gb, q->envelope_quant_index[vlc_index - 1].table,
  376.                      q->envelope_quant_index[vlc_index - 1].bits, 2);
  377.         quant_index_table[i] = quant_index_table[i - 1] + j - 12; // differential encoding
  378.         if (quant_index_table[i] > 63 || quant_index_table[i] < -63) {
  379.             av_log(q->avctx, AV_LOG_ERROR,
  380.                    "Invalid quantizer %d at position %d, outside [-63, 63] range\n",
  381.                    quant_index_table[i], i);
  382.             return AVERROR_INVALIDDATA;
  383.         }
  384.     }
  385.  
  386.     return 0;
  387. }
  388.  
  389. /**
  390.  * Calculate the category and category_index vector.
  391.  *
  392.  * @param q                     pointer to the COOKContext
  393.  * @param quant_index_table     pointer to the array
  394.  * @param category              pointer to the category array
  395.  * @param category_index        pointer to the category_index array
  396.  */
  397. static void categorize(COOKContext *q, COOKSubpacket *p, const int *quant_index_table,
  398.                        int *category, int *category_index)
  399. {
  400.     int exp_idx, bias, tmpbias1, tmpbias2, bits_left, num_bits, index, v, i, j;
  401.     int exp_index2[102] = { 0 };
  402.     int exp_index1[102] = { 0 };
  403.  
  404.     int tmp_categorize_array[128 * 2] = { 0 };
  405.     int tmp_categorize_array1_idx = p->numvector_size;
  406.     int tmp_categorize_array2_idx = p->numvector_size;
  407.  
  408.     bits_left = p->bits_per_subpacket - get_bits_count(&q->gb);
  409.  
  410.     if (bits_left > q->samples_per_channel)
  411.         bits_left = q->samples_per_channel +
  412.                     ((bits_left - q->samples_per_channel) * 5) / 8;
  413.  
  414.     bias = -32;
  415.  
  416.     /* Estimate bias. */
  417.     for (i = 32; i > 0; i = i / 2) {
  418.         num_bits = 0;
  419.         index    = 0;
  420.         for (j = p->total_subbands; j > 0; j--) {
  421.             exp_idx = av_clip_uintp2((i - quant_index_table[index] + bias) / 2, 3);
  422.             index++;
  423.             num_bits += expbits_tab[exp_idx];
  424.         }
  425.         if (num_bits >= bits_left - 32)
  426.             bias += i;
  427.     }
  428.  
  429.     /* Calculate total number of bits. */
  430.     num_bits = 0;
  431.     for (i = 0; i < p->total_subbands; i++) {
  432.         exp_idx = av_clip_uintp2((bias - quant_index_table[i]) / 2, 3);
  433.         num_bits += expbits_tab[exp_idx];
  434.         exp_index1[i] = exp_idx;
  435.         exp_index2[i] = exp_idx;
  436.     }
  437.     tmpbias1 = tmpbias2 = num_bits;
  438.  
  439.     for (j = 1; j < p->numvector_size; j++) {
  440.         if (tmpbias1 + tmpbias2 > 2 * bits_left) {  /* ---> */
  441.             int max = -999999;
  442.             index = -1;
  443.             for (i = 0; i < p->total_subbands; i++) {
  444.                 if (exp_index1[i] < 7) {
  445.                     v = (-2 * exp_index1[i]) - quant_index_table[i] + bias;
  446.                     if (v >= max) {
  447.                         max   = v;
  448.                         index = i;
  449.                     }
  450.                 }
  451.             }
  452.             if (index == -1)
  453.                 break;
  454.             tmp_categorize_array[tmp_categorize_array1_idx++] = index;
  455.             tmpbias1 -= expbits_tab[exp_index1[index]] -
  456.                         expbits_tab[exp_index1[index] + 1];
  457.             ++exp_index1[index];
  458.         } else {  /* <--- */
  459.             int min = 999999;
  460.             index = -1;
  461.             for (i = 0; i < p->total_subbands; i++) {
  462.                 if (exp_index2[i] > 0) {
  463.                     v = (-2 * exp_index2[i]) - quant_index_table[i] + bias;
  464.                     if (v < min) {
  465.                         min   = v;
  466.                         index = i;
  467.                     }
  468.                 }
  469.             }
  470.             if (index == -1)
  471.                 break;
  472.             tmp_categorize_array[--tmp_categorize_array2_idx] = index;
  473.             tmpbias2 -= expbits_tab[exp_index2[index]] -
  474.                         expbits_tab[exp_index2[index] - 1];
  475.             --exp_index2[index];
  476.         }
  477.     }
  478.  
  479.     for (i = 0; i < p->total_subbands; i++)
  480.         category[i] = exp_index2[i];
  481.  
  482.     for (i = 0; i < p->numvector_size - 1; i++)
  483.         category_index[i] = tmp_categorize_array[tmp_categorize_array2_idx++];
  484. }
  485.  
  486.  
  487. /**
  488.  * Expand the category vector.
  489.  *
  490.  * @param q                     pointer to the COOKContext
  491.  * @param category              pointer to the category array
  492.  * @param category_index        pointer to the category_index array
  493.  */
  494. static inline void expand_category(COOKContext *q, int *category,
  495.                                    int *category_index)
  496. {
  497.     int i;
  498.     for (i = 0; i < q->num_vectors; i++)
  499.     {
  500.         int idx = category_index[i];
  501.         if (++category[idx] >= FF_ARRAY_ELEMS(dither_tab))
  502.             --category[idx];
  503.     }
  504. }
  505.  
  506. /**
  507.  * The real requantization of the mltcoefs
  508.  *
  509.  * @param q                     pointer to the COOKContext
  510.  * @param index                 index
  511.  * @param quant_index           quantisation index
  512.  * @param subband_coef_index    array of indexes to quant_centroid_tab
  513.  * @param subband_coef_sign     signs of coefficients
  514.  * @param mlt_p                 pointer into the mlt buffer
  515.  */
  516. static void scalar_dequant_float(COOKContext *q, int index, int quant_index,
  517.                                  int *subband_coef_index, int *subband_coef_sign,
  518.                                  float *mlt_p)
  519. {
  520.     int i;
  521.     float f1;
  522.  
  523.     for (i = 0; i < SUBBAND_SIZE; i++) {
  524.         if (subband_coef_index[i]) {
  525.             f1 = quant_centroid_tab[index][subband_coef_index[i]];
  526.             if (subband_coef_sign[i])
  527.                 f1 = -f1;
  528.         } else {
  529.             /* noise coding if subband_coef_index[i] == 0 */
  530.             f1 = dither_tab[index];
  531.             if (av_lfg_get(&q->random_state) < 0x80000000)
  532.                 f1 = -f1;
  533.         }
  534.         mlt_p[i] = f1 * rootpow2tab[quant_index + 63];
  535.     }
  536. }
  537. /**
  538.  * Unpack the subband_coef_index and subband_coef_sign vectors.
  539.  *
  540.  * @param q                     pointer to the COOKContext
  541.  * @param category              pointer to the category array
  542.  * @param subband_coef_index    array of indexes to quant_centroid_tab
  543.  * @param subband_coef_sign     signs of coefficients
  544.  */
  545. static int unpack_SQVH(COOKContext *q, COOKSubpacket *p, int category,
  546.                        int *subband_coef_index, int *subband_coef_sign)
  547. {
  548.     int i, j;
  549.     int vlc, vd, tmp, result;
  550.  
  551.     vd = vd_tab[category];
  552.     result = 0;
  553.     for (i = 0; i < vpr_tab[category]; i++) {
  554.         vlc = get_vlc2(&q->gb, q->sqvh[category].table, q->sqvh[category].bits, 3);
  555.         if (p->bits_per_subpacket < get_bits_count(&q->gb)) {
  556.             vlc = 0;
  557.             result = 1;
  558.         }
  559.         for (j = vd - 1; j >= 0; j--) {
  560.             tmp = (vlc * invradix_tab[category]) / 0x100000;
  561.             subband_coef_index[vd * i + j] = vlc - tmp * (kmax_tab[category] + 1);
  562.             vlc = tmp;
  563.         }
  564.         for (j = 0; j < vd; j++) {
  565.             if (subband_coef_index[i * vd + j]) {
  566.                 if (get_bits_count(&q->gb) < p->bits_per_subpacket) {
  567.                     subband_coef_sign[i * vd + j] = get_bits1(&q->gb);
  568.                 } else {
  569.                     result = 1;
  570.                     subband_coef_sign[i * vd + j] = 0;
  571.                 }
  572.             } else {
  573.                 subband_coef_sign[i * vd + j] = 0;
  574.             }
  575.         }
  576.     }
  577.     return result;
  578. }
  579.  
  580.  
  581. /**
  582.  * Fill the mlt_buffer with mlt coefficients.
  583.  *
  584.  * @param q                 pointer to the COOKContext
  585.  * @param category          pointer to the category array
  586.  * @param quant_index_table pointer to the array
  587.  * @param mlt_buffer        pointer to mlt coefficients
  588.  */
  589. static void decode_vectors(COOKContext *q, COOKSubpacket *p, int *category,
  590.                            int *quant_index_table, float *mlt_buffer)
  591. {
  592.     /* A zero in this table means that the subband coefficient is
  593.        random noise coded. */
  594.     int subband_coef_index[SUBBAND_SIZE];
  595.     /* A zero in this table means that the subband coefficient is a
  596.        positive multiplicator. */
  597.     int subband_coef_sign[SUBBAND_SIZE];
  598.     int band, j;
  599.     int index = 0;
  600.  
  601.     for (band = 0; band < p->total_subbands; band++) {
  602.         index = category[band];
  603.         if (category[band] < 7) {
  604.             if (unpack_SQVH(q, p, category[band], subband_coef_index, subband_coef_sign)) {
  605.                 index = 7;
  606.                 for (j = 0; j < p->total_subbands; j++)
  607.                     category[band + j] = 7;
  608.             }
  609.         }
  610.         if (index >= 7) {
  611.             memset(subband_coef_index, 0, sizeof(subband_coef_index));
  612.             memset(subband_coef_sign,  0, sizeof(subband_coef_sign));
  613.         }
  614.         q->scalar_dequant(q, index, quant_index_table[band],
  615.                           subband_coef_index, subband_coef_sign,
  616.                           &mlt_buffer[band * SUBBAND_SIZE]);
  617.     }
  618.  
  619.     /* FIXME: should this be removed, or moved into loop above? */
  620.     if (p->total_subbands * SUBBAND_SIZE >= q->samples_per_channel)
  621.         return;
  622. }
  623.  
  624.  
  625. static int mono_decode(COOKContext *q, COOKSubpacket *p, float *mlt_buffer)
  626. {
  627.     int category_index[128] = { 0 };
  628.     int category[128]       = { 0 };
  629.     int quant_index_table[102];
  630.     int res, i;
  631.  
  632.     if ((res = decode_envelope(q, p, quant_index_table)) < 0)
  633.         return res;
  634.     q->num_vectors = get_bits(&q->gb, p->log2_numvector_size);
  635.     categorize(q, p, quant_index_table, category, category_index);
  636.     expand_category(q, category, category_index);
  637.     for (i=0; i<p->total_subbands; i++) {
  638.         if (category[i] > 7)
  639.             return AVERROR_INVALIDDATA;
  640.     }
  641.     decode_vectors(q, p, category, quant_index_table, mlt_buffer);
  642.  
  643.     return 0;
  644. }
  645.  
  646.  
  647. /**
  648.  * the actual requantization of the timedomain samples
  649.  *
  650.  * @param q                 pointer to the COOKContext
  651.  * @param buffer            pointer to the timedomain buffer
  652.  * @param gain_index        index for the block multiplier
  653.  * @param gain_index_next   index for the next block multiplier
  654.  */
  655. static void interpolate_float(COOKContext *q, float *buffer,
  656.                               int gain_index, int gain_index_next)
  657. {
  658.     int i;
  659.     float fc1, fc2;
  660.     fc1 = pow2tab[gain_index + 63];
  661.  
  662.     if (gain_index == gain_index_next) {             // static gain
  663.         for (i = 0; i < q->gain_size_factor; i++)
  664.             buffer[i] *= fc1;
  665.     } else {                                        // smooth gain
  666.         fc2 = q->gain_table[11 + (gain_index_next - gain_index)];
  667.         for (i = 0; i < q->gain_size_factor; i++) {
  668.             buffer[i] *= fc1;
  669.             fc1       *= fc2;
  670.         }
  671.     }
  672. }
  673.  
  674. /**
  675.  * Apply transform window, overlap buffers.
  676.  *
  677.  * @param q                 pointer to the COOKContext
  678.  * @param inbuffer          pointer to the mltcoefficients
  679.  * @param gains_ptr         current and previous gains
  680.  * @param previous_buffer   pointer to the previous buffer to be used for overlapping
  681.  */
  682. static void imlt_window_float(COOKContext *q, float *inbuffer,
  683.                               cook_gains *gains_ptr, float *previous_buffer)
  684. {
  685.     const float fc = pow2tab[gains_ptr->previous[0] + 63];
  686.     int i;
  687.     /* The weird thing here, is that the two halves of the time domain
  688.      * buffer are swapped. Also, the newest data, that we save away for
  689.      * next frame, has the wrong sign. Hence the subtraction below.
  690.      * Almost sounds like a complex conjugate/reverse data/FFT effect.
  691.      */
  692.  
  693.     /* Apply window and overlap */
  694.     for (i = 0; i < q->samples_per_channel; i++)
  695.         inbuffer[i] = inbuffer[i] * fc * q->mlt_window[i] -
  696.                       previous_buffer[i] * q->mlt_window[q->samples_per_channel - 1 - i];
  697. }
  698.  
  699. /**
  700.  * The modulated lapped transform, this takes transform coefficients
  701.  * and transforms them into timedomain samples.
  702.  * Apply transform window, overlap buffers, apply gain profile
  703.  * and buffer management.
  704.  *
  705.  * @param q                 pointer to the COOKContext
  706.  * @param inbuffer          pointer to the mltcoefficients
  707.  * @param gains_ptr         current and previous gains
  708.  * @param previous_buffer   pointer to the previous buffer to be used for overlapping
  709.  */
  710. static void imlt_gain(COOKContext *q, float *inbuffer,
  711.                       cook_gains *gains_ptr, float *previous_buffer)
  712. {
  713.     float *buffer0 = q->mono_mdct_output;
  714.     float *buffer1 = q->mono_mdct_output + q->samples_per_channel;
  715.     int i;
  716.  
  717.     /* Inverse modified discrete cosine transform */
  718.     q->mdct_ctx.imdct_calc(&q->mdct_ctx, q->mono_mdct_output, inbuffer);
  719.  
  720.     q->imlt_window(q, buffer1, gains_ptr, previous_buffer);
  721.  
  722.     /* Apply gain profile */
  723.     for (i = 0; i < 8; i++)
  724.         if (gains_ptr->now[i] || gains_ptr->now[i + 1])
  725.             q->interpolate(q, &buffer1[q->gain_size_factor * i],
  726.                            gains_ptr->now[i], gains_ptr->now[i + 1]);
  727.  
  728.     /* Save away the current to be previous block. */
  729.     memcpy(previous_buffer, buffer0,
  730.            q->samples_per_channel * sizeof(*previous_buffer));
  731. }
  732.  
  733.  
  734. /**
  735.  * function for getting the jointstereo coupling information
  736.  *
  737.  * @param q                 pointer to the COOKContext
  738.  * @param decouple_tab      decoupling array
  739.  */
  740. static int decouple_info(COOKContext *q, COOKSubpacket *p, int *decouple_tab)
  741. {
  742.     int i;
  743.     int vlc    = get_bits1(&q->gb);
  744.     int start  = cplband[p->js_subband_start];
  745.     int end    = cplband[p->subbands - 1];
  746.     int length = end - start + 1;
  747.  
  748.     if (start > end)
  749.         return 0;
  750.  
  751.     if (vlc)
  752.         for (i = 0; i < length; i++)
  753.             decouple_tab[start + i] = get_vlc2(&q->gb,
  754.                                                p->channel_coupling.table,
  755.                                                p->channel_coupling.bits, 2);
  756.     else
  757.         for (i = 0; i < length; i++) {
  758.             int v = get_bits(&q->gb, p->js_vlc_bits);
  759.             if (v == (1<<p->js_vlc_bits)-1) {
  760.                 av_log(q->avctx, AV_LOG_ERROR, "decouple value too large\n");
  761.                 return AVERROR_INVALIDDATA;
  762.             }
  763.             decouple_tab[start + i] = v;
  764.         }
  765.     return 0;
  766. }
  767.  
  768. /**
  769.  * function decouples a pair of signals from a single signal via multiplication.
  770.  *
  771.  * @param q                 pointer to the COOKContext
  772.  * @param subband           index of the current subband
  773.  * @param f1                multiplier for channel 1 extraction
  774.  * @param f2                multiplier for channel 2 extraction
  775.  * @param decode_buffer     input buffer
  776.  * @param mlt_buffer1       pointer to left channel mlt coefficients
  777.  * @param mlt_buffer2       pointer to right channel mlt coefficients
  778.  */
  779. static void decouple_float(COOKContext *q,
  780.                            COOKSubpacket *p,
  781.                            int subband,
  782.                            float f1, float f2,
  783.                            float *decode_buffer,
  784.                            float *mlt_buffer1, float *mlt_buffer2)
  785. {
  786.     int j, tmp_idx;
  787.     for (j = 0; j < SUBBAND_SIZE; j++) {
  788.         tmp_idx = ((p->js_subband_start + subband) * SUBBAND_SIZE) + j;
  789.         mlt_buffer1[SUBBAND_SIZE * subband + j] = f1 * decode_buffer[tmp_idx];
  790.         mlt_buffer2[SUBBAND_SIZE * subband + j] = f2 * decode_buffer[tmp_idx];
  791.     }
  792. }
  793.  
  794. /**
  795.  * function for decoding joint stereo data
  796.  *
  797.  * @param q                 pointer to the COOKContext
  798.  * @param mlt_buffer1       pointer to left channel mlt coefficients
  799.  * @param mlt_buffer2       pointer to right channel mlt coefficients
  800.  */
  801. static int joint_decode(COOKContext *q, COOKSubpacket *p,
  802.                         float *mlt_buffer_left, float *mlt_buffer_right)
  803. {
  804.     int i, j, res;
  805.     int decouple_tab[SUBBAND_SIZE] = { 0 };
  806.     float *decode_buffer = q->decode_buffer_0;
  807.     int idx, cpl_tmp;
  808.     float f1, f2;
  809.     const float *cplscale;
  810.  
  811.     memset(decode_buffer, 0, sizeof(q->decode_buffer_0));
  812.  
  813.     /* Make sure the buffers are zeroed out. */
  814.     memset(mlt_buffer_left,  0, 1024 * sizeof(*mlt_buffer_left));
  815.     memset(mlt_buffer_right, 0, 1024 * sizeof(*mlt_buffer_right));
  816.     if ((res = decouple_info(q, p, decouple_tab)) < 0)
  817.         return res;
  818.     if ((res = mono_decode(q, p, decode_buffer)) < 0)
  819.         return res;
  820.     /* The two channels are stored interleaved in decode_buffer. */
  821.     for (i = 0; i < p->js_subband_start; i++) {
  822.         for (j = 0; j < SUBBAND_SIZE; j++) {
  823.             mlt_buffer_left[i  * 20 + j] = decode_buffer[i * 40 + j];
  824.             mlt_buffer_right[i * 20 + j] = decode_buffer[i * 40 + 20 + j];
  825.         }
  826.     }
  827.  
  828.     /* When we reach js_subband_start (the higher frequencies)
  829.        the coefficients are stored in a coupling scheme. */
  830.     idx = (1 << p->js_vlc_bits) - 1;
  831.     for (i = p->js_subband_start; i < p->subbands; i++) {
  832.         cpl_tmp = cplband[i];
  833.         idx -= decouple_tab[cpl_tmp];
  834.         cplscale = q->cplscales[p->js_vlc_bits - 2];  // choose decoupler table
  835.         f1 = cplscale[decouple_tab[cpl_tmp] + 1];
  836.         f2 = cplscale[idx];
  837.         q->decouple(q, p, i, f1, f2, decode_buffer,
  838.                     mlt_buffer_left, mlt_buffer_right);
  839.         idx = (1 << p->js_vlc_bits) - 1;
  840.     }
  841.  
  842.     return 0;
  843. }
  844.  
  845. /**
  846.  * First part of subpacket decoding:
  847.  *  decode raw stream bytes and read gain info.
  848.  *
  849.  * @param q                 pointer to the COOKContext
  850.  * @param inbuffer          pointer to raw stream data
  851.  * @param gains_ptr         array of current/prev gain pointers
  852.  */
  853. static inline void decode_bytes_and_gain(COOKContext *q, COOKSubpacket *p,
  854.                                          const uint8_t *inbuffer,
  855.                                          cook_gains *gains_ptr)
  856. {
  857.     int offset;
  858.  
  859.     offset = decode_bytes(inbuffer, q->decoded_bytes_buffer,
  860.                           p->bits_per_subpacket / 8);
  861.     init_get_bits(&q->gb, q->decoded_bytes_buffer + offset,
  862.                   p->bits_per_subpacket);
  863.     decode_gain_info(&q->gb, gains_ptr->now);
  864.  
  865.     /* Swap current and previous gains */
  866.     FFSWAP(int *, gains_ptr->now, gains_ptr->previous);
  867. }
  868.  
  869. /**
  870.  * Saturate the output signal and interleave.
  871.  *
  872.  * @param q                 pointer to the COOKContext
  873.  * @param out               pointer to the output vector
  874.  */
  875. static void saturate_output_float(COOKContext *q, float *out)
  876. {
  877.     q->adsp.vector_clipf(out, q->mono_mdct_output + q->samples_per_channel,
  878.                          -1.0f, 1.0f, FFALIGN(q->samples_per_channel, 8));
  879. }
  880.  
  881.  
  882. /**
  883.  * Final part of subpacket decoding:
  884.  *  Apply modulated lapped transform, gain compensation,
  885.  *  clip and convert to integer.
  886.  *
  887.  * @param q                 pointer to the COOKContext
  888.  * @param decode_buffer     pointer to the mlt coefficients
  889.  * @param gains_ptr         array of current/prev gain pointers
  890.  * @param previous_buffer   pointer to the previous buffer to be used for overlapping
  891.  * @param out               pointer to the output buffer
  892.  */
  893. static inline void mlt_compensate_output(COOKContext *q, float *decode_buffer,
  894.                                          cook_gains *gains_ptr, float *previous_buffer,
  895.                                          float *out)
  896. {
  897.     imlt_gain(q, decode_buffer, gains_ptr, previous_buffer);
  898.     if (out)
  899.         q->saturate_output(q, out);
  900. }
  901.  
  902.  
  903. /**
  904.  * Cook subpacket decoding. This function returns one decoded subpacket,
  905.  * usually 1024 samples per channel.
  906.  *
  907.  * @param q                 pointer to the COOKContext
  908.  * @param inbuffer          pointer to the inbuffer
  909.  * @param outbuffer         pointer to the outbuffer
  910.  */
  911. static int decode_subpacket(COOKContext *q, COOKSubpacket *p,
  912.                             const uint8_t *inbuffer, float **outbuffer)
  913. {
  914.     int sub_packet_size = p->size;
  915.     int res;
  916.  
  917.     memset(q->decode_buffer_1, 0, sizeof(q->decode_buffer_1));
  918.     decode_bytes_and_gain(q, p, inbuffer, &p->gains1);
  919.  
  920.     if (p->joint_stereo) {
  921.         if ((res = joint_decode(q, p, q->decode_buffer_1, q->decode_buffer_2)) < 0)
  922.             return res;
  923.     } else {
  924.         if ((res = mono_decode(q, p, q->decode_buffer_1)) < 0)
  925.             return res;
  926.  
  927.         if (p->num_channels == 2) {
  928.             decode_bytes_and_gain(q, p, inbuffer + sub_packet_size / 2, &p->gains2);
  929.             if ((res = mono_decode(q, p, q->decode_buffer_2)) < 0)
  930.                 return res;
  931.         }
  932.     }
  933.  
  934.     mlt_compensate_output(q, q->decode_buffer_1, &p->gains1,
  935.                           p->mono_previous_buffer1,
  936.                           outbuffer ? outbuffer[p->ch_idx] : NULL);
  937.  
  938.     if (p->num_channels == 2) {
  939.         if (p->joint_stereo)
  940.             mlt_compensate_output(q, q->decode_buffer_2, &p->gains1,
  941.                                   p->mono_previous_buffer2,
  942.                                   outbuffer ? outbuffer[p->ch_idx + 1] : NULL);
  943.         else
  944.             mlt_compensate_output(q, q->decode_buffer_2, &p->gains2,
  945.                                   p->mono_previous_buffer2,
  946.                                   outbuffer ? outbuffer[p->ch_idx + 1] : NULL);
  947.     }
  948.  
  949.     return 0;
  950. }
  951.  
  952.  
  953. static int cook_decode_frame(AVCodecContext *avctx, void *data,
  954.                              int *got_frame_ptr, AVPacket *avpkt)
  955. {
  956.     AVFrame *frame     = data;
  957.     const uint8_t *buf = avpkt->data;
  958.     int buf_size = avpkt->size;
  959.     COOKContext *q = avctx->priv_data;
  960.     float **samples = NULL;
  961.     int i, ret;
  962.     int offset = 0;
  963.     int chidx = 0;
  964.  
  965.     if (buf_size < avctx->block_align)
  966.         return buf_size;
  967.  
  968.     /* get output buffer */
  969.     if (q->discarded_packets >= 2) {
  970.         frame->nb_samples = q->samples_per_channel;
  971.         if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
  972.             return ret;
  973.         samples = (float **)frame->extended_data;
  974.     }
  975.  
  976.     /* estimate subpacket sizes */
  977.     q->subpacket[0].size = avctx->block_align;
  978.  
  979.     for (i = 1; i < q->num_subpackets; i++) {
  980.         q->subpacket[i].size = 2 * buf[avctx->block_align - q->num_subpackets + i];
  981.         q->subpacket[0].size -= q->subpacket[i].size + 1;
  982.         if (q->subpacket[0].size < 0) {
  983.             av_log(avctx, AV_LOG_DEBUG,
  984.                    "frame subpacket size total > avctx->block_align!\n");
  985.             return AVERROR_INVALIDDATA;
  986.         }
  987.     }
  988.  
  989.     /* decode supbackets */
  990.     for (i = 0; i < q->num_subpackets; i++) {
  991.         q->subpacket[i].bits_per_subpacket = (q->subpacket[i].size * 8) >>
  992.                                               q->subpacket[i].bits_per_subpdiv;
  993.         q->subpacket[i].ch_idx = chidx;
  994.         av_log(avctx, AV_LOG_DEBUG,
  995.                "subpacket[%i] size %i js %i %i block_align %i\n",
  996.                i, q->subpacket[i].size, q->subpacket[i].joint_stereo, offset,
  997.                avctx->block_align);
  998.  
  999.         if ((ret = decode_subpacket(q, &q->subpacket[i], buf + offset, samples)) < 0)
  1000.             return ret;
  1001.         offset += q->subpacket[i].size;
  1002.         chidx += q->subpacket[i].num_channels;
  1003.         av_log(avctx, AV_LOG_DEBUG, "subpacket[%i] %i %i\n",
  1004.                i, q->subpacket[i].size * 8, get_bits_count(&q->gb));
  1005.     }
  1006.  
  1007.     /* Discard the first two frames: no valid audio. */
  1008.     if (q->discarded_packets < 2) {
  1009.         q->discarded_packets++;
  1010.         *got_frame_ptr = 0;
  1011.         return avctx->block_align;
  1012.     }
  1013.  
  1014.     *got_frame_ptr = 1;
  1015.  
  1016.     return avctx->block_align;
  1017. }
  1018.  
  1019. static void dump_cook_context(COOKContext *q)
  1020. {
  1021.     //int i=0;
  1022. #define PRINT(a, b) ff_dlog(q->avctx, " %s = %d\n", a, b);
  1023.     ff_dlog(q->avctx, "COOKextradata\n");
  1024.     ff_dlog(q->avctx, "cookversion=%x\n", q->subpacket[0].cookversion);
  1025.     if (q->subpacket[0].cookversion > STEREO) {
  1026.         PRINT("js_subband_start", q->subpacket[0].js_subband_start);
  1027.         PRINT("js_vlc_bits", q->subpacket[0].js_vlc_bits);
  1028.     }
  1029.     ff_dlog(q->avctx, "COOKContext\n");
  1030.     PRINT("nb_channels", q->avctx->channels);
  1031.     PRINT("bit_rate", q->avctx->bit_rate);
  1032.     PRINT("sample_rate", q->avctx->sample_rate);
  1033.     PRINT("samples_per_channel", q->subpacket[0].samples_per_channel);
  1034.     PRINT("subbands", q->subpacket[0].subbands);
  1035.     PRINT("js_subband_start", q->subpacket[0].js_subband_start);
  1036.     PRINT("log2_numvector_size", q->subpacket[0].log2_numvector_size);
  1037.     PRINT("numvector_size", q->subpacket[0].numvector_size);
  1038.     PRINT("total_subbands", q->subpacket[0].total_subbands);
  1039. }
  1040.  
  1041. /**
  1042.  * Cook initialization
  1043.  *
  1044.  * @param avctx     pointer to the AVCodecContext
  1045.  */
  1046. static av_cold int cook_decode_init(AVCodecContext *avctx)
  1047. {
  1048.     COOKContext *q = avctx->priv_data;
  1049.     const uint8_t *edata_ptr = avctx->extradata;
  1050.     const uint8_t *edata_ptr_end = edata_ptr + avctx->extradata_size;
  1051.     int extradata_size = avctx->extradata_size;
  1052.     int s = 0;
  1053.     unsigned int channel_mask = 0;
  1054.     int samples_per_frame = 0;
  1055.     int ret;
  1056.     q->avctx = avctx;
  1057.  
  1058.     /* Take care of the codec specific extradata. */
  1059.     if (extradata_size < 8) {
  1060.         av_log(avctx, AV_LOG_ERROR, "Necessary extradata missing!\n");
  1061.         return AVERROR_INVALIDDATA;
  1062.     }
  1063.     av_log(avctx, AV_LOG_DEBUG, "codecdata_length=%d\n", avctx->extradata_size);
  1064.  
  1065.     /* Take data from the AVCodecContext (RM container). */
  1066.     if (!avctx->channels) {
  1067.         av_log(avctx, AV_LOG_ERROR, "Invalid number of channels\n");
  1068.         return AVERROR_INVALIDDATA;
  1069.     }
  1070.  
  1071.     /* Initialize RNG. */
  1072.     av_lfg_init(&q->random_state, 0);
  1073.  
  1074.     ff_audiodsp_init(&q->adsp);
  1075.  
  1076.     while (edata_ptr < edata_ptr_end) {
  1077.         /* 8 for mono, 16 for stereo, ? for multichannel
  1078.            Swap to right endianness so we don't need to care later on. */
  1079.         if (extradata_size >= 8) {
  1080.             q->subpacket[s].cookversion = bytestream_get_be32(&edata_ptr);
  1081.             samples_per_frame           = bytestream_get_be16(&edata_ptr);
  1082.             q->subpacket[s].subbands = bytestream_get_be16(&edata_ptr);
  1083.             extradata_size -= 8;
  1084.         }
  1085.         if (extradata_size >= 8) {
  1086.             bytestream_get_be32(&edata_ptr);    // Unknown unused
  1087.             q->subpacket[s].js_subband_start = bytestream_get_be16(&edata_ptr);
  1088.             if (q->subpacket[s].js_subband_start >= 51) {
  1089.                 av_log(avctx, AV_LOG_ERROR, "js_subband_start %d is too large\n", q->subpacket[s].js_subband_start);
  1090.                 return AVERROR_INVALIDDATA;
  1091.             }
  1092.  
  1093.             q->subpacket[s].js_vlc_bits = bytestream_get_be16(&edata_ptr);
  1094.             extradata_size -= 8;
  1095.         }
  1096.  
  1097.         /* Initialize extradata related variables. */
  1098.         q->subpacket[s].samples_per_channel = samples_per_frame / avctx->channels;
  1099.         q->subpacket[s].bits_per_subpacket = avctx->block_align * 8;
  1100.  
  1101.         /* Initialize default data states. */
  1102.         q->subpacket[s].log2_numvector_size = 5;
  1103.         q->subpacket[s].total_subbands = q->subpacket[s].subbands;
  1104.         q->subpacket[s].num_channels = 1;
  1105.  
  1106.         /* Initialize version-dependent variables */
  1107.  
  1108.         av_log(avctx, AV_LOG_DEBUG, "subpacket[%i].cookversion=%x\n", s,
  1109.                q->subpacket[s].cookversion);
  1110.         q->subpacket[s].joint_stereo = 0;
  1111.         switch (q->subpacket[s].cookversion) {
  1112.         case MONO:
  1113.             if (avctx->channels != 1) {
  1114.                 avpriv_request_sample(avctx, "Container channels != 1");
  1115.                 return AVERROR_PATCHWELCOME;
  1116.             }
  1117.             av_log(avctx, AV_LOG_DEBUG, "MONO\n");
  1118.             break;
  1119.         case STEREO:
  1120.             if (avctx->channels != 1) {
  1121.                 q->subpacket[s].bits_per_subpdiv = 1;
  1122.                 q->subpacket[s].num_channels = 2;
  1123.             }
  1124.             av_log(avctx, AV_LOG_DEBUG, "STEREO\n");
  1125.             break;
  1126.         case JOINT_STEREO:
  1127.             if (avctx->channels != 2) {
  1128.                 avpriv_request_sample(avctx, "Container channels != 2");
  1129.                 return AVERROR_PATCHWELCOME;
  1130.             }
  1131.             av_log(avctx, AV_LOG_DEBUG, "JOINT_STEREO\n");
  1132.             if (avctx->extradata_size >= 16) {
  1133.                 q->subpacket[s].total_subbands = q->subpacket[s].subbands +
  1134.                                                  q->subpacket[s].js_subband_start;
  1135.                 q->subpacket[s].joint_stereo = 1;
  1136.                 q->subpacket[s].num_channels = 2;
  1137.             }
  1138.             if (q->subpacket[s].samples_per_channel > 256) {
  1139.                 q->subpacket[s].log2_numvector_size = 6;
  1140.             }
  1141.             if (q->subpacket[s].samples_per_channel > 512) {
  1142.                 q->subpacket[s].log2_numvector_size = 7;
  1143.             }
  1144.             break;
  1145.         case MC_COOK:
  1146.             av_log(avctx, AV_LOG_DEBUG, "MULTI_CHANNEL\n");
  1147.             if (extradata_size >= 4)
  1148.                 channel_mask |= q->subpacket[s].channel_mask = bytestream_get_be32(&edata_ptr);
  1149.  
  1150.             if (av_get_channel_layout_nb_channels(q->subpacket[s].channel_mask) > 1) {
  1151.                 q->subpacket[s].total_subbands = q->subpacket[s].subbands +
  1152.                                                  q->subpacket[s].js_subband_start;
  1153.                 q->subpacket[s].joint_stereo = 1;
  1154.                 q->subpacket[s].num_channels = 2;
  1155.                 q->subpacket[s].samples_per_channel = samples_per_frame >> 1;
  1156.  
  1157.                 if (q->subpacket[s].samples_per_channel > 256) {
  1158.                     q->subpacket[s].log2_numvector_size = 6;
  1159.                 }
  1160.                 if (q->subpacket[s].samples_per_channel > 512) {
  1161.                     q->subpacket[s].log2_numvector_size = 7;
  1162.                 }
  1163.             } else
  1164.                 q->subpacket[s].samples_per_channel = samples_per_frame;
  1165.  
  1166.             break;
  1167.         default:
  1168.             avpriv_request_sample(avctx, "Cook version %d",
  1169.                                   q->subpacket[s].cookversion);
  1170.             return AVERROR_PATCHWELCOME;
  1171.         }
  1172.  
  1173.         if (s > 1 && q->subpacket[s].samples_per_channel != q->samples_per_channel) {
  1174.             av_log(avctx, AV_LOG_ERROR, "different number of samples per channel!\n");
  1175.             return AVERROR_INVALIDDATA;
  1176.         } else
  1177.             q->samples_per_channel = q->subpacket[0].samples_per_channel;
  1178.  
  1179.  
  1180.         /* Initialize variable relations */
  1181.         q->subpacket[s].numvector_size = (1 << q->subpacket[s].log2_numvector_size);
  1182.  
  1183.         /* Try to catch some obviously faulty streams, othervise it might be exploitable */
  1184.         if (q->subpacket[s].total_subbands > 53) {
  1185.             avpriv_request_sample(avctx, "total_subbands > 53");
  1186.             return AVERROR_PATCHWELCOME;
  1187.         }
  1188.  
  1189.         if ((q->subpacket[s].js_vlc_bits > 6) ||
  1190.             (q->subpacket[s].js_vlc_bits < 2 * q->subpacket[s].joint_stereo)) {
  1191.             av_log(avctx, AV_LOG_ERROR, "js_vlc_bits = %d, only >= %d and <= 6 allowed!\n",
  1192.                    q->subpacket[s].js_vlc_bits, 2 * q->subpacket[s].joint_stereo);
  1193.             return AVERROR_INVALIDDATA;
  1194.         }
  1195.  
  1196.         if (q->subpacket[s].subbands > 50) {
  1197.             avpriv_request_sample(avctx, "subbands > 50");
  1198.             return AVERROR_PATCHWELCOME;
  1199.         }
  1200.         if (q->subpacket[s].subbands == 0) {
  1201.             avpriv_request_sample(avctx, "subbands = 0");
  1202.             return AVERROR_PATCHWELCOME;
  1203.         }
  1204.         q->subpacket[s].gains1.now      = q->subpacket[s].gain_1;
  1205.         q->subpacket[s].gains1.previous = q->subpacket[s].gain_2;
  1206.         q->subpacket[s].gains2.now      = q->subpacket[s].gain_3;
  1207.         q->subpacket[s].gains2.previous = q->subpacket[s].gain_4;
  1208.  
  1209.         if (q->num_subpackets + q->subpacket[s].num_channels > q->avctx->channels) {
  1210.             av_log(avctx, AV_LOG_ERROR, "Too many subpackets %d for channels %d\n", q->num_subpackets, q->avctx->channels);
  1211.             return AVERROR_INVALIDDATA;
  1212.         }
  1213.  
  1214.         q->num_subpackets++;
  1215.         s++;
  1216.         if (s > FFMIN(MAX_SUBPACKETS, avctx->block_align)) {
  1217.             avpriv_request_sample(avctx, "subpackets > %d", FFMIN(MAX_SUBPACKETS, avctx->block_align));
  1218.             return AVERROR_PATCHWELCOME;
  1219.         }
  1220.     }
  1221.     /* Generate tables */
  1222.     init_pow2table();
  1223.     init_gain_table(q);
  1224.     init_cplscales_table(q);
  1225.  
  1226.     if ((ret = init_cook_vlc_tables(q)))
  1227.         return ret;
  1228.  
  1229.  
  1230.     if (avctx->block_align >= UINT_MAX / 2)
  1231.         return AVERROR(EINVAL);
  1232.  
  1233.     /* Pad the databuffer with:
  1234.        DECODE_BYTES_PAD1 or DECODE_BYTES_PAD2 for decode_bytes(),
  1235.        AV_INPUT_BUFFER_PADDING_SIZE, for the bitstreamreader. */
  1236.     q->decoded_bytes_buffer =
  1237.         av_mallocz(avctx->block_align
  1238.                    + DECODE_BYTES_PAD1(avctx->block_align)
  1239.                    + AV_INPUT_BUFFER_PADDING_SIZE);
  1240.     if (!q->decoded_bytes_buffer)
  1241.         return AVERROR(ENOMEM);
  1242.  
  1243.     /* Initialize transform. */
  1244.     if ((ret = init_cook_mlt(q)))
  1245.         return ret;
  1246.  
  1247.     /* Initialize COOK signal arithmetic handling */
  1248.     if (1) {
  1249.         q->scalar_dequant  = scalar_dequant_float;
  1250.         q->decouple        = decouple_float;
  1251.         q->imlt_window     = imlt_window_float;
  1252.         q->interpolate     = interpolate_float;
  1253.         q->saturate_output = saturate_output_float;
  1254.     }
  1255.  
  1256.     /* Try to catch some obviously faulty streams, othervise it might be exploitable */
  1257.     if (q->samples_per_channel != 256 && q->samples_per_channel != 512 &&
  1258.         q->samples_per_channel != 1024) {
  1259.         avpriv_request_sample(avctx, "samples_per_channel = %d",
  1260.                               q->samples_per_channel);
  1261.         return AVERROR_PATCHWELCOME;
  1262.     }
  1263.  
  1264.     avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
  1265.     if (channel_mask)
  1266.         avctx->channel_layout = channel_mask;
  1267.     else
  1268.         avctx->channel_layout = (avctx->channels == 2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
  1269.  
  1270.  
  1271.     dump_cook_context(q);
  1272.  
  1273.     return 0;
  1274. }
  1275.  
  1276. AVCodec ff_cook_decoder = {
  1277.     .name           = "cook",
  1278.     .long_name      = NULL_IF_CONFIG_SMALL("Cook / Cooker / Gecko (RealAudio G2)"),
  1279.     .type           = AVMEDIA_TYPE_AUDIO,
  1280.     .id             = AV_CODEC_ID_COOK,
  1281.     .priv_data_size = sizeof(COOKContext),
  1282.     .init           = cook_decode_init,
  1283.     .close          = cook_decode_close,
  1284.     .decode         = cook_decode_frame,
  1285.     .capabilities   = AV_CODEC_CAP_DR1,
  1286.     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
  1287.                                                       AV_SAMPLE_FMT_NONE },
  1288. };
  1289.