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FFmpeg/libavcodec/adpcm.c

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  1. /*

  2.  * Copyright (c) 2001-2003 The ffmpeg Project

  3.  *

  4.  * This file is part of Libav.

  5.  *

  6.  * Libav is free software; you can redistribute it and/or

  7.  * modify it under the terms of the GNU Lesser General Public

  8.  * License as published by the Free Software Foundation; either

  9.  * version 2.1 of the License, or (at your option) any later version.

  10.  *

  11.  * Libav is distributed in the hope that it will be useful,

  12.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  13.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  14.  * Lesser General Public License for more details.

  15.  *

  16.  * You should have received a copy of the GNU Lesser General Public

  17.  * License along with Libav; if not, write to the Free Software

  18.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  19.  */

  20. #include "avcodec.h"

  21. #include "get_bits.h"

  22. #include "put_bits.h"

  23. #include "bytestream.h"

  24. #include "adpcm.h"

  25. #include "adpcm_data.h"

  26. 

  27. /**

  28.  * @file

  29.  * ADPCM decoders

  30.  * First version by Francois Revol (revol@free.fr)

  31.  * Fringe ADPCM codecs (e.g., DK3, DK4, Westwood)

  32.  *   by Mike Melanson (melanson@pcisys.net)

  33.  * CD-ROM XA ADPCM codec by BERO

  34.  * EA ADPCM decoder by Robin Kay (komadori@myrealbox.com)

  35.  * EA ADPCM R1/R2/R3 decoder by Peter Ross (pross@xvid.org)

  36.  * EA IMA EACS decoder by Peter Ross (pross@xvid.org)

  37.  * EA IMA SEAD decoder by Peter Ross (pross@xvid.org)

  38.  * EA ADPCM XAS decoder by Peter Ross (pross@xvid.org)

  39.  * MAXIS EA ADPCM decoder by Robert Marston (rmarston@gmail.com)

  40.  * THP ADPCM decoder by Marco Gerards (mgerards@xs4all.nl)

  41.  *

  42.  * Features and limitations:

  43.  *

  44.  * Reference documents:

  45.  * http://wiki.multimedia.cx/index.php?title=Category:ADPCM_Audio_Codecs

  46.  * http://www.pcisys.net/~melanson/codecs/simpleaudio.html [dead]

  47.  * http://www.geocities.com/SiliconValley/8682/aud3.txt [dead]

  48.  * http://openquicktime.sourceforge.net/

  49.  * XAnim sources (xa_codec.c) http://xanim.polter.net/

  50.  * http://www.cs.ucla.edu/~leec/mediabench/applications.html [dead]

  51.  * SoX source code http://sox.sourceforge.net/

  52.  *

  53.  * CD-ROM XA:

  54.  * http://ku-www.ss.titech.ac.jp/~yatsushi/xaadpcm.html [dead]

  55.  * vagpack & depack http://homepages.compuserve.de/bITmASTER32/psx-index.html [dead]

  56.  * readstr http://www.geocities.co.jp/Playtown/2004/

  57.  */

  58. 

  59. /* These are for CD-ROM XA ADPCM */

  60. static const int xa_adpcm_table[5][2] = {

  61.     {   0,   0 },

  62.     {  60,   0 },

  63.     { 115, -52 },

  64.     {  98, -55 },

  65.     { 122, -60 }

  66. };

  67. 

  68. static const int ea_adpcm_table[] = {

  69.     0,  240,  460,  392,

  70.     0,    0, -208, -220,

  71.     0,    1,    3,    4,

  72.     7,    8,   10,   11,

  73.     0,   -1,   -3,   -4

  74. };

  75. 

  76. // padded to zero where table size is less then 16

  77. static const int swf_index_tables[4][16] = {

  78.     /*2*/ { -1, 2 },

  79.     /*3*/ { -1, -1, 2, 4 },

  80.     /*4*/ { -1, -1, -1, -1, 2, 4, 6, 8 },

  81.     /*5*/ { -1, -1, -1, -1, -1, -1, -1, -1, 1, 2, 4, 6, 8, 10, 13, 16 }

  82. };

  83. 

  84. /* end of tables */

  85. 

  86. typedef struct ADPCMDecodeContext {

  87.     AVFrame frame;

  88.     ADPCMChannelStatus status[6];

  89.     int vqa_version;                /**< VQA version. Used for ADPCM_IMA_WS */

  90. } ADPCMDecodeContext;

  91. 

  92. static av_cold int adpcm_decode_init(AVCodecContext * avctx)

  93. {

  94.     ADPCMDecodeContext *c = avctx->priv_data;

  95.     unsigned int min_channels = 1;

  96.     unsigned int max_channels = 2;

  97. 

  98.     switch(avctx->codec->id) {

  99.     case CODEC_ID_ADPCM_EA:

  100.         min_channels = 2;

  101.         break;

  102.     case CODEC_ID_ADPCM_EA_R1:

  103.     case CODEC_ID_ADPCM_EA_R2:

  104.     case CODEC_ID_ADPCM_EA_R3:

  105.     case CODEC_ID_ADPCM_EA_XAS:

  106.         max_channels = 6;

  107.         break;

  108.     }

  109.     if (avctx->channels < min_channels || avctx->channels > max_channels) {

  110.         av_log(avctx, AV_LOG_ERROR, "Invalid number of channels\n");

  111.         return AVERROR(EINVAL);

  112.     }

  113. 

  114.     switch(avctx->codec->id) {

  115.     case CODEC_ID_ADPCM_CT:

  116.         c->status[0].step = c->status[1].step = 511;

  117.         break;

  118.     case CODEC_ID_ADPCM_IMA_WAV:

  119.         if (avctx->bits_per_coded_sample != 4) {

  120.             av_log(avctx, AV_LOG_ERROR, "Only 4-bit ADPCM IMA WAV files are supported\n");

  121.             return -1;

  122.         }

  123.         break;

  124.     case CODEC_ID_ADPCM_IMA_APC:

  125.         if (avctx->extradata && avctx->extradata_size >= 8) {

  126.             c->status[0].predictor = AV_RL32(avctx->extradata);

  127.             c->status[1].predictor = AV_RL32(avctx->extradata + 4);

  128.         }

  129.         break;

  130.     case CODEC_ID_ADPCM_IMA_WS:

  131.         if (avctx->extradata && avctx->extradata_size >= 42)

  132.             c->vqa_version = AV_RL16(avctx->extradata);

  133.         break;

  134.     default:

  135.         break;

  136.     }

  137.     avctx->sample_fmt = AV_SAMPLE_FMT_S16;

  138. 

  139.     avcodec_get_frame_defaults(&c->frame);

  140.     avctx->coded_frame = &c->frame;

  141. 

  142.     return 0;

  143. }

  144. 

  145. static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble, int shift)

  146. {

  147.     int step_index;

  148.     int predictor;

  149.     int sign, delta, diff, step;

  150. 

  151.     step = ff_adpcm_step_table[c->step_index];

  152.     step_index = c->step_index + ff_adpcm_index_table[(unsigned)nibble];

  153.     step_index = av_clip(step_index, 0, 88);

  154. 

  155.     sign = nibble & 8;

  156.     delta = nibble & 7;

  157.     /* perform direct multiplication instead of series of jumps proposed by

  158.      * the reference ADPCM implementation since modern CPUs can do the mults

  159.      * quickly enough */

  160.     diff = ((2 * delta + 1) * step) >> shift;

  161.     predictor = c->predictor;

  162.     if (sign) predictor -= diff;

  163.     else predictor += diff;

  164. 

  165.     c->predictor = av_clip_int16(predictor);

  166.     c->step_index = step_index;

  167. 

  168.     return (short)c->predictor;

  169. }

  170. 

  171. static inline int adpcm_ima_qt_expand_nibble(ADPCMChannelStatus *c, int nibble, int shift)

  172. {

  173.     int step_index;

  174.     int predictor;

  175.     int diff, step;

  176. 

  177.     step = ff_adpcm_step_table[c->step_index];

  178.     step_index = c->step_index + ff_adpcm_index_table[nibble];

  179.     step_index = av_clip(step_index, 0, 88);

  180. 

  181.     diff = step >> 3;

  182.     if (nibble & 4) diff += step;

  183.     if (nibble & 2) diff += step >> 1;

  184.     if (nibble & 1) diff += step >> 2;

  185. 

  186.     if (nibble & 8)

  187.         predictor = c->predictor - diff;

  188.     else

  189.         predictor = c->predictor + diff;

  190. 

  191.     c->predictor = av_clip_int16(predictor);

  192.     c->step_index = step_index;

  193. 

  194.     return c->predictor;

  195. }

  196. 

  197. static inline short adpcm_ms_expand_nibble(ADPCMChannelStatus *c, int nibble)

  198. {

  199.     int predictor;

  200. 

  201.     predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 64;

  202.     predictor += ((nibble & 0x08)?(nibble - 0x10):(nibble)) * c->idelta;

  203. 

  204.     c->sample2 = c->sample1;

  205.     c->sample1 = av_clip_int16(predictor);

  206.     c->idelta = (ff_adpcm_AdaptationTable[(int)nibble] * c->idelta) >> 8;

  207.     if (c->idelta < 16) c->idelta = 16;

  208. 

  209.     return c->sample1;

  210. }

  211. 

  212. static inline short adpcm_ct_expand_nibble(ADPCMChannelStatus *c, char nibble)

  213. {

  214.     int sign, delta, diff;

  215.     int new_step;

  216. 

  217.     sign = nibble & 8;

  218.     delta = nibble & 7;

  219.     /* perform direct multiplication instead of series of jumps proposed by

  220.      * the reference ADPCM implementation since modern CPUs can do the mults

  221.      * quickly enough */

  222.     diff = ((2 * delta + 1) * c->step) >> 3;

  223.     /* predictor update is not so trivial: predictor is multiplied on 254/256 before updating */

  224.     c->predictor = ((c->predictor * 254) >> 8) + (sign ? -diff : diff);

  225.     c->predictor = av_clip_int16(c->predictor);

  226.     /* calculate new step and clamp it to range 511..32767 */

  227.     new_step = (ff_adpcm_AdaptationTable[nibble & 7] * c->step) >> 8;

  228.     c->step = av_clip(new_step, 511, 32767);

  229. 

  230.     return (short)c->predictor;

  231. }

  232. 

  233. static inline short adpcm_sbpro_expand_nibble(ADPCMChannelStatus *c, char nibble, int size, int shift)

  234. {

  235.     int sign, delta, diff;

  236. 

  237.     sign = nibble & (1<<(size-1));

  238.     delta = nibble & ((1<<(size-1))-1);

  239.     diff = delta << (7 + c->step + shift);

  240. 

  241.     /* clamp result */

  242.     c->predictor = av_clip(c->predictor + (sign ? -diff : diff), -16384,16256);

  243. 

  244.     /* calculate new step */

  245.     if (delta >= (2*size - 3) && c->step < 3)

  246.         c->step++;

  247.     else if (delta == 0 && c->step > 0)

  248.         c->step--;

  249. 

  250.     return (short) c->predictor;

  251. }

  252. 

  253. static inline short adpcm_yamaha_expand_nibble(ADPCMChannelStatus *c, unsigned char nibble)

  254. {

  255.     if(!c->step) {

  256.         c->predictor = 0;

  257.         c->step = 127;

  258.     }

  259. 

  260.     c->predictor += (c->step * ff_adpcm_yamaha_difflookup[nibble]) / 8;

  261.     c->predictor = av_clip_int16(c->predictor);

  262.     c->step = (c->step * ff_adpcm_yamaha_indexscale[nibble]) >> 8;

  263.     c->step = av_clip(c->step, 127, 24567);

  264.     return c->predictor;

  265. }

  266. 

  267. static int xa_decode(AVCodecContext *avctx,

  268.                      short *out, const unsigned char *in,

  269.                      ADPCMChannelStatus *left, ADPCMChannelStatus *right, int inc)

  270. {

  271.     int i, j;

  272.     int shift,filter,f0,f1;

  273.     int s_1,s_2;

  274.     int d,s,t;

  275. 

  276.     for(i=0;i<4;i++) {

  277. 

  278.         shift  = 12 - (in[4+i*2] & 15);

  279.         filter = in[4+i*2] >> 4;

  280.         if (filter > 4) {

  281.             av_log(avctx, AV_LOG_ERROR,

  282.                    "Invalid XA-ADPCM filter %d (max. allowed is 4)\n",

  283.                    filter);

  284.             return AVERROR_INVALIDDATA;

  285.         }

  286.         f0 = xa_adpcm_table[filter][0];

  287.         f1 = xa_adpcm_table[filter][1];

  288. 

  289.         s_1 = left->sample1;

  290.         s_2 = left->sample2;

  291. 

  292.         for(j=0;j<28;j++) {

  293.             d = in[16+i+j*4];

  294. 

  295.             t = sign_extend(d, 4);

  296.             s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);

  297.             s_2 = s_1;

  298.             s_1 = av_clip_int16(s);

  299.             *out = s_1;

  300.             out += inc;

  301.         }

  302. 

  303.         if (inc==2) { /* stereo */

  304.             left->sample1 = s_1;

  305.             left->sample2 = s_2;

  306.             s_1 = right->sample1;

  307.             s_2 = right->sample2;

  308.             out = out + 1 - 28*2;

  309.         }

  310. 

  311.         shift  = 12 - (in[5+i*2] & 15);

  312.         filter = in[5+i*2] >> 4;

  313.         if (filter > 4) {

  314.             av_log(avctx, AV_LOG_ERROR,

  315.                    "Invalid XA-ADPCM filter %d (max. allowed is 4)\n",

  316.                    filter);

  317.             return AVERROR_INVALIDDATA;

  318.         }

  319.         f0 = xa_adpcm_table[filter][0];

  320.         f1 = xa_adpcm_table[filter][1];

  321. 

  322.         for(j=0;j<28;j++) {

  323.             d = in[16+i+j*4];

  324. 

  325.             t = sign_extend(d >> 4, 4);

  326.             s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);

  327.             s_2 = s_1;

  328.             s_1 = av_clip_int16(s);

  329.             *out = s_1;

  330.             out += inc;

  331.         }

  332. 

  333.         if (inc==2) { /* stereo */

  334.             right->sample1 = s_1;

  335.             right->sample2 = s_2;

  336.             out -= 1;

  337.         } else {

  338.             left->sample1 = s_1;

  339.             left->sample2 = s_2;

  340.         }

  341.     }

  342. 

  343.     return 0;

  344. }

  345. 

  346. /**

  347.  * Get the number of samples that will be decoded from the packet.

  348.  * In one case, this is actually the maximum number of samples possible to

  349.  * decode with the given buf_size.

  350.  *

  351.  * @param[out] coded_samples set to the number of samples as coded in the

  352.  *                           packet, or 0 if the codec does not encode the

  353.  *                           number of samples in each frame.

  354.  */

  355. static int get_nb_samples(AVCodecContext *avctx, const uint8_t *buf,

  356.                           GetByteContext *gb,

  357.                           int buf_size, int *coded_samples)

  358. {

  359.     ADPCMDecodeContext *s = avctx->priv_data;

  360.     int nb_samples        = 0;

  361.     int ch                = avctx->channels;

  362.     int has_coded_samples = 0;

  363.     int header_size;

  364. 

  365.     *coded_samples = 0;

  366. 

  367.     switch (avctx->codec->id) {

  368.     /* constant, only check buf_size */

  369.     case CODEC_ID_ADPCM_EA_XAS:

  370.         if (buf_size < 76 * ch)

  371.             return 0;

  372.         nb_samples = 128;

  373.         break;

  374.     case CODEC_ID_ADPCM_IMA_QT:

  375.         if (buf_size < 34 * ch)

  376.             return 0;

  377.         nb_samples = 64;

  378.         break;

  379.     /* simple 4-bit adpcm */

  380.     case CODEC_ID_ADPCM_CT:

  381.     case CODEC_ID_ADPCM_IMA_APC:

  382.     case CODEC_ID_ADPCM_IMA_EA_SEAD:

  383.     case CODEC_ID_ADPCM_IMA_WS:

  384.     case CODEC_ID_ADPCM_YAMAHA:

  385.         nb_samples = buf_size * 2 / ch;

  386.         break;

  387.     }

  388.     if (nb_samples)

  389.         return nb_samples;

  390. 

  391.     /* simple 4-bit adpcm, with header */

  392.     header_size = 0;

  393.     switch (avctx->codec->id) {

  394.         case CODEC_ID_ADPCM_4XM:

  395.         case CODEC_ID_ADPCM_IMA_ISS:     header_size = 4 * ch;      break;

  396.         case CODEC_ID_ADPCM_IMA_AMV:     header_size = 8;           break;

  397.         case CODEC_ID_ADPCM_IMA_SMJPEG:  header_size = 4;           break;

  398.     }

  399.     if (header_size > 0)

  400.         return (buf_size - header_size) * 2 / ch;

  401. 

  402.     /* more complex formats */

  403.     switch (avctx->codec->id) {

  404.     case CODEC_ID_ADPCM_EA:

  405.         has_coded_samples = 1;

  406.         if (buf_size < 4)

  407.             return 0;

  408.         *coded_samples  = AV_RL32(buf);

  409.         *coded_samples -= *coded_samples % 28;

  410.         nb_samples      = (buf_size - 12) / 30 * 28;

  411.         break;

  412.     case CODEC_ID_ADPCM_IMA_EA_EACS:

  413.         has_coded_samples = 1;

  414.         *coded_samples = bytestream2_get_le32(gb);

  415.         nb_samples     = (buf_size - (4 + 8 * ch)) * 2 / ch;

  416.         break;

  417.     case CODEC_ID_ADPCM_EA_MAXIS_XA:

  418.         nb_samples = ((buf_size - ch) / (2 * ch)) * 2 * ch;

  419.         break;

  420.     case CODEC_ID_ADPCM_EA_R1:

  421.     case CODEC_ID_ADPCM_EA_R2:

  422.     case CODEC_ID_ADPCM_EA_R3:

  423.         /* maximum number of samples */

  424.         /* has internal offsets and a per-frame switch to signal raw 16-bit */

  425.         has_coded_samples = 1;

  426.         if (buf_size < 4)

  427.             return 0;

  428.         switch (avctx->codec->id) {

  429.         case CODEC_ID_ADPCM_EA_R1:

  430.             header_size    = 4 + 9 * ch;

  431.             *coded_samples = AV_RL32(buf);

  432.             break;

  433.         case CODEC_ID_ADPCM_EA_R2:

  434.             header_size    = 4 + 5 * ch;

  435.             *coded_samples = AV_RL32(buf);

  436.             break;

  437.         case CODEC_ID_ADPCM_EA_R3:

  438.             header_size    = 4 + 5 * ch;

  439.             *coded_samples = AV_RB32(buf);

  440.             break;

  441.         }

  442.         *coded_samples -= *coded_samples % 28;

  443.         nb_samples      = (buf_size - header_size) * 2 / ch;

  444.         nb_samples     -= nb_samples % 28;

  445.         break;

  446.     case CODEC_ID_ADPCM_IMA_DK3:

  447.         if (avctx->block_align > 0)

  448.             buf_size = FFMIN(buf_size, avctx->block_align);

  449.         nb_samples = ((buf_size - 16) * 2 / 3 * 4) / ch;

  450.         break;

  451.     case CODEC_ID_ADPCM_IMA_DK4:

  452.         if (avctx->block_align > 0)

  453.             buf_size = FFMIN(buf_size, avctx->block_align);

  454.         nb_samples = 1 + (buf_size - 4 * ch) * 2 / ch;

  455.         break;

  456.     case CODEC_ID_ADPCM_IMA_WAV:

  457.         if (avctx->block_align > 0)

  458.             buf_size = FFMIN(buf_size, avctx->block_align);

  459.         nb_samples = 1 + (buf_size - 4 * ch) / (4 * ch) * 8;

  460.         break;

  461.     case CODEC_ID_ADPCM_MS:

  462.         if (avctx->block_align > 0)

  463.             buf_size = FFMIN(buf_size, avctx->block_align);

  464.         nb_samples = 2 + (buf_size - 7 * ch) * 2 / ch;

  465.         break;

  466.     case CODEC_ID_ADPCM_SBPRO_2:

  467.     case CODEC_ID_ADPCM_SBPRO_3:

  468.     case CODEC_ID_ADPCM_SBPRO_4:

  469.     {

  470.         int samples_per_byte;

  471.         switch (avctx->codec->id) {

  472.         case CODEC_ID_ADPCM_SBPRO_2: samples_per_byte = 4; break;

  473.         case CODEC_ID_ADPCM_SBPRO_3: samples_per_byte = 3; break;

  474.         case CODEC_ID_ADPCM_SBPRO_4: samples_per_byte = 2; break;

  475.         }

  476.         if (!s->status[0].step_index) {

  477.             nb_samples++;

  478.             buf_size -= ch;

  479.         }

  480.         nb_samples += buf_size * samples_per_byte / ch;

  481.         break;

  482.     }

  483.     case CODEC_ID_ADPCM_SWF:

  484.     {

  485.         int buf_bits       = buf_size * 8 - 2;

  486.         int nbits          = (buf[0] >> 6) + 2;

  487.         int block_hdr_size = 22 * ch;

  488.         int block_size     = block_hdr_size + nbits * ch * 4095;

  489.         int nblocks        = buf_bits / block_size;

  490.         int bits_left      = buf_bits - nblocks * block_size;

  491.         nb_samples         = nblocks * 4096;

  492.         if (bits_left >= block_hdr_size)

  493.             nb_samples += 1 + (bits_left - block_hdr_size) / (nbits * ch);

  494.         break;

  495.     }

  496.     case CODEC_ID_ADPCM_THP:

  497.         has_coded_samples = 1;

  498.         if (buf_size < 8)

  499.             return 0;

  500.         *coded_samples  = AV_RB32(&buf[4]);

  501.         *coded_samples -= *coded_samples % 14;

  502.         nb_samples      = (buf_size - 80) / (8 * ch) * 14;

  503.         break;

  504.     case CODEC_ID_ADPCM_XA:

  505.         nb_samples = (buf_size / 128) * 224 / ch;

  506.         break;

  507.     }

  508. 

  509.     /* validate coded sample count */

  510.     if (has_coded_samples && (*coded_samples <= 0 || *coded_samples > nb_samples))

  511.         return AVERROR_INVALIDDATA;

  512. 

  513.     return nb_samples;

  514. }

  515. 

  516. static int adpcm_decode_frame(AVCodecContext *avctx, void *data,

  517.                               int *got_frame_ptr, AVPacket *avpkt)

  518. {

  519.     const uint8_t *buf = avpkt->data;

  520.     int buf_size = avpkt->size;

  521.     ADPCMDecodeContext *c = avctx->priv_data;

  522.     ADPCMChannelStatus *cs;

  523.     int n, m, channel, i;

  524.     short *samples;

  525.     const uint8_t *src;

  526.     int st; /* stereo */

  527.     int count1, count2;

  528.     int nb_samples, coded_samples, ret;

  529.     GetByteContext gb;

  530. 

  531.     bytestream2_init(&gb, buf, buf_size);

  532.     nb_samples = get_nb_samples(avctx, buf, &gb, buf_size, &coded_samples);

  533.     if (nb_samples <= 0) {

  534.         av_log(avctx, AV_LOG_ERROR, "invalid number of samples in packet\n");

  535.         return AVERROR_INVALIDDATA;

  536.     }

  537. 

  538.     /* get output buffer */

  539.     c->frame.nb_samples = nb_samples;

  540.     if ((ret = avctx->get_buffer(avctx, &c->frame)) < 0) {

  541.         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

  542.         return ret;

  543.     }

  544.     samples = (short *)c->frame.data[0];

  545. 

  546.     /* use coded_samples when applicable */

  547.     /* it is always <= nb_samples, so the output buffer will be large enough */

  548.     if (coded_samples) {

  549.         if (coded_samples != nb_samples)

  550.             av_log(avctx, AV_LOG_WARNING, "mismatch in coded sample count\n");

  551.         c->frame.nb_samples = nb_samples = coded_samples;

  552.     }

  553. 

  554.     src = buf;

  555. 

  556.     st = avctx->channels == 2 ? 1 : 0;

  557. 

  558.     switch(avctx->codec->id) {

  559.     case CODEC_ID_ADPCM_IMA_QT:

  560.         /* In QuickTime, IMA is encoded by chunks of 34 bytes (=64 samples).

  561.            Channel data is interleaved per-chunk. */

  562.         for (channel = 0; channel < avctx->channels; channel++) {

  563.             int predictor;

  564.             int step_index;

  565.             cs = &(c->status[channel]);

  566.             /* (pppppp) (piiiiiii) */

  567. 

  568.             /* Bits 15-7 are the _top_ 9 bits of the 16-bit initial predictor value */

  569.             predictor = sign_extend(bytestream2_get_be16u(&gb), 16);

  570.             step_index = predictor & 0x7F;

  571.             predictor &= ~0x7F;

  572. 

  573.             if (cs->step_index == step_index) {

  574.                 int diff = predictor - cs->predictor;

  575.                 if (diff < 0)

  576.                     diff = - diff;

  577.                 if (diff > 0x7f)

  578.                     goto update;

  579.             } else {

  580.             update:

  581.                 cs->step_index = step_index;

  582.                 cs->predictor = predictor;

  583.             }

  584. 

  585.             if (cs->step_index > 88u){

  586.                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index[%d] = %i\n",

  587.                        channel, cs->step_index);

  588.                 return AVERROR_INVALIDDATA;

  589.             }

  590. 

  591.             samples = (short *)c->frame.data[0] + channel;

  592. 

  593.             for (m = 0; m < 32; m++) {

  594.                 int byte = bytestream2_get_byteu(&gb);

  595.                 *samples = adpcm_ima_qt_expand_nibble(cs, byte & 0x0F, 3);

  596.                 samples += avctx->channels;

  597.                 *samples = adpcm_ima_qt_expand_nibble(cs, byte >> 4  , 3);

  598.                 samples += avctx->channels;

  599.             }

  600.         }

  601.         break;

  602.     case CODEC_ID_ADPCM_IMA_WAV:

  603.         for(i=0; i<avctx->channels; i++){

  604.             cs = &(c->status[i]);

  605.             cs->predictor = *samples++ = sign_extend(bytestream2_get_le16u(&gb), 16);

  606. 

  607.             cs->step_index = sign_extend(bytestream2_get_le16u(&gb), 16);

  608.             if (cs->step_index > 88u){

  609.                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index[%d] = %i\n",

  610.                        i, cs->step_index);

  611.                 return AVERROR_INVALIDDATA;

  612.             }

  613.         }

  614. 

  615.         for (n = (nb_samples - 1) / 8; n > 0; n--) {

  616.             for (i = 0; i < avctx->channels; i++) {

  617.                 cs = &c->status[i];

  618.                 for (m = 0; m < 4; m++) {

  619.                     int v = bytestream2_get_byteu(&gb);

  620.                     *samples = adpcm_ima_expand_nibble(cs, v & 0x0F, 3);

  621.                     samples += avctx->channels;

  622.                     *samples = adpcm_ima_expand_nibble(cs, v >> 4  , 3);

  623.                     samples += avctx->channels;

  624.                 }

  625.                 samples -= 8 * avctx->channels - 1;

  626.             }

  627.             samples += 7 * avctx->channels;

  628.         }

  629.         break;

  630.     case CODEC_ID_ADPCM_4XM:

  631.         for (i = 0; i < avctx->channels; i++)

  632.             c->status[i].predictor = sign_extend(bytestream2_get_le16u(&gb), 16);

  633. 

  634.         for (i = 0; i < avctx->channels; i++) {

  635.             c->status[i].step_index = sign_extend(bytestream2_get_le16u(&gb), 16);

  636.             if (c->status[i].step_index > 88u) {

  637.                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index[%d] = %i\n",

  638.                        i, c->status[i].step_index);

  639.                 return AVERROR_INVALIDDATA;

  640.             }

  641.         }

  642. 

  643.         for (i = 0; i < avctx->channels; i++) {

  644.             samples = (short *)c->frame.data[0] + i;

  645.             cs = &c->status[i];

  646.             for (n = nb_samples >> 1; n > 0; n--) {

  647.                 int v = bytestream2_get_byteu(&gb);

  648.                 *samples = adpcm_ima_expand_nibble(cs, v & 0x0F, 4);

  649.                 samples += avctx->channels;

  650.                 *samples = adpcm_ima_expand_nibble(cs, v >> 4  , 4);

  651.                 samples += avctx->channels;

  652.             }

  653.         }

  654.         break;

  655.     case CODEC_ID_ADPCM_MS:

  656.     {

  657.         int block_predictor;

  658. 

  659.         block_predictor = bytestream2_get_byteu(&gb);

  660.         if (block_predictor > 6) {

  661.             av_log(avctx, AV_LOG_ERROR, "ERROR: block_predictor[0] = %d\n",

  662.                    block_predictor);

  663.             return AVERROR_INVALIDDATA;

  664.         }

  665.         c->status[0].coeff1 = ff_adpcm_AdaptCoeff1[block_predictor];

  666.         c->status[0].coeff2 = ff_adpcm_AdaptCoeff2[block_predictor];

  667.         if (st) {

  668.             block_predictor = bytestream2_get_byteu(&gb);

  669.             if (block_predictor > 6) {

  670.                 av_log(avctx, AV_LOG_ERROR, "ERROR: block_predictor[1] = %d\n",

  671.                        block_predictor);

  672.                 return AVERROR_INVALIDDATA;

  673.             }

  674.             c->status[1].coeff1 = ff_adpcm_AdaptCoeff1[block_predictor];

  675.             c->status[1].coeff2 = ff_adpcm_AdaptCoeff2[block_predictor];

  676.         }

  677.         c->status[0].idelta = sign_extend(bytestream2_get_le16u(&gb), 16);

  678.         if (st){

  679.             c->status[1].idelta = sign_extend(bytestream2_get_le16u(&gb), 16);

  680.         }

  681. 

  682.         c->status[0].sample1 = sign_extend(bytestream2_get_le16u(&gb), 16);

  683.         if (st) c->status[1].sample1 = sign_extend(bytestream2_get_le16u(&gb), 16);

  684.         c->status[0].sample2 = sign_extend(bytestream2_get_le16u(&gb), 16);

  685.         if (st) c->status[1].sample2 = sign_extend(bytestream2_get_le16u(&gb), 16);

  686. 

  687.         *samples++ = c->status[0].sample2;

  688.         if (st) *samples++ = c->status[1].sample2;

  689.         *samples++ = c->status[0].sample1;

  690.         if (st) *samples++ = c->status[1].sample1;

  691.         for(n = (nb_samples - 2) >> (1 - st); n > 0; n--) {

  692.             int byte = bytestream2_get_byteu(&gb);

  693.             *samples++ = adpcm_ms_expand_nibble(&c->status[0 ], byte >> 4  );

  694.             *samples++ = adpcm_ms_expand_nibble(&c->status[st], byte & 0x0F);

  695.         }

  696.         break;

  697.     }

  698.     case CODEC_ID_ADPCM_IMA_DK4:

  699.         for (channel = 0; channel < avctx->channels; channel++) {

  700.             cs = &c->status[channel];

  701.             cs->predictor  = *samples++ = sign_extend(bytestream2_get_le16u(&gb), 16);

  702.             cs->step_index = sign_extend(bytestream2_get_le16u(&gb), 16);

  703.             if (cs->step_index > 88u){

  704.                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index[%d] = %i\n",

  705.                        channel, cs->step_index);

  706.                 return AVERROR_INVALIDDATA;

  707.             }

  708.         }

  709.         for (n = nb_samples >> (1 - st); n > 0; n--) {

  710.             int v = bytestream2_get_byteu(&gb);

  711.             *samples++ = adpcm_ima_expand_nibble(&c->status[0 ], v >> 4  , 3);

  712.             *samples++ = adpcm_ima_expand_nibble(&c->status[st], v & 0x0F, 3);

  713.         }

  714.         break;

  715.     case CODEC_ID_ADPCM_IMA_DK3:

  716.     {

  717.         int last_byte = 0;

  718.         int nibble;

  719.         int decode_top_nibble_next = 0;

  720.         int diff_channel;

  721.         const int16_t *samples_end = samples + avctx->channels * nb_samples;

  722. 

  723.         bytestream2_skipu(&gb, 10);

  724.         c->status[0].predictor  = sign_extend(bytestream2_get_le16u(&gb), 16);

  725.         c->status[1].predictor  = sign_extend(bytestream2_get_le16u(&gb), 16);

  726.         c->status[0].step_index = bytestream2_get_byteu(&gb);

  727.         c->status[1].step_index = bytestream2_get_byteu(&gb);

  728.         if (c->status[0].step_index > 88u || c->status[1].step_index > 88u){

  729.             av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i/%i\n",

  730.                    c->status[0].step_index, c->status[1].step_index);

  731.             return AVERROR_INVALIDDATA;

  732.         }

  733.         /* sign extend the predictors */

  734.         diff_channel = c->status[1].predictor;

  735. 

  736.         /* DK3 ADPCM support macro */

  737. #define DK3_GET_NEXT_NIBBLE() \

  738.     if (decode_top_nibble_next) { \

  739.         nibble = last_byte >> 4; \

  740.         decode_top_nibble_next = 0; \

  741.     } else { \

  742.         last_byte = bytestream2_get_byteu(&gb); \

  743.         nibble = last_byte & 0x0F; \

  744.         decode_top_nibble_next = 1; \

  745.     }

  746. 

  747.         while (samples < samples_end) {

  748. 

  749.             /* for this algorithm, c->status[0] is the sum channel and

  750.              * c->status[1] is the diff channel */

  751. 

  752.             /* process the first predictor of the sum channel */

  753.             DK3_GET_NEXT_NIBBLE();

  754.             adpcm_ima_expand_nibble(&c->status[0], nibble, 3);

  755. 

  756.             /* process the diff channel predictor */

  757.             DK3_GET_NEXT_NIBBLE();

  758.             adpcm_ima_expand_nibble(&c->status[1], nibble, 3);

  759. 

  760.             /* process the first pair of stereo PCM samples */

  761.             diff_channel = (diff_channel + c->status[1].predictor) / 2;

  762.             *samples++ = c->status[0].predictor + c->status[1].predictor;

  763.             *samples++ = c->status[0].predictor - c->status[1].predictor;

  764. 

  765.             /* process the second predictor of the sum channel */

  766.             DK3_GET_NEXT_NIBBLE();

  767.             adpcm_ima_expand_nibble(&c->status[0], nibble, 3);

  768. 

  769.             /* process the second pair of stereo PCM samples */

  770.             diff_channel = (diff_channel + c->status[1].predictor) / 2;

  771.             *samples++ = c->status[0].predictor + c->status[1].predictor;

  772.             *samples++ = c->status[0].predictor - c->status[1].predictor;

  773.         }

  774.         break;

  775.     }

  776.     case CODEC_ID_ADPCM_IMA_ISS:

  777.         for (channel = 0; channel < avctx->channels; channel++) {

  778.             cs = &c->status[channel];

  779.             cs->predictor  = sign_extend(bytestream2_get_le16u(&gb), 16);

  780.             cs->step_index = sign_extend(bytestream2_get_le16u(&gb), 16);

  781.             if (cs->step_index > 88u){

  782.                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index[%d] = %i\n",

  783.                        channel, cs->step_index);

  784.                 return AVERROR_INVALIDDATA;

  785.             }

  786.         }

  787. 

  788.         for (n = nb_samples >> (1 - st); n > 0; n--) {

  789.             int v1, v2;

  790.             int v = bytestream2_get_byteu(&gb);

  791.             /* nibbles are swapped for mono */

  792.             if (st) {

  793.                 v1 = v >> 4;

  794.                 v2 = v & 0x0F;

  795.             } else {

  796.                 v2 = v >> 4;

  797.                 v1 = v & 0x0F;

  798.             }

  799.             *samples++ = adpcm_ima_expand_nibble(&c->status[0 ], v1, 3);

  800.             *samples++ = adpcm_ima_expand_nibble(&c->status[st], v2, 3);

  801.         }

  802.         break;

  803.     case CODEC_ID_ADPCM_IMA_APC:

  804.         while (bytestream2_get_bytes_left(&gb) > 0) {

  805.             int v = bytestream2_get_byteu(&gb);

  806.             *samples++ = adpcm_ima_expand_nibble(&c->status[0],  v >> 4  , 3);

  807.             *samples++ = adpcm_ima_expand_nibble(&c->status[st], v & 0x0F, 3);

  808.         }

  809.         break;

  810.     case CODEC_ID_ADPCM_IMA_WS:

  811.         if (c->vqa_version == 3) {

  812.             for (channel = 0; channel < avctx->channels; channel++) {

  813.                 int16_t *smp = samples + channel;

  814. 

  815.                 for (n = nb_samples / 2; n > 0; n--) {

  816.                     int v = bytestream2_get_byteu(&gb);

  817.                     *smp = adpcm_ima_expand_nibble(&c->status[channel], v >> 4  , 3);

  818.                     smp += avctx->channels;

  819.                     *smp = adpcm_ima_expand_nibble(&c->status[channel], v & 0x0F, 3);

  820.                     smp += avctx->channels;

  821.                 }

  822.             }

  823.         } else {

  824.             for (n = nb_samples / 2; n > 0; n--) {

  825.                 for (channel = 0; channel < avctx->channels; channel++) {

  826.                     int v = bytestream2_get_byteu(&gb);

  827.                     *samples++  = adpcm_ima_expand_nibble(&c->status[channel], v >> 4  , 3);

  828.                     samples[st] = adpcm_ima_expand_nibble(&c->status[channel], v & 0x0F, 3);

  829.                 }

  830.                 samples += avctx->channels;

  831.             }

  832.         }

  833.         bytestream2_seek(&gb, 0, SEEK_END);

  834.         break;

  835.     case CODEC_ID_ADPCM_XA:

  836.         while (bytestream2_get_bytes_left(&gb) >= 128) {

  837.             if ((ret = xa_decode(avctx, samples, buf + bytestream2_tell(&gb), &c->status[0],

  838.                                  &c->status[1], avctx->channels)) < 0)

  839.                 return ret;

  840.             bytestream2_skipu(&gb, 128);

  841.             samples += 28 * 8;

  842.         }

  843.         break;

  844.     case CODEC_ID_ADPCM_IMA_EA_EACS:

  845.         for (i=0; i<=st; i++) {

  846.             c->status[i].step_index = bytestream2_get_le32u(&gb);

  847.             if (c->status[i].step_index > 88u) {

  848.                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index[%d] = %i\n",

  849.                        i, c->status[i].step_index);

  850.                 return AVERROR_INVALIDDATA;

  851.             }

  852.         }

  853.         for (i=0; i<=st; i++)

  854.             c->status[i].predictor  = bytestream2_get_le32u(&gb);

  855. 

  856.         for (n = nb_samples >> (1 - st); n > 0; n--) {

  857.             int byte   = bytestream2_get_byteu(&gb);

  858.             *samples++ = adpcm_ima_expand_nibble(&c->status[0],  byte >> 4,   3);

  859.             *samples++ = adpcm_ima_expand_nibble(&c->status[st], byte & 0x0F, 3);

  860.         }

  861.         break;

  862.     case CODEC_ID_ADPCM_IMA_EA_SEAD:

  863.         for (n = nb_samples >> (1 - st); n > 0; n--) {

  864.             int byte = bytestream2_get_byteu(&gb);

  865.             *samples++ = adpcm_ima_expand_nibble(&c->status[0],  byte >> 4,   6);

  866.             *samples++ = adpcm_ima_expand_nibble(&c->status[st], byte & 0x0F, 6);

  867.         }

  868.         break;

  869.     case CODEC_ID_ADPCM_EA:

  870.     {

  871.         int32_t previous_left_sample, previous_right_sample;

  872.         int32_t current_left_sample, current_right_sample;

  873.         int32_t next_left_sample, next_right_sample;

  874.         int32_t coeff1l, coeff2l, coeff1r, coeff2r;

  875.         uint8_t shift_left, shift_right;

  876. 

  877.         /* Each EA ADPCM frame has a 12-byte header followed by 30-byte pieces,

  878.            each coding 28 stereo samples. */

  879. 

  880.         src += 4; // skip sample count (already read)

  881. 

  882.         current_left_sample   = (int16_t)bytestream_get_le16(&src);

  883.         previous_left_sample  = (int16_t)bytestream_get_le16(&src);

  884.         current_right_sample  = (int16_t)bytestream_get_le16(&src);

  885.         previous_right_sample = (int16_t)bytestream_get_le16(&src);

  886. 

  887.         for (count1 = 0; count1 < nb_samples / 28; count1++) {

  888.             coeff1l = ea_adpcm_table[ *src >> 4       ];

  889.             coeff2l = ea_adpcm_table[(*src >> 4  ) + 4];

  890.             coeff1r = ea_adpcm_table[*src & 0x0F];

  891.             coeff2r = ea_adpcm_table[(*src & 0x0F) + 4];

  892.             src++;

  893. 

  894.             shift_left  = 20 - (*src >> 4);

  895.             shift_right = 20 - (*src & 0x0F);

  896.             src++;

  897. 

  898.             for (count2 = 0; count2 < 28; count2++) {

  899.                 next_left_sample  = sign_extend(*src >> 4, 4) << shift_left;

  900.                 next_right_sample = sign_extend(*src,      4) << shift_right;

  901.                 src++;

  902. 

  903.                 next_left_sample = (next_left_sample +

  904.                     (current_left_sample * coeff1l) +

  905.                     (previous_left_sample * coeff2l) + 0x80) >> 8;

  906.                 next_right_sample = (next_right_sample +

  907.                     (current_right_sample * coeff1r) +

  908.                     (previous_right_sample * coeff2r) + 0x80) >> 8;

  909. 

  910.                 previous_left_sample = current_left_sample;

  911.                 current_left_sample = av_clip_int16(next_left_sample);

  912.                 previous_right_sample = current_right_sample;

  913.                 current_right_sample = av_clip_int16(next_right_sample);

  914.                 *samples++ = (unsigned short)current_left_sample;

  915.                 *samples++ = (unsigned short)current_right_sample;

  916.             }

  917.         }

  918. 

  919.         if (src - buf == buf_size - 2)

  920.             src += 2; // Skip terminating 0x0000

  921. 

  922.         break;

  923.     }

  924.     case CODEC_ID_ADPCM_EA_MAXIS_XA:

  925.     {

  926.         int coeff[2][2], shift[2];

  927. 

  928.         for(channel = 0; channel < avctx->channels; channel++) {

  929.             for (i=0; i<2; i++)

  930.                 coeff[channel][i] = ea_adpcm_table[(*src >> 4) + 4*i];

  931.             shift[channel] = 20 - (*src & 0x0F);

  932.             src++;

  933.         }

  934.         for (count1 = 0; count1 < nb_samples / 2; count1++) {

  935.             for(i = 4; i >= 0; i-=4) { /* Pairwise samples LL RR (st) or LL LL (mono) */

  936.                 for(channel = 0; channel < avctx->channels; channel++) {

  937.                     int32_t sample = sign_extend(src[channel] >> i, 4) << shift[channel];

  938.                     sample = (sample +

  939.                              c->status[channel].sample1 * coeff[channel][0] +

  940.                              c->status[channel].sample2 * coeff[channel][1] + 0x80) >> 8;

  941.                     c->status[channel].sample2 = c->status[channel].sample1;

  942.                     c->status[channel].sample1 = av_clip_int16(sample);

  943.                     *samples++ = c->status[channel].sample1;

  944.                 }

  945.             }

  946.             src+=avctx->channels;

  947.         }

  948.         /* consume whole packet */

  949.         src = buf + buf_size;

  950.         break;

  951.     }

  952.     case CODEC_ID_ADPCM_EA_R1:

  953.     case CODEC_ID_ADPCM_EA_R2:

  954.     case CODEC_ID_ADPCM_EA_R3: {

  955.         /* channel numbering

  956.            2chan: 0=fl, 1=fr

  957.            4chan: 0=fl, 1=rl, 2=fr, 3=rr

  958.            6chan: 0=fl, 1=c,  2=fr, 3=rl,  4=rr, 5=sub */

  959.         const int big_endian = avctx->codec->id == CODEC_ID_ADPCM_EA_R3;

  960.         int32_t previous_sample, current_sample, next_sample;

  961.         int32_t coeff1, coeff2;

  962.         uint8_t shift;

  963.         unsigned int channel;

  964.         uint16_t *samplesC;

  965.         const uint8_t *srcC;

  966.         const uint8_t *src_end = buf + buf_size;

  967.         int count = 0;

  968. 

  969.         src += 4; // skip sample count (already read)

  970. 

  971.         for (channel=0; channel<avctx->channels; channel++) {

  972.             int32_t offset = (big_endian ? bytestream_get_be32(&src)

  973.                                          : bytestream_get_le32(&src))

  974.                            + (avctx->channels-channel-1) * 4;

  975. 

  976.             if ((offset < 0) || (offset >= src_end - src - 4)) break;

  977.             srcC  = src + offset;

  978.             samplesC = samples + channel;

  979. 

  980.             if (avctx->codec->id == CODEC_ID_ADPCM_EA_R1) {

  981.                 current_sample  = (int16_t)bytestream_get_le16(&srcC);

  982.                 previous_sample = (int16_t)bytestream_get_le16(&srcC);

  983.             } else {

  984.                 current_sample  = c->status[channel].predictor;

  985.                 previous_sample = c->status[channel].prev_sample;

  986.             }

  987. 

  988.             for (count1 = 0; count1 < nb_samples / 28; count1++) {

  989.                 if (*srcC == 0xEE) {  /* only seen in R2 and R3 */

  990.                     srcC++;

  991.                     if (srcC > src_end - 30*2) break;

  992.                     current_sample  = (int16_t)bytestream_get_be16(&srcC);

  993.                     previous_sample = (int16_t)bytestream_get_be16(&srcC);

  994. 

  995.                     for (count2=0; count2<28; count2++) {

  996.                         *samplesC = (int16_t)bytestream_get_be16(&srcC);

  997.                         samplesC += avctx->channels;

  998.                     }

  999.                 } else {

  1000.                     coeff1 = ea_adpcm_table[ *srcC>>4     ];

  1001.                     coeff2 = ea_adpcm_table[(*srcC>>4) + 4];

  1002.                     shift = 20 - (*srcC++ & 0x0F);

  1003. 

  1004.                     if (srcC > src_end - 14) break;

  1005.                     for (count2=0; count2<28; count2++) {

  1006.                         if (count2 & 1)

  1007.                             next_sample = sign_extend(*srcC++,    4) << shift;

  1008.                         else

  1009.                             next_sample = sign_extend(*srcC >> 4, 4) << shift;

  1010. 

  1011.                         next_sample += (current_sample  * coeff1) +

  1012.                                        (previous_sample * coeff2);

  1013.                         next_sample = av_clip_int16(next_sample >> 8);

  1014. 

  1015.                         previous_sample = current_sample;

  1016.                         current_sample  = next_sample;

  1017.                         *samplesC = current_sample;

  1018.                         samplesC += avctx->channels;

  1019.                     }

  1020.                 }

  1021.             }

  1022.             if (!count) {

  1023.                 count = count1;

  1024.             } else if (count != count1) {

  1025.                 av_log(avctx, AV_LOG_WARNING, "per-channel sample count mismatch\n");

  1026.                 count = FFMAX(count, count1);

  1027.             }

  1028. 

  1029.             if (avctx->codec->id != CODEC_ID_ADPCM_EA_R1) {

  1030.                 c->status[channel].predictor   = current_sample;

  1031.                 c->status[channel].prev_sample = previous_sample;

  1032.             }

  1033.         }

  1034. 

  1035.         c->frame.nb_samples = count * 28;

  1036.         src = src_end;

  1037.         break;

  1038.     }

  1039.     case CODEC_ID_ADPCM_EA_XAS:

  1040.         for (channel=0; channel<avctx->channels; channel++) {

  1041.             int coeff[2][4], shift[4];

  1042.             short *s2, *s = &samples[channel];

  1043.             for (n=0; n<4; n++, s+=32*avctx->channels) {

  1044.                 for (i=0; i<2; i++)

  1045.                     coeff[i][n] = ea_adpcm_table[(src[0]&0x0F)+4*i];

  1046.                 shift[n] = 20 - (src[2] & 0x0F);

  1047.                 for (s2=s, i=0; i<2; i++, src+=2, s2+=avctx->channels)

  1048.                     s2[0] = (src[0]&0xF0) + (src[1]<<8);

  1049.             }

  1050. 

  1051.             for (m=2; m<32; m+=2) {

  1052.                 s = &samples[m*avctx->channels + channel];

  1053.                 for (n=0; n<4; n++, src++, s+=32*avctx->channels) {

  1054.                     for (s2=s, i=0; i<8; i+=4, s2+=avctx->channels) {

  1055.                         int level = sign_extend(*src >> (4 - i), 4) << shift[n];

  1056.                         int pred  = s2[-1*avctx->channels] * coeff[0][n]

  1057.                                   + s2[-2*avctx->channels] * coeff[1][n];

  1058.                         s2[0] = av_clip_int16((level + pred + 0x80) >> 8);

  1059.                     }

  1060.                 }

  1061.             }

  1062.         }

  1063.         break;

  1064.     case CODEC_ID_ADPCM_IMA_AMV:

  1065.     case CODEC_ID_ADPCM_IMA_SMJPEG:

  1066.         if (avctx->codec->id == CODEC_ID_ADPCM_IMA_AMV) {

  1067.             c->status[0].predictor = sign_extend(bytestream_get_le16(&src), 16);

  1068.             c->status[0].step_index = av_clip(bytestream_get_le16(&src), 0, 88);

  1069.             src += 4;

  1070.         } else {

  1071.             c->status[0].predictor = sign_extend(bytestream_get_be16(&src), 16);

  1072.             c->status[0].step_index = av_clip(bytestream_get_byte(&src), 0, 88);

  1073.             src += 1;

  1074.         }

  1075. 

  1076.         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {

  1077.             char hi, lo;

  1078.             lo = *src & 0x0F;

  1079.             hi = *src >> 4;

  1080. 

  1081.             if (avctx->codec->id == CODEC_ID_ADPCM_IMA_AMV)

  1082.                 FFSWAP(char, hi, lo);

  1083. 

  1084.             *samples++ = adpcm_ima_expand_nibble(&c->status[0],

  1085.                 lo, 3);

  1086.             *samples++ = adpcm_ima_expand_nibble(&c->status[0],

  1087.                 hi, 3);

  1088.         }

  1089.         break;

  1090.     case CODEC_ID_ADPCM_CT:

  1091.         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {

  1092.             uint8_t v = *src;

  1093.             *samples++ = adpcm_ct_expand_nibble(&c->status[0 ], v >> 4  );

  1094.             *samples++ = adpcm_ct_expand_nibble(&c->status[st], v & 0x0F);

  1095.         }

  1096.         break;

  1097.     case CODEC_ID_ADPCM_SBPRO_4:

  1098.     case CODEC_ID_ADPCM_SBPRO_3:

  1099.     case CODEC_ID_ADPCM_SBPRO_2:

  1100.         if (!c->status[0].step_index) {

  1101.             /* the first byte is a raw sample */

  1102.             *samples++ = 128 * (*src++ - 0x80);

  1103.             if (st)

  1104.               *samples++ = 128 * (*src++ - 0x80);

  1105.             c->status[0].step_index = 1;

  1106.             nb_samples--;

  1107.         }

  1108.         if (avctx->codec->id == CODEC_ID_ADPCM_SBPRO_4) {

  1109.             for (n = nb_samples >> (1 - st); n > 0; n--, src++) {

  1110.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1111.                     src[0] >> 4, 4, 0);

  1112.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],

  1113.                     src[0] & 0x0F, 4, 0);

  1114.             }

  1115.         } else if (avctx->codec->id == CODEC_ID_ADPCM_SBPRO_3) {

  1116.             for (n = nb_samples / 3; n > 0; n--, src++) {

  1117.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1118.                      src[0] >> 5        , 3, 0);

  1119.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1120.                     (src[0] >> 2) & 0x07, 3, 0);

  1121.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1122.                     src[0] & 0x03, 2, 0);

  1123.             }

  1124.         } else {

  1125.             for (n = nb_samples >> (2 - st); n > 0; n--, src++) {

  1126.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1127.                      src[0] >> 6        , 2, 2);

  1128.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],

  1129.                     (src[0] >> 4) & 0x03, 2, 2);

  1130.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1131.                     (src[0] >> 2) & 0x03, 2, 2);

  1132.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],

  1133.                     src[0] & 0x03, 2, 2);

  1134.             }

  1135.         }

  1136.         break;

  1137.     case CODEC_ID_ADPCM_SWF:

  1138.     {

  1139.         GetBitContext gb;

  1140.         const int *table;

  1141.         int k0, signmask, nb_bits, count;

  1142.         int size = buf_size*8;

  1143. 

  1144.         init_get_bits(&gb, buf, size);

  1145. 

  1146.         //read bits & initial values

  1147.         nb_bits = get_bits(&gb, 2)+2;

  1148.         //av_log(NULL,AV_LOG_INFO,"nb_bits: %d\n", nb_bits);

  1149.         table = swf_index_tables[nb_bits-2];

  1150.         k0 = 1 << (nb_bits-2);

  1151.         signmask = 1 << (nb_bits-1);

  1152. 

  1153.         while (get_bits_count(&gb) <= size - 22*avctx->channels) {

  1154.             for (i = 0; i < avctx->channels; i++) {

  1155.                 *samples++ = c->status[i].predictor = get_sbits(&gb, 16);

  1156.                 c->status[i].step_index = get_bits(&gb, 6);

  1157.             }

  1158. 

  1159.             for (count = 0; get_bits_count(&gb) <= size - nb_bits*avctx->channels && count < 4095; count++) {

  1160.                 int i;

  1161. 

  1162.                 for (i = 0; i < avctx->channels; i++) {

  1163.                     // similar to IMA adpcm

  1164.                     int delta = get_bits(&gb, nb_bits);

  1165.                     int step = ff_adpcm_step_table[c->status[i].step_index];

  1166.                     long vpdiff = 0; // vpdiff = (delta+0.5)*step/4

  1167.                     int k = k0;

  1168. 

  1169.                     do {

  1170.                         if (delta & k)

  1171.                             vpdiff += step;

  1172.                         step >>= 1;

  1173.                         k >>= 1;

  1174.                     } while(k);

  1175.                     vpdiff += step;

  1176. 

  1177.                     if (delta & signmask)

  1178.                         c->status[i].predictor -= vpdiff;

  1179.                     else

  1180.                         c->status[i].predictor += vpdiff;

  1181. 

  1182.                     c->status[i].step_index += table[delta & (~signmask)];

  1183. 

  1184.                     c->status[i].step_index = av_clip(c->status[i].step_index, 0, 88);

  1185.                     c->status[i].predictor = av_clip_int16(c->status[i].predictor);

  1186. 

  1187.                     *samples++ = c->status[i].predictor;

  1188.                 }

  1189.             }

  1190.         }

  1191.         src += buf_size;

  1192.         break;

  1193.     }

  1194.     case CODEC_ID_ADPCM_YAMAHA:

  1195.         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {

  1196.             uint8_t v = *src;

  1197.             *samples++ = adpcm_yamaha_expand_nibble(&c->status[0 ], v & 0x0F);

  1198.             *samples++ = adpcm_yamaha_expand_nibble(&c->status[st], v >> 4  );

  1199.         }

  1200.         break;

  1201.     case CODEC_ID_ADPCM_THP:

  1202.     {

  1203.         int table[2][16];

  1204.         int prev[2][2];

  1205.         int ch;

  1206. 

  1207.         src += 4; // skip channel size

  1208.         src += 4; // skip number of samples (already read)

  1209. 

  1210.         for (i = 0; i < 32; i++)

  1211.             table[0][i] = (int16_t)bytestream_get_be16(&src);

  1212. 

  1213.         /* Initialize the previous sample.  */

  1214.         for (i = 0; i < 4; i++)

  1215.             prev[0][i] = (int16_t)bytestream_get_be16(&src);

  1216. 

  1217.         for (ch = 0; ch <= st; ch++) {

  1218.             samples = (short *)c->frame.data[0] + ch;

  1219. 

  1220.             /* Read in every sample for this channel.  */

  1221.             for (i = 0; i < nb_samples / 14; i++) {

  1222.                 int index = (*src >> 4) & 7;

  1223.                 unsigned int exp = *src++ & 15;

  1224.                 int factor1 = table[ch][index * 2];

  1225.                 int factor2 = table[ch][index * 2 + 1];

  1226. 

  1227.                 /* Decode 14 samples.  */

  1228.                 for (n = 0; n < 14; n++) {

  1229.                     int32_t sampledat;

  1230.                     if(n&1) sampledat = sign_extend(*src++, 4);

  1231.                     else    sampledat = sign_extend(*src >> 4, 4);

  1232. 

  1233.                     sampledat = ((prev[ch][0]*factor1

  1234.                                 + prev[ch][1]*factor2) >> 11) + (sampledat << exp);

  1235.                     *samples = av_clip_int16(sampledat);

  1236.                     prev[ch][1] = prev[ch][0];

  1237.                     prev[ch][0] = *samples++;

  1238. 

  1239.                     /* In case of stereo, skip one sample, this sample

  1240.                        is for the other channel.  */

  1241.                     samples += st;

  1242.                 }

  1243.             }

  1244.         }

  1245.         break;

  1246.     }

  1247. 

  1248.     default:

  1249.         return -1;

  1250.     }

  1251. 

  1252.     *got_frame_ptr   = 1;

  1253.     *(AVFrame *)data = c->frame;

  1254. 

  1255.     return src == buf ? bytestream2_tell(&gb) : src - buf;

  1256. }

  1257. 

  1258. 

  1259. #define ADPCM_DECODER(id_, name_, long_name_)               \

  1260. AVCodec ff_ ## name_ ## _decoder = {                        \

  1261.     .name           = #name_,                               \

  1262.     .type           = AVMEDIA_TYPE_AUDIO,                   \

  1263.     .id             = id_,                                  \

  1264.     .priv_data_size = sizeof(ADPCMDecodeContext),           \

  1265.     .init           = adpcm_decode_init,                    \

  1266.     .decode         = adpcm_decode_frame,                   \

  1267.     .capabilities   = CODEC_CAP_DR1,                        \

  1268.     .long_name      = NULL_IF_CONFIG_SMALL(long_name_),     \

  1269. }

  1270. 

  1271. /* Note: Do not forget to add new entries to the Makefile as well. */

  1272. ADPCM_DECODER(CODEC_ID_ADPCM_4XM, adpcm_4xm, "ADPCM 4X Movie");

  1273. ADPCM_DECODER(CODEC_ID_ADPCM_CT, adpcm_ct, "ADPCM Creative Technology");

  1274. ADPCM_DECODER(CODEC_ID_ADPCM_EA, adpcm_ea, "ADPCM Electronic Arts");

  1275. ADPCM_DECODER(CODEC_ID_ADPCM_EA_MAXIS_XA, adpcm_ea_maxis_xa, "ADPCM Electronic Arts Maxis CDROM XA");

  1276. ADPCM_DECODER(CODEC_ID_ADPCM_EA_R1, adpcm_ea_r1, "ADPCM Electronic Arts R1");

  1277. ADPCM_DECODER(CODEC_ID_ADPCM_EA_R2, adpcm_ea_r2, "ADPCM Electronic Arts R2");

  1278. ADPCM_DECODER(CODEC_ID_ADPCM_EA_R3, adpcm_ea_r3, "ADPCM Electronic Arts R3");

  1279. ADPCM_DECODER(CODEC_ID_ADPCM_EA_XAS, adpcm_ea_xas, "ADPCM Electronic Arts XAS");

  1280. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_AMV, adpcm_ima_amv, "ADPCM IMA AMV");

  1281. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_APC, adpcm_ima_apc, "ADPCM IMA CRYO APC");

  1282. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_DK3, adpcm_ima_dk3, "ADPCM IMA Duck DK3");

  1283. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_DK4, adpcm_ima_dk4, "ADPCM IMA Duck DK4");

  1284. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_EA_EACS, adpcm_ima_ea_eacs, "ADPCM IMA Electronic Arts EACS");

  1285. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_EA_SEAD, adpcm_ima_ea_sead, "ADPCM IMA Electronic Arts SEAD");

  1286. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_ISS, adpcm_ima_iss, "ADPCM IMA Funcom ISS");

  1287. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt, "ADPCM IMA QuickTime");

  1288. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_SMJPEG, adpcm_ima_smjpeg, "ADPCM IMA Loki SDL MJPEG");

  1289. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav, "ADPCM IMA WAV");

  1290. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_WS, adpcm_ima_ws, "ADPCM IMA Westwood");

  1291. ADPCM_DECODER(CODEC_ID_ADPCM_MS, adpcm_ms, "ADPCM Microsoft");

  1292. ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_2, adpcm_sbpro_2, "ADPCM Sound Blaster Pro 2-bit");

  1293. ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_3, adpcm_sbpro_3, "ADPCM Sound Blaster Pro 2.6-bit");

  1294. ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_4, adpcm_sbpro_4, "ADPCM Sound Blaster Pro 4-bit");

  1295. ADPCM_DECODER(CODEC_ID_ADPCM_SWF, adpcm_swf, "ADPCM Shockwave Flash");

  1296. ADPCM_DECODER(CODEC_ID_ADPCM_THP, adpcm_thp, "ADPCM Nintendo Gamecube THP");

  1297. ADPCM_DECODER(CODEC_ID_ADPCM_XA, adpcm_xa, "ADPCM CDROM XA");

  1298. ADPCM_DECODER(CODEC_ID_ADPCM_YAMAHA, adpcm_yamaha, "ADPCM Yamaha");