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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. } ADPCMDecodeContext;

  90. 

  91. static av_cold int adpcm_decode_init(AVCodecContext * avctx)

  92. {

  93.     ADPCMDecodeContext *c = avctx->priv_data;

  94.     unsigned int min_channels = 1;

  95.     unsigned int max_channels = 2;

  96. 

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

  98.     case CODEC_ID_ADPCM_EA:

  99.         min_channels = 2;

  100.         break;

  101.     case CODEC_ID_ADPCM_EA_R1:

  102.     case CODEC_ID_ADPCM_EA_R2:

  103.     case CODEC_ID_ADPCM_EA_R3:

  104.     case CODEC_ID_ADPCM_EA_XAS:

  105.         max_channels = 6;

  106.         break;

  107.     }

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

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

  110.         return AVERROR(EINVAL);

  111.     }

  112. 

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

  114.     case CODEC_ID_ADPCM_CT:

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

  116.         break;

  117.     case CODEC_ID_ADPCM_IMA_WAV:

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

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

  120.             return -1;

  121.         }

  122.         break;

  123.     case CODEC_ID_ADPCM_IMA_WS:

  124.         if (avctx->extradata && avctx->extradata_size == 2 * 4) {

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

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

  127.         }

  128.         break;

  129.     default:

  130.         break;

  131.     }

  132.     avctx->sample_fmt = AV_SAMPLE_FMT_S16;

  133. 

  134.     avcodec_get_frame_defaults(&c->frame);

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

  136. 

  137.     return 0;

  138. }

  139. 

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

  141. {

  142.     int step_index;

  143.     int predictor;

  144.     int sign, delta, diff, step;

  145. 

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

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

  148.     if (step_index < 0) step_index = 0;

  149.     else if (step_index > 88) step_index = 88;

  150. 

  151.     sign = nibble & 8;

  152.     delta = nibble & 7;

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

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

  155.      * quickly enough */

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

  157.     predictor = c->predictor;

  158.     if (sign) predictor -= diff;

  159.     else predictor += diff;

  160. 

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

  162.     c->step_index = step_index;

  163. 

  164.     return (short)c->predictor;

  165. }

  166. 

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

  168. {

  169.     int step_index;

  170.     int predictor;

  171.     int diff, step;

  172. 

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

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

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

  176. 

  177.     diff = step >> 3;

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

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

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

  181. 

  182.     if (nibble & 8)

  183.         predictor = c->predictor - diff;

  184.     else

  185.         predictor = c->predictor + diff;

  186. 

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

  188.     c->step_index = step_index;

  189. 

  190.     return c->predictor;

  191. }

  192. 

  193. static inline short adpcm_ms_expand_nibble(ADPCMChannelStatus *c, char nibble)

  194. {

  195.     int predictor;

  196. 

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

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

  199. 

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

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

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

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

  204. 

  205.     return c->sample1;

  206. }

  207. 

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

  209. {

  210.     int sign, delta, diff;

  211.     int new_step;

  212. 

  213.     sign = nibble & 8;

  214.     delta = nibble & 7;

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

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

  217.      * quickly enough */

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

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

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

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

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

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

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

  225. 

  226.     return (short)c->predictor;

  227. }

  228. 

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

  230. {

  231.     int sign, delta, diff;

  232. 

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

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

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

  236. 

  237.     /* clamp result */

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

  239. 

  240.     /* calculate new step */

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

  242.         c->step++;

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

  244.         c->step--;

  245. 

  246.     return (short) c->predictor;

  247. }

  248. 

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

  250. {

  251.     if(!c->step) {

  252.         c->predictor = 0;

  253.         c->step = 127;

  254.     }

  255. 

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

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

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

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

  260.     return c->predictor;

  261. }

  262. 

  263. static int xa_decode(AVCodecContext *avctx,

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

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

  266. {

  267.     int i, j;

  268.     int shift,filter,f0,f1;

  269.     int s_1,s_2;

  270.     int d,s,t;

  271. 

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

  273. 

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

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

  276.         if (filter > 4) {

  277.             av_log(avctx, AV_LOG_ERROR,

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

  279.                    filter);

  280.             return AVERROR_INVALIDDATA;

  281.         }

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

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

  284. 

  285.         s_1 = left->sample1;

  286.         s_2 = left->sample2;

  287. 

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

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

  290. 

  291.             t = (signed char)(d<<4)>>4;

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

  293.             s_2 = s_1;

  294.             s_1 = av_clip_int16(s);

  295.             *out = s_1;

  296.             out += inc;

  297.         }

  298. 

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

  300.             left->sample1 = s_1;

  301.             left->sample2 = s_2;

  302.             s_1 = right->sample1;

  303.             s_2 = right->sample2;

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

  305.         }

  306. 

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

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

  309.         if (filter > 4) {

  310.             av_log(avctx, AV_LOG_ERROR,

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

  312.                    filter);

  313.             return AVERROR_INVALIDDATA;

  314.         }

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

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

  317. 

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

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

  320. 

  321.             t = (signed char)d >> 4;

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

  323.             s_2 = s_1;

  324.             s_1 = av_clip_int16(s);

  325.             *out = s_1;

  326.             out += inc;

  327.         }

  328. 

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

  330.             right->sample1 = s_1;

  331.             right->sample2 = s_2;

  332.             out -= 1;

  333.         } else {

  334.             left->sample1 = s_1;

  335.             left->sample2 = s_2;

  336.         }

  337.     }

  338. 

  339.     return 0;

  340. }

  341. 

  342. /**

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

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

  345.  * decode with the given buf_size.

  346.  *

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

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

  349.  *                           number of samples in each frame.

  350.  */

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

  352.                           int buf_size, int *coded_samples)

  353. {

  354.     ADPCMDecodeContext *s = avctx->priv_data;

  355.     int nb_samples        = 0;

  356.     int ch                = avctx->channels;

  357.     int has_coded_samples = 0;

  358.     int header_size;

  359. 

  360.     *coded_samples = 0;

  361. 

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

  363.     /* constant, only check buf_size */

  364.     case CODEC_ID_ADPCM_EA_XAS:

  365.         if (buf_size < 76 * ch)

  366.             return 0;

  367.         nb_samples = 128;

  368.         break;

  369.     case CODEC_ID_ADPCM_IMA_QT:

  370.         if (buf_size < 34 * ch)

  371.             return 0;

  372.         nb_samples = 64;

  373.         break;

  374.     /* simple 4-bit adpcm */

  375.     case CODEC_ID_ADPCM_CT:

  376.     case CODEC_ID_ADPCM_IMA_EA_SEAD:

  377.     case CODEC_ID_ADPCM_IMA_WS:

  378.     case CODEC_ID_ADPCM_YAMAHA:

  379.         nb_samples = buf_size * 2 / ch;

  380.         break;

  381.     }

  382.     if (nb_samples)

  383.         return nb_samples;

  384. 

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

  386.     header_size = 0;

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

  388.         case CODEC_ID_ADPCM_4XM:

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

  390.         case CODEC_ID_ADPCM_IMA_AMV:     header_size = 8;           break;

  391.         case CODEC_ID_ADPCM_IMA_SMJPEG:  header_size = 4;           break;

  392.     }

  393.     if (header_size > 0)

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

  395. 

  396.     /* more complex formats */

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

  398.     case CODEC_ID_ADPCM_EA:

  399.         has_coded_samples = 1;

  400.         if (buf_size < 4)

  401.             return 0;

  402.         *coded_samples  = AV_RL32(buf);

  403.         *coded_samples -= *coded_samples % 28;

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

  405.         break;

  406.     case CODEC_ID_ADPCM_IMA_EA_EACS:

  407.         has_coded_samples = 1;

  408.         if (buf_size < 4)

  409.             return 0;

  410.         *coded_samples = AV_RL32(buf);

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

  412.         break;

  413.     case CODEC_ID_ADPCM_EA_MAXIS_XA:

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

  415.         break;

  416.     case CODEC_ID_ADPCM_EA_R1:

  417.     case CODEC_ID_ADPCM_EA_R2:

  418.     case CODEC_ID_ADPCM_EA_R3:

  419.         /* maximum number of samples */

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

  421.         has_coded_samples = 1;

  422.         if (buf_size < 4)

  423.             return 0;

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

  425.         case CODEC_ID_ADPCM_EA_R1:

  426.             header_size    = 4 + 9 * ch;

  427.             *coded_samples = AV_RL32(buf);

  428.             break;

  429.         case CODEC_ID_ADPCM_EA_R2:

  430.             header_size    = 4 + 5 * ch;

  431.             *coded_samples = AV_RL32(buf);

  432.             break;

  433.         case CODEC_ID_ADPCM_EA_R3:

  434.             header_size    = 4 + 5 * ch;

  435.             *coded_samples = AV_RB32(buf);

  436.             break;

  437.         }

  438.         *coded_samples -= *coded_samples % 28;

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

  440.         nb_samples     -= nb_samples % 28;

  441.         break;

  442.     case CODEC_ID_ADPCM_IMA_DK3:

  443.         if (avctx->block_align > 0)

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

  445.         nb_samples = ((buf_size - 16) * 8 / 3) / ch;

  446.         break;

  447.     case CODEC_ID_ADPCM_IMA_DK4:

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

  449.         break;

  450.     case CODEC_ID_ADPCM_IMA_WAV:

  451.         if (avctx->block_align > 0)

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

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

  454.         break;

  455.     case CODEC_ID_ADPCM_MS:

  456.         if (avctx->block_align > 0)

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

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

  459.         break;

  460.     case CODEC_ID_ADPCM_SBPRO_2:

  461.     case CODEC_ID_ADPCM_SBPRO_3:

  462.     case CODEC_ID_ADPCM_SBPRO_4:

  463.     {

  464.         int samples_per_byte;

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

  466.         case CODEC_ID_ADPCM_SBPRO_2: samples_per_byte = 4; break;

  467.         case CODEC_ID_ADPCM_SBPRO_3: samples_per_byte = 3; break;

  468.         case CODEC_ID_ADPCM_SBPRO_4: samples_per_byte = 2; break;

  469.         }

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

  471.             nb_samples++;

  472.             buf_size -= ch;

  473.         }

  474.         nb_samples += buf_size * samples_per_byte / ch;

  475.         break;

  476.     }

  477.     case CODEC_ID_ADPCM_SWF:

  478.     {

  479.         int buf_bits       = buf_size * 8 - 2;

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

  481.         int block_hdr_size = 22 * ch;

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

  483.         int nblocks        = buf_bits / block_size;

  484.         int bits_left      = buf_bits - nblocks * block_size;

  485.         nb_samples         = nblocks * 4096;

  486.         if (bits_left >= block_hdr_size)

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

  488.         break;

  489.     }

  490.     case CODEC_ID_ADPCM_THP:

  491.         has_coded_samples = 1;

  492.         if (buf_size < 8)

  493.             return 0;

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

  495.         *coded_samples -= *coded_samples % 14;

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

  497.         break;

  498.     case CODEC_ID_ADPCM_XA:

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

  500.         break;

  501.     }

  502. 

  503.     /* validate coded sample count */

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

  505.         return AVERROR_INVALIDDATA;

  506. 

  507.     return nb_samples;

  508. }

  509. 

  510. /* DK3 ADPCM support macro */

  511. #define DK3_GET_NEXT_NIBBLE() \

  512.     if (decode_top_nibble_next) \

  513.     { \

  514.         nibble = last_byte >> 4; \

  515.         decode_top_nibble_next = 0; \

  516.     } \

  517.     else \

  518.     { \

  519.         if (end_of_packet) \

  520.             break; \

  521.         last_byte = *src++; \

  522.         if (src >= buf + buf_size) \

  523.             end_of_packet = 1; \

  524.         nibble = last_byte & 0x0F; \

  525.         decode_top_nibble_next = 1; \

  526.     }

  527. 

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

  529.                               int *got_frame_ptr, AVPacket *avpkt)

  530. {

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

  532.     int buf_size = avpkt->size;

  533.     ADPCMDecodeContext *c = avctx->priv_data;

  534.     ADPCMChannelStatus *cs;

  535.     int n, m, channel, i;

  536.     short *samples;

  537.     const uint8_t *src;

  538.     int st; /* stereo */

  539.     int count1, count2;

  540.     int nb_samples, coded_samples, ret;

  541. 

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

  543.     if (nb_samples <= 0) {

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

  545.         return AVERROR_INVALIDDATA;

  546.     }

  547. 

  548.     /* get output buffer */

  549.     c->frame.nb_samples = nb_samples;

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

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

  552.         return ret;

  553.     }

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

  555. 

  556.     /* use coded_samples when applicable */

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

  558.     if (coded_samples) {

  559.         if (coded_samples != nb_samples)

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

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

  562.     }

  563. 

  564.     src = buf;

  565. 

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

  567. 

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

  569.     case CODEC_ID_ADPCM_IMA_QT:

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

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

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

  573.             int16_t predictor;

  574.             int step_index;

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

  576.             /* (pppppp) (piiiiiii) */

  577. 

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

  579.             predictor = AV_RB16(src);

  580.             step_index = predictor & 0x7F;

  581.             predictor &= 0xFF80;

  582. 

  583.             src += 2;

  584. 

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

  586.                 int diff = (int)predictor - cs->predictor;

  587.                 if (diff < 0)

  588.                     diff = - diff;

  589.                 if (diff > 0x7f)

  590.                     goto update;

  591.             } else {

  592.             update:

  593.                 cs->step_index = step_index;

  594.                 cs->predictor = predictor;

  595.             }

  596. 

  597.             if (cs->step_index > 88){

  598.                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);

  599.                 cs->step_index = 88;

  600.             }

  601. 

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

  603. 

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

  605.                 *samples = adpcm_ima_qt_expand_nibble(cs, src[0] & 0x0F, 3);

  606.                 samples += avctx->channels;

  607.                 *samples = adpcm_ima_qt_expand_nibble(cs, src[0] >> 4  , 3);

  608.                 samples += avctx->channels;

  609.                 src ++;

  610.             }

  611.         }

  612.         break;

  613.     case CODEC_ID_ADPCM_IMA_WAV:

  614.         if (avctx->block_align != 0 && buf_size > avctx->block_align)

  615.             buf_size = avctx->block_align;

  616. 

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

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

  619.             cs->predictor = *samples++ = (int16_t)bytestream_get_le16(&src);

  620. 

  621.             cs->step_index = *src++;

  622.             if (cs->step_index > 88){

  623.                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);

  624.                 cs->step_index = 88;

  625.             }

  626.             if (*src++) av_log(avctx, AV_LOG_ERROR, "unused byte should be null but is %d!!\n", src[-1]); /* unused */

  627.         }

  628. 

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

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

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

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

  633.                     uint8_t v = *src++;

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

  635.                     samples += avctx->channels;

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

  637.                     samples += avctx->channels;

  638.                 }

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

  640.             }

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

  642.         }

  643.         break;

  644.     case CODEC_ID_ADPCM_4XM:

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

  646.             c->status[i].predictor= (int16_t)bytestream_get_le16(&src);

  647. 

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

  649.             c->status[i].step_index= (int16_t)bytestream_get_le16(&src);

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

  651.         }

  652. 

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

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

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

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

  657.                 uint8_t v = *src;

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

  659.                 samples += avctx->channels;

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

  661.                 samples += avctx->channels;

  662.             }

  663.         }

  664.         break;

  665.     case CODEC_ID_ADPCM_MS:

  666.     {

  667.         int block_predictor;

  668. 

  669.         if (avctx->block_align != 0 && buf_size > avctx->block_align)

  670.             buf_size = avctx->block_align;

  671. 

  672.         block_predictor = av_clip(*src++, 0, 6);

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

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

  675.         if (st) {

  676.             block_predictor = av_clip(*src++, 0, 6);

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

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

  679.         }

  680.         c->status[0].idelta = (int16_t)bytestream_get_le16(&src);

  681.         if (st){

  682.             c->status[1].idelta = (int16_t)bytestream_get_le16(&src);

  683.         }

  684. 

  685.         c->status[0].sample1 = bytestream_get_le16(&src);

  686.         if (st) c->status[1].sample1 = bytestream_get_le16(&src);

  687.         c->status[0].sample2 = bytestream_get_le16(&src);

  688.         if (st) c->status[1].sample2 = bytestream_get_le16(&src);

  689. 

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

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

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

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

  694.         for(n = (nb_samples - 2) >> (1 - st); n > 0; n--, src++) {

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

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

  697.         }

  698.         break;

  699.     }

  700.     case CODEC_ID_ADPCM_IMA_DK4:

  701.         if (avctx->block_align != 0 && buf_size > avctx->block_align)

  702.             buf_size = avctx->block_align;

  703. 

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

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

  706.             cs->predictor  = (int16_t)bytestream_get_le16(&src);

  707.             cs->step_index = av_clip(*src++, 0, 88);

  708.             src++;

  709.             *samples++ = cs->predictor;

  710.         }

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

  712.             uint8_t v = *src;

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

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

  715.         }

  716.         break;

  717.     case CODEC_ID_ADPCM_IMA_DK3:

  718.     {

  719.         unsigned char last_byte = 0;

  720.         unsigned char nibble;

  721.         int decode_top_nibble_next = 0;

  722.         int end_of_packet = 0;

  723.         int diff_channel;

  724. 

  725.         if (avctx->block_align != 0 && buf_size > avctx->block_align)

  726.             buf_size = avctx->block_align;

  727. 

  728.         c->status[0].predictor  = (int16_t)AV_RL16(src + 10);

  729.         c->status[1].predictor  = (int16_t)AV_RL16(src + 12);

  730.         c->status[0].step_index = av_clip(src[14], 0, 88);

  731.         c->status[1].step_index = av_clip(src[15], 0, 88);

  732.         /* sign extend the predictors */

  733.         src += 16;

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

  735. 

  736.         /* the DK3_GET_NEXT_NIBBLE macro issues the break statement when

  737.          * the buffer is consumed */

  738.         while (1) {

  739. 

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

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

  742. 

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

  744.             DK3_GET_NEXT_NIBBLE();

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

  746. 

  747.             /* process the diff channel predictor */

  748.             DK3_GET_NEXT_NIBBLE();

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

  750. 

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

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

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

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

  755. 

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

  757.             DK3_GET_NEXT_NIBBLE();

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

  759. 

  760.             /* process the second 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.         break;

  766.     }

  767.     case CODEC_ID_ADPCM_IMA_ISS:

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

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

  770.             cs->predictor  = (int16_t)bytestream_get_le16(&src);

  771.             cs->step_index = av_clip(*src++, 0, 88);

  772.             src++;

  773.         }

  774. 

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

  776.             uint8_t v1, v2;

  777.             uint8_t v = *src;

  778.             /* nibbles are swapped for mono */

  779.             if (st) {

  780.                 v1 = v >> 4;

  781.                 v2 = v & 0x0F;

  782.             } else {

  783.                 v2 = v >> 4;

  784.                 v1 = v & 0x0F;

  785.             }

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

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

  788.         }

  789.         break;

  790.     case CODEC_ID_ADPCM_IMA_WS:

  791.         while (src < buf + buf_size) {

  792.             uint8_t v = *src++;

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

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

  795.         }

  796.         break;

  797.     case CODEC_ID_ADPCM_XA:

  798.         while (buf_size >= 128) {

  799.             if ((ret = xa_decode(avctx, samples, src, &c->status[0],

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

  801.                 return ret;

  802.             src += 128;

  803.             samples += 28 * 8;

  804.             buf_size -= 128;

  805.         }

  806.         break;

  807.     case CODEC_ID_ADPCM_IMA_EA_EACS:

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

  809. 

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

  811.             c->status[i].step_index = av_clip(bytestream_get_le32(&src), 0, 88);

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

  813.             c->status[i].predictor  = bytestream_get_le32(&src);

  814. 

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

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

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

  818.         }

  819.         break;

  820.     case CODEC_ID_ADPCM_IMA_EA_SEAD:

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

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

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

  824.         }

  825.         break;

  826.     case CODEC_ID_ADPCM_EA:

  827.     {

  828.         int32_t previous_left_sample, previous_right_sample;

  829.         int32_t current_left_sample, current_right_sample;

  830.         int32_t next_left_sample, next_right_sample;

  831.         int32_t coeff1l, coeff2l, coeff1r, coeff2r;

  832.         uint8_t shift_left, shift_right;

  833. 

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

  835.            each coding 28 stereo samples. */

  836. 

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

  838. 

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

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

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

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

  843. 

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

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

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

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

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

  849.             src++;

  850. 

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

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

  853.             src++;

  854. 

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

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

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

  858.                 src++;

  859. 

  860.                 next_left_sample = (next_left_sample +

  861.                     (current_left_sample * coeff1l) +

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

  863.                 next_right_sample = (next_right_sample +

  864.                     (current_right_sample * coeff1r) +

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

  866. 

  867.                 previous_left_sample = current_left_sample;

  868.                 current_left_sample = av_clip_int16(next_left_sample);

  869.                 previous_right_sample = current_right_sample;

  870.                 current_right_sample = av_clip_int16(next_right_sample);

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

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

  873.             }

  874.         }

  875. 

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

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

  878. 

  879.         break;

  880.     }

  881.     case CODEC_ID_ADPCM_EA_MAXIS_XA:

  882.     {

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

  884. 

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

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

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

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

  889.             src++;

  890.         }

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

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

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

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

  895.                     sample = (sample +

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

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

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

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

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

  901.                 }

  902.             }

  903.             src+=avctx->channels;

  904.         }

  905.         /* consume whole packet */

  906.         src = buf + buf_size;

  907.         break;

  908.     }

  909.     case CODEC_ID_ADPCM_EA_R1:

  910.     case CODEC_ID_ADPCM_EA_R2:

  911.     case CODEC_ID_ADPCM_EA_R3: {

  912.         /* channel numbering

  913.            2chan: 0=fl, 1=fr

  914.            4chan: 0=fl, 1=rl, 2=fr, 3=rr

  915.            6chan: 0=fl, 1=c,  2=fr, 3=rl,  4=rr, 5=sub */

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

  917.         int32_t previous_sample, current_sample, next_sample;

  918.         int32_t coeff1, coeff2;

  919.         uint8_t shift;

  920.         unsigned int channel;

  921.         uint16_t *samplesC;

  922.         const uint8_t *srcC;

  923.         const uint8_t *src_end = buf + buf_size;

  924.         int count = 0;

  925. 

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

  927. 

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

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

  930.                                          : bytestream_get_le32(&src))

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

  932. 

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

  934.             srcC  = src + offset;

  935.             samplesC = samples + channel;

  936. 

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

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

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

  940.             } else {

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

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

  943.             }

  944. 

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

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

  947.                     srcC++;

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

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

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

  951. 

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

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

  954.                         samplesC += avctx->channels;

  955.                     }

  956.                 } else {

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

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

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

  960. 

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

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

  963.                         if (count2 & 1)

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

  965.                         else

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

  967. 

  968.                         next_sample += (current_sample  * coeff1) +

  969.                                        (previous_sample * coeff2);

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

  971. 

  972.                         previous_sample = current_sample;

  973.                         current_sample  = next_sample;

  974.                         *samplesC = current_sample;

  975.                         samplesC += avctx->channels;

  976.                     }

  977.                 }

  978.             }

  979.             if (!count) {

  980.                 count = count1;

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

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

  983.                 count = FFMAX(count, count1);

  984.             }

  985. 

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

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

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

  989.             }

  990.         }

  991. 

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

  993.         src = src_end;

  994.         break;

  995.     }

  996.     case CODEC_ID_ADPCM_EA_XAS:

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

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

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

  1000.             for (n=0; n<4; n++, s+=32*avctx->channels) {

  1001.                 for (i=0; i<2; i++)

  1002.                     coeff[i][n] = ea_adpcm_table[(src[0]&0x0F)+4*i];

  1003.                 shift[n] = 20 - (src[2] & 0x0F);

  1004.                 for (s2=s, i=0; i<2; i++, src+=2, s2+=avctx->channels)

  1005.                     s2[0] = (src[0]&0xF0) + (src[1]<<8);

  1006.             }

  1007. 

  1008.             for (m=2; m<32; m+=2) {

  1009.                 s = &samples[m*avctx->channels + channel];

  1010.                 for (n=0; n<4; n++, src++, s+=32*avctx->channels) {

  1011.                     for (s2=s, i=0; i<8; i+=4, s2+=avctx->channels) {

  1012.                         int level = sign_extend(*src >> (4 - i), 4) << shift[n];

  1013.                         int pred  = s2[-1*avctx->channels] * coeff[0][n]

  1014.                                   + s2[-2*avctx->channels] * coeff[1][n];

  1015.                         s2[0] = av_clip_int16((level + pred + 0x80) >> 8);

  1016.                     }

  1017.                 }

  1018.             }

  1019.         }

  1020.         break;

  1021.     case CODEC_ID_ADPCM_IMA_AMV:

  1022.     case CODEC_ID_ADPCM_IMA_SMJPEG:

  1023.         if (avctx->codec->id == CODEC_ID_ADPCM_IMA_AMV) {

  1024.             c->status[0].predictor = sign_extend(bytestream_get_le16(&src), 16);

  1025.             c->status[0].step_index = av_clip(bytestream_get_le16(&src), 0, 88);

  1026.             src += 4;

  1027.         } else {

  1028.             c->status[0].predictor = sign_extend(bytestream_get_be16(&src), 16);

  1029.             c->status[0].step_index = av_clip(bytestream_get_byte(&src), 0, 88);

  1030.             src += 1;

  1031.         }

  1032. 

  1033.         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {

  1034.             char hi, lo;

  1035.             lo = *src & 0x0F;

  1036.             hi = *src >> 4;

  1037. 

  1038.             if (avctx->codec->id == CODEC_ID_ADPCM_IMA_AMV)

  1039.                 FFSWAP(char, hi, lo);

  1040. 

  1041.             *samples++ = adpcm_ima_expand_nibble(&c->status[0],

  1042.                 lo, 3);

  1043.             *samples++ = adpcm_ima_expand_nibble(&c->status[0],

  1044.                 hi, 3);

  1045.         }

  1046.         break;

  1047.     case CODEC_ID_ADPCM_CT:

  1048.         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {

  1049.             uint8_t v = *src;

  1050.             *samples++ = adpcm_ct_expand_nibble(&c->status[0 ], v >> 4  );

  1051.             *samples++ = adpcm_ct_expand_nibble(&c->status[st], v & 0x0F);

  1052.         }

  1053.         break;

  1054.     case CODEC_ID_ADPCM_SBPRO_4:

  1055.     case CODEC_ID_ADPCM_SBPRO_3:

  1056.     case CODEC_ID_ADPCM_SBPRO_2:

  1057.         if (!c->status[0].step_index) {

  1058.             /* the first byte is a raw sample */

  1059.             *samples++ = 128 * (*src++ - 0x80);

  1060.             if (st)

  1061.               *samples++ = 128 * (*src++ - 0x80);

  1062.             c->status[0].step_index = 1;

  1063.             nb_samples--;

  1064.         }

  1065.         if (avctx->codec->id == CODEC_ID_ADPCM_SBPRO_4) {

  1066.             for (n = nb_samples >> (1 - st); n > 0; n--, src++) {

  1067.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1068.                     src[0] >> 4, 4, 0);

  1069.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],

  1070.                     src[0] & 0x0F, 4, 0);

  1071.             }

  1072.         } else if (avctx->codec->id == CODEC_ID_ADPCM_SBPRO_3) {

  1073.             for (n = nb_samples / 3; n > 0; n--, src++) {

  1074.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1075.                      src[0] >> 5        , 3, 0);

  1076.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1077.                     (src[0] >> 2) & 0x07, 3, 0);

  1078.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1079.                     src[0] & 0x03, 2, 0);

  1080.             }

  1081.         } else {

  1082.             for (n = nb_samples >> (2 - st); n > 0; n--, src++) {

  1083.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1084.                      src[0] >> 6        , 2, 2);

  1085.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],

  1086.                     (src[0] >> 4) & 0x03, 2, 2);

  1087.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],

  1088.                     (src[0] >> 2) & 0x03, 2, 2);

  1089.                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],

  1090.                     src[0] & 0x03, 2, 2);

  1091.             }

  1092.         }

  1093.         break;

  1094.     case CODEC_ID_ADPCM_SWF:

  1095.     {

  1096.         GetBitContext gb;

  1097.         const int *table;

  1098.         int k0, signmask, nb_bits, count;

  1099.         int size = buf_size*8;

  1100. 

  1101.         init_get_bits(&gb, buf, size);

  1102. 

  1103.         //read bits & initial values

  1104.         nb_bits = get_bits(&gb, 2)+2;

  1105.         //av_log(NULL,AV_LOG_INFO,"nb_bits: %d\n", nb_bits);

  1106.         table = swf_index_tables[nb_bits-2];

  1107.         k0 = 1 << (nb_bits-2);

  1108.         signmask = 1 << (nb_bits-1);

  1109. 

  1110.         while (get_bits_count(&gb) <= size - 22*avctx->channels) {

  1111.             for (i = 0; i < avctx->channels; i++) {

  1112.                 *samples++ = c->status[i].predictor = get_sbits(&gb, 16);

  1113.                 c->status[i].step_index = get_bits(&gb, 6);

  1114.             }

  1115. 

  1116.             for (count = 0; get_bits_count(&gb) <= size - nb_bits*avctx->channels && count < 4095; count++) {

  1117.                 int i;

  1118. 

  1119.                 for (i = 0; i < avctx->channels; i++) {

  1120.                     // similar to IMA adpcm

  1121.                     int delta = get_bits(&gb, nb_bits);

  1122.                     int step = ff_adpcm_step_table[c->status[i].step_index];

  1123.                     long vpdiff = 0; // vpdiff = (delta+0.5)*step/4

  1124.                     int k = k0;

  1125. 

  1126.                     do {

  1127.                         if (delta & k)

  1128.                             vpdiff += step;

  1129.                         step >>= 1;

  1130.                         k >>= 1;

  1131.                     } while(k);

  1132.                     vpdiff += step;

  1133. 

  1134.                     if (delta & signmask)

  1135.                         c->status[i].predictor -= vpdiff;

  1136.                     else

  1137.                         c->status[i].predictor += vpdiff;

  1138. 

  1139.                     c->status[i].step_index += table[delta & (~signmask)];

  1140. 

  1141.                     c->status[i].step_index = av_clip(c->status[i].step_index, 0, 88);

  1142.                     c->status[i].predictor = av_clip_int16(c->status[i].predictor);

  1143. 

  1144.                     *samples++ = c->status[i].predictor;

  1145.                 }

  1146.             }

  1147.         }

  1148.         src += buf_size;

  1149.         break;

  1150.     }

  1151.     case CODEC_ID_ADPCM_YAMAHA:

  1152.         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {

  1153.             uint8_t v = *src;

  1154.             *samples++ = adpcm_yamaha_expand_nibble(&c->status[0 ], v & 0x0F);

  1155.             *samples++ = adpcm_yamaha_expand_nibble(&c->status[st], v >> 4  );

  1156.         }

  1157.         break;

  1158.     case CODEC_ID_ADPCM_THP:

  1159.     {

  1160.         int table[2][16];

  1161.         int prev[2][2];

  1162.         int ch;

  1163. 

  1164.         src += 4; // skip channel size

  1165.         src += 4; // skip number of samples (already read)

  1166. 

  1167.         for (i = 0; i < 32; i++)

  1168.             table[0][i] = (int16_t)bytestream_get_be16(&src);

  1169. 

  1170.         /* Initialize the previous sample.  */

  1171.         for (i = 0; i < 4; i++)

  1172.             prev[0][i] = (int16_t)bytestream_get_be16(&src);

  1173. 

  1174.         for (ch = 0; ch <= st; ch++) {

  1175.             samples = (short *)c->frame.data[0] + ch;

  1176. 

  1177.             /* Read in every sample for this channel.  */

  1178.             for (i = 0; i < nb_samples / 14; i++) {

  1179.                 int index = (*src >> 4) & 7;

  1180.                 unsigned int exp = *src++ & 15;

  1181.                 int factor1 = table[ch][index * 2];

  1182.                 int factor2 = table[ch][index * 2 + 1];

  1183. 

  1184.                 /* Decode 14 samples.  */

  1185.                 for (n = 0; n < 14; n++) {

  1186.                     int32_t sampledat;

  1187.                     if(n&1) sampledat = sign_extend(*src++, 4);

  1188.                     else    sampledat = sign_extend(*src >> 4, 4);

  1189. 

  1190.                     sampledat = ((prev[ch][0]*factor1

  1191.                                 + prev[ch][1]*factor2) >> 11) + (sampledat << exp);

  1192.                     *samples = av_clip_int16(sampledat);

  1193.                     prev[ch][1] = prev[ch][0];

  1194.                     prev[ch][0] = *samples++;

  1195. 

  1196.                     /* In case of stereo, skip one sample, this sample

  1197.                        is for the other channel.  */

  1198.                     samples += st;

  1199.                 }

  1200.             }

  1201.         }

  1202.         break;

  1203.     }

  1204. 

  1205.     default:

  1206.         return -1;

  1207.     }

  1208. 

  1209.     *got_frame_ptr   = 1;

  1210.     *(AVFrame *)data = c->frame;

  1211. 

  1212.     return src - buf;

  1213. }

  1214. 

  1215. 

  1216. #define ADPCM_DECODER(id_, name_, long_name_)               \

  1217. AVCodec ff_ ## name_ ## _decoder = {                        \

  1218.     .name           = #name_,                               \

  1219.     .type           = AVMEDIA_TYPE_AUDIO,                   \

  1220.     .id             = id_,                                  \

  1221.     .priv_data_size = sizeof(ADPCMDecodeContext),           \

  1222.     .init           = adpcm_decode_init,                    \

  1223.     .decode         = adpcm_decode_frame,                   \

  1224.     .capabilities   = CODEC_CAP_DR1,                        \

  1225.     .long_name      = NULL_IF_CONFIG_SMALL(long_name_),     \

  1226. }

  1227. 

  1228. /* Note: Do not forget to add new entries to the Makefile as well. */

  1229. ADPCM_DECODER(CODEC_ID_ADPCM_4XM, adpcm_4xm, "ADPCM 4X Movie");

  1230. ADPCM_DECODER(CODEC_ID_ADPCM_CT, adpcm_ct, "ADPCM Creative Technology");

  1231. ADPCM_DECODER(CODEC_ID_ADPCM_EA, adpcm_ea, "ADPCM Electronic Arts");

  1232. ADPCM_DECODER(CODEC_ID_ADPCM_EA_MAXIS_XA, adpcm_ea_maxis_xa, "ADPCM Electronic Arts Maxis CDROM XA");

  1233. ADPCM_DECODER(CODEC_ID_ADPCM_EA_R1, adpcm_ea_r1, "ADPCM Electronic Arts R1");

  1234. ADPCM_DECODER(CODEC_ID_ADPCM_EA_R2, adpcm_ea_r2, "ADPCM Electronic Arts R2");

  1235. ADPCM_DECODER(CODEC_ID_ADPCM_EA_R3, adpcm_ea_r3, "ADPCM Electronic Arts R3");

  1236. ADPCM_DECODER(CODEC_ID_ADPCM_EA_XAS, adpcm_ea_xas, "ADPCM Electronic Arts XAS");

  1237. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_AMV, adpcm_ima_amv, "ADPCM IMA AMV");

  1238. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_DK3, adpcm_ima_dk3, "ADPCM IMA Duck DK3");

  1239. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_DK4, adpcm_ima_dk4, "ADPCM IMA Duck DK4");

  1240. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_EA_EACS, adpcm_ima_ea_eacs, "ADPCM IMA Electronic Arts EACS");

  1241. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_EA_SEAD, adpcm_ima_ea_sead, "ADPCM IMA Electronic Arts SEAD");

  1242. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_ISS, adpcm_ima_iss, "ADPCM IMA Funcom ISS");

  1243. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt, "ADPCM IMA QuickTime");

  1244. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_SMJPEG, adpcm_ima_smjpeg, "ADPCM IMA Loki SDL MJPEG");

  1245. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav, "ADPCM IMA WAV");

  1246. ADPCM_DECODER(CODEC_ID_ADPCM_IMA_WS, adpcm_ima_ws, "ADPCM IMA Westwood");

  1247. ADPCM_DECODER(CODEC_ID_ADPCM_MS, adpcm_ms, "ADPCM Microsoft");

  1248. ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_2, adpcm_sbpro_2, "ADPCM Sound Blaster Pro 2-bit");

  1249. ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_3, adpcm_sbpro_3, "ADPCM Sound Blaster Pro 2.6-bit");

  1250. ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_4, adpcm_sbpro_4, "ADPCM Sound Blaster Pro 4-bit");

  1251. ADPCM_DECODER(CODEC_ID_ADPCM_SWF, adpcm_swf, "ADPCM Shockwave Flash");

  1252. ADPCM_DECODER(CODEC_ID_ADPCM_THP, adpcm_thp, "ADPCM Nintendo Gamecube THP");

  1253. ADPCM_DECODER(CODEC_ID_ADPCM_XA, adpcm_xa, "ADPCM CDROM XA");

  1254. ADPCM_DECODER(CODEC_ID_ADPCM_YAMAHA, adpcm_yamaha, "ADPCM Yamaha");