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FFmpeg/libavcodec/adpcm.c

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  1. /*

  2.  * ADPCM codecs

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

  4.  *

  5.  * This library is free software; you can redistribute it and/or

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

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

  8.  * version 2 of the License, or (at your option) any later version.

  9.  *

  10.  * This library is distributed in the hope that it will be useful,

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

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

  13.  * Lesser General Public License for more details.

  14.  *

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

  16.  * License along with this library; if not, write to the Free Software

  17.  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

  18.  */

  19. #include "avcodec.h"

  20. 

  21. /**

  22.  * @file adpcm.c

  23.  * ADPCM codecs.

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

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

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

  27.  * CD-ROM XA ADPCM codec by BERO

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

  29.  *

  30.  * Features and limitations:

  31.  *

  32.  * Reference documents:

  33.  * http://www.pcisys.net/~melanson/codecs/simpleaudio.html

  34.  * http://www.geocities.com/SiliconValley/8682/aud3.txt

  35.  * http://openquicktime.sourceforge.net/plugins.htm

  36.  * XAnim sources (xa_codec.c) http://www.rasnaimaging.com/people/lapus/download.html

  37.  * http://www.cs.ucla.edu/~leec/mediabench/applications.html

  38.  * SoX source code http://home.sprynet.com/~cbagwell/sox.html

  39.  *

  40.  * CD-ROM XA:

  41.  * http://ku-www.ss.titech.ac.jp/~yatsushi/xaadpcm.html

  42.  * vagpack & depack http://homepages.compuserve.de/bITmASTER32/psx-index.html

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

  44.  */

  45. 

  46. #define BLKSIZE 1024

  47. 

  48. #define CLAMP_TO_SHORT(value) \

  49. if (value > 32767) \

  50.     value = 32767; \

  51. else if (value < -32768) \

  52.     value = -32768; \

  53. 

  54. /* step_table[] and index_table[] are from the ADPCM reference source */

  55. /* This is the index table: */

  56. static const int index_table[16] = {

  57.     -1, -1, -1, -1, 2, 4, 6, 8,

  58.     -1, -1, -1, -1, 2, 4, 6, 8,

  59. };

  60. 

  61. /** 

  62.  * This is the step table. Note that many programs use slight deviations from

  63.  * this table, but such deviations are negligible:

  64.  */

  65. static const int step_table[89] = {

  66.     7, 8, 9, 10, 11, 12, 13, 14, 16, 17,

  67.     19, 21, 23, 25, 28, 31, 34, 37, 41, 45,

  68.     50, 55, 60, 66, 73, 80, 88, 97, 107, 118,

  69.     130, 143, 157, 173, 190, 209, 230, 253, 279, 307,

  70.     337, 371, 408, 449, 494, 544, 598, 658, 724, 796,

  71.     876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,

  72.     2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,

  73.     5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,

  74.     15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767

  75. };

  76. 

  77. /* These are for MS-ADPCM */

  78. /* AdaptationTable[], AdaptCoeff1[], and AdaptCoeff2[] are from libsndfile */

  79. static const int AdaptationTable[] = {

  80.         230, 230, 230, 230, 307, 409, 512, 614,

  81.         768, 614, 512, 409, 307, 230, 230, 230

  82. };

  83. 

  84. static const int AdaptCoeff1[] = {

  85.         256, 512, 0, 192, 240, 460, 392

  86. };

  87. 

  88. static const int AdaptCoeff2[] = {

  89.         0, -256, 0, 64, 0, -208, -232

  90. };

  91. 

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

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

  94.    {   0,   0 },

  95.    {  60,   0 },

  96.    { 115, -52 },

  97.    {  98, -55 },

  98.    { 122, -60 }

  99. };

  100. 

  101. static int ea_adpcm_table[] = {

  102.     0, 240, 460, 392, 0, 0, -208, -220, 0, 1,

  103.     3, 4, 7, 8, 10, 11, 0, -1, -3, -4

  104. };

  105. 

  106. /* end of tables */

  107. 

  108. typedef struct ADPCMChannelStatus {

  109.     int predictor;

  110.     short int step_index;

  111.     int step;

  112.     /* for encoding */

  113.     int prev_sample;

  114. 

  115.     /* MS version */

  116.     short sample1;

  117.     short sample2;

  118.     int coeff1;

  119.     int coeff2;

  120.     int idelta;

  121. } ADPCMChannelStatus;

  122. 

  123. typedef struct ADPCMContext {

  124.     int channel; /* for stereo MOVs, decode left, then decode right, then tell it's decoded */

  125.     ADPCMChannelStatus status[2];

  126.     short sample_buffer[32]; /* hold left samples while waiting for right samples */

  127. } ADPCMContext;

  128. 

  129. /* XXX: implement encoding */

  130. 

  131. #ifdef CONFIG_ENCODERS

  132. static int adpcm_encode_init(AVCodecContext *avctx)

  133. {

  134.     if (avctx->channels > 2)

  135.         return -1; /* only stereo or mono =) */

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

  137.     case CODEC_ID_ADPCM_IMA_QT:

  138.         av_log(avctx, AV_LOG_ERROR, "ADPCM: codec adpcm_ima_qt unsupported for encoding !\n");

  139.         avctx->frame_size = 64; /* XXX: can multiple of avctx->channels * 64 (left and right blocks are interleaved) */

  140.         return -1;

  141.         break;

  142.     case CODEC_ID_ADPCM_IMA_WAV:

  143.         avctx->frame_size = (BLKSIZE - 4 * avctx->channels) * 8 / (4 * avctx->channels) + 1; /* each 16 bits sample gives one nibble */

  144.                                                              /* and we have 4 bytes per channel overhead */

  145.         avctx->block_align = BLKSIZE;

  146.         /* seems frame_size isn't taken into account... have to buffer the samples :-( */

  147.         break;

  148.     case CODEC_ID_ADPCM_MS:

  149.         avctx->frame_size = (BLKSIZE - 7 * avctx->channels) * 2 / avctx->channels + 2; /* each 16 bits sample gives one nibble */

  150.                                                              /* and we have 7 bytes per channel overhead */

  151.         avctx->block_align = BLKSIZE;

  152.         break;

  153.     default:

  154.         return -1;

  155.         break;

  156.     }

  157. 

  158.     avctx->coded_frame= avcodec_alloc_frame();

  159.     avctx->coded_frame->key_frame= 1;

  160. 

  161.     return 0;

  162. }

  163. 

  164. static int adpcm_encode_close(AVCodecContext *avctx)

  165. {

  166.     av_freep(&avctx->coded_frame);

  167. 

  168.     return 0;

  169. }

  170. 

  171. 

  172. static inline unsigned char adpcm_ima_compress_sample(ADPCMChannelStatus *c, short sample)

  173. {

  174.     int step_index;

  175.     unsigned char nibble;

  176.     

  177.     int sign = 0; /* sign bit of the nibble (MSB) */

  178.     int delta, predicted_delta;

  179. 

  180.     delta = sample - c->prev_sample;

  181. 

  182.     if (delta < 0) {

  183.         sign = 1;

  184.         delta = -delta;

  185.     }

  186. 

  187.     step_index = c->step_index;

  188. 

  189.     /* nibble = 4 * delta / step_table[step_index]; */

  190.     nibble = (delta << 2) / step_table[step_index];

  191. 

  192.     if (nibble > 7)

  193.         nibble = 7;

  194. 

  195.     step_index += index_table[nibble];

  196.     if (step_index < 0)

  197.         step_index = 0;

  198.     if (step_index > 88)

  199.         step_index = 88;

  200. 

  201.     /* what the decoder will find */

  202.     predicted_delta = ((step_table[step_index] * nibble) / 4) + (step_table[step_index] / 8);

  203. 

  204.     if (sign)

  205.         c->prev_sample -= predicted_delta;

  206.     else

  207.         c->prev_sample += predicted_delta;

  208. 

  209.     CLAMP_TO_SHORT(c->prev_sample);

  210. 

  211. 

  212.     nibble += sign << 3; /* sign * 8 */   

  213. 

  214.     /* save back */

  215.     c->step_index = step_index;

  216. 

  217.     return nibble;

  218. }

  219. 

  220. static inline unsigned char adpcm_ms_compress_sample(ADPCMChannelStatus *c, short sample)

  221. {

  222.     int predictor, nibble, bias;

  223. 

  224.     predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 256;

  225.     

  226.     nibble= sample - predictor;

  227.     if(nibble>=0) bias= c->idelta/2;

  228.     else          bias=-c->idelta/2;

  229.         

  230.     nibble= (nibble + bias) / c->idelta;

  231.     nibble= clip(nibble, -8, 7)&0x0F;

  232.     

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

  234.     CLAMP_TO_SHORT(predictor);

  235. 

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

  237.     c->sample1 = predictor;

  238. 

  239.     c->idelta = (AdaptationTable[(int)nibble] * c->idelta) >> 8;

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

  241. 

  242.     return nibble;

  243. }

  244. 

  245. static int adpcm_encode_frame(AVCodecContext *avctx,

  246. 			    unsigned char *frame, int buf_size, void *data)

  247. {

  248.     int n, i, st;

  249.     short *samples;

  250.     unsigned char *dst;

  251.     ADPCMContext *c = avctx->priv_data;

  252. 

  253.     dst = frame;

  254.     samples = (short *)data;

  255.     st= avctx->channels == 2;

  256. /*    n = (BLKSIZE - 4 * avctx->channels) / (2 * 8 * avctx->channels); */

  257. 

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

  259.     case CODEC_ID_ADPCM_IMA_QT: /* XXX: can't test until we get .mov writer */

  260.         break;

  261.     case CODEC_ID_ADPCM_IMA_WAV:

  262.         n = avctx->frame_size / 8;

  263.             c->status[0].prev_sample = (signed short)samples[0]; /* XXX */

  264. /*            c->status[0].step_index = 0; *//* XXX: not sure how to init the state machine */

  265.             *dst++ = (c->status[0].prev_sample) & 0xFF; /* little endian */

  266.             *dst++ = (c->status[0].prev_sample >> 8) & 0xFF;

  267.             *dst++ = (unsigned char)c->status[0].step_index;

  268.             *dst++ = 0; /* unknown */

  269.             samples++;

  270.             if (avctx->channels == 2) {

  271.                 c->status[1].prev_sample = (signed short)samples[1];

  272. /*                c->status[1].step_index = 0; */

  273.                 *dst++ = (c->status[1].prev_sample) & 0xFF;

  274.                 *dst++ = (c->status[1].prev_sample >> 8) & 0xFF;

  275.                 *dst++ = (unsigned char)c->status[1].step_index;

  276.                 *dst++ = 0;

  277.                 samples++;

  278.             }

  279.         

  280.             /* stereo: 4 bytes (8 samples) for left, 4 bytes for right, 4 bytes left, ... */

  281.             for (; n>0; n--) {

  282.                 *dst = adpcm_ima_compress_sample(&c->status[0], samples[0]) & 0x0F;

  283.                 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels]) << 4) & 0xF0;

  284.                 dst++;

  285.                 *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 2]) & 0x0F;

  286.                 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 3]) << 4) & 0xF0;

  287.                 dst++;

  288.                 *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 4]) & 0x0F;

  289.                 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 5]) << 4) & 0xF0;

  290.                 dst++;

  291.                 *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 6]) & 0x0F;

  292.                 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 7]) << 4) & 0xF0;

  293.                 dst++;

  294.                 /* right channel */

  295.                 if (avctx->channels == 2) {

  296.                     *dst = adpcm_ima_compress_sample(&c->status[1], samples[1]);

  297.                     *dst |= adpcm_ima_compress_sample(&c->status[1], samples[3]) << 4;

  298.                     dst++;

  299.                     *dst = adpcm_ima_compress_sample(&c->status[1], samples[5]);

  300.                     *dst |= adpcm_ima_compress_sample(&c->status[1], samples[7]) << 4;

  301.                     dst++;

  302.                     *dst = adpcm_ima_compress_sample(&c->status[1], samples[9]);

  303.                     *dst |= adpcm_ima_compress_sample(&c->status[1], samples[11]) << 4;

  304.                     dst++;

  305.                     *dst = adpcm_ima_compress_sample(&c->status[1], samples[13]);

  306.                     *dst |= adpcm_ima_compress_sample(&c->status[1], samples[15]) << 4;

  307.                     dst++;

  308.                 }

  309.                 samples += 8 * avctx->channels;

  310.             }

  311.         break;

  312.     case CODEC_ID_ADPCM_MS:

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

  314.             int predictor=0;

  315. 

  316.             *dst++ = predictor;

  317.             c->status[i].coeff1 = AdaptCoeff1[predictor];

  318.             c->status[i].coeff2 = AdaptCoeff2[predictor];

  319.         }

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

  321.             if (c->status[i].idelta < 16) 

  322.                 c->status[i].idelta = 16;

  323.             

  324.             *dst++ = c->status[i].idelta & 0xFF;

  325.             *dst++ = c->status[i].idelta >> 8;

  326.         }

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

  328.             c->status[i].sample1= *samples++;

  329. 

  330.             *dst++ = c->status[i].sample1 & 0xFF;

  331.             *dst++ = c->status[i].sample1 >> 8;

  332.         }

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

  334.             c->status[i].sample2= *samples++;

  335. 

  336.             *dst++ = c->status[i].sample2 & 0xFF;

  337.             *dst++ = c->status[i].sample2 >> 8;

  338.         }

  339. 

  340.         for(i=7*avctx->channels; i<avctx->block_align; i++) {

  341.             int nibble;

  342.             nibble = adpcm_ms_compress_sample(&c->status[ 0], *samples++)<<4;

  343.             nibble|= adpcm_ms_compress_sample(&c->status[st], *samples++);

  344.             *dst++ = nibble;

  345.         }

  346.         break;

  347.     default:

  348.         return -1;

  349.     }

  350.     return dst - frame;

  351. }

  352. #endif //CONFIG_ENCODERS

  353. 

  354. static int adpcm_decode_init(AVCodecContext * avctx)

  355. {

  356.     ADPCMContext *c = avctx->priv_data;

  357. 

  358.     c->channel = 0;

  359.     c->status[0].predictor = c->status[1].predictor = 0;

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

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

  362. 

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

  364.     default:

  365.         break;

  366.     }

  367.     return 0;

  368. }

  369. 

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

  371. {

  372.     int step_index;

  373.     int predictor;

  374.     int sign, delta, diff, step;

  375. 

  376.     step = step_table[c->step_index];

  377.     step_index = c->step_index + index_table[(unsigned)nibble];

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

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

  380. 

  381.     sign = nibble & 8;

  382.     delta = nibble & 7;

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

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

  385.      * quickly enough */

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

  387.     predictor = c->predictor;

  388.     if (sign) predictor -= diff;

  389.     else predictor += diff;

  390. 

  391.     CLAMP_TO_SHORT(predictor);

  392.     c->predictor = predictor;

  393.     c->step_index = step_index;

  394. 

  395.     return (short)predictor;

  396. }

  397. 

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

  399. {

  400.     int predictor;

  401. 

  402.     predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 256;

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

  404.     CLAMP_TO_SHORT(predictor);

  405. 

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

  407.     c->sample1 = predictor;

  408.     c->idelta = (AdaptationTable[(int)nibble] * c->idelta) >> 8;

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

  410. 

  411.     return (short)predictor;

  412. }

  413. 

  414. static void xa_decode(short *out, const unsigned char *in, 

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

  416. {

  417.     int i, j;

  418.     int shift,filter,f0,f1;

  419.     int s_1,s_2;

  420.     int d,s,t;

  421. 

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

  423. 

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

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

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

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

  428. 

  429.         s_1 = left->sample1;

  430.         s_2 = left->sample2;

  431. 

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

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

  434. 

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

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

  437.             CLAMP_TO_SHORT(s);

  438.             *out = s;

  439.             out += inc;

  440.             s_2 = s_1;

  441.             s_1 = s;

  442.         }

  443. 

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

  445.             left->sample1 = s_1;

  446.             left->sample2 = s_2;

  447.             s_1 = right->sample1;

  448.             s_2 = right->sample2;

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

  450.         }

  451. 

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

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

  454. 

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

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

  457. 

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

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

  460. 

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

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

  463.             CLAMP_TO_SHORT(s);

  464.             *out = s;

  465.             out += inc;

  466.             s_2 = s_1;

  467.             s_1 = s;

  468.         }

  469. 

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

  471.             right->sample1 = s_1;

  472.             right->sample2 = s_2;

  473.             out -= 1;

  474.         } else {

  475.             left->sample1 = s_1;

  476.             left->sample2 = s_2;

  477.         }

  478.     }

  479. }

  480. 

  481. 

  482. /* DK3 ADPCM support macro */

  483. #define DK3_GET_NEXT_NIBBLE() \

  484.     if (decode_top_nibble_next) \

  485.     { \

  486.         nibble = (last_byte >> 4) & 0x0F; \

  487.         decode_top_nibble_next = 0; \

  488.     } \

  489.     else \

  490.     { \

  491.         last_byte = *src++; \

  492.         if (src >= buf + buf_size) break; \

  493.         nibble = last_byte & 0x0F; \

  494.         decode_top_nibble_next = 1; \

  495.     }

  496. 

  497. static int adpcm_decode_frame(AVCodecContext *avctx,

  498. 			    void *data, int *data_size,

  499. 			    uint8_t *buf, int buf_size)

  500. {

  501.     ADPCMContext *c = avctx->priv_data;

  502.     ADPCMChannelStatus *cs;

  503.     int n, m, channel, i;

  504.     int block_predictor[2];

  505.     short *samples;

  506.     uint8_t *src;

  507.     int st; /* stereo */

  508. 

  509.     /* DK3 ADPCM accounting variables */

  510.     unsigned char last_byte = 0;

  511.     unsigned char nibble;

  512.     int decode_top_nibble_next = 0;

  513.     int diff_channel;

  514. 

  515.     /* EA ADPCM state variables */

  516.     uint32_t samples_in_chunk;

  517.     int32_t previous_left_sample, previous_right_sample;

  518.     int32_t current_left_sample, current_right_sample;

  519.     int32_t next_left_sample, next_right_sample;

  520.     int32_t coeff1l, coeff2l, coeff1r, coeff2r;

  521.     uint8_t shift_left, shift_right;

  522.     int count1, count2;

  523. 

  524.     if (!buf_size)

  525.         return 0;

  526. 

  527.     samples = data;

  528.     src = buf;

  529. 

  530.     st = avctx->channels == 2;

  531. 

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

  533.     case CODEC_ID_ADPCM_IMA_QT:

  534.         n = (buf_size - 2);/* >> 2*avctx->channels;*/

  535.         channel = c->channel;

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

  537.         /* (pppppp) (piiiiiii) */

  538. 

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

  540.         cs->predictor = (*src++) << 8;

  541.         cs->predictor |= (*src & 0x80);

  542.         cs->predictor &= 0xFF80;

  543. 

  544.         /* sign extension */

  545.         if(cs->predictor & 0x8000)

  546.             cs->predictor -= 0x10000;

  547. 

  548.         CLAMP_TO_SHORT(cs->predictor);

  549. 

  550.         cs->step_index = (*src++) & 0x7F;

  551. 

  552.         if (cs->step_index > 88) av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);

  553.         if (cs->step_index > 88) cs->step_index = 88;

  554. 

  555.         cs->step = step_table[cs->step_index];

  556. 

  557.         if (st && channel)

  558.             samples++;

  559. 

  560.         for(m=32; n>0 && m>0; n--, m--) { /* in QuickTime, IMA is encoded by chuncks of 34 bytes (=64 samples) */

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

  562.             samples += avctx->channels;

  563.             *samples = adpcm_ima_expand_nibble(cs, (src[0] >> 4) & 0x0F, 3);

  564.             samples += avctx->channels;

  565.             src ++;

  566.         }

  567. 

  568.         if(st) { /* handle stereo interlacing */

  569.             c->channel = (channel + 1) % 2; /* we get one packet for left, then one for right data */

  570.             if(channel == 1) { /* wait for the other packet before outputing anything */

  571.                 *data_size = 0;

  572.                 return src - buf;

  573.             }

  574.         }

  575.         break;

  576.     case CODEC_ID_ADPCM_IMA_WAV:

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

  578.             buf_size = avctx->block_align;

  579. 

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

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

  582.             cs->predictor = *src++;

  583.             cs->predictor |= (*src++) << 8;

  584.             if(cs->predictor & 0x8000)

  585.                 cs->predictor -= 0x10000;

  586.             CLAMP_TO_SHORT(cs->predictor);

  587. 

  588. 	// XXX: is this correct ??: *samples++ = cs->predictor;

  589. 

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

  591.             if (cs->step_index < 0) cs->step_index = 0;

  592.             if (cs->step_index > 88) cs->step_index = 88;

  593.             if (*src++) av_log(avctx, AV_LOG_ERROR, "unused byte should be null !!\n"); /* unused */

  594.         }

  595. 

  596.         for(m=4; src < (buf + buf_size);) {

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

  598.             if (st)

  599.                 *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[4] & 0x0F, 3);

  600.             *samples++ = adpcm_ima_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F, 3);

  601. 	    if (st) {

  602.                 *samples++ = adpcm_ima_expand_nibble(&c->status[1], (src[4] >> 4) & 0x0F, 3);

  603. 		if (!--m) {

  604. 		    m=4;

  605. 		    src+=4;

  606. 		}

  607. 	    }

  608. 	    src++;

  609. 	}

  610.         break;

  611.     case CODEC_ID_ADPCM_4XM:

  612.         cs = &(c->status[0]);

  613.         c->status[0].predictor= (int16_t)(src[0] + (src[1]<<8)); src+=2;

  614.         if(st){

  615.             c->status[1].predictor= (int16_t)(src[0] + (src[1]<<8)); src+=2;

  616.         }

  617.         c->status[0].step_index= (int16_t)(src[0] + (src[1]<<8)); src+=2;

  618.         if(st){

  619.             c->status[1].step_index= (int16_t)(src[0] + (src[1]<<8)); src+=2;

  620.         }

  621.         if (cs->step_index < 0) cs->step_index = 0;

  622.         if (cs->step_index > 88) cs->step_index = 88;

  623. 

  624.         m= (buf_size - (src - buf))>>st;

  625.         for(i=0; i<m; i++) {

  626. 	    *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[i] & 0x0F, 4);

  627.             if (st)

  628.                 *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[i+m] & 0x0F, 4);

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

  630. 	    if (st)

  631.                 *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[i+m] >> 4, 4);

  632. 	}

  633. 

  634.         src += m<<st;

  635. 

  636.         break;

  637.     case CODEC_ID_ADPCM_MS:

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

  639.             buf_size = avctx->block_align;

  640.         n = buf_size - 7 * avctx->channels;

  641.         if (n < 0)

  642.             return -1;

  643.         block_predictor[0] = clip(*src++, 0, 7);

  644.         block_predictor[1] = 0;

  645.         if (st)

  646.             block_predictor[1] = clip(*src++, 0, 7);

  647.         c->status[0].idelta = (int16_t)((*src & 0xFF) | ((src[1] << 8) & 0xFF00));

  648.         src+=2;

  649.         if (st){

  650.             c->status[1].idelta = (int16_t)((*src & 0xFF) | ((src[1] << 8) & 0xFF00));

  651.             src+=2;

  652.         }

  653.         c->status[0].coeff1 = AdaptCoeff1[block_predictor[0]];

  654.         c->status[0].coeff2 = AdaptCoeff2[block_predictor[0]];

  655.         c->status[1].coeff1 = AdaptCoeff1[block_predictor[1]];

  656.         c->status[1].coeff2 = AdaptCoeff2[block_predictor[1]];

  657.         

  658.         c->status[0].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));

  659.         src+=2;

  660.         if (st) c->status[1].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));

  661.         if (st) src+=2;

  662.         c->status[0].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));

  663.         src+=2;

  664.         if (st) c->status[1].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));

  665.         if (st) src+=2;

  666. 

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

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

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

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

  671.         for(;n>0;n--) {

  672.             *samples++ = adpcm_ms_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F);

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

  674.             src ++;

  675.         }

  676.         break;

  677.     case CODEC_ID_ADPCM_IMA_DK4:

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

  679.             buf_size = avctx->block_align;

  680. 

  681.         c->status[0].predictor = (int16_t)(src[0] | (src[1] << 8));

  682.         c->status[0].step_index = src[2];

  683.         src += 4;

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

  685.         if (st) {

  686.             c->status[1].predictor = (int16_t)(src[0] | (src[1] << 8));

  687.             c->status[1].step_index = src[2];

  688.             src += 4;

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

  690.         }

  691.         while (src < buf + buf_size) {

  692. 

  693.             /* take care of the top nibble (always left or mono channel) */

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

  695.                 (src[0] >> 4) & 0x0F, 3);

  696. 

  697.             /* take care of the bottom nibble, which is right sample for

  698.              * stereo, or another mono sample */

  699.             if (st)

  700.                 *samples++ = adpcm_ima_expand_nibble(&c->status[1], 

  701.                     src[0] & 0x0F, 3);

  702.             else

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

  704.                     src[0] & 0x0F, 3);

  705. 

  706.             src++;

  707.         }

  708.         break;

  709.     case CODEC_ID_ADPCM_IMA_DK3:

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

  711.             buf_size = avctx->block_align;

  712. 

  713.         c->status[0].predictor = (int16_t)(src[10] | (src[11] << 8));

  714.         c->status[1].predictor = (int16_t)(src[12] | (src[13] << 8));

  715.         c->status[0].step_index = src[14];

  716.         c->status[1].step_index = src[15];

  717.         /* sign extend the predictors */

  718.         src += 16;

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

  720. 

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

  722.          * the buffer is consumed */

  723.         while (1) {

  724. 

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

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

  727. 

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

  729.             DK3_GET_NEXT_NIBBLE();

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

  731. 

  732.             /* process the diff channel predictor */

  733.             DK3_GET_NEXT_NIBBLE();

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

  735. 

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

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

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

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

  740. 

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

  742.             DK3_GET_NEXT_NIBBLE();

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

  744. 

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

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

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

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

  749.         }

  750.         break;

  751.     case CODEC_ID_ADPCM_IMA_WS:

  752.         /* no per-block initialization; just start decoding the data */

  753.         while (src < buf + buf_size) {

  754. 

  755.             if (st) {

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

  757.                     (src[0] >> 4) & 0x0F, 3);

  758.                 *samples++ = adpcm_ima_expand_nibble(&c->status[1], 

  759.                     src[0] & 0x0F, 3);

  760.             } else {

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

  762.                     (src[0] >> 4) & 0x0F, 3);

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

  764.                     src[0] & 0x0F, 3);

  765.             }

  766. 

  767.             src++;

  768.         }

  769.         break;

  770.     case CODEC_ID_ADPCM_XA:

  771.         c->status[0].sample1 = c->status[0].sample2 = 

  772.         c->status[1].sample1 = c->status[1].sample2 = 0;

  773.         while (buf_size >= 128) {

  774.             xa_decode(samples, src, &c->status[0], &c->status[1], 

  775.                 avctx->channels);

  776.             src += 128;

  777.             samples += 28 * 8;

  778.             buf_size -= 128;

  779.         }

  780.         break;

  781.     case CODEC_ID_ADPCM_EA:

  782.         samples_in_chunk = LE_32(src);

  783.         if (samples_in_chunk >= ((buf_size - 12) * 2)) {

  784.             src += buf_size;

  785.             break;

  786.         }

  787.         src += 4;

  788.         current_left_sample = (int16_t)LE_16(src);

  789.         src += 2;

  790.         previous_left_sample = (int16_t)LE_16(src);

  791.         src += 2;

  792.         current_right_sample = (int16_t)LE_16(src);

  793.         src += 2;

  794.         previous_right_sample = (int16_t)LE_16(src);

  795.         src += 2;

  796. 

  797.         for (count1 = 0; count1 < samples_in_chunk/28;count1++) {

  798.             coeff1l = ea_adpcm_table[(*src >> 4) & 0x0F];

  799.             coeff2l = ea_adpcm_table[((*src >> 4) & 0x0F) + 4];

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

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

  802.             src++;

  803. 

  804.             shift_left = ((*src >> 4) & 0x0F) + 8;

  805.             shift_right = (*src & 0x0F) + 8;

  806.             src++;

  807. 

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

  809.                 next_left_sample = (((*src & 0xF0) << 24) >> shift_left);

  810.                 next_right_sample = (((*src & 0x0F) << 28) >> shift_right);

  811.                 src++;

  812. 

  813.                 next_left_sample = (next_left_sample + 

  814.                     (current_left_sample * coeff1l) + 

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

  816.                 next_right_sample = (next_right_sample + 

  817.                     (current_right_sample * coeff1r) + 

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

  819.                 CLAMP_TO_SHORT(next_left_sample);

  820.                 CLAMP_TO_SHORT(next_right_sample);

  821. 

  822.                 previous_left_sample = current_left_sample;

  823.                 current_left_sample = next_left_sample;

  824.                 previous_right_sample = current_right_sample;

  825.                 current_right_sample = next_right_sample;

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

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

  828.             }

  829.         }

  830.         break;

  831.     case CODEC_ID_ADPCM_IMA_SMJPEG:

  832.         c->status[0].predictor = *src;

  833.         src += 2;

  834.         c->status[0].step_index = *src++;

  835.         src++;  /* skip another byte before getting to the meat */

  836.         while (src < buf + buf_size) {

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

  838.                 *src & 0x0F, 3);

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

  840.                 (*src >> 4) & 0x0F, 3);

  841.             src++;

  842.         }

  843.         break;

  844.     default:

  845.         *data_size = 0;

  846.         return -1;

  847.     }

  848.     *data_size = (uint8_t *)samples - (uint8_t *)data;

  849.     return src - buf;

  850. }

  851. 

  852. 

  853. 

  854. #ifdef CONFIG_ENCODERS

  855. #define ADPCM_ENCODER(id,name)                  \

  856. AVCodec name ## _encoder = {                    \

  857.     #name,                                      \

  858.     CODEC_TYPE_AUDIO,                           \

  859.     id,                                         \

  860.     sizeof(ADPCMContext),                       \

  861.     adpcm_encode_init,                          \

  862.     adpcm_encode_frame,                         \

  863.     adpcm_encode_close,                         \

  864.     NULL,                                       \

  865. };

  866. #else

  867. #define ADPCM_ENCODER(id,name)

  868. #endif

  869. 

  870. #ifdef CONFIG_DECODERS

  871. #define ADPCM_DECODER(id,name)                  \

  872. AVCodec name ## _decoder = {                    \

  873.     #name,                                      \

  874.     CODEC_TYPE_AUDIO,                           \

  875.     id,                                         \

  876.     sizeof(ADPCMContext),                       \

  877.     adpcm_decode_init,                          \

  878.     NULL,                                       \

  879.     NULL,                                       \

  880.     adpcm_decode_frame,                         \

  881. };

  882. #else

  883. #define ADPCM_DECODER(id,name)

  884. #endif

  885. 

  886. #define ADPCM_CODEC(id, name)                   \

  887. ADPCM_ENCODER(id,name) ADPCM_DECODER(id,name)

  888. 

  889. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);

  890. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);

  891. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK3, adpcm_ima_dk3);

  892. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK4, adpcm_ima_dk4);

  893. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WS, adpcm_ima_ws);

  894. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_SMJPEG, adpcm_ima_smjpeg);

  895. ADPCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);

  896. ADPCM_CODEC(CODEC_ID_ADPCM_4XM, adpcm_4xm);

  897. ADPCM_CODEC(CODEC_ID_ADPCM_XA, adpcm_xa);

  898. ADPCM_CODEC(CODEC_ID_ADPCM_ADX, adpcm_adx);

  899. ADPCM_CODEC(CODEC_ID_ADPCM_EA, adpcm_ea);

  900. 

  901. #undef ADPCM_CODEC