falkTX
/
FFmpeg
mirror of https://github.com/falkTX/FFmpeg.git
1
0
Fork 0
Code Issues 0 Releases 338 Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
3006 Commits
32 Branches
313MB
Tree: 04a59bfb8d
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from '04a59bfb8d'
${ noResults }
FFmpeg/libavcodec/adpcm.c

861 lines
29KB
Raw Blame History 

  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 BE_16(x)  ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])

  49. #define LE_16(x)  ((((uint8_t*)(x))[1] << 8) | ((uint8_t*)(x))[0])

  50. #define LE_32(x)  ((((uint8_t*)(x))[3] << 24) | \

  51.                    (((uint8_t*)(x))[2] << 16) | \

  52.                    (((uint8_t*)(x))[1] << 8) | \

  53.                     ((uint8_t*)(x))[0])

  54. 

  55. #define CLAMP_TO_SHORT(value) \

  56. if (value > 32767) \

  57.     value = 32767; \

  58. else if (value < -32768) \

  59.     value = -32768; \

  60. 

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

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

  63. static const int index_table[16] = {

  64.     -1, -1, -1, -1, 2, 4, 6, 8,

  65.     -1, -1, -1, -1, 2, 4, 6, 8,

  66. };

  67. 

  68. /** 

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

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

  71.  */

  72. static const int step_table[89] = {

  73.     7, 8, 9, 10, 11, 12, 13, 14, 16, 17,

  74.     19, 21, 23, 25, 28, 31, 34, 37, 41, 45,

  75.     50, 55, 60, 66, 73, 80, 88, 97, 107, 118,

  76.     130, 143, 157, 173, 190, 209, 230, 253, 279, 307,

  77.     337, 371, 408, 449, 494, 544, 598, 658, 724, 796,

  78.     876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,

  79.     2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,

  80.     5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,

  81.     15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767

  82. };

  83. 

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

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

  86. static const int AdaptationTable[] = {

  87.         230, 230, 230, 230, 307, 409, 512, 614,

  88.         768, 614, 512, 409, 307, 230, 230, 230

  89. };

  90. 

  91. static const int AdaptCoeff1[] = {

  92.         256, 512, 0, 192, 240, 460, 392

  93. };

  94. 

  95. static const int AdaptCoeff2[] = {

  96.         0, -256, 0, 64, 0, -208, -232

  97. };

  98. 

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

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

  101.    {   0,   0 },

  102.    {  60,   0 },

  103.    { 115, -52 },

  104.    {  98, -55 },

  105.    { 122, -60 }

  106. };

  107. 

  108. static int ea_adpcm_table[] = {

  109.     0, 240, 460, 392, 0, 0, -208, -220, 0, 1,

  110.     3, 4, 7, 8, 10, 11, 0, -1, -3, -4

  111. };

  112. 

  113. /* end of tables */

  114. 

  115. typedef struct ADPCMChannelStatus {

  116.     int predictor;

  117.     short int step_index;

  118.     int step;

  119.     /* for encoding */

  120.     int prev_sample;

  121. 

  122.     /* MS version */

  123.     short sample1;

  124.     short sample2;

  125.     int coeff1;

  126.     int coeff2;

  127.     int idelta;

  128. } ADPCMChannelStatus;

  129. 

  130. typedef struct ADPCMContext {

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

  132.     ADPCMChannelStatus status[2];

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

  134. } ADPCMContext;

  135. 

  136. /* XXX: implement encoding */

  137. 

  138. #ifdef CONFIG_ENCODERS

  139. static int adpcm_encode_init(AVCodecContext *avctx)

  140. {

  141.     if (avctx->channels > 2)

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

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

  144.     case CODEC_ID_ADPCM_IMA_QT:

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

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

  147.         return -1;

  148.         break;

  149.     case CODEC_ID_ADPCM_IMA_WAV:

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

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

  152.         avctx->block_align = BLKSIZE;

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

  154.         break;

  155.     case CODEC_ID_ADPCM_MS:

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

  157.         return -1;

  158.         break;

  159.     default:

  160.         return -1;

  161.         break;

  162.     }

  163. 

  164.     avctx->coded_frame= avcodec_alloc_frame();

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

  166. 

  167.     return 0;

  168. }

  169. 

  170. static int adpcm_encode_close(AVCodecContext *avctx)

  171. {

  172.     av_freep(&avctx->coded_frame);

  173. 

  174.     return 0;

  175. }

  176. 

  177. 

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

  179. {

  180.     int step_index;

  181.     unsigned char nibble;

  182.     

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

  184.     int delta, predicted_delta;

  185. 

  186.     delta = sample - c->prev_sample;

  187. 

  188.     if (delta < 0) {

  189.         sign = 1;

  190.         delta = -delta;

  191.     }

  192. 

  193.     step_index = c->step_index;

  194. 

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

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

  197. 

  198.     if (nibble > 7)

  199.         nibble = 7;

  200. 

  201.     step_index += index_table[nibble];

  202.     if (step_index < 0)

  203.         step_index = 0;

  204.     if (step_index > 88)

  205.         step_index = 88;

  206. 

  207.     /* what the decoder will find */

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

  209. 

  210.     if (sign)

  211.         c->prev_sample -= predicted_delta;

  212.     else

  213.         c->prev_sample += predicted_delta;

  214. 

  215.     CLAMP_TO_SHORT(c->prev_sample);

  216. 

  217. 

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

  219. 

  220.     /* save back */

  221.     c->step_index = step_index;

  222. 

  223.     return nibble;

  224. }

  225. 

  226. static int adpcm_encode_frame(AVCodecContext *avctx,

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

  228. {

  229.     int n;

  230.     short *samples;

  231.     unsigned char *dst;

  232.     ADPCMContext *c = avctx->priv_data;

  233. 

  234.     dst = frame;

  235.     samples = (short *)data;

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

  237. 

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

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

  240.         break;

  241.     case CODEC_ID_ADPCM_IMA_WAV:

  242.         n = avctx->frame_size / 8;

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

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

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

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

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

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

  249.             samples++;

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

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

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

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

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

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

  256.                 *dst++ = 0;

  257.                 samples++;

  258.             }

  259.         

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

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

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

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

  264.                 dst++;

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

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

  267.                 dst++;

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

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

  270.                 dst++;

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

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

  273.                 dst++;

  274.                 /* right channel */

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

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

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

  278.                     dst++;

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

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

  281.                     dst++;

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

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

  284.                     dst++;

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

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

  287.                     dst++;

  288.                 }

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

  290.             }

  291.         break;

  292.     default:

  293.         return -1;

  294.     }

  295.     return dst - frame;

  296. }

  297. #endif //CONFIG_ENCODERS

  298. 

  299. static int adpcm_decode_init(AVCodecContext * avctx)

  300. {

  301.     ADPCMContext *c = avctx->priv_data;

  302. 

  303.     c->channel = 0;

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

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

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

  307. 

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

  309.     default:

  310.         break;

  311.     }

  312.     return 0;

  313. }

  314. 

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

  316. {

  317.     int step_index;

  318.     int predictor;

  319.     int sign, delta, diff, step;

  320. 

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

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

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

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

  325. 

  326.     sign = nibble & 8;

  327.     delta = nibble & 7;

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

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

  330.      * quickly enough */

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

  332.     predictor = c->predictor;

  333.     if (sign) predictor -= diff;

  334.     else predictor += diff;

  335. 

  336.     CLAMP_TO_SHORT(predictor);

  337.     c->predictor = predictor;

  338.     c->step_index = step_index;

  339. 

  340.     return (short)predictor;

  341. }

  342. 

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

  344. {

  345.     int predictor;

  346. 

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

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

  349.     CLAMP_TO_SHORT(predictor);

  350. 

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

  352.     c->sample1 = predictor;

  353.     c->idelta = (AdaptationTable[(int)nibble] * c->idelta) / 256;

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

  355. 

  356.     return (short)predictor;

  357. }

  358. 

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

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

  361. {

  362.     int i, j;

  363.     int shift,filter,f0,f1;

  364.     int s_1,s_2;

  365.     int d,s,t;

  366. 

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

  368. 

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

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

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

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

  373. 

  374.         s_1 = left->sample1;

  375.         s_2 = left->sample2;

  376. 

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

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

  379. 

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

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

  382.             CLAMP_TO_SHORT(s);

  383.             *out = s;

  384.             out += inc;

  385.             s_2 = s_1;

  386.             s_1 = s;

  387.         }

  388. 

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

  390.             left->sample1 = s_1;

  391.             left->sample2 = s_2;

  392.             s_1 = right->sample1;

  393.             s_2 = right->sample2;

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

  395.         }

  396. 

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

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

  399. 

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

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

  402. 

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

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

  405. 

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

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

  408.             CLAMP_TO_SHORT(s);

  409.             *out = s;

  410.             out += inc;

  411.             s_2 = s_1;

  412.             s_1 = s;

  413.         }

  414. 

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

  416.             right->sample1 = s_1;

  417.             right->sample2 = s_2;

  418.             out -= 1;

  419.         } else {

  420.             left->sample1 = s_1;

  421.             left->sample2 = s_2;

  422.         }

  423.     }

  424. }

  425. 

  426. 

  427. /* DK3 ADPCM support macro */

  428. #define DK3_GET_NEXT_NIBBLE() \

  429.     if (decode_top_nibble_next) \

  430.     { \

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

  432.         decode_top_nibble_next = 0; \

  433.     } \

  434.     else \

  435.     { \

  436.         last_byte = *src++; \

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

  438.         nibble = last_byte & 0x0F; \

  439.         decode_top_nibble_next = 1; \

  440.     }

  441. 

  442. static int adpcm_decode_frame(AVCodecContext *avctx,

  443. 			    void *data, int *data_size,

  444. 			    uint8_t *buf, int buf_size)

  445. {

  446.     ADPCMContext *c = avctx->priv_data;

  447.     ADPCMChannelStatus *cs;

  448.     int n, m, channel, i;

  449.     int block_predictor[2];

  450.     short *samples;

  451.     uint8_t *src;

  452.     int st; /* stereo */

  453. 

  454.     /* DK3 ADPCM accounting variables */

  455.     unsigned char last_byte = 0;

  456.     unsigned char nibble;

  457.     int decode_top_nibble_next = 0;

  458.     int diff_channel;

  459. 

  460.     /* EA ADPCM state variables */

  461.     uint32_t samples_in_chunk;

  462.     int32_t previous_left_sample, previous_right_sample;

  463.     int32_t current_left_sample, current_right_sample;

  464.     int32_t next_left_sample, next_right_sample;

  465.     int32_t coeff1l, coeff2l, coeff1r, coeff2r;

  466.     uint8_t shift_left, shift_right;

  467.     int count1, count2;

  468. 

  469.     if (!buf_size)

  470.         return 0;

  471. 

  472.     samples = data;

  473.     src = buf;

  474. 

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

  476. 

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

  478.     case CODEC_ID_ADPCM_IMA_QT:

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

  480.         channel = c->channel;

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

  482.         /* (pppppp) (piiiiiii) */

  483. 

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

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

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

  487.         cs->predictor &= 0xFF80;

  488. 

  489.         /* sign extension */

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

  491.             cs->predictor -= 0x10000;

  492. 

  493.         CLAMP_TO_SHORT(cs->predictor);

  494. 

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

  496. 

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

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

  499. 

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

  501. 

  502.         if (st && channel)

  503.             samples++;

  504. 

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

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

  507.             samples += avctx->channels;

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

  509.             samples += avctx->channels;

  510.             src ++;

  511.         }

  512. 

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

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

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

  516.                 *data_size = 0;

  517.                 return src - buf;

  518.             }

  519.         }

  520.         break;

  521.     case CODEC_ID_ADPCM_IMA_WAV:

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

  523.             buf_size = avctx->block_align;

  524. 

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

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

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

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

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

  530.                 cs->predictor -= 0x10000;

  531.             CLAMP_TO_SHORT(cs->predictor);

  532. 

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

  534. 

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

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

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

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

  539.         }

  540. 

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

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

  543.             if (st)

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

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

  546. 	    if (st) {

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

  548. 		if (!--m) {

  549. 		    m=4;

  550. 		    src+=4;

  551. 		}

  552. 	    }

  553. 	    src++;

  554. 	}

  555.         break;

  556.     case CODEC_ID_ADPCM_4XM:

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

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

  559.         if(st){

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

  561.         }

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

  563.         if(st){

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

  565.         }

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

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

  568. 

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

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

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

  572.             if (st)

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

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

  575. 	    if (st)

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

  577. 	}

  578. 

  579.         src += m<<st;

  580. 

  581.         break;

  582.     case CODEC_ID_ADPCM_MS:

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

  584.             buf_size = avctx->block_align;

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

  586.         if (n < 0)

  587.             return -1;

  588.         block_predictor[0] = (*src++); /* should be bound */

  589.         block_predictor[0] = (block_predictor[0] < 0)?(0):((block_predictor[0] > 7)?(7):(block_predictor[0]));

  590.         block_predictor[1] = 0;

  591.         if (st)

  592.             block_predictor[1] = (*src++);

  593.         block_predictor[1] = (block_predictor[1] < 0)?(0):((block_predictor[1] > 7)?(7):(block_predictor[1]));

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

  595.         if (c->status[0].idelta & 0x08000)

  596.             c->status[0].idelta -= 0x10000;

  597.         src+=2;

  598.         if (st)

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

  600.         if (st && c->status[1].idelta & 0x08000)

  601.             c->status[1].idelta |= 0xFFFF0000;

  602.         if (st)

  603.             src+=2;

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

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

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

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

  608.         

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

  610.         src+=2;

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

  612.         if (st) src+=2;

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

  614.         src+=2;

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

  616.         if (st) src+=2;

  617. 

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

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

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

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

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

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

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

  625.             src ++;

  626.         }

  627.         break;

  628.     case CODEC_ID_ADPCM_IMA_DK4:

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

  630.             buf_size = avctx->block_align;

  631. 

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

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

  634.         src += 4;

  635.         if(c->status[0].predictor & 0x8000)

  636.             c->status[0].predictor -= 0x10000;

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

  638.         if (st) {

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

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

  641.             src += 4;

  642.             if(c->status[1].predictor & 0x8000)

  643.                 c->status[1].predictor -= 0x10000;

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

  645.         }

  646.         while (src < buf + buf_size) {

  647. 

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

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

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

  651. 

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

  653.              * stereo, or another mono sample */

  654.             if (st)

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

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

  657.             else

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

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

  660. 

  661.             src++;

  662.         }

  663.         break;

  664.     case CODEC_ID_ADPCM_IMA_DK3:

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

  666.             buf_size = avctx->block_align;

  667. 

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

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

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

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

  672.         /* sign extend the predictors */

  673.         if(c->status[0].predictor & 0x8000)

  674.             c->status[0].predictor -= 0x10000;

  675.         if(c->status[1].predictor & 0x8000)

  676.             c->status[1].predictor -= 0x10000;

  677.         src += 16;

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

  679. 

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

  681.          * the buffer is consumed */

  682.         while (1) {

  683. 

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

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

  686. 

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

  688.             DK3_GET_NEXT_NIBBLE();

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

  690. 

  691.             /* process the diff channel predictor */

  692.             DK3_GET_NEXT_NIBBLE();

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

  694. 

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

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

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

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

  699. 

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

  701.             DK3_GET_NEXT_NIBBLE();

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

  703. 

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

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

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

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

  708.         }

  709.         break;

  710.     case CODEC_ID_ADPCM_IMA_WS:

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

  712.         while (src < buf + buf_size) {

  713. 

  714.             if (st) {

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

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

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

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

  719.             } else {

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

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

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

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

  724.             }

  725. 

  726.             src++;

  727.         }

  728.         break;

  729.     case CODEC_ID_ADPCM_XA:

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

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

  732.         while (buf_size >= 128) {

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

  734.                 avctx->channels);

  735.             src += 128;

  736.             samples += 28 * 8;

  737.             buf_size -= 128;

  738.         }

  739.         break;

  740.     case CODEC_ID_ADPCM_EA:

  741.         samples_in_chunk = LE_32(src);

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

  743.             src += buf_size;

  744.             break;

  745.         }

  746.         src += 4;

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

  748.         src += 2;

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

  750.         src += 2;

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

  752.         src += 2;

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

  754.         src += 2;

  755. 

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

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

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

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

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

  761.             src++;

  762. 

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

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

  765.             src++;

  766. 

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

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

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

  770.                 src++;

  771. 

  772.                 next_left_sample = (next_left_sample + 

  773.                     (current_left_sample * coeff1l) + 

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

  775.                 next_right_sample = (next_right_sample + 

  776.                     (current_right_sample * coeff1r) + 

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

  778.                 CLAMP_TO_SHORT(next_left_sample);

  779.                 CLAMP_TO_SHORT(next_right_sample);

  780. 

  781.                 previous_left_sample = current_left_sample;

  782.                 current_left_sample = next_left_sample;

  783.                 previous_right_sample = current_right_sample;

  784.                 current_right_sample = next_right_sample;

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

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

  787.             }

  788.         }

  789.         break;

  790.     case CODEC_ID_ADPCM_IMA_SMJPEG:

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

  792.         src += 2;

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

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

  795.         while (src < buf + buf_size) {

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

  797.                 *src & 0x0F, 3);

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

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

  800.             src++;

  801.         }

  802.         break;

  803.     default:

  804.         *data_size = 0;

  805.         return -1;

  806.     }

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

  808.     return src - buf;

  809. }

  810. 

  811. 

  812. 

  813. #ifdef CONFIG_ENCODERS

  814. #define ADPCM_ENCODER(id,name)                  \

  815. AVCodec name ## _encoder = {                    \

  816.     #name,                                      \

  817.     CODEC_TYPE_AUDIO,                           \

  818.     id,                                         \

  819.     sizeof(ADPCMContext),                       \

  820.     adpcm_encode_init,                          \

  821.     adpcm_encode_frame,                         \

  822.     adpcm_encode_close,                         \

  823.     NULL,                                       \

  824. };

  825. #else

  826. #define ADPCM_ENCODER(id,name)

  827. #endif

  828. 

  829. #ifdef CONFIG_DECODERS

  830. #define ADPCM_DECODER(id,name)                  \

  831. AVCodec name ## _decoder = {                    \

  832.     #name,                                      \

  833.     CODEC_TYPE_AUDIO,                           \

  834.     id,                                         \

  835.     sizeof(ADPCMContext),                       \

  836.     adpcm_decode_init,                          \

  837.     NULL,                                       \

  838.     NULL,                                       \

  839.     adpcm_decode_frame,                         \

  840. };

  841. #else

  842. #define ADPCM_DECODER(id,name)

  843. #endif

  844. 

  845. #define ADPCM_CODEC(id, name)                   \

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

  847. 

  848. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);

  849. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);

  850. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK3, adpcm_ima_dk3);

  851. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK4, adpcm_ima_dk4);

  852. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WS, adpcm_ima_ws);

  853. ADPCM_CODEC(CODEC_ID_ADPCM_IMA_SMJPEG, adpcm_ima_smjpeg);

  854. ADPCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);

  855. ADPCM_CODEC(CODEC_ID_ADPCM_4XM, adpcm_4xm);

  856. ADPCM_CODEC(CODEC_ID_ADPCM_XA, adpcm_xa);

  857. ADPCM_CODEC(CODEC_ID_ADPCM_ADX, adpcm_adx);

  858. ADPCM_CODEC(CODEC_ID_ADPCM_EA, adpcm_ea);

  859. 

  860. #undef ADPCM_CODEC