handle 0-length buffers
[libav.git] / libavcodec / adpcm.c
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 *
29 * Features and limitations:
30 *
31 * Reference documents:
32 * http://www.pcisys.net/~melanson/codecs/simpleaudio.html
33 * http://www.geocities.com/SiliconValley/8682/aud3.txt
34 * http://openquicktime.sourceforge.net/plugins.htm
35 * XAnim sources (xa_codec.c) http://www.rasnaimaging.com/people/lapus/download.html
36 * http://www.cs.ucla.edu/~leec/mediabench/applications.html
37 * SoX source code http://home.sprynet.com/~cbagwell/sox.html
38 *
39 * CD-ROM XA:
40 * http://ku-www.ss.titech.ac.jp/~yatsushi/xaadpcm.html
41 * vagpack & depack http://homepages.compuserve.de/bITmASTER32/psx-index.html
42 * readstr http://www.geocities.co.jp/Playtown/2004/
43 */
44
45 #define BLKSIZE 1024
46
47 #define CLAMP_TO_SHORT(value) \
48 if (value > 32767) \
49 value = 32767; \
50 else if (value < -32768) \
51 value = -32768; \
52
53 /* step_table[] and index_table[] are from the ADPCM reference source */
54 /* This is the index table: */
55 static const int index_table[16] = {
56 -1, -1, -1, -1, 2, 4, 6, 8,
57 -1, -1, -1, -1, 2, 4, 6, 8,
58 };
59
60 /**
61 * This is the step table. Note that many programs use slight deviations from
62 * this table, but such deviations are negligible:
63 */
64 static const int step_table[89] = {
65 7, 8, 9, 10, 11, 12, 13, 14, 16, 17,
66 19, 21, 23, 25, 28, 31, 34, 37, 41, 45,
67 50, 55, 60, 66, 73, 80, 88, 97, 107, 118,
68 130, 143, 157, 173, 190, 209, 230, 253, 279, 307,
69 337, 371, 408, 449, 494, 544, 598, 658, 724, 796,
70 876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,
71 2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,
72 5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
73 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767
74 };
75
76 /* These are for MS-ADPCM */
77 /* AdaptationTable[], AdaptCoeff1[], and AdaptCoeff2[] are from libsndfile */
78 static const int AdaptationTable[] = {
79 230, 230, 230, 230, 307, 409, 512, 614,
80 768, 614, 512, 409, 307, 230, 230, 230
81 };
82
83 static const int AdaptCoeff1[] = {
84 256, 512, 0, 192, 240, 460, 392
85 };
86
87 static const int AdaptCoeff2[] = {
88 0, -256, 0, 64, 0, -208, -232
89 };
90
91 /* These are for CD-ROM XA ADPCM */
92 static const int xa_adpcm_table[5][2] = {
93 { 0, 0 },
94 { 60, 0 },
95 { 115, -52 },
96 { 98, -55 },
97 { 122, -60 }
98 };
99
100 /* end of tables */
101
102 typedef struct ADPCMChannelStatus {
103 int predictor;
104 short int step_index;
105 int step;
106 /* for encoding */
107 int prev_sample;
108
109 /* MS version */
110 short sample1;
111 short sample2;
112 int coeff1;
113 int coeff2;
114 int idelta;
115 } ADPCMChannelStatus;
116
117 typedef struct ADPCMContext {
118 int channel; /* for stereo MOVs, decode left, then decode right, then tell it's decoded */
119 ADPCMChannelStatus status[2];
120 short sample_buffer[32]; /* hold left samples while waiting for right samples */
121 } ADPCMContext;
122
123 /* XXX: implement encoding */
124
125 #ifdef CONFIG_ENCODERS
126 static int adpcm_encode_init(AVCodecContext *avctx)
127 {
128 if (avctx->channels > 2)
129 return -1; /* only stereo or mono =) */
130 switch(avctx->codec->id) {
131 case CODEC_ID_ADPCM_IMA_QT:
132 av_log(avctx, AV_LOG_ERROR, "ADPCM: codec adpcm_ima_qt unsupported for encoding !\n");
133 avctx->frame_size = 64; /* XXX: can multiple of avctx->channels * 64 (left and right blocks are interleaved) */
134 return -1;
135 break;
136 case CODEC_ID_ADPCM_IMA_WAV:
137 avctx->frame_size = (BLKSIZE - 4 * avctx->channels) * 8 / (4 * avctx->channels) + 1; /* each 16 bits sample gives one nibble */
138 /* and we have 4 bytes per channel overhead */
139 avctx->block_align = BLKSIZE;
140 /* seems frame_size isn't taken into account... have to buffer the samples :-( */
141 break;
142 case CODEC_ID_ADPCM_MS:
143 av_log(avctx, AV_LOG_ERROR, "ADPCM: codec adpcm_ms unsupported for encoding !\n");
144 return -1;
145 break;
146 default:
147 return -1;
148 break;
149 }
150
151 avctx->coded_frame= avcodec_alloc_frame();
152 avctx->coded_frame->key_frame= 1;
153
154 return 0;
155 }
156
157 static int adpcm_encode_close(AVCodecContext *avctx)
158 {
159 av_freep(&avctx->coded_frame);
160
161 return 0;
162 }
163
164
165 static inline unsigned char adpcm_ima_compress_sample(ADPCMChannelStatus *c, short sample)
166 {
167 int step_index;
168 unsigned char nibble;
169
170 int sign = 0; /* sign bit of the nibble (MSB) */
171 int delta, predicted_delta;
172
173 delta = sample - c->prev_sample;
174
175 if (delta < 0) {
176 sign = 1;
177 delta = -delta;
178 }
179
180 step_index = c->step_index;
181
182 /* nibble = 4 * delta / step_table[step_index]; */
183 nibble = (delta << 2) / step_table[step_index];
184
185 if (nibble > 7)
186 nibble = 7;
187
188 step_index += index_table[nibble];
189 if (step_index < 0)
190 step_index = 0;
191 if (step_index > 88)
192 step_index = 88;
193
194 /* what the decoder will find */
195 predicted_delta = ((step_table[step_index] * nibble) / 4) + (step_table[step_index] / 8);
196
197 if (sign)
198 c->prev_sample -= predicted_delta;
199 else
200 c->prev_sample += predicted_delta;
201
202 CLAMP_TO_SHORT(c->prev_sample);
203
204
205 nibble += sign << 3; /* sign * 8 */
206
207 /* save back */
208 c->step_index = step_index;
209
210 return nibble;
211 }
212
213 static int adpcm_encode_frame(AVCodecContext *avctx,
214 unsigned char *frame, int buf_size, void *data)
215 {
216 int n;
217 short *samples;
218 unsigned char *dst;
219 ADPCMContext *c = avctx->priv_data;
220
221 dst = frame;
222 samples = (short *)data;
223 /* n = (BLKSIZE - 4 * avctx->channels) / (2 * 8 * avctx->channels); */
224
225 switch(avctx->codec->id) {
226 case CODEC_ID_ADPCM_IMA_QT: /* XXX: can't test until we get .mov writer */
227 break;
228 case CODEC_ID_ADPCM_IMA_WAV:
229 n = avctx->frame_size / 8;
230 c->status[0].prev_sample = (signed short)samples[0]; /* XXX */
231 /* c->status[0].step_index = 0; *//* XXX: not sure how to init the state machine */
232 *dst++ = (c->status[0].prev_sample) & 0xFF; /* little endian */
233 *dst++ = (c->status[0].prev_sample >> 8) & 0xFF;
234 *dst++ = (unsigned char)c->status[0].step_index;
235 *dst++ = 0; /* unknown */
236 samples++;
237 if (avctx->channels == 2) {
238 c->status[1].prev_sample = (signed short)samples[1];
239 /* c->status[1].step_index = 0; */
240 *dst++ = (c->status[1].prev_sample) & 0xFF;
241 *dst++ = (c->status[1].prev_sample >> 8) & 0xFF;
242 *dst++ = (unsigned char)c->status[1].step_index;
243 *dst++ = 0;
244 samples++;
245 }
246
247 /* stereo: 4 bytes (8 samples) for left, 4 bytes for right, 4 bytes left, ... */
248 for (; n>0; n--) {
249 *dst = adpcm_ima_compress_sample(&c->status[0], samples[0]) & 0x0F;
250 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels]) << 4) & 0xF0;
251 dst++;
252 *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 2]) & 0x0F;
253 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 3]) << 4) & 0xF0;
254 dst++;
255 *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 4]) & 0x0F;
256 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 5]) << 4) & 0xF0;
257 dst++;
258 *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 6]) & 0x0F;
259 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 7]) << 4) & 0xF0;
260 dst++;
261 /* right channel */
262 if (avctx->channels == 2) {
263 *dst = adpcm_ima_compress_sample(&c->status[1], samples[1]);
264 *dst |= adpcm_ima_compress_sample(&c->status[1], samples[3]) << 4;
265 dst++;
266 *dst = adpcm_ima_compress_sample(&c->status[1], samples[5]);
267 *dst |= adpcm_ima_compress_sample(&c->status[1], samples[7]) << 4;
268 dst++;
269 *dst = adpcm_ima_compress_sample(&c->status[1], samples[9]);
270 *dst |= adpcm_ima_compress_sample(&c->status[1], samples[11]) << 4;
271 dst++;
272 *dst = adpcm_ima_compress_sample(&c->status[1], samples[13]);
273 *dst |= adpcm_ima_compress_sample(&c->status[1], samples[15]) << 4;
274 dst++;
275 }
276 samples += 8 * avctx->channels;
277 }
278 break;
279 default:
280 return -1;
281 }
282 return dst - frame;
283 }
284 #endif //CONFIG_ENCODERS
285
286 static int adpcm_decode_init(AVCodecContext * avctx)
287 {
288 ADPCMContext *c = avctx->priv_data;
289
290 c->channel = 0;
291 c->status[0].predictor = c->status[1].predictor = 0;
292 c->status[0].step_index = c->status[1].step_index = 0;
293 c->status[0].step = c->status[1].step = 0;
294
295 switch(avctx->codec->id) {
296 default:
297 break;
298 }
299 return 0;
300 }
301
302 static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble, int shift)
303 {
304 int step_index;
305 int predictor;
306 int sign, delta, diff, step;
307
308 step = step_table[c->step_index];
309 step_index = c->step_index + index_table[(unsigned)nibble];
310 if (step_index < 0) step_index = 0;
311 else if (step_index > 88) step_index = 88;
312
313 sign = nibble & 8;
314 delta = nibble & 7;
315 /* perform direct multiplication instead of series of jumps proposed by
316 * the reference ADPCM implementation since modern CPUs can do the mults
317 * quickly enough */
318 diff = ((2 * delta + 1) * step) >> shift;
319 predictor = c->predictor;
320 if (sign) predictor -= diff;
321 else predictor += diff;
322
323 CLAMP_TO_SHORT(predictor);
324 c->predictor = predictor;
325 c->step_index = step_index;
326
327 return (short)predictor;
328 }
329
330 static inline short adpcm_ms_expand_nibble(ADPCMChannelStatus *c, char nibble)
331 {
332 int predictor;
333
334 predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 256;
335 predictor += (signed)((nibble & 0x08)?(nibble - 0x10):(nibble)) * c->idelta;
336 CLAMP_TO_SHORT(predictor);
337
338 c->sample2 = c->sample1;
339 c->sample1 = predictor;
340 c->idelta = (AdaptationTable[(int)nibble] * c->idelta) / 256;
341 if (c->idelta < 16) c->idelta = 16;
342
343 return (short)predictor;
344 }
345
346 static void xa_decode(short *out, const unsigned char *in,
347 ADPCMChannelStatus *left, ADPCMChannelStatus *right, int inc)
348 {
349 int i, j;
350 int shift,filter,f0,f1;
351 int s_1,s_2;
352 int d,s,t;
353
354 for(i=0;i<4;i++) {
355
356 shift = 12 - (in[4+i*2] & 15);
357 filter = in[4+i*2] >> 4;
358 f0 = xa_adpcm_table[filter][0];
359 f1 = xa_adpcm_table[filter][1];
360
361 s_1 = left->sample1;
362 s_2 = left->sample2;
363
364 for(j=0;j<28;j++) {
365 d = in[16+i+j*4];
366
367 t = (signed char)(d<<4)>>4;
368 s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);
369 CLAMP_TO_SHORT(s);
370 *out = s;
371 out += inc;
372 s_2 = s_1;
373 s_1 = s;
374 }
375
376 if (inc==2) { /* stereo */
377 left->sample1 = s_1;
378 left->sample2 = s_2;
379 s_1 = right->sample1;
380 s_2 = right->sample2;
381 out = out + 1 - 28*2;
382 }
383
384 shift = 12 - (in[5+i*2] & 15);
385 filter = in[5+i*2] >> 4;
386
387 f0 = xa_adpcm_table[filter][0];
388 f1 = xa_adpcm_table[filter][1];
389
390 for(j=0;j<28;j++) {
391 d = in[16+i+j*4];
392
393 t = (signed char)d >> 4;
394 s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);
395 CLAMP_TO_SHORT(s);
396 *out = s;
397 out += inc;
398 s_2 = s_1;
399 s_1 = s;
400 }
401
402 if (inc==2) { /* stereo */
403 right->sample1 = s_1;
404 right->sample2 = s_2;
405 out -= 1;
406 } else {
407 left->sample1 = s_1;
408 left->sample2 = s_2;
409 }
410 }
411 }
412
413
414 /* DK3 ADPCM support macro */
415 #define DK3_GET_NEXT_NIBBLE() \
416 if (decode_top_nibble_next) \
417 { \
418 nibble = (last_byte >> 4) & 0x0F; \
419 decode_top_nibble_next = 0; \
420 } \
421 else \
422 { \
423 last_byte = *src++; \
424 if (src >= buf + buf_size) break; \
425 nibble = last_byte & 0x0F; \
426 decode_top_nibble_next = 1; \
427 }
428
429 static int adpcm_decode_frame(AVCodecContext *avctx,
430 void *data, int *data_size,
431 uint8_t *buf, int buf_size)
432 {
433 ADPCMContext *c = avctx->priv_data;
434 ADPCMChannelStatus *cs;
435 int n, m, channel, i;
436 int block_predictor[2];
437 short *samples;
438 uint8_t *src;
439 int st; /* stereo */
440
441 /* DK3 ADPCM accounting variables */
442 unsigned char last_byte = 0;
443 unsigned char nibble;
444 int decode_top_nibble_next = 0;
445 int diff_channel;
446
447 if (!buf_size)
448 return 0;
449
450 samples = data;
451 src = buf;
452
453 st = avctx->channels == 2;
454
455 switch(avctx->codec->id) {
456 case CODEC_ID_ADPCM_IMA_QT:
457 n = (buf_size - 2);/* >> 2*avctx->channels;*/
458 channel = c->channel;
459 cs = &(c->status[channel]);
460 /* (pppppp) (piiiiiii) */
461
462 /* Bits 15-7 are the _top_ 9 bits of the 16-bit initial predictor value */
463 cs->predictor = (*src++) << 8;
464 cs->predictor |= (*src & 0x80);
465 cs->predictor &= 0xFF80;
466
467 /* sign extension */
468 if(cs->predictor & 0x8000)
469 cs->predictor -= 0x10000;
470
471 CLAMP_TO_SHORT(cs->predictor);
472
473 cs->step_index = (*src++) & 0x7F;
474
475 if (cs->step_index > 88) av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);
476 if (cs->step_index > 88) cs->step_index = 88;
477
478 cs->step = step_table[cs->step_index];
479
480 if (st && channel)
481 samples++;
482
483 for(m=32; n>0 && m>0; n--, m--) { /* in QuickTime, IMA is encoded by chuncks of 34 bytes (=64 samples) */
484 *samples = adpcm_ima_expand_nibble(cs, src[0] & 0x0F, 3);
485 samples += avctx->channels;
486 *samples = adpcm_ima_expand_nibble(cs, (src[0] >> 4) & 0x0F, 3);
487 samples += avctx->channels;
488 src ++;
489 }
490
491 if(st) { /* handle stereo interlacing */
492 c->channel = (channel + 1) % 2; /* we get one packet for left, then one for right data */
493 if(channel == 1) { /* wait for the other packet before outputing anything */
494 *data_size = 0;
495 return src - buf;
496 }
497 }
498 break;
499 case CODEC_ID_ADPCM_IMA_WAV:
500 if (avctx->block_align != 0 && buf_size > avctx->block_align)
501 buf_size = avctx->block_align;
502
503 for(i=0; i<avctx->channels; i++){
504 cs = &(c->status[i]);
505 cs->predictor = *src++;
506 cs->predictor |= (*src++) << 8;
507 if(cs->predictor & 0x8000)
508 cs->predictor -= 0x10000;
509 CLAMP_TO_SHORT(cs->predictor);
510
511 // XXX: is this correct ??: *samples++ = cs->predictor;
512
513 cs->step_index = *src++;
514 if (cs->step_index < 0) cs->step_index = 0;
515 if (cs->step_index > 88) cs->step_index = 88;
516 if (*src++) av_log(avctx, AV_LOG_ERROR, "unused byte should be null !!\n"); /* unused */
517 }
518
519 for(m=4; src < (buf + buf_size);) {
520 *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[0] & 0x0F, 3);
521 if (st)
522 *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[4] & 0x0F, 3);
523 *samples++ = adpcm_ima_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F, 3);
524 if (st) {
525 *samples++ = adpcm_ima_expand_nibble(&c->status[1], (src[4] >> 4) & 0x0F, 3);
526 if (!--m) {
527 m=4;
528 src+=4;
529 }
530 }
531 src++;
532 }
533 break;
534 case CODEC_ID_ADPCM_4XM:
535 cs = &(c->status[0]);
536 c->status[0].predictor= (int16_t)(src[0] + (src[1]<<8)); src+=2;
537 if(st){
538 c->status[1].predictor= (int16_t)(src[0] + (src[1]<<8)); src+=2;
539 }
540 c->status[0].step_index= (int16_t)(src[0] + (src[1]<<8)); src+=2;
541 if(st){
542 c->status[1].step_index= (int16_t)(src[0] + (src[1]<<8)); src+=2;
543 }
544 if (cs->step_index < 0) cs->step_index = 0;
545 if (cs->step_index > 88) cs->step_index = 88;
546
547 m= (buf_size - (src - buf))>>st;
548 for(i=0; i<m; i++) {
549 *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[i] & 0x0F, 4);
550 if (st)
551 *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[i+m] & 0x0F, 4);
552 *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[i] >> 4, 4);
553 if (st)
554 *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[i+m] >> 4, 4);
555 }
556
557 src += m<<st;
558
559 break;
560 case CODEC_ID_ADPCM_MS:
561 if (avctx->block_align != 0 && buf_size > avctx->block_align)
562 buf_size = avctx->block_align;
563 n = buf_size - 7 * avctx->channels;
564 if (n < 0)
565 return -1;
566 block_predictor[0] = (*src++); /* should be bound */
567 block_predictor[0] = (block_predictor[0] < 0)?(0):((block_predictor[0] > 7)?(7):(block_predictor[0]));
568 block_predictor[1] = 0;
569 if (st)
570 block_predictor[1] = (*src++);
571 block_predictor[1] = (block_predictor[1] < 0)?(0):((block_predictor[1] > 7)?(7):(block_predictor[1]));
572 c->status[0].idelta = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
573 if (c->status[0].idelta & 0x08000)
574 c->status[0].idelta -= 0x10000;
575 src+=2;
576 if (st)
577 c->status[1].idelta = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
578 if (st && c->status[1].idelta & 0x08000)
579 c->status[1].idelta |= 0xFFFF0000;
580 if (st)
581 src+=2;
582 c->status[0].coeff1 = AdaptCoeff1[block_predictor[0]];
583 c->status[0].coeff2 = AdaptCoeff2[block_predictor[0]];
584 c->status[1].coeff1 = AdaptCoeff1[block_predictor[1]];
585 c->status[1].coeff2 = AdaptCoeff2[block_predictor[1]];
586
587 c->status[0].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
588 src+=2;
589 if (st) c->status[1].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
590 if (st) src+=2;
591 c->status[0].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
592 src+=2;
593 if (st) c->status[1].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
594 if (st) src+=2;
595
596 *samples++ = c->status[0].sample1;
597 if (st) *samples++ = c->status[1].sample1;
598 *samples++ = c->status[0].sample2;
599 if (st) *samples++ = c->status[1].sample2;
600 for(;n>0;n--) {
601 *samples++ = adpcm_ms_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F);
602 *samples++ = adpcm_ms_expand_nibble(&c->status[st], src[0] & 0x0F);
603 src ++;
604 }
605 break;
606 case CODEC_ID_ADPCM_IMA_DK4:
607 if (avctx->block_align != 0 && buf_size > avctx->block_align)
608 buf_size = avctx->block_align;
609
610 c->status[0].predictor = (src[0] | (src[1] << 8));
611 c->status[0].step_index = src[2];
612 src += 4;
613 if(c->status[0].predictor & 0x8000)
614 c->status[0].predictor -= 0x10000;
615 *samples++ = c->status[0].predictor;
616 if (st) {
617 c->status[1].predictor = (src[0] | (src[1] << 8));
618 c->status[1].step_index = src[2];
619 src += 4;
620 if(c->status[1].predictor & 0x8000)
621 c->status[1].predictor -= 0x10000;
622 *samples++ = c->status[1].predictor;
623 }
624 while (src < buf + buf_size) {
625
626 /* take care of the top nibble (always left or mono channel) */
627 *samples++ = adpcm_ima_expand_nibble(&c->status[0],
628 (src[0] >> 4) & 0x0F, 3);
629
630 /* take care of the bottom nibble, which is right sample for
631 * stereo, or another mono sample */
632 if (st)
633 *samples++ = adpcm_ima_expand_nibble(&c->status[1],
634 src[0] & 0x0F, 3);
635 else
636 *samples++ = adpcm_ima_expand_nibble(&c->status[0],
637 src[0] & 0x0F, 3);
638
639 src++;
640 }
641 break;
642 case CODEC_ID_ADPCM_IMA_DK3:
643 if (avctx->block_align != 0 && buf_size > avctx->block_align)
644 buf_size = avctx->block_align;
645
646 c->status[0].predictor = (src[10] | (src[11] << 8));
647 c->status[1].predictor = (src[12] | (src[13] << 8));
648 c->status[0].step_index = src[14];
649 c->status[1].step_index = src[15];
650 /* sign extend the predictors */
651 if(c->status[0].predictor & 0x8000)
652 c->status[0].predictor -= 0x10000;
653 if(c->status[1].predictor & 0x8000)
654 c->status[1].predictor -= 0x10000;
655 src += 16;
656 diff_channel = c->status[1].predictor;
657
658 /* the DK3_GET_NEXT_NIBBLE macro issues the break statement when
659 * the buffer is consumed */
660 while (1) {
661
662 /* for this algorithm, c->status[0] is the sum channel and
663 * c->status[1] is the diff channel */
664
665 /* process the first predictor of the sum channel */
666 DK3_GET_NEXT_NIBBLE();
667 adpcm_ima_expand_nibble(&c->status[0], nibble, 3);
668
669 /* process the diff channel predictor */
670 DK3_GET_NEXT_NIBBLE();
671 adpcm_ima_expand_nibble(&c->status[1], nibble, 3);
672
673 /* process the first pair of stereo PCM samples */
674 diff_channel = (diff_channel + c->status[1].predictor) / 2;
675 *samples++ = c->status[0].predictor + c->status[1].predictor;
676 *samples++ = c->status[0].predictor - c->status[1].predictor;
677
678 /* process the second predictor of the sum channel */
679 DK3_GET_NEXT_NIBBLE();
680 adpcm_ima_expand_nibble(&c->status[0], nibble, 3);
681
682 /* process the second pair of stereo PCM samples */
683 diff_channel = (diff_channel + c->status[1].predictor) / 2;
684 *samples++ = c->status[0].predictor + c->status[1].predictor;
685 *samples++ = c->status[0].predictor - c->status[1].predictor;
686 }
687 break;
688 case CODEC_ID_ADPCM_IMA_WS:
689 /* no per-block initialization; just start decoding the data */
690 while (src < buf + buf_size) {
691
692 if (st) {
693 *samples++ = adpcm_ima_expand_nibble(&c->status[0],
694 (src[0] >> 4) & 0x0F, 3);
695 *samples++ = adpcm_ima_expand_nibble(&c->status[1],
696 src[0] & 0x0F, 3);
697 } else {
698 *samples++ = adpcm_ima_expand_nibble(&c->status[0],
699 (src[0] >> 4) & 0x0F, 3);
700 *samples++ = adpcm_ima_expand_nibble(&c->status[0],
701 src[0] & 0x0F, 3);
702 }
703
704 src++;
705 }
706 break;
707 case CODEC_ID_ADPCM_XA:
708 c->status[0].sample1 = c->status[0].sample2 =
709 c->status[1].sample1 = c->status[1].sample2 = 0;
710 while (buf_size >= 128) {
711 xa_decode(samples, src, &c->status[0], &c->status[1],
712 avctx->channels);
713 src += 128;
714 samples += 28 * 8;
715 buf_size -= 128;
716 }
717 break;
718 default:
719 *data_size = 0;
720 return -1;
721 }
722 *data_size = (uint8_t *)samples - (uint8_t *)data;
723 return src - buf;
724 }
725
726
727
728 #ifdef CONFIG_ENCODERS
729 #define ADPCM_ENCODER(id,name) \
730 AVCodec name ## _encoder = { \
731 #name, \
732 CODEC_TYPE_AUDIO, \
733 id, \
734 sizeof(ADPCMContext), \
735 adpcm_encode_init, \
736 adpcm_encode_frame, \
737 adpcm_encode_close, \
738 NULL, \
739 };
740 #else
741 #define ADPCM_ENCODER(id,name)
742 #endif
743
744 #ifdef CONFIG_DECODERS
745 #define ADPCM_DECODER(id,name) \
746 AVCodec name ## _decoder = { \
747 #name, \
748 CODEC_TYPE_AUDIO, \
749 id, \
750 sizeof(ADPCMContext), \
751 adpcm_decode_init, \
752 NULL, \
753 NULL, \
754 adpcm_decode_frame, \
755 };
756 #else
757 #define ADPCM_DECODER(id,name)
758 #endif
759
760 #define ADPCM_CODEC(id, name) \
761 ADPCM_ENCODER(id,name) ADPCM_DECODER(id,name)
762
763 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);
764 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);
765 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK3, adpcm_ima_dk3);
766 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK4, adpcm_ima_dk4);
767 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WS, adpcm_ima_ws);
768 ADPCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);
769 ADPCM_CODEC(CODEC_ID_ADPCM_4XM, adpcm_4xm);
770 ADPCM_CODEC(CODEC_ID_ADPCM_XA, adpcm_xa);
771 ADPCM_CODEC(CODEC_ID_ADPCM_ADX, adpcm_adx);
772
773 #undef ADPCM_CODEC