3 * Copyright (c) 2001 Fabrice Bellard.
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.
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.
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
22 * First version by Francois Revol revol@free.fr
24 * Features and limitations:
26 * Reference documents:
27 * http://www.pcisys.net/~melanson/codecs/adpcm.txt
28 * http://www.geocities.com/SiliconValley/8682/aud3.txt
29 * http://openquicktime.sourceforge.net/plugins.htm
30 * XAnim sources (xa_codec.c) http://www.rasnaimaging.com/people/lapus/download.html
31 * http://www.cs.ucla.edu/~leec/mediabench/applications.html
32 * SoX source code http://home.sprynet.com/~cbagwell/sox.html
37 #define CLAMP_TO_SHORT(value) \
40 else if (value < -32768) \
43 /* step_table[] and index_table[] are from the ADPCM reference source */
44 /* This is the index table: */
45 static const int index_table[16] = {
46 -1, -1, -1, -1, 2, 4, 6, 8,
47 -1, -1, -1, -1, 2, 4, 6, 8,
50 /* This is the step table. Note that many programs use slight deviations from
51 * this table, but such deviations are negligible:
53 static const int step_table[89] = {
54 7, 8, 9, 10, 11, 12, 13, 14, 16, 17,
55 19, 21, 23, 25, 28, 31, 34, 37, 41, 45,
56 50, 55, 60, 66, 73, 80, 88, 97, 107, 118,
57 130, 143, 157, 173, 190, 209, 230, 253, 279, 307,
58 337, 371, 408, 449, 494, 544, 598, 658, 724, 796,
59 876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,
60 2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,
61 5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
62 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767
65 /* Those are for MS-ADPCM */
66 /* AdaptationTable[], AdaptCoeff1[], and AdaptCoeff2[] are from libsndfile */
67 static const int AdaptationTable[] = {
68 230, 230, 230, 230, 307, 409, 512, 614,
69 768, 614, 512, 409, 307, 230, 230, 230
72 static const int AdaptCoeff1[] = {
73 256, 512, 0, 192, 240, 460, 392
76 static const int AdaptCoeff2[] = {
77 0, -256, 0, 64, 0, -208, -232
82 typedef struct ADPCMChannelStatus {
97 typedef struct ADPCMContext {
98 int channel; /* for stereo MOVs, decode left, then decode right, then tell it's decoded */
99 ADPCMChannelStatus status[2];
100 short sample_buffer[32]; /* hold left samples while waiting for right samples */
103 /* XXX: implement encoding */
105 static int adpcm_encode_init(AVCodecContext *avctx)
107 if (avctx->channels > 2)
108 return -1; /* only stereo or mono =) */
109 switch(avctx->codec->id) {
110 case CODEC_ID_ADPCM_IMA_QT:
111 fprintf(stderr, "ADPCM: codec admcp_ima_qt unsupported for encoding !\n");
112 avctx->frame_size = 64; /* XXX: can multiple of avctx->channels * 64 (left and right blocks are interleaved) */
115 case CODEC_ID_ADPCM_IMA_WAV:
116 avctx->frame_size = (BLKSIZE - 4 * avctx->channels) * 8 / (4 * avctx->channels) + 1; /* each 16 bits sample gives one nibble */
117 /* and we have 4 bytes per channel overhead */
118 avctx->block_align = BLKSIZE;
119 /* seems frame_size isn't taken into account... have to buffer the samples :-( */
121 case CODEC_ID_ADPCM_MS:
122 fprintf(stderr, "ADPCM: codec admcp_ms unsupported for encoding !\n");
130 avctx->coded_frame= avcodec_alloc_frame();
131 avctx->coded_frame->key_frame= 1;
136 static int adpcm_encode_close(AVCodecContext *avctx)
138 av_freep(&avctx->coded_frame);
144 static inline unsigned char adpcm_ima_compress_sample(ADPCMChannelStatus *c, short sample)
147 unsigned char nibble;
149 int sign = 0; /* sign bit of the nibble (MSB) */
150 int delta, predicted_delta;
152 delta = sample - c->prev_sample;
159 step_index = c->step_index;
161 /* nibble = 4 * delta / step_table[step_index]; */
162 nibble = (delta << 2) / step_table[step_index];
167 step_index += index_table[nibble];
173 /* what the decoder will find */
174 predicted_delta = ((step_table[step_index] * nibble) / 4) + (step_table[step_index] / 8);
177 c->prev_sample -= predicted_delta;
179 c->prev_sample += predicted_delta;
181 CLAMP_TO_SHORT(c->prev_sample);
184 nibble += sign << 3; /* sign * 8 */
187 c->step_index = step_index;
192 static int adpcm_encode_frame(AVCodecContext *avctx,
193 unsigned char *frame, int buf_size, void *data)
198 ADPCMContext *c = avctx->priv_data;
201 samples = (short *)data;
202 /* n = (BLKSIZE - 4 * avctx->channels) / (2 * 8 * avctx->channels); */
204 switch(avctx->codec->id) {
205 case CODEC_ID_ADPCM_IMA_QT: /* XXX: can't test until we get .mov writer */
207 case CODEC_ID_ADPCM_IMA_WAV:
208 n = avctx->frame_size / 8;
209 c->status[0].prev_sample = (signed short)samples[0]; /* XXX */
210 /* c->status[0].step_index = 0; *//* XXX: not sure how to init the state machine */
211 *dst++ = (c->status[0].prev_sample) & 0xFF; /* little endian */
212 *dst++ = (c->status[0].prev_sample >> 8) & 0xFF;
213 *dst++ = (unsigned char)c->status[0].step_index;
214 *dst++ = 0; /* unknown */
216 if (avctx->channels == 2) {
217 c->status[1].prev_sample = (signed short)samples[0];
218 /* c->status[1].step_index = 0; */
219 *dst++ = (c->status[1].prev_sample) & 0xFF;
220 *dst++ = (c->status[1].prev_sample >> 8) & 0xFF;
221 *dst++ = (unsigned char)c->status[1].step_index;
226 /* stereo: 4 bytes (8 samples) for left, 4 bytes for right, 4 bytes left, ... */
228 *dst = adpcm_ima_compress_sample(&c->status[0], samples[0]) & 0x0F;
229 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels]) << 4) & 0xF0;
231 *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 2]) & 0x0F;
232 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 3]) << 4) & 0xF0;
234 *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 4]) & 0x0F;
235 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 5]) << 4) & 0xF0;
237 *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 6]) & 0x0F;
238 *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 7]) << 4) & 0xF0;
241 if (avctx->channels == 2) {
242 *dst = adpcm_ima_compress_sample(&c->status[1], samples[1]);
243 *dst |= adpcm_ima_compress_sample(&c->status[1], samples[3]) << 4;
245 *dst = adpcm_ima_compress_sample(&c->status[1], samples[5]);
246 *dst |= adpcm_ima_compress_sample(&c->status[1], samples[7]) << 4;
248 *dst = adpcm_ima_compress_sample(&c->status[1], samples[9]);
249 *dst |= adpcm_ima_compress_sample(&c->status[1], samples[11]) << 4;
251 *dst = adpcm_ima_compress_sample(&c->status[1], samples[13]);
252 *dst |= adpcm_ima_compress_sample(&c->status[1], samples[15]) << 4;
255 samples += 8 * avctx->channels;
264 static int adpcm_decode_init(AVCodecContext * avctx)
266 ADPCMContext *c = avctx->priv_data;
269 c->status[0].predictor = c->status[1].predictor = 0;
270 c->status[0].step_index = c->status[1].step_index = 0;
271 c->status[0].step = c->status[1].step = 0;
273 switch(avctx->codec->id) {
280 static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble)
284 int sign, delta, diff, step;
286 step = step_table[c->step_index];
287 step_index = c->step_index + index_table[(unsigned)nibble];
288 if (step_index < 0) step_index = 0;
289 else if (step_index > 88) step_index = 88;
295 if (delta & 4) diff += step;
296 if (delta & 2) diff += step >> 1;
297 if (delta & 1) diff += step >> 2;
299 diff = ((2 * delta + 1) * step) >> 3; // no jumps
301 predictor = c->predictor;
302 if (sign) predictor -= diff;
303 else predictor += diff;
305 CLAMP_TO_SHORT(predictor);
306 c->predictor = predictor;
307 c->step_index = step_index;
309 return (short)predictor;
312 static inline short adpcm_ms_expand_nibble(ADPCMChannelStatus *c, char nibble)
316 predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 256;
317 predictor += (signed)((nibble & 0x08)?(nibble - 0x10):(nibble)) * c->idelta;
318 CLAMP_TO_SHORT(predictor);
320 c->sample2 = c->sample1;
321 c->sample1 = predictor;
322 c->idelta = (AdaptationTable[(int)nibble] * c->idelta) / 256;
323 if (c->idelta < 16) c->idelta = 16;
325 return (short)predictor;
328 static int adpcm_decode_frame(AVCodecContext *avctx,
329 void *data, int *data_size,
330 uint8_t *buf, int buf_size)
332 ADPCMContext *c = avctx->priv_data;
333 ADPCMChannelStatus *cs;
335 int block_predictor[2];
343 st = avctx->channels == 2;
345 switch(avctx->codec->id) {
346 case CODEC_ID_ADPCM_IMA_QT:
347 n = (buf_size - 2);/* >> 2*avctx->channels;*/
348 channel = c->channel;
349 cs = &(c->status[channel]);
350 /* (pppppp) (piiiiiii) */
352 /* Bits 15-7 are the _top_ 9 bits of the 16-bit initial predictor value */
353 cs->predictor = (*src++) << 8;
354 cs->predictor |= (*src & 0x80);
355 cs->predictor &= 0xFF80;
358 if(cs->predictor & 0x8000)
359 cs->predictor -= 0x10000;
361 CLAMP_TO_SHORT(cs->predictor);
363 cs->step_index = (*src++) & 0x7F;
365 if (cs->step_index > 88) fprintf(stderr, "ERROR: step_index = %i\n", cs->step_index);
366 if (cs->step_index > 88) cs->step_index = 88;
368 cs->step = step_table[cs->step_index];
373 *samples++ = cs->predictor;
376 for(m=32; n>0 && m>0; n--, m--) { /* in QuickTime, IMA is encoded by chuncks of 34 bytes (=64 samples) */
377 *samples = adpcm_ima_expand_nibble(cs, src[0] & 0x0F);
378 samples += avctx->channels;
379 *samples = adpcm_ima_expand_nibble(cs, (src[0] >> 4) & 0x0F);
380 samples += avctx->channels;
384 if(st) { /* handle stereo interlacing */
385 c->channel = (channel + 1) % 2; /* we get one packet for left, then one for right data */
386 if(channel == 0) { /* wait for the other packet before outputing anything */
392 case CODEC_ID_ADPCM_IMA_WAV:
393 if (buf_size > BLKSIZE) {
394 if (avctx->block_align != 0)
395 buf_size = avctx->block_align;
399 // XXX: do as per-channel loop
400 cs = &(c->status[0]);
401 cs->predictor = (*src++) & 0x0FF;
402 cs->predictor |= ((*src++) << 8) & 0x0FF00;
403 if(cs->predictor & 0x8000)
404 cs->predictor -= 0x10000;
405 CLAMP_TO_SHORT(cs->predictor);
407 // XXX: is this correct ??: *samples++ = cs->predictor;
409 cs->step_index = *src++;
410 if (cs->step_index < 0) cs->step_index = 0;
411 if (cs->step_index > 88) cs->step_index = 88;
412 if (*src++) fprintf(stderr, "unused byte should be null !!\n"); /* unused */
415 cs = &(c->status[1]);
416 cs->predictor = (*src++) & 0x0FF;
417 cs->predictor |= ((*src++) << 8) & 0x0FF00;
418 if(cs->predictor & 0x8000)
419 cs->predictor -= 0x10000;
420 CLAMP_TO_SHORT(cs->predictor);
422 // XXX: is this correct ??: *samples++ = cs->predictor;
424 cs->step_index = *src++;
425 if (cs->step_index < 0) cs->step_index = 0;
426 if (cs->step_index > 88) cs->step_index = 88;
427 src++; /* if != 0 -> out-of-sync */
430 for(m=4; src < (buf + buf_size);) {
431 *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[0] & 0x0F);
433 *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[4] & 0x0F);
434 *samples++ = adpcm_ima_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F);
436 *samples++ = adpcm_ima_expand_nibble(&c->status[1], (src[4] >> 4) & 0x0F);
445 case CODEC_ID_ADPCM_MS:
447 if (buf_size > BLKSIZE) {
448 if (avctx->block_align != 0)
449 buf_size = avctx->block_align;
453 n = buf_size - 7 * avctx->channels;
456 block_predictor[0] = (*src++); /* should be bound */
457 block_predictor[0] = (block_predictor[0] < 0)?(0):((block_predictor[0] > 7)?(7):(block_predictor[0]));
458 block_predictor[1] = 0;
460 block_predictor[1] = (*src++);
461 block_predictor[1] = (block_predictor[1] < 0)?(0):((block_predictor[1] > 7)?(7):(block_predictor[1]));
462 c->status[0].idelta = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
463 if (c->status[0].idelta & 0x08000)
464 c->status[0].idelta -= 0x10000;
467 c->status[1].idelta = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
468 if (st && c->status[1].idelta & 0x08000)
469 c->status[1].idelta |= 0xFFFF0000;
472 c->status[0].coeff1 = AdaptCoeff1[block_predictor[0]];
473 c->status[0].coeff2 = AdaptCoeff2[block_predictor[0]];
474 c->status[1].coeff1 = AdaptCoeff1[block_predictor[1]];
475 c->status[1].coeff2 = AdaptCoeff2[block_predictor[1]];
477 c->status[0].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
479 if (st) c->status[1].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
481 c->status[0].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
483 if (st) c->status[1].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
486 *samples++ = c->status[0].sample1;
487 if (st) *samples++ = c->status[1].sample1;
488 *samples++ = c->status[0].sample2;
489 if (st) *samples++ = c->status[1].sample2;
491 *samples++ = adpcm_ms_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F);
492 *samples++ = adpcm_ms_expand_nibble(&c->status[st], src[0] & 0x0F);
500 *data_size = (uint8_t *)samples - (uint8_t *)data;
504 #define ADPCM_CODEC(id, name) \
505 AVCodec name ## _encoder = { \
509 sizeof(ADPCMContext), \
511 adpcm_encode_frame, \
512 adpcm_encode_close, \
515 AVCodec name ## _decoder = { \
519 sizeof(ADPCMContext), \
523 adpcm_decode_frame, \
526 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);
527 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);
528 ADPCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);