FFmpeg: libavcodec/adpcmenc.c Source File

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libavcodec

adpcmenc.c

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1 /*

3 *

4 * first version by Francois Revol (revol@free.fr)

5 * fringe ADPCM codecs (e.g., DK3, DK4, Westwood)

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

7 *

8 * This file is part of FFmpeg.

9 *

10 * FFmpeg is free software; you can redistribute it and/or

11 * modify it under the terms of the GNU Lesser General Public

12 * License as published by the Free Software Foundation; either

13 * version 2.1 of the License, or (at your option) any later version.

14 *

15 * FFmpeg is distributed in the hope that it will be useful,

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

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

18 * Lesser General Public License for more details.

19 *

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

21 * License along with FFmpeg; if not, write to the Free Software

22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

23 */

25 #include "avcodec.h"

26 #include "put_bits.h"

27 #include "bytestream.h"

28 #include "adpcm.h"

29 #include "adpcm_data.h"

30 #include "internal.h"

32 /**

33 * @file

34 * ADPCM encoders

35 * See ADPCM decoder reference documents for codec information.

36 */

38 typedef struct TrellisPath {

39 int nibble;

40 int prev;

41 } TrellisPath;

43 typedef struct TrellisNode {

44 uint32_t ssd;

45 int path;

46 int sample1;

47 int sample2;

48 int step;

49 } TrellisNode;

51 typedef struct ADPCMEncodeContext {

52 ADPCMChannelStatus status[6];

53 TrellisPath *paths;

54 TrellisNode *node_buf;

55 TrellisNode **nodep_buf;

56 uint8_t *trellis_hash;

57 } ADPCMEncodeContext;

59 #define FREEZE_INTERVAL 128

61 static av_cold int adpcm_encode_close(AVCodecContext *avctx);

63 static av_cold int adpcm_encode_init(AVCodecContext *avctx)

64 {

65 ADPCMEncodeContext *s = avctx->priv_data;

66 uint8_t *extradata;

67 int i;

68 int ret = AVERROR(ENOMEM);

70 if (avctx->channels > 2) {

71 av_log(avctx, AV_LOG_ERROR, "only stereo or mono is supported\n");

72 return AVERROR(EINVAL);

73 }

75 if (avctx->trellis && (unsigned)avctx->trellis > 16U) {

76 av_log(avctx, AV_LOG_ERROR, "invalid trellis size\n");

77 return AVERROR(EINVAL);

78 }

80 if (avctx->trellis) {

81 int frontier = 1 << avctx->trellis;

82 int max_paths = frontier * FREEZE_INTERVAL;

83 FF_ALLOC_OR_GOTO(avctx, s->paths,

84 max_paths * sizeof(*s->paths), error);

85 FF_ALLOC_OR_GOTO(avctx, s->node_buf,

86 2 * frontier * sizeof(*s->node_buf), error);

87 FF_ALLOC_OR_GOTO(avctx, s->nodep_buf,

88 2 * frontier * sizeof(*s->nodep_buf), error);

89 FF_ALLOC_OR_GOTO(avctx, s->trellis_hash,

90 65536 * sizeof(*s->trellis_hash), error);

91 }

93 avctx->bits_per_coded_sample = av_get_bits_per_sample(avctx->codec->id);

95 switch (avctx->codec->id) {

96 case AV_CODEC_ID_ADPCM_IMA_WAV:

97 /* each 16 bits sample gives one nibble

98 and we have 4 bytes per channel overhead */

99 avctx->frame_size = (BLKSIZE - 4 * avctx->channels) * 8 /

100 (4 * avctx->channels) + 1;

101 /* seems frame_size isn't taken into account...

102 have to buffer the samples :-( */

103 avctx->block_align = BLKSIZE;

104 avctx->bits_per_coded_sample = 4;

105 break;

106 case AV_CODEC_ID_ADPCM_IMA_QT:

107 avctx->frame_size = 64;

108 avctx->block_align = 34 * avctx->channels;

109 break;

110 case AV_CODEC_ID_ADPCM_MS:

111 /* each 16 bits sample gives one nibble

112 and we have 7 bytes per channel overhead */

113 avctx->frame_size = (BLKSIZE - 7 * avctx->channels) * 2 / avctx->channels + 2;

114 avctx->bits_per_coded_sample = 4;

115 avctx->block_align = BLKSIZE;

116 if (!(avctx->extradata = av_malloc(32 + FF_INPUT_BUFFER_PADDING_SIZE)))

117 goto error;

118 avctx->extradata_size = 32;

119 extradata = avctx->extradata;

120 bytestream_put_le16(&extradata, avctx->frame_size);

121 bytestream_put_le16(&extradata, 7); /* wNumCoef */

122 for (i = 0; i < 7; i++) {

123 bytestream_put_le16(&extradata, ff_adpcm_AdaptCoeff1[i] * 4);

124 bytestream_put_le16(&extradata, ff_adpcm_AdaptCoeff2[i] * 4);

125 }

126 break;

127 case AV_CODEC_ID_ADPCM_YAMAHA:

128 avctx->frame_size = BLKSIZE * 2 / avctx->channels;

129 avctx->block_align = BLKSIZE;

130 break;

131 case AV_CODEC_ID_ADPCM_SWF:

132 if (avctx->sample_rate != 11025 &&

133 avctx->sample_rate != 22050 &&

134 avctx->sample_rate != 44100) {

135 av_log(avctx, AV_LOG_ERROR, "Sample rate must be 11025, "

136 "22050 or 44100\n");

137 ret = AVERROR(EINVAL);

138 goto error;

139 }

140 avctx->frame_size = 512 * (avctx->sample_rate / 11025);

141 break;

142 default:

143 ret = AVERROR(EINVAL);

144 goto error;

145 }

146

147 return 0;

148 error:

149 adpcm_encode_close(avctx);

150 return ret;

151 }

152

153 static av_cold int adpcm_encode_close(AVCodecContext *avctx)

154 {

155 ADPCMEncodeContext *s = avctx->priv_data;

156 av_freep(&s->paths);

157 av_freep(&s->node_buf);

158 av_freep(&s->nodep_buf);

159 av_freep(&s->trellis_hash);

160

161 return 0;

162 }

163

164

165 static inline uint8_t adpcm_ima_compress_sample(ADPCMChannelStatus *c,

166 int16_t sample)

167 {

168 int delta = sample - c->prev_sample;

169 int nibble = FFMIN(7, abs(delta) * 4 /

170 ff_adpcm_step_table[c->step_index]) + (delta < 0) * 8;

171 c->prev_sample += ((ff_adpcm_step_table[c->step_index] *

172 ff_adpcm_yamaha_difflookup[nibble]) / 8);

173 c->prev_sample = av_clip_int16(c->prev_sample);

174 c->step_index = av_clip(c->step_index + ff_adpcm_index_table[nibble], 0, 88);

175 return nibble;

176 }

177

178 static inline uint8_t adpcm_ima_qt_compress_sample(ADPCMChannelStatus *c,

179 int16_t sample)

180 {

181 int delta = sample - c->prev_sample;

182 int diff, step = ff_adpcm_step_table[c->step_index];

183 int nibble = 8*(delta < 0);

184

185 delta= abs(delta);

186 diff = delta + (step >> 3);

187

188 if (delta >= step) {

189 nibble |= 4;

190 delta -= step;

191 }

192 step >>= 1;

193 if (delta >= step) {

194 nibble |= 2;

195 delta -= step;

196 }

197 step >>= 1;

198 if (delta >= step) {

199 nibble |= 1;

200 delta -= step;

201 }

202 diff -= delta;

203

204 if (nibble & 8)

205 c->prev_sample -= diff;

206 else

207 c->prev_sample += diff;

208

209 c->prev_sample = av_clip_int16(c->prev_sample);

210 c->step_index = av_clip(c->step_index + ff_adpcm_index_table[nibble], 0, 88);

211

212 return nibble;

213 }

214

215 static inline uint8_t adpcm_ms_compress_sample(ADPCMChannelStatus *c,

216 int16_t sample)

217 {

218 int predictor, nibble, bias;

219

220 predictor = (((c->sample1) * (c->coeff1)) +

221 (( c->sample2) * (c->coeff2))) / 64;

222

223 nibble = sample - predictor;

224 if (nibble >= 0)

225 bias = c->idelta / 2;

226 else

227 bias = -c->idelta / 2;

228

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

230 nibble = av_clip(nibble, -8, 7) & 0x0F;

231

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

233

234 c->sample2 = c->sample1;

235 c->sample1 = av_clip_int16(predictor);

236

237 c->idelta = (ff_adpcm_AdaptationTable[nibble] * c->idelta) >> 8;

238 if (c->idelta < 16)

239 c->idelta = 16;

240

241 return nibble;

242 }

243

244 static inline uint8_t adpcm_yamaha_compress_sample(ADPCMChannelStatus *c,

245 int16_t sample)

246 {

247 int nibble, delta;

248

249 if (!c->step) {

250 c->predictor = 0;

251 c->step = 127;

252 }

253

254 delta = sample - c->predictor;

255

256 nibble = FFMIN(7, abs(delta) * 4 / c->step) + (delta < 0) * 8;

257

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

259 c->predictor = av_clip_int16(c->predictor);

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

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

262

263 return nibble;

264 }

265

266 static void adpcm_compress_trellis(AVCodecContext *avctx,

267 const int16_t *samples, uint8_t *dst,

268 ADPCMChannelStatus *c, int n, int stride)

269 {

270 //FIXME 6% faster if frontier is a compile-time constant

271 ADPCMEncodeContext *s = avctx->priv_data;

272 const int frontier = 1 << avctx->trellis;

273 const int version = avctx->codec->id;

274 TrellisPath *paths = s->paths, *p;

275 TrellisNode *node_buf = s->node_buf;

276 TrellisNode **nodep_buf = s->nodep_buf;

277 TrellisNode **nodes = nodep_buf; // nodes[] is always sorted by .ssd

278 TrellisNode **nodes_next = nodep_buf + frontier;

279 int pathn = 0, froze = -1, i, j, k, generation = 0;

280 uint8_t *hash = s->trellis_hash;

281 memset(hash, 0xff, 65536 * sizeof(*hash));

282

283 memset(nodep_buf, 0, 2 * frontier * sizeof(*nodep_buf));

284 nodes[0] = node_buf + frontier;

285 nodes[0]->ssd = 0;

286 nodes[0]->path = 0;

287 nodes[0]->step = c->step_index;

288 nodes[0]->sample1 = c->sample1;

289 nodes[0]->sample2 = c->sample2;

290 if (version == AV_CODEC_ID_ADPCM_IMA_WAV ||

291 version == AV_CODEC_ID_ADPCM_IMA_QT ||

292 version == AV_CODEC_ID_ADPCM_SWF)

293 nodes[0]->sample1 = c->prev_sample;

294 if (version == AV_CODEC_ID_ADPCM_MS)

295 nodes[0]->step = c->idelta;

296 if (version == AV_CODEC_ID_ADPCM_YAMAHA) {

297 if (c->step == 0) {

298 nodes[0]->step = 127;

299 nodes[0]->sample1 = 0;

300 } else {

301 nodes[0]->step = c->step;

302 nodes[0]->sample1 = c->predictor;

303 }

304 }

305

306 for (i = 0; i < n; i++) {

307 TrellisNode *t = node_buf + frontier*(i&1);

308 TrellisNode **u;

309 int sample = samples[i * stride];

310 int heap_pos = 0;

311 memset(nodes_next, 0, frontier * sizeof(TrellisNode*));

312 for (j = 0; j < frontier && nodes[j]; j++) {

313 // higher j have higher ssd already, so they're likely

314 // to yield a suboptimal next sample too

315 const int range = (j < frontier / 2) ? 1 : 0;

316 const int step = nodes[j]->step;

317 int nidx;

318 if (version == AV_CODEC_ID_ADPCM_MS) {

319 const int predictor = ((nodes[j]->sample1 * c->coeff1) +

320 (nodes[j]->sample2 * c->coeff2)) / 64;

321 const int div = (sample - predictor) / step;

322 const int nmin = av_clip(div-range, -8, 6);

323 const int nmax = av_clip(div+range, -7, 7);

324 for (nidx = nmin; nidx <= nmax; nidx++) {

325 const int nibble = nidx & 0xf;

326 int dec_sample = predictor + nidx * step;

327 #define STORE_NODE(NAME, STEP_INDEX)\

328 int d;\

329 uint32_t ssd;\

330 int pos;\

331 TrellisNode *u;\

332 uint8_t *h;\

333 dec_sample = av_clip_int16(dec_sample);\

334 d = sample - dec_sample;\

335 ssd = nodes[j]->ssd + d*(unsigned)d;\

336 /* Check for wraparound, skip such samples completely. \

337 * Note, changing ssd to a 64 bit variable would be \

338 * simpler, avoiding this check, but it's slower on \

339 * x86 32 bit at the moment. */\

340 if (ssd < nodes[j]->ssd)\

341 goto next_##NAME;\

342 /* Collapse any two states with the same previous sample value. \

343 * One could also distinguish states by step and by 2nd to last

344 * sample, but the effects of that are negligible.

345 * Since nodes in the previous generation are iterated

346 * through a heap, they're roughly ordered from better to

347 * worse, but not strictly ordered. Therefore, an earlier

348 * node with the same sample value is better in most cases

349 * (and thus the current is skipped), but not strictly

350 * in all cases. Only skipping samples where ssd >=

351 * ssd of the earlier node with the same sample gives

352 * slightly worse quality, though, for some reason. */ \

353 h = &hash[(uint16_t) dec_sample];\

354 if (*h == generation)\

355 goto next_##NAME;\

356 if (heap_pos < frontier) {\

357 pos = heap_pos++;\

358 } else {\

359 /* Try to replace one of the leaf nodes with the new \

360 * one, but try a different slot each time. */\

361 pos = (frontier >> 1) +\

362 (heap_pos & ((frontier >> 1) - 1));\

363 if (ssd > nodes_next[pos]->ssd)\

364 goto next_##NAME;\

365 heap_pos++;\

366 }\

367 *h = generation;\

368 u = nodes_next[pos];\

369 if (!u) {\

370 av_assert1(pathn < FREEZE_INTERVAL << avctx->trellis);\

371 u = t++;\

372 nodes_next[pos] = u;\

373 u->path = pathn++;\

374 }\

375 u->ssd = ssd;\

376 u->step = STEP_INDEX;\

377 u->sample2 = nodes[j]->sample1;\

378 u->sample1 = dec_sample;\

379 paths[u->path].nibble = nibble;\

380 paths[u->path].prev = nodes[j]->path;\

381 /* Sift the newly inserted node up in the heap to \

382 * restore the heap property. */\

383 while (pos > 0) {\

384 int parent = (pos - 1) >> 1;\

385 if (nodes_next[parent]->ssd <= ssd)\

386 break;\

387 FFSWAP(TrellisNode*, nodes_next[parent], nodes_next[pos]);\

388 pos = parent;\

389 }\

390 next_##NAME:;

391 STORE_NODE(ms, FFMAX(16,

392 (ff_adpcm_AdaptationTable[nibble] * step) >> 8));

393 }

394 } else if (version == AV_CODEC_ID_ADPCM_IMA_WAV ||

395 version == AV_CODEC_ID_ADPCM_IMA_QT ||

396 version == AV_CODEC_ID_ADPCM_SWF) {

397 #define LOOP_NODES(NAME, STEP_TABLE, STEP_INDEX)\

398 const int predictor = nodes[j]->sample1;\

399 const int div = (sample - predictor) * 4 / STEP_TABLE;\

400 int nmin = av_clip(div - range, -7, 6);\

401 int nmax = av_clip(div + range, -6, 7);\

402 if (nmin <= 0)\

403 nmin--; /* distinguish -0 from +0 */\

404 if (nmax < 0)\

405 nmax--;\

406 for (nidx = nmin; nidx <= nmax; nidx++) {\

407 const int nibble = nidx < 0 ? 7 - nidx : nidx;\

408 int dec_sample = predictor +\

409 (STEP_TABLE *\

410 ff_adpcm_yamaha_difflookup[nibble]) / 8;\

411 STORE_NODE(NAME, STEP_INDEX);\

412 }

413 LOOP_NODES(ima, ff_adpcm_step_table[step],

414 av_clip(step + ff_adpcm_index_table[nibble], 0, 88));

415 } else { //AV_CODEC_ID_ADPCM_YAMAHA

416 LOOP_NODES(yamaha, step,

417 av_clip((step * ff_adpcm_yamaha_indexscale[nibble]) >> 8,

418 127, 24567));

419 #undef LOOP_NODES

420 #undef STORE_NODE

421 }

422 }

423

424 u = nodes;

425 nodes = nodes_next;

426 nodes_next = u;

427

428 generation++;

429 if (generation == 255) {

430 memset(hash, 0xff, 65536 * sizeof(*hash));

431 generation = 0;

432 }

433

434 // prevent overflow

435 if (nodes[0]->ssd > (1 << 28)) {

436 for (j = 1; j < frontier && nodes[j]; j++)

437 nodes[j]->ssd -= nodes[0]->ssd;

438 nodes[0]->ssd = 0;

439 }

440

441 // merge old paths to save memory

442 if (i == froze + FREEZE_INTERVAL) {

443 p = &paths[nodes[0]->path];

444 for (k = i; k > froze; k--) {

445 dst[k] = p->nibble;

446 p = &paths[p->prev];

447 }

448 froze = i;

449 pathn = 0;

450 // other nodes might use paths that don't coincide with the frozen one.

451 // checking which nodes do so is too slow, so just kill them all.

452 // this also slightly improves quality, but I don't know why.

453 memset(nodes + 1, 0, (frontier - 1) * sizeof(TrellisNode*));

454 }

455 }

456

457 p = &paths[nodes[0]->path];

458 for (i = n - 1; i > froze; i--) {

459 dst[i] = p->nibble;

460 p = &paths[p->prev];

461 }

462

463 c->predictor = nodes[0]->sample1;

464 c->sample1 = nodes[0]->sample1;

465 c->sample2 = nodes[0]->sample2;

466 c->step_index = nodes[0]->step;

467 c->step = nodes[0]->step;

468 c->idelta = nodes[0]->step;

469 }

470

471 static int adpcm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,

472 const AVFrame *frame, int *got_packet_ptr)

473 {

474 int n, i, ch, st, pkt_size, ret;

475 const int16_t *samples;

476 int16_t **samples_p;

477 uint8_t *dst;

478 ADPCMEncodeContext *c = avctx->priv_data;

479 uint8_t *buf;

480

481 samples = (const int16_t *)frame->data[0];

482 samples_p = (int16_t **)frame->extended_data;

483 st = avctx->channels == 2;

484

485 if (avctx->codec_id == AV_CODEC_ID_ADPCM_SWF)

486 pkt_size = (2 + avctx->channels * (22 + 4 * (frame->nb_samples - 1)) + 7) / 8;

487 else

488 pkt_size = avctx->block_align;

489 if ((ret = ff_alloc_packet2(avctx, avpkt, pkt_size)) < 0)

490 return ret;

491 dst = avpkt->data;

492

493 switch(avctx->codec->id) {

494 case AV_CODEC_ID_ADPCM_IMA_WAV:

495 {

496 int blocks, j;

497

498 blocks = (frame->nb_samples - 1) / 8;

499

500 for (ch = 0; ch < avctx->channels; ch++) {

501 ADPCMChannelStatus *status = &c->status[ch];

502 status->prev_sample = samples_p[ch][0];

503 /* status->step_index = 0;

504 XXX: not sure how to init the state machine */

505 bytestream_put_le16(&dst, status->prev_sample);

506 *dst++ = status->step_index;

507 *dst++ = 0; /* unknown */

508 }

509

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

511 if (avctx->trellis > 0) {

512 FF_ALLOC_OR_GOTO(avctx, buf, avctx->channels * blocks * 8, error);

513 for (ch = 0; ch < avctx->channels; ch++) {

514 adpcm_compress_trellis(avctx, &samples_p[ch][1],

515 buf + ch * blocks * 8, &c->status[ch],

516 blocks * 8, 1);

517 }

518 for (i = 0; i < blocks; i++) {

519 for (ch = 0; ch < avctx->channels; ch++) {

520 uint8_t *buf1 = buf + ch * blocks * 8 + i * 8;

521 for (j = 0; j < 8; j += 2)

522 *dst++ = buf1[j] | (buf1[j + 1] << 4);

523 }

524 }

525 av_free(buf);

526 } else {

527 for (i = 0; i < blocks; i++) {

528 for (ch = 0; ch < avctx->channels; ch++) {

529 ADPCMChannelStatus *status = &c->status[ch];

530 const int16_t *smp = &samples_p[ch][1 + i * 8];

531 for (j = 0; j < 8; j += 2) {

532 uint8_t v = adpcm_ima_compress_sample(status, smp[j ]);

533 v |= adpcm_ima_compress_sample(status, smp[j + 1]) << 4;

534 *dst++ = v;

535 }

536 }

537 }

538 }

539 break;

540 }

541 case AV_CODEC_ID_ADPCM_IMA_QT:

542 {

543 PutBitContext pb;

544 init_put_bits(&pb, dst, pkt_size * 8);

545

546 for (ch = 0; ch < avctx->channels; ch++) {

547 ADPCMChannelStatus *status = &c->status[ch];

548 put_bits(&pb, 9, (status->prev_sample & 0xFFFF) >> 7);

549 put_bits(&pb, 7, status->step_index);

550 if (avctx->trellis > 0) {

551 uint8_t buf[64];

552 adpcm_compress_trellis(avctx, &samples_p[ch][0], buf, status,

553 64, 1);

554 for (i = 0; i < 64; i++)

555 put_bits(&pb, 4, buf[i ^ 1]);

556 status->prev_sample = status->predictor;

557 } else {

558 for (i = 0; i < 64; i += 2) {

559 int t1, t2;

560 t1 = adpcm_ima_qt_compress_sample(status, samples_p[ch][i ]);

561 t2 = adpcm_ima_qt_compress_sample(status, samples_p[ch][i + 1]);

562 put_bits(&pb, 4, t2);

563 put_bits(&pb, 4, t1);

564 }

565 }

566 }

567

568 flush_put_bits(&pb);

569 break;

570 }

571 case AV_CODEC_ID_ADPCM_SWF:

572 {

573 PutBitContext pb;

574 init_put_bits(&pb, dst, pkt_size * 8);

575

576 n = frame->nb_samples - 1;

577

578 // store AdpcmCodeSize

579 put_bits(&pb, 2, 2); // set 4-bit flash adpcm format

580

581 // init the encoder state

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

583 // clip step so it fits 6 bits

584 c->status[i].step_index = av_clip(c->status[i].step_index, 0, 63);

585 put_sbits(&pb, 16, samples[i]);

586 put_bits(&pb, 6, c->status[i].step_index);

587 c->status[i].prev_sample = samples[i];

588 }

589

590 if (avctx->trellis > 0) {

591 FF_ALLOC_OR_GOTO(avctx, buf, 2 * n, error);

592 adpcm_compress_trellis(avctx, samples + avctx->channels, buf,

593 &c->status[0], n, avctx->channels);

594 if (avctx->channels == 2)

595 adpcm_compress_trellis(avctx, samples + avctx->channels + 1,

596 buf + n, &c->status[1], n,

597 avctx->channels);

598 for (i = 0; i < n; i++) {

599 put_bits(&pb, 4, buf[i]);

600 if (avctx->channels == 2)

601 put_bits(&pb, 4, buf[n + i]);

602 }

603 av_free(buf);

604 } else {

605 for (i = 1; i < frame->nb_samples; i++) {

606 put_bits(&pb, 4, adpcm_ima_compress_sample(&c->status[0],

607 samples[avctx->channels * i]));

608 if (avctx->channels == 2)

609 put_bits(&pb, 4, adpcm_ima_compress_sample(&c->status[1],

610 samples[2 * i + 1]));

611 }

612 }

613 flush_put_bits(&pb);

614 break;

615 }

616 case AV_CODEC_ID_ADPCM_MS:

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

618 int predictor = 0;

619 *dst++ = predictor;

620 c->status[i].coeff1 = ff_adpcm_AdaptCoeff1[predictor];

621 c->status[i].coeff2 = ff_adpcm_AdaptCoeff2[predictor];

622 }

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

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

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

626 bytestream_put_le16(&dst, c->status[i].idelta);

627 }

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

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

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

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

632 bytestream_put_le16(&dst, c->status[i].sample1);

633 }

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

635 bytestream_put_le16(&dst, c->status[i].sample2);

636

637 if (avctx->trellis > 0) {

638 n = avctx->block_align - 7 * avctx->channels;

639 FF_ALLOC_OR_GOTO(avctx, buf, 2 * n, error);

640 if (avctx->channels == 1) {

641 adpcm_compress_trellis(avctx, samples, buf, &c->status[0], n,

642 avctx->channels);

643 for (i = 0; i < n; i += 2)

644 *dst++ = (buf[i] << 4) | buf[i + 1];

645 } else {

646 adpcm_compress_trellis(avctx, samples, buf,

647 &c->status[0], n, avctx->channels);

648 adpcm_compress_trellis(avctx, samples + 1, buf + n,

649 &c->status[1], n, avctx->channels);

650 for (i = 0; i < n; i++)

651 *dst++ = (buf[i] << 4) | buf[n + i];

652 }

653 av_free(buf);

654 } else {

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

656 int nibble;

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

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

659 *dst++ = nibble;

660 }

661 }

662 break;

663 case AV_CODEC_ID_ADPCM_YAMAHA:

664 n = frame->nb_samples / 2;

665 if (avctx->trellis > 0) {

666 FF_ALLOC_OR_GOTO(avctx, buf, 2 * n * 2, error);

667 n *= 2;

668 if (avctx->channels == 1) {

669 adpcm_compress_trellis(avctx, samples, buf, &c->status[0], n,

670 avctx->channels);

671 for (i = 0; i < n; i += 2)

672 *dst++ = buf[i] | (buf[i + 1] << 4);

673 } else {

674 adpcm_compress_trellis(avctx, samples, buf,

675 &c->status[0], n, avctx->channels);

676 adpcm_compress_trellis(avctx, samples + 1, buf + n,

677 &c->status[1], n, avctx->channels);

678 for (i = 0; i < n; i++)

679 *dst++ = buf[i] | (buf[n + i] << 4);

680 }

681 av_free(buf);

682 } else

683 for (n *= avctx->channels; n > 0; n--) {

684 int nibble;

685 nibble = adpcm_yamaha_compress_sample(&c->status[ 0], *samples++);

686 nibble |= adpcm_yamaha_compress_sample(&c->status[st], *samples++) << 4;

687 *dst++ = nibble;

688 }

689 break;

690 default:

691 return AVERROR(EINVAL);

692 }

693

694 avpkt->size = pkt_size;

695 *got_packet_ptr = 1;

696 return 0;

697 error:

698 return AVERROR(ENOMEM);

699 }

700

701 static const enum AVSampleFormat sample_fmts[] = {

702 AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE

703 };

704

705 static const enum AVSampleFormat sample_fmts_p[] = {

706 AV_SAMPLE_FMT_S16P, AV_SAMPLE_FMT_NONE

707 };

708

709 #define ADPCM_ENCODER(id_, name_, sample_fmts_, long_name_) \

710 AVCodec ff_ ## name_ ## _encoder = { \

711 .name = #name_, \

712 .long_name = NULL_IF_CONFIG_SMALL(long_name_), \

713 .type = AVMEDIA_TYPE_AUDIO, \

714 .id = id_, \

715 .priv_data_size = sizeof(ADPCMEncodeContext), \

716 .init = adpcm_encode_init, \

717 .encode2 = adpcm_encode_frame, \

718 .close = adpcm_encode_close, \

719 .sample_fmts = sample_fmts_, \

720 }

721

722 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt, sample_fmts_p, "ADPCM IMA QuickTime");

723 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav, sample_fmts_p, "ADPCM IMA WAV");

724 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_MS, adpcm_ms, sample_fmts, "ADPCM Microsoft");

725 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_SWF, adpcm_swf, sample_fmts, "ADPCM Shockwave Flash");

726 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_YAMAHA, adpcm_yamaha, sample_fmts, "ADPCM Yamaha");

Generated on Sun Jul 20 2014 23:05:43 for FFmpeg by doxygen 1.8.2