FFmpeg: libavcodec/shorten.c Source File

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shorten.c

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1 /*

2 * Shorten decoder

4 *

5 * This file is part of FFmpeg.

6 *

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

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

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

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

11 *

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

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

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

15 * Lesser General Public License for more details.

16 *

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

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

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

20 */

22 /**

23 * @file

24 * Shorten decoder

25 * @author Jeff Muizelaar

26 *

27 */

29 #include <limits.h>

30 #include "avcodec.h"

31 #include "bytestream.h"

32 #include "get_bits.h"

33 #include "golomb.h"

34 #include "internal.h"

36 #define MAX_CHANNELS 8

37 #define MAX_BLOCKSIZE 65535

39 #define OUT_BUFFER_SIZE 16384

41 #define ULONGSIZE 2

43 #define WAVE_FORMAT_PCM 0x0001

45 #define DEFAULT_BLOCK_SIZE 256

47 #define TYPESIZE 4

48 #define CHANSIZE 0

49 #define LPCQSIZE 2

50 #define ENERGYSIZE 3

51 #define BITSHIFTSIZE 2

53 #define TYPE_S8 1

54 #define TYPE_U8 2

55 #define TYPE_S16HL 3

56 #define TYPE_U16HL 4

57 #define TYPE_S16LH 5

58 #define TYPE_U16LH 6

60 #define NWRAP 3

61 #define NSKIPSIZE 1

63 #define LPCQUANT 5

64 #define V2LPCQOFFSET (1 << LPCQUANT)

66 #define FNSIZE 2

67 #define FN_DIFF0 0

68 #define FN_DIFF1 1

69 #define FN_DIFF2 2

70 #define FN_DIFF3 3

71 #define FN_QUIT 4

72 #define FN_BLOCKSIZE 5

73 #define FN_BITSHIFT 6

74 #define FN_QLPC 7

75 #define FN_ZERO 8

76 #define FN_VERBATIM 9

78 /** indicates if the FN_* command is audio or non-audio */

79 static const uint8_t is_audio_command[10] = { 1, 1, 1, 1, 0, 0, 0, 1, 1, 0 };

81 #define VERBATIM_CKSIZE_SIZE 5

82 #define VERBATIM_BYTE_SIZE 8

83 #define CANONICAL_HEADER_SIZE 44

85 typedef struct ShortenContext {

86 AVCodecContext *avctx;

87 GetBitContext gb;

89 int min_framesize, max_framesize;

90 unsigned channels;

92 int32_t *decoded[MAX_CHANNELS];

93 int32_t *decoded_base[MAX_CHANNELS];

94 int32_t *offset[MAX_CHANNELS];

95 int *coeffs;

96 uint8_t *bitstream;

97 int bitstream_size;

98 int bitstream_index;

99 unsigned int allocated_bitstream_size;

100 int header_size;

101 uint8_t header[OUT_BUFFER_SIZE];

102 int version;

103 int cur_chan;

104 int bitshift;

105 int nmean;

106 int internal_ftype;

107 int nwrap;

108 int blocksize;

109 int bitindex;

110 int32_t lpcqoffset;

111 int got_header;

112 int got_quit_command;

113 } ShortenContext;

114

115 static av_cold int shorten_decode_init(AVCodecContext *avctx)

116 {

117 ShortenContext *s = avctx->priv_data;

118 s->avctx = avctx;

119

120 return 0;

121 }

122

123 static int allocate_buffers(ShortenContext *s)

124 {

125 int i, chan, err;

126

127 for (chan = 0; chan < s->channels; chan++) {

128 if (FFMAX(1, s->nmean) >= UINT_MAX / sizeof(int32_t)) {

129 av_log(s->avctx, AV_LOG_ERROR, "nmean too large\n");

130 return AVERROR_INVALIDDATA;

131 }

132 if (s->blocksize + s->nwrap >= UINT_MAX / sizeof(int32_t) ||

133 s->blocksize + s->nwrap <= (unsigned)s->nwrap) {

134 av_log(s->avctx, AV_LOG_ERROR,

135 "s->blocksize + s->nwrap too large\n");

136 return AVERROR_INVALIDDATA;

137 }

138

139 if ((err = av_reallocp(&s->offset[chan],

140 sizeof(int32_t) *

141 FFMAX(1, s->nmean))) < 0)

142 return err;

143

144 if ((err = av_reallocp(&s->decoded_base[chan], (s->blocksize + s->nwrap) *

145 sizeof(s->decoded_base[0][0]))) < 0)

146 return err;

147 for (i = 0; i < s->nwrap; i++)

148 s->decoded_base[chan][i] = 0;

149 s->decoded[chan] = s->decoded_base[chan] + s->nwrap;

150 }

151

152 if ((err = av_reallocp(&s->coeffs, s->nwrap * sizeof(*s->coeffs))) < 0)

153 return err;

154

155 return 0;

156 }

157

158 static inline unsigned int get_uint(ShortenContext *s, int k)

159 {

160 if (s->version != 0)

161 k = get_ur_golomb_shorten(&s->gb, ULONGSIZE);

162 return get_ur_golomb_shorten(&s->gb, k);

163 }

164

165 static void fix_bitshift(ShortenContext *s, int32_t *buffer)

166 {

167 int i;

168

169 if (s->bitshift != 0)

170 for (i = 0; i < s->blocksize; i++)

171 buffer[i] <<= s->bitshift;

172 }

173

174 static int init_offset(ShortenContext *s)

175 {

176 int32_t mean = 0;

177 int chan, i;

178 int nblock = FFMAX(1, s->nmean);

179 /* initialise offset */

180 switch (s->internal_ftype) {

181 case TYPE_U8:

182 s->avctx->sample_fmt = AV_SAMPLE_FMT_U8P;

183 mean = 0x80;

184 break;

185 case TYPE_S16HL:

186 case TYPE_S16LH:

187 s->avctx->sample_fmt = AV_SAMPLE_FMT_S16P;

188 break;

189 default:

190 av_log(s->avctx, AV_LOG_ERROR, "unknown audio type\n");

191 return AVERROR_PATCHWELCOME;

192 }

193

194 for (chan = 0; chan < s->channels; chan++)

195 for (i = 0; i < nblock; i++)

196 s->offset[chan][i] = mean;

197 return 0;

198 }

199

200 static int decode_wave_header(AVCodecContext *avctx, const uint8_t *header,

201 int header_size)

202 {

203 int len, bps;

204 short wave_format;

205 GetByteContext gb;

206

207 bytestream2_init(&gb, header, header_size);

208

209 if (bytestream2_get_le32(&gb) != MKTAG('R', 'I', 'F', 'F')) {

210 av_log(avctx, AV_LOG_ERROR, "missing RIFF tag\n");

211 return AVERROR_INVALIDDATA;

212 }

213

214 bytestream2_skip(&gb, 4); /* chunk size */

215

216 if (bytestream2_get_le32(&gb) != MKTAG('W', 'A', 'V', 'E')) {

217 av_log(avctx, AV_LOG_ERROR, "missing WAVE tag\n");

218 return AVERROR_INVALIDDATA;

219 }

220

221 while (bytestream2_get_le32(&gb) != MKTAG('f', 'm', 't', ' ')) {

222 len = bytestream2_get_le32(&gb);

223 bytestream2_skip(&gb, len);

224 if (len < 0 || bytestream2_get_bytes_left(&gb) < 16) {

225 av_log(avctx, AV_LOG_ERROR, "no fmt chunk found\n");

226 return AVERROR_INVALIDDATA;

227 }

228 }

229 len = bytestream2_get_le32(&gb);

230

231 if (len < 16) {

232 av_log(avctx, AV_LOG_ERROR, "fmt chunk was too short\n");

233 return AVERROR_INVALIDDATA;

234 }

235

236 wave_format = bytestream2_get_le16(&gb);

237

238 switch (wave_format) {

239 case WAVE_FORMAT_PCM:

240 break;

241 default:

242 av_log(avctx, AV_LOG_ERROR, "unsupported wave format\n");

243 return AVERROR(ENOSYS);

244 }

245

246 bytestream2_skip(&gb, 2); // skip channels (already got from shorten header)

247 avctx->sample_rate = bytestream2_get_le32(&gb);

248 bytestream2_skip(&gb, 4); // skip bit rate (represents original uncompressed bit rate)

249 bytestream2_skip(&gb, 2); // skip block align (not needed)

250 bps = bytestream2_get_le16(&gb);

251 avctx->bits_per_coded_sample = bps;

252

253 if (bps != 16 && bps != 8) {

254 av_log(avctx, AV_LOG_ERROR, "unsupported number of bits per sample: %d\n", bps);

255 return AVERROR(ENOSYS);

256 }

257

258 len -= 16;

259 if (len > 0)

260 av_log(avctx, AV_LOG_INFO, "%d header bytes unparsed\n", len);

261

262 return 0;

263 }

264

265 static const int fixed_coeffs[][3] = {

266 { 0, 0, 0 },

267 { 1, 0, 0 },

268 { 2, -1, 0 },

269 { 3, -3, 1 }

270 };

271

272 static int decode_subframe_lpc(ShortenContext *s, int command, int channel,

273 int residual_size, int32_t coffset)

274 {

275 int pred_order, sum, qshift, init_sum, i, j;

276 const int *coeffs;

277

278 if (command == FN_QLPC) {

279 /* read/validate prediction order */

280 pred_order = get_ur_golomb_shorten(&s->gb, LPCQSIZE);

281 if (pred_order > s->nwrap) {

282 av_log(s->avctx, AV_LOG_ERROR, "invalid pred_order %d\n",

283 pred_order);

284 return AVERROR(EINVAL);

285 }

286 /* read LPC coefficients */

287 for (i = 0; i < pred_order; i++)

288 s->coeffs[i] = get_sr_golomb_shorten(&s->gb, LPCQUANT);

289 coeffs = s->coeffs;

290

291 qshift = LPCQUANT;

292 } else {

293 /* fixed LPC coeffs */

294 pred_order = command;

295 if (pred_order >= FF_ARRAY_ELEMS(fixed_coeffs)) {

296 av_log(s->avctx, AV_LOG_ERROR, "invalid pred_order %d\n",

297 pred_order);

298 return AVERROR_INVALIDDATA;

299 }

300 coeffs = fixed_coeffs[pred_order];

301 qshift = 0;

302 }

303

304 /* subtract offset from previous samples to use in prediction */

305 if (command == FN_QLPC && coffset)

306 for (i = -pred_order; i < 0; i++)

307 s->decoded[channel][i] -= coffset;

308

309 /* decode residual and do LPC prediction */

310 init_sum = pred_order ? (command == FN_QLPC ? s->lpcqoffset : 0) : coffset;

311 for (i = 0; i < s->blocksize; i++) {

312 sum = init_sum;

313 for (j = 0; j < pred_order; j++)

314 sum += coeffs[j] * s->decoded[channel][i - j - 1];

315 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) +

316 (sum >> qshift);

317 }

318

319 /* add offset to current samples */

320 if (command == FN_QLPC && coffset)

321 for (i = 0; i < s->blocksize; i++)

322 s->decoded[channel][i] += coffset;

323

324 return 0;

325 }

326

327 static int read_header(ShortenContext *s)

328 {

329 int i, ret;

330 int maxnlpc = 0;

331 /* shorten signature */

332 if (get_bits_long(&s->gb, 32) != AV_RB32("ajkg")) {

333 av_log(s->avctx, AV_LOG_ERROR, "missing shorten magic 'ajkg'\n");

334 return AVERROR_INVALIDDATA;

335 }

336

337 s->lpcqoffset = 0;

338 s->blocksize = DEFAULT_BLOCK_SIZE;

339 s->nmean = -1;

340 s->version = get_bits(&s->gb, 8);

341 s->internal_ftype = get_uint(s, TYPESIZE);

342

343 s->channels = get_uint(s, CHANSIZE);

344 if (!s->channels) {

345 av_log(s->avctx, AV_LOG_ERROR, "No channels reported\n");

346 return AVERROR_INVALIDDATA;

347 }

348 if (s->channels > MAX_CHANNELS) {

349 av_log(s->avctx, AV_LOG_ERROR, "too many channels: %d\n", s->channels);

350 s->channels = 0;

351 return AVERROR_INVALIDDATA;

352 }

353 s->avctx->channels = s->channels;

354

355 /* get blocksize if version > 0 */

356 if (s->version > 0) {

357 int skip_bytes;

358 unsigned blocksize;

359

360 blocksize = get_uint(s, av_log2(DEFAULT_BLOCK_SIZE));

361 if (!blocksize || blocksize > MAX_BLOCKSIZE) {

362 av_log(s->avctx, AV_LOG_ERROR,

363 "invalid or unsupported block size: %d\n",

364 blocksize);

365 return AVERROR(EINVAL);

366 }

367 s->blocksize = blocksize;

368

369 maxnlpc = get_uint(s, LPCQSIZE);

370 s->nmean = get_uint(s, 0);

371

372 skip_bytes = get_uint(s, NSKIPSIZE);

373 for (i = 0; i < skip_bytes; i++)

374 skip_bits(&s->gb, 8);

375 }

376 s->nwrap = FFMAX(NWRAP, maxnlpc);

377

378 if ((ret = allocate_buffers(s)) < 0)

379 return ret;

380

381 if ((ret = init_offset(s)) < 0)

382 return ret;

383

384 if (s->version > 1)

385 s->lpcqoffset = V2LPCQOFFSET;

386

387 if (get_ur_golomb_shorten(&s->gb, FNSIZE) != FN_VERBATIM) {

388 av_log(s->avctx, AV_LOG_ERROR,

389 "missing verbatim section at beginning of stream\n");

390 return AVERROR_INVALIDDATA;

391 }

392

393 s->header_size = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);

394 if (s->header_size >= OUT_BUFFER_SIZE ||

395 s->header_size < CANONICAL_HEADER_SIZE) {

396 av_log(s->avctx, AV_LOG_ERROR, "header is wrong size: %d\n",

397 s->header_size);

398 return AVERROR_INVALIDDATA;

399 }

400

401 for (i = 0; i < s->header_size; i++)

402 s->header[i] = (char)get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);

403

404 if ((ret = decode_wave_header(s->avctx, s->header, s->header_size)) < 0)

405 return ret;

406

407 s->cur_chan = 0;

408 s->bitshift = 0;

409

410 s->got_header = 1;

411

412 return 0;

413 }

414

415 static int shorten_decode_frame(AVCodecContext *avctx, void *data,

416 int *got_frame_ptr, AVPacket *avpkt)

417 {

418 AVFrame *frame = data;

419 const uint8_t *buf = avpkt->data;

420 int buf_size = avpkt->size;

421 ShortenContext *s = avctx->priv_data;

422 int i, input_buf_size = 0;

423 int ret;

424

425 /* allocate internal bitstream buffer */

426 if (s->max_framesize == 0) {

427 void *tmp_ptr;

428 s->max_framesize = 8192; // should hopefully be enough for the first header

429 tmp_ptr = av_fast_realloc(s->bitstream, &s->allocated_bitstream_size,

430 s->max_framesize + FF_INPUT_BUFFER_PADDING_SIZE);

431 if (!tmp_ptr) {

432 av_log(avctx, AV_LOG_ERROR, "error allocating bitstream buffer\n");

433 return AVERROR(ENOMEM);

434 }

435 memset(tmp_ptr, 0, s->allocated_bitstream_size);

436 s->bitstream = tmp_ptr;

437 }

438

439 /* append current packet data to bitstream buffer */

440 if (1 && s->max_framesize) { //FIXME truncated

441 buf_size = FFMIN(buf_size, s->max_framesize - s->bitstream_size);

442 input_buf_size = buf_size;

443

444 if (s->bitstream_index + s->bitstream_size + buf_size + FF_INPUT_BUFFER_PADDING_SIZE >

445 s->allocated_bitstream_size) {

446 memmove(s->bitstream, &s->bitstream[s->bitstream_index],

447 s->bitstream_size);

448 s->bitstream_index = 0;

449 }

450 if (buf)

451 memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], buf,

452 buf_size);

453 buf = &s->bitstream[s->bitstream_index];

454 buf_size += s->bitstream_size;

455 s->bitstream_size = buf_size;

456

457 /* do not decode until buffer has at least max_framesize bytes or

458 * the end of the file has been reached */

459 if (buf_size < s->max_framesize && avpkt->data) {

460 *got_frame_ptr = 0;

461 return input_buf_size;

462 }

463 }

464 /* init and position bitstream reader */

465 init_get_bits(&s->gb, buf, buf_size * 8);

466 skip_bits(&s->gb, s->bitindex);

467

468 /* process header or next subblock */

469 if (!s->got_header) {

470 if ((ret = read_header(s)) < 0)

471 return ret;

472 *got_frame_ptr = 0;

473 goto finish_frame;

474 }

475

476 /* if quit command was read previously, don't decode anything */

477 if (s->got_quit_command) {

478 *got_frame_ptr = 0;

479 return avpkt->size;

480 }

481

482 s->cur_chan = 0;

483 while (s->cur_chan < s->channels) {

484 unsigned cmd;

485 int len;

486

487 if (get_bits_left(&s->gb) < 3 + FNSIZE) {

488 *got_frame_ptr = 0;

489 break;

490 }

491

492 cmd = get_ur_golomb_shorten(&s->gb, FNSIZE);

493

494 if (cmd > FN_VERBATIM) {

495 av_log(avctx, AV_LOG_ERROR, "unknown shorten function %d\n", cmd);

496 *got_frame_ptr = 0;

497 break;

498 }

499

500 if (!is_audio_command[cmd]) {

501 /* process non-audio command */

502 switch (cmd) {

503 case FN_VERBATIM:

504 len = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);

505 while (len--)

506 get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);

507 break;

508 case FN_BITSHIFT: {

509 unsigned bitshift = get_ur_golomb_shorten(&s->gb, BITSHIFTSIZE);

510 if (bitshift > 31) {

511 av_log(avctx, AV_LOG_ERROR, "bitshift %d is invalid\n",

512 bitshift);

513 return AVERROR_PATCHWELCOME;

514 }

515 s->bitshift = bitshift;

516 break;

517 }

518 case FN_BLOCKSIZE: {

519 unsigned blocksize = get_uint(s, av_log2(s->blocksize));

520 if (blocksize > s->blocksize) {

521 av_log(avctx, AV_LOG_ERROR,

522 "Increasing block size is not supported\n");

523 return AVERROR_PATCHWELCOME;

524 }

525 if (!blocksize || blocksize > MAX_BLOCKSIZE) {

526 av_log(avctx, AV_LOG_ERROR, "invalid or unsupported "

527 "block size: %d\n", blocksize);

528 return AVERROR(EINVAL);

529 }

530 s->blocksize = blocksize;

531 break;

532 }

533 case FN_QUIT:

534 s->got_quit_command = 1;

535 break;

536 }

537 if (cmd == FN_BLOCKSIZE || cmd == FN_QUIT) {

538 *got_frame_ptr = 0;

539 break;

540 }

541 } else {

542 /* process audio command */

543 int residual_size = 0;

544 int channel = s->cur_chan;

545 int32_t coffset;

546

547 /* get Rice code for residual decoding */

548 if (cmd != FN_ZERO) {

549 residual_size = get_ur_golomb_shorten(&s->gb, ENERGYSIZE);

550 /* This is a hack as version 0 differed in the definition

551 * of get_sr_golomb_shorten(). */

552 if (s->version == 0)

553 residual_size--;

554 }

555

556 /* calculate sample offset using means from previous blocks */

557 if (s->nmean == 0)

558 coffset = s->offset[channel][0];

559 else {

560 int32_t sum = (s->version < 2) ? 0 : s->nmean / 2;

561 for (i = 0; i < s->nmean; i++)

562 sum += s->offset[channel][i];

563 coffset = sum / s->nmean;

564 if (s->version >= 2)

565 coffset = s->bitshift == 0 ? coffset : coffset >> s->bitshift - 1 >> 1;

566 }

567

568 /* decode samples for this channel */

569 if (cmd == FN_ZERO) {

570 for (i = 0; i < s->blocksize; i++)

571 s->decoded[channel][i] = 0;

572 } else {

573 if ((ret = decode_subframe_lpc(s, cmd, channel,

574 residual_size, coffset)) < 0)

575 return ret;

576 }

577

578 /* update means with info from the current block */

579 if (s->nmean > 0) {

580 int32_t sum = (s->version < 2) ? 0 : s->blocksize / 2;

581 for (i = 0; i < s->blocksize; i++)

582 sum += s->decoded[channel][i];

583

584 for (i = 1; i < s->nmean; i++)

585 s->offset[channel][i - 1] = s->offset[channel][i];

586

587 if (s->version < 2)

588 s->offset[channel][s->nmean - 1] = sum / s->blocksize;

589 else

590 s->offset[channel][s->nmean - 1] = (sum / s->blocksize) << s->bitshift;

591 }

592

593 /* copy wrap samples for use with next block */

594 for (i = -s->nwrap; i < 0; i++)

595 s->decoded[channel][i] = s->decoded[channel][i + s->blocksize];

596

597 /* shift samples to add in unused zero bits which were removed

598 * during encoding */

599 fix_bitshift(s, s->decoded[channel]);

600

601 /* if this is the last channel in the block, output the samples */

602 s->cur_chan++;

603 if (s->cur_chan == s->channels) {

604 uint8_t *samples_u8;

605 int16_t *samples_s16;

606 int chan;

607

608 /* get output buffer */

609 frame->nb_samples = s->blocksize;

610 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)

611 return ret;

612

613 for (chan = 0; chan < s->channels; chan++) {

614 samples_u8 = ((uint8_t **)frame->extended_data)[chan];

615 samples_s16 = ((int16_t **)frame->extended_data)[chan];

616 for (i = 0; i < s->blocksize; i++) {

617 switch (s->internal_ftype) {

618 case TYPE_U8:

619 *samples_u8++ = av_clip_uint8(s->decoded[chan][i]);

620 break;

621 case TYPE_S16HL:

622 case TYPE_S16LH:

623 *samples_s16++ = av_clip_int16(s->decoded[chan][i]);

624 break;

625 }

626 }

627 }

628

629 *got_frame_ptr = 1;

630 }

631 }

632 }

633 if (s->cur_chan < s->channels)

634 *got_frame_ptr = 0;

635

636 finish_frame:

637 s->bitindex = get_bits_count(&s->gb) - 8 * (get_bits_count(&s->gb) / 8);

638 i = get_bits_count(&s->gb) / 8;

639 if (i > buf_size) {

640 av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", i - buf_size);

641 s->bitstream_size = 0;

642 s->bitstream_index = 0;

643 return AVERROR_INVALIDDATA;

644 }

645 if (s->bitstream_size) {

646 s->bitstream_index += i;

647 s->bitstream_size -= i;

648 return input_buf_size;

649 } else

650 return i;

651 }

652

653 static av_cold int shorten_decode_close(AVCodecContext *avctx)

654 {

655 ShortenContext *s = avctx->priv_data;

656 int i;

657

658 for (i = 0; i < s->channels; i++) {

659 s->decoded[i] = NULL;

660 av_freep(&s->decoded_base[i]);

661 av_freep(&s->offset[i]);

662 }

663 av_freep(&s->bitstream);

664 av_freep(&s->coeffs);

665

666 return 0;

667 }

668

669 AVCodec ff_shorten_decoder = {

670 .name = "shorten",

671 .long_name = NULL_IF_CONFIG_SMALL("Shorten"),

672 .type = AVMEDIA_TYPE_AUDIO,

673 .id = AV_CODEC_ID_SHORTEN,

674 .priv_data_size = sizeof(ShortenContext),

675 .init = shorten_decode_init,

676 .close = shorten_decode_close,

677 .decode = shorten_decode_frame,

678 .capabilities = CODEC_CAP_DELAY | CODEC_CAP_DR1,

679 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,

680 AV_SAMPLE_FMT_U8P,

681 AV_SAMPLE_FMT_NONE },

682 };

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