FFmpeg: libavresample/utils.c Source File

FFmpeg

[フレーム]

libavresample

utils.c

Go to the documentation of this file.

1 /*

3 *

4 * This file is part of Libav.

5 *

6 * Libav is free software; you can redistribute it and/or

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

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

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

10 *

11 * Libav is distributed in the hope that it will be useful,

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

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

14 * Lesser General Public License for more details.

15 *

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

17 * License along with Libav; if not, write to the Free Software

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

19 */

21 #include "libavutil/common.h"

22 #include "libavutil/dict.h"

23 // #include "libavutil/error.h"

24 #include "libavutil/log.h"

25 #include "libavutil/mem.h"

26 #include "libavutil/opt.h"

28 #include "avresample.h"

29 #include "internal.h"

30 #include "audio_data.h"

31 #include "audio_convert.h"

32 #include "audio_mix.h"

33 #include "resample.h"

35 int avresample_open(AVAudioResampleContext *avr)

36 {

37 int ret;

39 /* set channel mixing parameters */

40 avr->in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);

41 if (avr->in_channels <= 0 || avr->in_channels > AVRESAMPLE_MAX_CHANNELS) {

42 av_log(avr, AV_LOG_ERROR, "Invalid input channel layout: %"PRIu64"\n",

43 avr->in_channel_layout);

44 return AVERROR(EINVAL);

45 }

46 avr->out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);

47 if (avr->out_channels <= 0 || avr->out_channels > AVRESAMPLE_MAX_CHANNELS) {

48 av_log(avr, AV_LOG_ERROR, "Invalid output channel layout: %"PRIu64"\n",

49 avr->out_channel_layout);

50 return AVERROR(EINVAL);

51 }

52 avr->resample_channels = FFMIN(avr->in_channels, avr->out_channels);

53 avr->downmix_needed = avr->in_channels > avr->out_channels;

54 avr->upmix_needed = avr->out_channels > avr->in_channels ||

55 (!avr->downmix_needed && (avr->mix_matrix ||

56 avr->in_channel_layout != avr->out_channel_layout));

57 avr->mixing_needed = avr->downmix_needed || avr->upmix_needed;

59 /* set resampling parameters */

60 avr->resample_needed = avr->in_sample_rate != avr->out_sample_rate ||

61 avr->force_resampling;

63 /* select internal sample format if not specified by the user */

64 if (avr->internal_sample_fmt == AV_SAMPLE_FMT_NONE &&

65 (avr->mixing_needed || avr->resample_needed)) {

66 enum AVSampleFormat in_fmt = av_get_planar_sample_fmt(avr->in_sample_fmt);

67 enum AVSampleFormat out_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);

68 int max_bps = FFMAX(av_get_bytes_per_sample(in_fmt),

69 av_get_bytes_per_sample(out_fmt));

70 if (max_bps <= 2) {

71 avr->internal_sample_fmt = AV_SAMPLE_FMT_S16P;

72 } else if (avr->mixing_needed) {

73 avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;

74 } else {

75 if (max_bps <= 4) {

76 if (in_fmt == AV_SAMPLE_FMT_S32P ||

77 out_fmt == AV_SAMPLE_FMT_S32P) {

78 if (in_fmt == AV_SAMPLE_FMT_FLTP ||

79 out_fmt == AV_SAMPLE_FMT_FLTP) {

80 /* if one is s32 and the other is flt, use dbl */

81 avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;

82 } else {

83 /* if one is s32 and the other is s32, s16, or u8, use s32 */

84 avr->internal_sample_fmt = AV_SAMPLE_FMT_S32P;

85 }

86 } else {

87 /* if one is flt and the other is flt, s16 or u8, use flt */

88 avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;

89 }

90 } else {

91 /* if either is dbl, use dbl */

92 avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;

93 }

94 }

95 av_log(avr, AV_LOG_DEBUG, "Using %s as internal sample format\n",

96 av_get_sample_fmt_name(avr->internal_sample_fmt));

97 }

99 /* treat all mono as planar for easier comparison */

100 if (avr->in_channels == 1)

101 avr->in_sample_fmt = av_get_planar_sample_fmt(avr->in_sample_fmt);

102 if (avr->out_channels == 1)

103 avr->out_sample_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);

104

105 /* we may need to add an extra conversion in order to remap channels if

106 the output format is not planar */

107 if (avr->use_channel_map && !avr->mixing_needed && !avr->resample_needed &&

108 !av_sample_fmt_is_planar(avr->out_sample_fmt)) {

109 avr->internal_sample_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);

110 }

111

112 /* set sample format conversion parameters */

113 if (avr->resample_needed || avr->mixing_needed)

114 avr->in_convert_needed = avr->in_sample_fmt != avr->internal_sample_fmt;

115 else

116 avr->in_convert_needed = avr->use_channel_map &&

117 !av_sample_fmt_is_planar(avr->out_sample_fmt);

118

119 if (avr->resample_needed || avr->mixing_needed || avr->in_convert_needed)

120 avr->out_convert_needed = avr->internal_sample_fmt != avr->out_sample_fmt;

121 else

122 avr->out_convert_needed = avr->in_sample_fmt != avr->out_sample_fmt;

123

124 avr->in_copy_needed = !avr->in_convert_needed && (avr->mixing_needed ||

125 (avr->use_channel_map && avr->resample_needed));

126

127 if (avr->use_channel_map) {

128 if (avr->in_copy_needed) {

129 avr->remap_point = REMAP_IN_COPY;

130 av_dlog(avr, "remap channels during in_copy\n");

131 } else if (avr->in_convert_needed) {

132 avr->remap_point = REMAP_IN_CONVERT;

133 av_dlog(avr, "remap channels during in_convert\n");

134 } else if (avr->out_convert_needed) {

135 avr->remap_point = REMAP_OUT_CONVERT;

136 av_dlog(avr, "remap channels during out_convert\n");

137 } else {

138 avr->remap_point = REMAP_OUT_COPY;

139 av_dlog(avr, "remap channels during out_copy\n");

140 }

141

142 #ifdef DEBUG

143 {

144 int ch;

145 av_dlog(avr, "output map: ");

146 if (avr->ch_map_info.do_remap)

147 for (ch = 0; ch < avr->in_channels; ch++)

148 av_dlog(avr, " % 2d", avr->ch_map_info.channel_map[ch]);

149 else

150 av_dlog(avr, "n/a");

151 av_dlog(avr, "\n");

152 av_dlog(avr, "copy map: ");

153 if (avr->ch_map_info.do_copy)

154 for (ch = 0; ch < avr->in_channels; ch++)

155 av_dlog(avr, " % 2d", avr->ch_map_info.channel_copy[ch]);

156 else

157 av_dlog(avr, "n/a");

158 av_dlog(avr, "\n");

159 av_dlog(avr, "zero map: ");

160 if (avr->ch_map_info.do_zero)

161 for (ch = 0; ch < avr->in_channels; ch++)

162 av_dlog(avr, " % 2d", avr->ch_map_info.channel_zero[ch]);

163 else

164 av_dlog(avr, "n/a");

165 av_dlog(avr, "\n");

166 av_dlog(avr, "input map: ");

167 for (ch = 0; ch < avr->in_channels; ch++)

168 av_dlog(avr, " % 2d", avr->ch_map_info.input_map[ch]);

169 av_dlog(avr, "\n");

170 }

171 #endif

172 } else

173 avr->remap_point = REMAP_NONE;

174

175 /* allocate buffers */

176 if (avr->in_copy_needed || avr->in_convert_needed) {

177 avr->in_buffer = ff_audio_data_alloc(FFMAX(avr->in_channels, avr->out_channels),

178 0, avr->internal_sample_fmt,

179 "in_buffer");

180 if (!avr->in_buffer) {

181 ret = AVERROR(EINVAL);

182 goto error;

183 }

184 }

185 if (avr->resample_needed) {

186 avr->resample_out_buffer = ff_audio_data_alloc(avr->out_channels,

187 0, avr->internal_sample_fmt,

188 "resample_out_buffer");

189 if (!avr->resample_out_buffer) {

190 ret = AVERROR(EINVAL);

191 goto error;

192 }

193 }

194 if (avr->out_convert_needed) {

195 avr->out_buffer = ff_audio_data_alloc(avr->out_channels, 0,

196 avr->out_sample_fmt, "out_buffer");

197 if (!avr->out_buffer) {

198 ret = AVERROR(EINVAL);

199 goto error;

200 }

201 }

202 avr->out_fifo = av_audio_fifo_alloc(avr->out_sample_fmt, avr->out_channels,

203 1024);

204 if (!avr->out_fifo) {

205 ret = AVERROR(ENOMEM);

206 goto error;

207 }

208

209 /* setup contexts */

210 if (avr->in_convert_needed) {

211 avr->ac_in = ff_audio_convert_alloc(avr, avr->internal_sample_fmt,

212 avr->in_sample_fmt, avr->in_channels,

213 avr->in_sample_rate,

214 avr->remap_point == REMAP_IN_CONVERT);

215 if (!avr->ac_in) {

216 ret = AVERROR(ENOMEM);

217 goto error;

218 }

219 }

220 if (avr->out_convert_needed) {

221 enum AVSampleFormat src_fmt;

222 if (avr->in_convert_needed)

223 src_fmt = avr->internal_sample_fmt;

224 else

225 src_fmt = avr->in_sample_fmt;

226 avr->ac_out = ff_audio_convert_alloc(avr, avr->out_sample_fmt, src_fmt,

227 avr->out_channels,

228 avr->out_sample_rate,

229 avr->remap_point == REMAP_OUT_CONVERT);

230 if (!avr->ac_out) {

231 ret = AVERROR(ENOMEM);

232 goto error;

233 }

234 }

235 if (avr->resample_needed) {

236 avr->resample = ff_audio_resample_init(avr);

237 if (!avr->resample) {

238 ret = AVERROR(ENOMEM);

239 goto error;

240 }

241 }

242 if (avr->mixing_needed) {

243 avr->am = ff_audio_mix_alloc(avr);

244 if (!avr->am) {

245 ret = AVERROR(ENOMEM);

246 goto error;

247 }

248 }

249

250 return 0;

251

252 error:

253 avresample_close(avr);

254 return ret;

255 }

256

257 void avresample_close(AVAudioResampleContext *avr)

258 {

259 ff_audio_data_free(&avr->in_buffer);

260 ff_audio_data_free(&avr->resample_out_buffer);

261 ff_audio_data_free(&avr->out_buffer);

262 av_audio_fifo_free(avr->out_fifo);

263 avr->out_fifo = NULL;

264 ff_audio_convert_free(&avr->ac_in);

265 ff_audio_convert_free(&avr->ac_out);

266 ff_audio_resample_free(&avr->resample);

267 ff_audio_mix_free(&avr->am);

268 av_freep(&avr->mix_matrix);

269

270 avr->use_channel_map = 0;

271 }

272

273 void avresample_free(AVAudioResampleContext **avr)

274 {

275 if (!*avr)

276 return;

277 avresample_close(*avr);

278 av_opt_free(*avr);

279 av_freep(avr);

280 }

281

282 static int handle_buffered_output(AVAudioResampleContext *avr,

283 AudioData *output, AudioData *converted)

284 {

285 int ret;

286

287 if (!output || av_audio_fifo_size(avr->out_fifo) > 0 ||

288 (converted && output->allocated_samples < converted->nb_samples)) {

289 if (converted) {

290 /* if there are any samples in the output FIFO or if the

291 user-supplied output buffer is not large enough for all samples,

292 we add to the output FIFO */

293 av_dlog(avr, "[FIFO] add %s to out_fifo\n", converted->name);

294 ret = ff_audio_data_add_to_fifo(avr->out_fifo, converted, 0,

295 converted->nb_samples);

296 if (ret < 0)

297 return ret;

298 }

299

300 /* if the user specified an output buffer, read samples from the output

301 FIFO to the user output */

302 if (output && output->allocated_samples > 0) {

303 av_dlog(avr, "[FIFO] read from out_fifo to output\n");

304 av_dlog(avr, "[end conversion]\n");

305 return ff_audio_data_read_from_fifo(avr->out_fifo, output,

306 output->allocated_samples);

307 }

308 } else if (converted) {

309 /* copy directly to output if it is large enough or there is not any

310 data in the output FIFO */

311 av_dlog(avr, "[copy] %s to output\n", converted->name);

312 output->nb_samples = 0;

313 ret = ff_audio_data_copy(output, converted,

314 avr->remap_point == REMAP_OUT_COPY ?

315 &avr->ch_map_info : NULL);

316 if (ret < 0)

317 return ret;

318 av_dlog(avr, "[end conversion]\n");

319 return output->nb_samples;

320 }

321 av_dlog(avr, "[end conversion]\n");

322 return 0;

323 }

324

325 int attribute_align_arg avresample_convert(AVAudioResampleContext *avr,

326 uint8_t **output, int out_plane_size,

327 int out_samples, uint8_t **input,

328 int in_plane_size, int in_samples)

329 {

330 AudioData input_buffer;

331 AudioData output_buffer;

332 AudioData *current_buffer;

333 int ret, direct_output;

334

335 /* reset internal buffers */

336 if (avr->in_buffer) {

337 avr->in_buffer->nb_samples = 0;

338 ff_audio_data_set_channels(avr->in_buffer,

339 avr->in_buffer->allocated_channels);

340 }

341 if (avr->resample_out_buffer) {

342 avr->resample_out_buffer->nb_samples = 0;

343 ff_audio_data_set_channels(avr->resample_out_buffer,

344 avr->resample_out_buffer->allocated_channels);

345 }

346 if (avr->out_buffer) {

347 avr->out_buffer->nb_samples = 0;

348 ff_audio_data_set_channels(avr->out_buffer,

349 avr->out_buffer->allocated_channels);

350 }

351

352 av_dlog(avr, "[start conversion]\n");

353

354 /* initialize output_buffer with output data */

355 direct_output = output && av_audio_fifo_size(avr->out_fifo) == 0;

356 if (output) {

357 ret = ff_audio_data_init(&output_buffer, output, out_plane_size,

358 avr->out_channels, out_samples,

359 avr->out_sample_fmt, 0, "output");

360 if (ret < 0)

361 return ret;

362 output_buffer.nb_samples = 0;

363 }

364

365 if (input) {

366 /* initialize input_buffer with input data */

367 ret = ff_audio_data_init(&input_buffer, input, in_plane_size,

368 avr->in_channels, in_samples,

369 avr->in_sample_fmt, 1, "input");

370 if (ret < 0)

371 return ret;

372 current_buffer = &input_buffer;

373

374 if (avr->upmix_needed && !avr->in_convert_needed && !avr->resample_needed &&

375 !avr->out_convert_needed && direct_output && out_samples >= in_samples) {

376 /* in some rare cases we can copy input to output and upmix

377 directly in the output buffer */

378 av_dlog(avr, "[copy] %s to output\n", current_buffer->name);

379 ret = ff_audio_data_copy(&output_buffer, current_buffer,

380 avr->remap_point == REMAP_OUT_COPY ?

381 &avr->ch_map_info : NULL);

382 if (ret < 0)

383 return ret;

384 current_buffer = &output_buffer;

385 } else if (avr->remap_point == REMAP_OUT_COPY &&

386 (!direct_output || out_samples < in_samples)) {

387 /* if remapping channels during output copy, we may need to

388 * use an intermediate buffer in order to remap before adding

389 * samples to the output fifo */

390 av_dlog(avr, "[copy] %s to out_buffer\n", current_buffer->name);

391 ret = ff_audio_data_copy(avr->out_buffer, current_buffer,

392 &avr->ch_map_info);

393 if (ret < 0)

394 return ret;

395 current_buffer = avr->out_buffer;

396 } else if (avr->in_copy_needed || avr->in_convert_needed) {

397 /* if needed, copy or convert input to in_buffer, and downmix if

398 applicable */

399 if (avr->in_convert_needed) {

400 ret = ff_audio_data_realloc(avr->in_buffer,

401 current_buffer->nb_samples);

402 if (ret < 0)

403 return ret;

404 av_dlog(avr, "[convert] %s to in_buffer\n", current_buffer->name);

405 ret = ff_audio_convert(avr->ac_in, avr->in_buffer,

406 current_buffer);

407 if (ret < 0)

408 return ret;

409 } else {

410 av_dlog(avr, "[copy] %s to in_buffer\n", current_buffer->name);

411 ret = ff_audio_data_copy(avr->in_buffer, current_buffer,

412 avr->remap_point == REMAP_IN_COPY ?

413 &avr->ch_map_info : NULL);

414 if (ret < 0)

415 return ret;

416 }

417 ff_audio_data_set_channels(avr->in_buffer, avr->in_channels);

418 if (avr->downmix_needed) {

419 av_dlog(avr, "[downmix] in_buffer\n");

420 ret = ff_audio_mix(avr->am, avr->in_buffer);

421 if (ret < 0)

422 return ret;

423 }

424 current_buffer = avr->in_buffer;

425 }

426 } else {

427 /* flush resampling buffer and/or output FIFO if input is NULL */

428 if (!avr->resample_needed)

429 return handle_buffered_output(avr, output ? &output_buffer : NULL,

430 NULL);

431 current_buffer = NULL;

432 }

433

434 if (avr->resample_needed) {

435 AudioData *resample_out;

436

437 if (!avr->out_convert_needed && direct_output && out_samples > 0)

438 resample_out = &output_buffer;

439 else

440 resample_out = avr->resample_out_buffer;

441 av_dlog(avr, "[resample] %s to %s\n", current_buffer->name,

442 resample_out->name);

443 ret = ff_audio_resample(avr->resample, resample_out,

444 current_buffer);

445 if (ret < 0)

446 return ret;

447

448 /* if resampling did not produce any samples, just return 0 */

449 if (resample_out->nb_samples == 0) {

450 av_dlog(avr, "[end conversion]\n");

451 return 0;

452 }

453

454 current_buffer = resample_out;

455 }

456

457 if (avr->upmix_needed) {

458 av_dlog(avr, "[upmix] %s\n", current_buffer->name);

459 ret = ff_audio_mix(avr->am, current_buffer);

460 if (ret < 0)

461 return ret;

462 }

463

464 /* if we resampled or upmixed directly to output, return here */

465 if (current_buffer == &output_buffer) {

466 av_dlog(avr, "[end conversion]\n");

467 return current_buffer->nb_samples;

468 }

469

470 if (avr->out_convert_needed) {

471 if (direct_output && out_samples >= current_buffer->nb_samples) {

472 /* convert directly to output */

473 av_dlog(avr, "[convert] %s to output\n", current_buffer->name);

474 ret = ff_audio_convert(avr->ac_out, &output_buffer, current_buffer);

475 if (ret < 0)

476 return ret;

477

478 av_dlog(avr, "[end conversion]\n");

479 return output_buffer.nb_samples;

480 } else {

481 ret = ff_audio_data_realloc(avr->out_buffer,

482 current_buffer->nb_samples);

483 if (ret < 0)

484 return ret;

485 av_dlog(avr, "[convert] %s to out_buffer\n", current_buffer->name);

486 ret = ff_audio_convert(avr->ac_out, avr->out_buffer,

487 current_buffer);

488 if (ret < 0)

489 return ret;

490 current_buffer = avr->out_buffer;

491 }

492 }

493

494 return handle_buffered_output(avr, output ? &output_buffer : NULL,

495 current_buffer);

496 }

497

498 int avresample_get_matrix(AVAudioResampleContext *avr, double *matrix,

499 int stride)

500 {

501 int in_channels, out_channels, i, o;

502

503 if (avr->am)

504 return ff_audio_mix_get_matrix(avr->am, matrix, stride);

505

506 in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);

507 out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);

508

509 if ( in_channels <= 0 || in_channels > AVRESAMPLE_MAX_CHANNELS ||

510 out_channels <= 0 || out_channels > AVRESAMPLE_MAX_CHANNELS) {

511 av_log(avr, AV_LOG_ERROR, "Invalid channel layouts\n");

512 return AVERROR(EINVAL);

513 }

514

515 if (!avr->mix_matrix) {

516 av_log(avr, AV_LOG_ERROR, "matrix is not set\n");

517 return AVERROR(EINVAL);

518 }

519

520 for (o = 0; o < out_channels; o++)

521 for (i = 0; i < in_channels; i++)

522 matrix[o * stride + i] = avr->mix_matrix[o * in_channels + i];

523

524 return 0;

525 }

526

527 int avresample_set_matrix(AVAudioResampleContext *avr, const double *matrix,

528 int stride)

529 {

530 int in_channels, out_channels, i, o;

531

532 if (avr->am)

533 return ff_audio_mix_set_matrix(avr->am, matrix, stride);

534

535 in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);

536 out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);

537

538 if ( in_channels <= 0 || in_channels > AVRESAMPLE_MAX_CHANNELS ||

539 out_channels <= 0 || out_channels > AVRESAMPLE_MAX_CHANNELS) {

540 av_log(avr, AV_LOG_ERROR, "Invalid channel layouts\n");

541 return AVERROR(EINVAL);

542 }

543

544 if (avr->mix_matrix)

545 av_freep(&avr->mix_matrix);

546 avr->mix_matrix = av_malloc(in_channels * out_channels *

547 sizeof(*avr->mix_matrix));

548 if (!avr->mix_matrix)

549 return AVERROR(ENOMEM);

550

551 for (o = 0; o < out_channels; o++)

552 for (i = 0; i < in_channels; i++)

553 avr->mix_matrix[o * in_channels + i] = matrix[o * stride + i];

554

555 return 0;

556 }

557

558 int avresample_set_channel_mapping(AVAudioResampleContext *avr,

559 const int *channel_map)

560 {

561 ChannelMapInfo *info = &avr->ch_map_info;

562 int in_channels, ch, i;

563

564 in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);

565 if (in_channels <= 0 || in_channels > AVRESAMPLE_MAX_CHANNELS) {

566 av_log(avr, AV_LOG_ERROR, "Invalid input channel layout\n");

567 return AVERROR(EINVAL);

568 }

569

570 memset(info, 0, sizeof(*info));

571 memset(info->input_map, -1, sizeof(info->input_map));

572

573 for (ch = 0; ch < in_channels; ch++) {

574 if (channel_map[ch] >= in_channels) {

575 av_log(avr, AV_LOG_ERROR, "Invalid channel map\n");

576 return AVERROR(EINVAL);

577 }

578 if (channel_map[ch] < 0) {

579 info->channel_zero[ch] = 1;

580 info->channel_map[ch] = -1;

581 info->do_zero = 1;

582 } else if (info->input_map[channel_map[ch]] >= 0) {

583 info->channel_copy[ch] = info->input_map[channel_map[ch]];

584 info->channel_map[ch] = -1;

585 info->do_copy = 1;

586 } else {

587 info->channel_map[ch] = channel_map[ch];

588 info->input_map[channel_map[ch]] = ch;

589 info->do_remap = 1;

590 }

591 }

592 /* Fill-in unmapped input channels with unmapped output channels.

593 This is used when remapping during conversion from interleaved to

594 planar format. */

595 for (ch = 0, i = 0; ch < in_channels && i < in_channels; ch++, i++) {

596 while (ch < in_channels && info->input_map[ch] >= 0)

597 ch++;

598 while (i < in_channels && info->channel_map[i] >= 0)

599 i++;

600 if (ch >= in_channels || i >= in_channels)

601 break;

602 info->input_map[ch] = i;

603 }

604

605 avr->use_channel_map = 1;

606 return 0;

607 }

608

609 int avresample_available(AVAudioResampleContext *avr)

610 {

611 return av_audio_fifo_size(avr->out_fifo);

612 }

613

614 int avresample_read(AVAudioResampleContext *avr, uint8_t **output, int nb_samples)

615 {

616 if (!output)

617 return av_audio_fifo_drain(avr->out_fifo, nb_samples);

618 return av_audio_fifo_read(avr->out_fifo, (void**)output, nb_samples);

619 }

620

621 unsigned avresample_version(void)

622 {

623 return LIBAVRESAMPLE_VERSION_INT;

624 }

625

626 const char *avresample_license(void)

627 {

628 #define LICENSE_PREFIX "libavresample license: "

629 return LICENSE_PREFIX FFMPEG_LICENSE + sizeof(LICENSE_PREFIX) - 1;

630 }

631

632 const char *avresample_configuration(void)

633 {

634 return FFMPEG_CONFIGURATION;

635 }

Generated on Sat May 25 2013 04:01:11 for FFmpeg by doxygen 1.8.2