2 * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
4 * This file is part of FFmpeg.
6 * FFmpeg 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.
11 * FFmpeg 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.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #include "libavutil/common.h"
22 #include "libavutil/dict.h"
23 // #include "libavutil/error.h"
24 #include "libavutil/frame.h"
25 #include "libavutil/log.h"
26 #include "libavutil/mem.h"
27 #include "libavutil/opt.h"
29 #include "avresample.h"
31 #include "audio_data.h"
32 #include "audio_convert.h"
33 #include "audio_mix.h"
36 int avresample_open(AVAudioResampleContext *avr)
40 if (avresample_is_open(avr)) {
41 av_log(avr, AV_LOG_ERROR, "The resampling context is already open.\n");
42 return AVERROR(EINVAL);
45 /* set channel mixing parameters */
46 avr->in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);
47 if (avr->in_channels <= 0 || avr->in_channels > AVRESAMPLE_MAX_CHANNELS) {
48 av_log(avr, AV_LOG_ERROR, "Invalid input channel layout: %"PRIu64"\n",
49 avr->in_channel_layout);
50 return AVERROR(EINVAL);
52 avr->out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);
53 if (avr->out_channels <= 0 || avr->out_channels > AVRESAMPLE_MAX_CHANNELS) {
54 av_log(avr, AV_LOG_ERROR, "Invalid output channel layout: %"PRIu64"\n",
55 avr->out_channel_layout);
56 return AVERROR(EINVAL);
58 avr->resample_channels = FFMIN(avr->in_channels, avr->out_channels);
59 avr->downmix_needed = avr->in_channels > avr->out_channels;
60 avr->upmix_needed = avr->out_channels > avr->in_channels ||
61 (!avr->downmix_needed && (avr->mix_matrix ||
62 avr->in_channel_layout != avr->out_channel_layout));
63 avr->mixing_needed = avr->downmix_needed || avr->upmix_needed;
65 /* set resampling parameters */
66 avr->resample_needed = avr->in_sample_rate != avr->out_sample_rate ||
67 avr->force_resampling;
69 /* select internal sample format if not specified by the user */
70 if (avr->internal_sample_fmt == AV_SAMPLE_FMT_NONE &&
71 (avr->mixing_needed || avr->resample_needed)) {
72 enum AVSampleFormat in_fmt = av_get_planar_sample_fmt(avr->in_sample_fmt);
73 enum AVSampleFormat out_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);
74 int max_bps = FFMAX(av_get_bytes_per_sample(in_fmt),
75 av_get_bytes_per_sample(out_fmt));
77 avr->internal_sample_fmt = AV_SAMPLE_FMT_S16P;
78 } else if (avr->mixing_needed) {
79 avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;
82 if (in_fmt == AV_SAMPLE_FMT_S32P ||
83 out_fmt == AV_SAMPLE_FMT_S32P) {
84 if (in_fmt == AV_SAMPLE_FMT_FLTP ||
85 out_fmt == AV_SAMPLE_FMT_FLTP) {
86 /* if one is s32 and the other is flt, use dbl */
87 avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;
89 /* if one is s32 and the other is s32, s16, or u8, use s32 */
90 avr->internal_sample_fmt = AV_SAMPLE_FMT_S32P;
93 /* if one is flt and the other is flt, s16 or u8, use flt */
94 avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;
97 /* if either is dbl, use dbl */
98 avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;
101 av_log(avr, AV_LOG_DEBUG, "Using %s as internal sample format\n",
102 av_get_sample_fmt_name(avr->internal_sample_fmt));
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 !ff_sample_fmt_is_planar(avr->out_sample_fmt, avr->out_channels)) {
109 avr->internal_sample_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);
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;
116 avr->in_convert_needed = avr->use_channel_map &&
117 !ff_sample_fmt_is_planar(avr->out_sample_fmt, avr->out_channels);
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;
122 avr->out_convert_needed = avr->in_sample_fmt != avr->out_sample_fmt;
124 avr->in_copy_needed = !avr->in_convert_needed && (avr->mixing_needed ||
125 (avr->use_channel_map && avr->resample_needed));
127 if (avr->use_channel_map) {
128 if (avr->in_copy_needed) {
129 avr->remap_point = REMAP_IN_COPY;
130 av_log(avr, AV_LOG_TRACE, "remap channels during in_copy\n");
131 } else if (avr->in_convert_needed) {
132 avr->remap_point = REMAP_IN_CONVERT;
133 av_log(avr, AV_LOG_TRACE, "remap channels during in_convert\n");
134 } else if (avr->out_convert_needed) {
135 avr->remap_point = REMAP_OUT_CONVERT;
136 av_log(avr, AV_LOG_TRACE, "remap channels during out_convert\n");
138 avr->remap_point = REMAP_OUT_COPY;
139 av_log(avr, AV_LOG_TRACE, "remap channels during out_copy\n");
145 av_log(avr, AV_LOG_TRACE, "output map: ");
146 if (avr->ch_map_info.do_remap)
147 for (ch = 0; ch < avr->in_channels; ch++)
148 av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.channel_map[ch]);
150 av_log(avr, AV_LOG_TRACE, "n/a");
151 av_log(avr, AV_LOG_TRACE, "\n");
152 av_log(avr, AV_LOG_TRACE, "copy map: ");
153 if (avr->ch_map_info.do_copy)
154 for (ch = 0; ch < avr->in_channels; ch++)
155 av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.channel_copy[ch]);
157 av_log(avr, AV_LOG_TRACE, "n/a");
158 av_log(avr, AV_LOG_TRACE, "\n");
159 av_log(avr, AV_LOG_TRACE, "zero map: ");
160 if (avr->ch_map_info.do_zero)
161 for (ch = 0; ch < avr->in_channels; ch++)
162 av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.channel_zero[ch]);
164 av_log(avr, AV_LOG_TRACE, "n/a");
165 av_log(avr, AV_LOG_TRACE, "\n");
166 av_log(avr, AV_LOG_TRACE, "input map: ");
167 for (ch = 0; ch < avr->in_channels; ch++)
168 av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.input_map[ch]);
169 av_log(avr, AV_LOG_TRACE, "\n");
173 avr->remap_point = REMAP_NONE;
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,
180 if (!avr->in_buffer) {
181 ret = AVERROR(EINVAL);
185 if (avr->resample_needed) {
186 avr->resample_out_buffer = ff_audio_data_alloc(avr->out_channels,
187 1024, avr->internal_sample_fmt,
188 "resample_out_buffer");
189 if (!avr->resample_out_buffer) {
190 ret = AVERROR(EINVAL);
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);
202 avr->out_fifo = av_audio_fifo_alloc(avr->out_sample_fmt, avr->out_channels,
204 if (!avr->out_fifo) {
205 ret = AVERROR(ENOMEM);
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,
214 avr->remap_point == REMAP_IN_CONVERT);
216 ret = AVERROR(ENOMEM);
220 if (avr->out_convert_needed) {
221 enum AVSampleFormat src_fmt;
222 if (avr->in_convert_needed)
223 src_fmt = avr->internal_sample_fmt;
225 src_fmt = avr->in_sample_fmt;
226 avr->ac_out = ff_audio_convert_alloc(avr, avr->out_sample_fmt, src_fmt,
228 avr->out_sample_rate,
229 avr->remap_point == REMAP_OUT_CONVERT);
231 ret = AVERROR(ENOMEM);
235 if (avr->resample_needed) {
236 avr->resample = ff_audio_resample_init(avr);
237 if (!avr->resample) {
238 ret = AVERROR(ENOMEM);
242 if (avr->mixing_needed) {
243 avr->am = ff_audio_mix_alloc(avr);
245 ret = AVERROR(ENOMEM);
253 avresample_close(avr);
257 int avresample_is_open(AVAudioResampleContext *avr)
259 return !!avr->out_fifo;
262 void avresample_close(AVAudioResampleContext *avr)
264 ff_audio_data_free(&avr->in_buffer);
265 ff_audio_data_free(&avr->resample_out_buffer);
266 ff_audio_data_free(&avr->out_buffer);
267 av_audio_fifo_free(avr->out_fifo);
268 avr->out_fifo = NULL;
269 ff_audio_convert_free(&avr->ac_in);
270 ff_audio_convert_free(&avr->ac_out);
271 ff_audio_resample_free(&avr->resample);
272 ff_audio_mix_free(&avr->am);
273 av_freep(&avr->mix_matrix);
275 avr->use_channel_map = 0;
278 void avresample_free(AVAudioResampleContext **avr)
282 avresample_close(*avr);
287 static int handle_buffered_output(AVAudioResampleContext *avr,
288 AudioData *output, AudioData *converted)
292 if (!output || av_audio_fifo_size(avr->out_fifo) > 0 ||
293 (converted && output->allocated_samples < converted->nb_samples)) {
295 /* if there are any samples in the output FIFO or if the
296 user-supplied output buffer is not large enough for all samples,
297 we add to the output FIFO */
298 av_log(avr, AV_LOG_TRACE, "[FIFO] add %s to out_fifo\n", converted->name);
299 ret = ff_audio_data_add_to_fifo(avr->out_fifo, converted, 0,
300 converted->nb_samples);
305 /* if the user specified an output buffer, read samples from the output
306 FIFO to the user output */
307 if (output && output->allocated_samples > 0) {
308 av_log(avr, AV_LOG_TRACE, "[FIFO] read from out_fifo to output\n");
309 av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
310 return ff_audio_data_read_from_fifo(avr->out_fifo, output,
311 output->allocated_samples);
313 } else if (converted) {
314 /* copy directly to output if it is large enough or there is not any
315 data in the output FIFO */
316 av_log(avr, AV_LOG_TRACE, "[copy] %s to output\n", converted->name);
317 output->nb_samples = 0;
318 ret = ff_audio_data_copy(output, converted,
319 avr->remap_point == REMAP_OUT_COPY ?
320 &avr->ch_map_info : NULL);
323 av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
324 return output->nb_samples;
326 av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
330 int attribute_align_arg avresample_convert(AVAudioResampleContext *avr,
331 uint8_t **output, int out_plane_size,
333 uint8_t * const *input,
334 int in_plane_size, int in_samples)
336 AudioData input_buffer;
337 AudioData output_buffer;
338 AudioData *current_buffer;
339 int ret, direct_output;
341 /* reset internal buffers */
342 if (avr->in_buffer) {
343 avr->in_buffer->nb_samples = 0;
344 ff_audio_data_set_channels(avr->in_buffer,
345 avr->in_buffer->allocated_channels);
347 if (avr->resample_out_buffer) {
348 avr->resample_out_buffer->nb_samples = 0;
349 ff_audio_data_set_channels(avr->resample_out_buffer,
350 avr->resample_out_buffer->allocated_channels);
352 if (avr->out_buffer) {
353 avr->out_buffer->nb_samples = 0;
354 ff_audio_data_set_channels(avr->out_buffer,
355 avr->out_buffer->allocated_channels);
358 av_log(avr, AV_LOG_TRACE, "[start conversion]\n");
360 /* initialize output_buffer with output data */
361 direct_output = output && av_audio_fifo_size(avr->out_fifo) == 0;
363 ret = ff_audio_data_init(&output_buffer, output, out_plane_size,
364 avr->out_channels, out_samples,
365 avr->out_sample_fmt, 0, "output");
368 output_buffer.nb_samples = 0;
372 /* initialize input_buffer with input data */
373 ret = ff_audio_data_init(&input_buffer, input, in_plane_size,
374 avr->in_channels, in_samples,
375 avr->in_sample_fmt, 1, "input");
378 current_buffer = &input_buffer;
380 if (avr->upmix_needed && !avr->in_convert_needed && !avr->resample_needed &&
381 !avr->out_convert_needed && direct_output && out_samples >= in_samples) {
382 /* in some rare cases we can copy input to output and upmix
383 directly in the output buffer */
384 av_log(avr, AV_LOG_TRACE, "[copy] %s to output\n", current_buffer->name);
385 ret = ff_audio_data_copy(&output_buffer, current_buffer,
386 avr->remap_point == REMAP_OUT_COPY ?
387 &avr->ch_map_info : NULL);
390 current_buffer = &output_buffer;
391 } else if (avr->remap_point == REMAP_OUT_COPY &&
392 (!direct_output || out_samples < in_samples)) {
393 /* if remapping channels during output copy, we may need to
394 * use an intermediate buffer in order to remap before adding
395 * samples to the output fifo */
396 av_log(avr, AV_LOG_TRACE, "[copy] %s to out_buffer\n", current_buffer->name);
397 ret = ff_audio_data_copy(avr->out_buffer, current_buffer,
401 current_buffer = avr->out_buffer;
402 } else if (avr->in_copy_needed || avr->in_convert_needed) {
403 /* if needed, copy or convert input to in_buffer, and downmix if
405 if (avr->in_convert_needed) {
406 ret = ff_audio_data_realloc(avr->in_buffer,
407 current_buffer->nb_samples);
410 av_log(avr, AV_LOG_TRACE, "[convert] %s to in_buffer\n", current_buffer->name);
411 ret = ff_audio_convert(avr->ac_in, avr->in_buffer,
416 av_log(avr, AV_LOG_TRACE, "[copy] %s to in_buffer\n", current_buffer->name);
417 ret = ff_audio_data_copy(avr->in_buffer, current_buffer,
418 avr->remap_point == REMAP_IN_COPY ?
419 &avr->ch_map_info : NULL);
423 ff_audio_data_set_channels(avr->in_buffer, avr->in_channels);
424 if (avr->downmix_needed) {
425 av_log(avr, AV_LOG_TRACE, "[downmix] in_buffer\n");
426 ret = ff_audio_mix(avr->am, avr->in_buffer);
430 current_buffer = avr->in_buffer;
433 /* flush resampling buffer and/or output FIFO if input is NULL */
434 if (!avr->resample_needed)
435 return handle_buffered_output(avr, output ? &output_buffer : NULL,
437 current_buffer = NULL;
440 if (avr->resample_needed) {
441 AudioData *resample_out;
443 if (!avr->out_convert_needed && direct_output && out_samples > 0)
444 resample_out = &output_buffer;
446 resample_out = avr->resample_out_buffer;
447 av_log(avr, AV_LOG_TRACE, "[resample] %s to %s\n",
448 current_buffer ? current_buffer->name : "null",
450 ret = ff_audio_resample(avr->resample, resample_out,
455 /* if resampling did not produce any samples, just return 0 */
456 if (resample_out->nb_samples == 0) {
457 av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
461 current_buffer = resample_out;
464 if (avr->upmix_needed) {
465 av_log(avr, AV_LOG_TRACE, "[upmix] %s\n", current_buffer->name);
466 ret = ff_audio_mix(avr->am, current_buffer);
471 /* if we resampled or upmixed directly to output, return here */
472 if (current_buffer == &output_buffer) {
473 av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
474 return current_buffer->nb_samples;
477 if (avr->out_convert_needed) {
478 if (direct_output && out_samples >= current_buffer->nb_samples) {
479 /* convert directly to output */
480 av_log(avr, AV_LOG_TRACE, "[convert] %s to output\n", current_buffer->name);
481 ret = ff_audio_convert(avr->ac_out, &output_buffer, current_buffer);
485 av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
486 return output_buffer.nb_samples;
488 ret = ff_audio_data_realloc(avr->out_buffer,
489 current_buffer->nb_samples);
492 av_log(avr, AV_LOG_TRACE, "[convert] %s to out_buffer\n", current_buffer->name);
493 ret = ff_audio_convert(avr->ac_out, avr->out_buffer,
497 current_buffer = avr->out_buffer;
501 return handle_buffered_output(avr, output ? &output_buffer : NULL,
505 int avresample_config(AVAudioResampleContext *avr, AVFrame *out, AVFrame *in)
507 if (avresample_is_open(avr)) {
508 avresample_close(avr);
512 avr->in_channel_layout = in->channel_layout;
513 avr->in_sample_rate = in->sample_rate;
514 avr->in_sample_fmt = in->format;
518 avr->out_channel_layout = out->channel_layout;
519 avr->out_sample_rate = out->sample_rate;
520 avr->out_sample_fmt = out->format;
526 static int config_changed(AVAudioResampleContext *avr,
527 AVFrame *out, AVFrame *in)
532 if (avr->in_channel_layout != in->channel_layout ||
533 avr->in_sample_rate != in->sample_rate ||
534 avr->in_sample_fmt != in->format) {
535 ret |= AVERROR_INPUT_CHANGED;
540 if (avr->out_channel_layout != out->channel_layout ||
541 avr->out_sample_rate != out->sample_rate ||
542 avr->out_sample_fmt != out->format) {
543 ret |= AVERROR_OUTPUT_CHANGED;
550 static inline int convert_frame(AVAudioResampleContext *avr,
551 AVFrame *out, AVFrame *in)
554 uint8_t **out_data = NULL, **in_data = NULL;
555 int out_linesize = 0, in_linesize = 0;
556 int out_nb_samples = 0, in_nb_samples = 0;
559 out_data = out->extended_data;
560 out_linesize = out->linesize[0];
561 out_nb_samples = out->nb_samples;
565 in_data = in->extended_data;
566 in_linesize = in->linesize[0];
567 in_nb_samples = in->nb_samples;
570 ret = avresample_convert(avr, out_data, out_linesize,
572 in_data, in_linesize,
582 out->nb_samples = ret;
587 static inline int available_samples(AVFrame *out)
590 int bytes_per_sample = av_get_bytes_per_sample(out->format);
591 if (!bytes_per_sample)
592 return AVERROR(EINVAL);
594 samples = out->linesize[0] / bytes_per_sample;
595 if (av_sample_fmt_is_planar(out->format)) {
598 int channels = av_get_channel_layout_nb_channels(out->channel_layout);
599 return samples / channels;
603 int avresample_convert_frame(AVAudioResampleContext *avr,
604 AVFrame *out, AVFrame *in)
608 if (!avresample_is_open(avr)) {
609 if ((ret = avresample_config(avr, out, in)) < 0)
611 if ((ret = avresample_open(avr)) < 0)
615 // return as is or reconfigure for input changes?
616 if ((ret = config_changed(avr, out, in)))
621 if (!out->linesize[0]) {
622 out->nb_samples = avresample_get_out_samples(avr, in->nb_samples);
623 if ((ret = av_frame_get_buffer(out, 0)) < 0) {
625 avresample_close(avr);
629 if (!out->nb_samples)
630 out->nb_samples = available_samples(out);
634 return convert_frame(avr, out, in);
637 int avresample_get_matrix(AVAudioResampleContext *avr, double *matrix,
640 int in_channels, out_channels, i, o;
643 return ff_audio_mix_get_matrix(avr->am, matrix, stride);
645 in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);
646 out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);
648 if ( in_channels <= 0 || in_channels > AVRESAMPLE_MAX_CHANNELS ||
649 out_channels <= 0 || out_channels > AVRESAMPLE_MAX_CHANNELS) {
650 av_log(avr, AV_LOG_ERROR, "Invalid channel layouts\n");
651 return AVERROR(EINVAL);
654 if (!avr->mix_matrix) {
655 av_log(avr, AV_LOG_ERROR, "matrix is not set\n");
656 return AVERROR(EINVAL);
659 for (o = 0; o < out_channels; o++)
660 for (i = 0; i < in_channels; i++)
661 matrix[o * stride + i] = avr->mix_matrix[o * in_channels + i];
666 int avresample_set_matrix(AVAudioResampleContext *avr, const double *matrix,
669 int in_channels, out_channels, i, o;
672 return ff_audio_mix_set_matrix(avr->am, matrix, stride);
674 in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);
675 out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);
677 if ( in_channels <= 0 || in_channels > AVRESAMPLE_MAX_CHANNELS ||
678 out_channels <= 0 || out_channels > AVRESAMPLE_MAX_CHANNELS) {
679 av_log(avr, AV_LOG_ERROR, "Invalid channel layouts\n");
680 return AVERROR(EINVAL);
684 av_freep(&avr->mix_matrix);
685 avr->mix_matrix = av_malloc(in_channels * out_channels *
686 sizeof(*avr->mix_matrix));
687 if (!avr->mix_matrix)
688 return AVERROR(ENOMEM);
690 for (o = 0; o < out_channels; o++)
691 for (i = 0; i < in_channels; i++)
692 avr->mix_matrix[o * in_channels + i] = matrix[o * stride + i];
697 int avresample_set_channel_mapping(AVAudioResampleContext *avr,
698 const int *channel_map)
700 ChannelMapInfo *info = &avr->ch_map_info;
701 int in_channels, ch, i;
703 in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);
704 if (in_channels <= 0 || in_channels > AVRESAMPLE_MAX_CHANNELS) {
705 av_log(avr, AV_LOG_ERROR, "Invalid input channel layout\n");
706 return AVERROR(EINVAL);
709 memset(info, 0, sizeof(*info));
710 memset(info->input_map, -1, sizeof(info->input_map));
712 for (ch = 0; ch < in_channels; ch++) {
713 if (channel_map[ch] >= in_channels) {
714 av_log(avr, AV_LOG_ERROR, "Invalid channel map\n");
715 return AVERROR(EINVAL);
717 if (channel_map[ch] < 0) {
718 info->channel_zero[ch] = 1;
719 info->channel_map[ch] = -1;
721 } else if (info->input_map[channel_map[ch]] >= 0) {
722 info->channel_copy[ch] = info->input_map[channel_map[ch]];
723 info->channel_map[ch] = -1;
726 info->channel_map[ch] = channel_map[ch];
727 info->input_map[channel_map[ch]] = ch;
731 /* Fill-in unmapped input channels with unmapped output channels.
732 This is used when remapping during conversion from interleaved to
734 for (ch = 0, i = 0; ch < in_channels && i < in_channels; ch++, i++) {
735 while (ch < in_channels && info->input_map[ch] >= 0)
737 while (i < in_channels && info->channel_map[i] >= 0)
739 if (ch >= in_channels || i >= in_channels)
741 info->input_map[ch] = i;
744 avr->use_channel_map = 1;
748 int avresample_available(AVAudioResampleContext *avr)
750 return av_audio_fifo_size(avr->out_fifo);
753 int avresample_get_out_samples(AVAudioResampleContext *avr, int in_nb_samples)
755 int64_t samples = avresample_get_delay(avr) + (int64_t)in_nb_samples;
757 if (avr->resample_needed) {
758 samples = av_rescale_rnd(samples,
759 avr->out_sample_rate,
764 samples += avresample_available(avr);
766 if (samples > INT_MAX)
767 return AVERROR(EINVAL);
772 int avresample_read(AVAudioResampleContext *avr, uint8_t **output, int nb_samples)
775 return av_audio_fifo_drain(avr->out_fifo, nb_samples);
776 return av_audio_fifo_read(avr->out_fifo, (void**)output, nb_samples);
779 unsigned avresample_version(void)
781 return LIBAVRESAMPLE_VERSION_INT;
784 const char *avresample_license(void)
786 #define LICENSE_PREFIX "libavresample license: "
787 return LICENSE_PREFIX FFMPEG_LICENSE + sizeof(LICENSE_PREFIX) - 1;
790 const char *avresample_configuration(void)
792 return FFMPEG_CONFIGURATION;