FFmpeg/libavfilter/audio.c

98 lines
3.2 KiB
C

/*
* Copyright (c) Stefano Sabatini | stefasab at gmail.com
* Copyright (c) S.N. Hemanth Meenakshisundaram | smeenaks at ucsd.edu
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/avassert.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "audio.h"
#include "avfilter.h"
#include "internal.h"
#define BUFFER_ALIGN 0
AVFrame *ff_null_get_audio_buffer(AVFilterLink *link, int nb_samples)
{
return ff_get_audio_buffer(link->dst->outputs[0], nb_samples);
}
AVFrame *ff_default_get_audio_buffer(AVFilterLink *link, int nb_samples)
{
AVFrame *frame = NULL;
int channels = link->channels;
av_assert0(channels == av_get_channel_layout_nb_channels(link->channel_layout) || !av_get_channel_layout_nb_channels(link->channel_layout));
if (!link->frame_pool) {
link->frame_pool = ff_frame_pool_audio_init(av_buffer_allocz, channels,
nb_samples, link->format, BUFFER_ALIGN);
if (!link->frame_pool)
return NULL;
} else {
int pool_channels = 0;
int pool_nb_samples = 0;
int pool_align = 0;
enum AVSampleFormat pool_format = AV_SAMPLE_FMT_NONE;
if (ff_frame_pool_get_audio_config(link->frame_pool,
&pool_channels, &pool_nb_samples,
&pool_format, &pool_align) < 0) {
return NULL;
}
if (pool_channels != channels || pool_nb_samples < nb_samples ||
pool_format != link->format || pool_align != BUFFER_ALIGN) {
ff_frame_pool_uninit((FFFramePool **)&link->frame_pool);
link->frame_pool = ff_frame_pool_audio_init(av_buffer_allocz, channels,
nb_samples, link->format, BUFFER_ALIGN);
if (!link->frame_pool)
return NULL;
}
}
frame = ff_frame_pool_get(link->frame_pool);
if (!frame)
return NULL;
frame->nb_samples = nb_samples;
frame->channel_layout = link->channel_layout;
frame->sample_rate = link->sample_rate;
av_samples_set_silence(frame->extended_data, 0, nb_samples, channels, link->format);
return frame;
}
AVFrame *ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
{
AVFrame *ret = NULL;
if (link->dstpad->get_audio_buffer)
ret = link->dstpad->get_audio_buffer(link, nb_samples);
if (!ret)
ret = ff_default_get_audio_buffer(link, nb_samples);
return ret;
}