/* * 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 "framepool.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;    int channel_layout_nb_channels = av_get_channel_layout_nb_channels(link->channel_layout);     av_assert0(channels == channel_layout_nb_channels || !channel_layout_nb_channels);     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_buffer.audio)        ret = link->dstpad->get_buffer.audio(link, nb_samples);     if (!ret)        ret = ff_default_get_audio_buffer(link, nb_samples);     return ret;}