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/*
* 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
*/
/* shared code for simple demux/decode tools */
#include <stdlib.h>
#include <string.h>
#include "decode_simple.h"
#include "libavformat/avformat.h"
#include "libavcodec/avcodec.h"
#include "libavcodec/packet.h"
#include "libavutil/dict.h"
#include "libavutil/error.h"
#include "libavutil/frame.h"
static int decode_read(DecodeContext *dc, int flush)
{
const int ret_done = flush ? AVERROR_EOF : AVERROR(EAGAIN);
int ret = 0;
while (ret >= 0 &&
(dc->max_frames == 0 || dc->decoder->frame_num < dc->max_frames)) {
ret = avcodec_receive_frame(dc->decoder, dc->frame);
if (ret < 0) {
if (ret == AVERROR_EOF) {
int err = dc->process_frame(dc, NULL);
if (err < 0)
return err;
}
return (ret == ret_done) ? 0 : ret;
}
ret = dc->process_frame(dc, dc->frame);
av_frame_unref(dc->frame);
if (ret < 0)
return ret;
if (dc->max_frames && dc->decoder->frame_num == dc->max_frames)
return 1;
}
return (dc->max_frames == 0 || dc->decoder->frame_num < dc->max_frames) ? 0 : 1;
}
int ds_run(DecodeContext *dc)
{
int ret;
ret = avcodec_open2(dc->decoder, NULL, &dc->decoder_opts);
if (ret < 0)
return ret;
while (ret >= 0) {
ret = av_read_frame(dc->demuxer, dc->pkt);
if (ret < 0)
goto flush;
if (dc->pkt->stream_index != dc->stream->index) {
av_packet_unref(dc->pkt);
continue;
}
ret = avcodec_send_packet(dc->decoder, dc->pkt);
if (ret < 0) {
fprintf(stderr, "Error decoding: %d\n", ret);
return ret;
}
av_packet_unref(dc->pkt);
ret = decode_read(dc, 0);
if (ret < 0) {
fprintf(stderr, "Error decoding: %d\n", ret);
return ret;
} else if (ret > 0)
return 0;
}
flush:
avcodec_send_packet(dc->decoder, NULL);
ret = decode_read(dc, 1);
if (ret < 0) {
fprintf(stderr, "Error flushing: %d\n", ret);
return ret;
}
return 0;
}
void ds_free(DecodeContext *dc)
{
av_dict_free(&dc->decoder_opts);
av_frame_free(&dc->frame);
av_packet_free(&dc->pkt);
avcodec_free_context(&dc->decoder);
avformat_close_input(&dc->demuxer);
}
int ds_open(DecodeContext *dc, const char *url, int stream_idx)
{
const AVCodec *codec;
int ret;
memset(dc, 0, sizeof(*dc));
dc->pkt = av_packet_alloc();
dc->frame = av_frame_alloc();
if (!dc->pkt || !dc->frame) {
ret = AVERROR(ENOMEM);
goto fail;
}
ret = avformat_open_input(&dc->demuxer, url, NULL, NULL);
if (ret < 0) {
fprintf(stderr, "Error opening input file: %d\n", ret);
return ret;
}
if (stream_idx < 0 || stream_idx >= dc->demuxer->nb_streams)
return AVERROR(EINVAL);
dc->stream = dc->demuxer->streams[stream_idx];
codec = avcodec_find_decoder(dc->stream->codecpar->codec_id);
if (!codec)
return AVERROR_DECODER_NOT_FOUND;
dc->decoder = avcodec_alloc_context3(codec);
if (!dc->decoder)
return AVERROR(ENOMEM);
return 0;
fail:
ds_free(dc);
return ret;
}
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