FFmpeg源码剖析-框架：process_input()
2017-09-17 00:32
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process_input()函数位于ffmpeg.c
它的作用的从文件中读取一个packet,并解码；
/*
* 它是在open_input_file()->add_input_stream()中初始化的，
* Add all the streams from the given input file to the global
* list of input streams. */
* static void add_input_streams(OptionsContext *o, AVFormatContext *ic)
* {
* for (i = 0; i < ic->nb_streams; i++) {
* InputStream *ist = av_mallocz(sizeof(*ist));
*
* GROW_ARRAY(input_streams, nb_input_streams);
* input_streams[nb_input_streams - 1] = ist;
* }
*/
InputStream **input_streams = NULL;
/*
* Return
* - 0 -- one packet was read and processed
* - AVERROR(EAGAIN) -- no packets were available for selected file,
* this function should be called again
* - AVERROR_EOF -- this function should not be called again
*/
static int process_input(int file_index)
{
InputFile *ifile = input_files[file_index];
AVFormatContext *is;
InputStream *ist;
AVPacket pkt;
int ret, i, j;
int64_t duration;
int64_t pkt_dts;
is = ifile->ctx;
/* 读取一个packet(可以是视频的一帧，音频的多帧) */
ret = get_input_packet(ifile, &pkt);
reset_eagain();
ist = input_streams[ifile->ist_index + pkt.stream_index];
ist->data_size += pkt.size;
ist->nb_packets++;
if(!ist->wrap_correction_done && is->start_time != AV_NOPTS_VALUE && ist->st->pts_wrap_bits < 64){
int64_t stime, stime2;
// Correcting starttime based on the enabled streams
stime = av_rescale_q(is->start_time, AV_TIME_BASE_Q, ist->st->time_base);
stime2= stime + (1ULL<st->pts_wrap_bits);
ist->wrap_correction_done = 1;
if(stime2 > stime && pkt.dts != AV_NOPTS_VALUE && pkt.dts > stime + (1LL<<(ist->st->pts_wrap_bits-1))) {
pkt.dts -= 1ULL<st->pts_wrap_bits;
ist->wrap_correction_done = 0;
}
if(stime2 > stime && pkt.pts != AV_NOPTS_VALUE && pkt.pts > stime + (1LL<<(ist->st->pts_wrap_bits-1))) {
pkt.pts -= 1ULL<st->pts_wrap_bits;
ist->wrap_correction_done = 0;
}
}
/* 将packet中的时间戳转换成ffmpeg内部的时间戳 */
if (pkt.dts != AV_NOPTS_VALUE)
pkt.dts += av_rescale_q(ifile->ts_offset, AV_TIME_BASE_Q, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE)
pkt.pts += av_rescale_q(ifile->ts_offset, AV_TIME_BASE_Q, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE)
pkt.pts *= ist->ts_scale;
if (pkt.dts != AV_NOPTS_VALUE)
pkt.dts *= ist->ts_scale;
pkt_dts = av_rescale_q_rnd(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
if ((ist->dec_ctx->codec_type == AVMEDIA_TYPE_VIDEO ||
ist->dec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) &&
pkt_dts != AV_NOPTS_VALUE && ist->next_dts == AV_NOPTS_VALUE && !copy_ts
&& (is->iformat->flags & AVFMT_TS_DISCONT) && ifile->last_ts != AV_NOPTS_VALUE) {
int64_t delta = pkt_dts - ifile->last_ts;
if (delta < -1LL*dts_delta_threshold*AV_TIME_BASE ||
delta > 1LL*dts_delta_threshold*AV_TIME_BASE){
ifile->ts_offset -= delta;
av_log(NULL, AV_LOG_DEBUG,
"Inter stream timestamp discontinuity %"PRId64", new offset= %"PRId64"\n",
delta, ifile->ts_offset);
pkt.dts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE)
pkt.pts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
}
}
/* 计算出当前packet所包含的音频/视频帧在显示时要持续的时长 */
duration = av_rescale_q(ifile->duration, ifile->time_base, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE) {
pkt.pts += duration;
ist->max_pts = FFMAX(pkt.pts, ist->max_pts);
ist->min_pts = FFMIN(pkt.pts, ist->min_pts);
}
if (pkt.dts != AV_NOPTS_VALUE)
pkt.dts += duration;
pkt_dts = av_rescale_q_rnd(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
if ((ist->dec_ctx->codec_type == AVMEDIA_TYPE_VIDEO ||
ist->dec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) &&
pkt_dts != AV_NOPTS_VALUE && ist->next_dts != AV_NOPTS_VALUE &&
!copy_ts) {
int64_t delta = pkt_dts - ist->next_dts;
if (is->iformat->flags & AVFMT_TS_DISCONT) {
if (delta < -1LL*dts_delta_threshold*AV_TIME_BASE ||
delta > 1LL*dts_delta_threshold*AV_TIME_BASE ||
pkt_dts + AV_TIME_BASE/10 < FFMAX(ist->pts, ist->dts)) {
ifile->ts_offset -= delta;
av_log(NULL, AV_LOG_DEBUG,
"timestamp discontinuity %"PRId64", new offset= %"PRId64"\n",
delta, ifile->ts_offset);
pkt.dts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE)
pkt.pts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
}
} else {
if ( delta < -1LL*dts_error_threshold*AV_TIME_BASE ||
delta > 1LL*dts_error_threshold*AV_TIME_BASE) {
av_log(NULL, AV_LOG_WARNING, "DTS %"PRId64", next:%"PRId64" st:%d invalid dropping\n", pkt.dts, ist->next_dts, pkt.stream_index);
pkt.dts = AV_NOPTS_VALUE;
}
if (pkt.pts != AV_NOPTS_VALUE){
int64_t pkt_pts = av_rescale_q(pkt.pts, ist->st->time_base, AV_TIME_BASE_Q);
delta = pkt_pts - ist->next_dts;
if ( delta < -1LL*dts_error_threshold*AV_TIME_BASE ||
delta > 1LL*dts_error_threshold*AV_TIME_BASE) {
av_log(NULL, AV_LOG_WARNING, "PTS %"PRId64", next:%"PRId64" invalid dropping st:%d\n", pkt.pts, ist->next_dts, pkt.stream_index);
pkt.pts = AV_NOPTS_VALUE;
}
}
}
}
if (pkt.dts != AV_NOPTS_VALUE)
ifile->last_ts = av_rescale_q(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q);
sub2video_heartbeat(ist, pkt.pts);
/* 解码当前的这个packet */
process_input_packet(ist, &pkt, 0);
discard_packet:
av_packet_unref(&pkt);
return 0;
}
static int process_input_packet(InputStream *ist, const AVPacket *pkt, int no_eof)
{
int ret = 0, i;
int repeating = 0;
int eof_reached = 0;
AVPacket avpkt;
if (!ist->saw_first_ts) {
ist->dts = ist->st->avg_frame_rate.num ? - ist->dec_ctx->has_b_frames * AV_TIME_BASE / av_q2d(ist->st->avg_frame_rate) : 0;
ist->pts = 0;
if (pkt && pkt->pts != AV_NOPTS_VALUE && !ist->decoding_needed) {
ist->dts += av_rescale_q(pkt->pts, ist->st->time_base, AV_TIME_BASE_Q);
ist->pts = ist->dts; //unused but better to set it to a value thats not totally wrong
}
ist->saw_first_ts = 1;
}
if (ist->next_dts == AV_NOPTS_VALUE)
ist->next_dts = ist->dts;
if (ist->next_pts == AV_NOPTS_VALUE)
ist->next_pts = ist->pts;
if (!pkt) {
/* EOF handling */
av_init_packet(&avpkt);
avpkt.data = NULL;
avpkt.size = 0;
} else {
avpkt = *pkt;
}
if (pkt && pkt->dts != AV_NOPTS_VALUE) {
ist->next_dts = ist->dts = av_rescale_q(pkt->dts, ist->st->time_base, AV_TIME_BASE_Q);
if (ist->dec_ctx->codec_type != AVMEDIA_TYPE_VIDEO || !ist->decoding_needed)
ist->next_pts = ist->pts = ist->dts;
}
// while we have more to decode or while the decoder did output something on EOF
while (ist->decoding_needed) {
int duration = 0;
int got_output = 0;
ist->pts = ist->next_pts;
ist->dts = ist->next_dts;
/* 依据当前的packet是视频、音频还是数据，选择对应的解码器解码当前的packet */
switch (ist->dec_ctx->codec_type) {
case AVMEDIA_TYPE_AUDIO:
ret = decode_audio (ist, repeating ? NULL : &avpkt, &got_output);
break;
case AVMEDIA_TYPE_VIDEO:
ret = decode_video (ist, repeating ? NULL : &avpkt, &got_output, !pkt);
if (!repeating || !pkt || got_output) {
if (pkt && pkt->duration) {
duration = av_rescale_q(pkt->duration, ist->st->time_base, AV_TIME_BASE_Q);
} else if(ist->dec_ctx->framerate.num != 0 && ist->dec_ctx->framerate.den != 0) {
int ticks= av_stream_get_parser(ist->st) ? av_stream_get_parser(ist->st)->repeat_pict+1 : ist->dec_ctx->ticks_per_frame;
duration = ((int64_t)AV_TIME_BASE *
ist->dec_ctx->framerate.den * ticks) /
ist->dec_ctx->framerate.num / ist->dec_ctx->ticks_per_frame;
}
if(ist->dts != AV_NOPTS_VALUE && duration) {
ist->next_dts += duration;
}else
ist->next_dts = AV_NOPTS_VALUE;
}
if (got_output)
ist->next_pts += duration; //FIXME the duration is not correct in some cases
break;
case AVMEDIA_TYPE_SUBTITLE:
if (repeating)
break;
ret = transcode_subtitles(ist, &avpkt, &got_output);
if (!pkt && ret >= 0)
ret = AVERROR_EOF;
break;
default:
return -1;
}
if (ret == AVERROR_EOF) {
eof_reached = 1;
break;
}
if (ret < 0) {
av_log(NULL, AV_LOG_ERROR, "Error while decoding stream #%d:%d: %s\n",
ist->file_index, ist->st->index, av_err2str(ret));
if (exit_on_error)
exit_program(1);
// Decoding might not terminate if we're draining the decoder, and
// the decoder keeps returning an error.
// This should probably be considered a libavcodec issue.
// Sample: fate-vsynth1-dnxhd-720p-hr-lb
if (!pkt)
eof_reached = 1;
break;
}
if (!got_output)
break;
// During draining, we might get multiple output frames in this loop.
// ffmpeg.c does not drain the filter chain on configuration changes,
// which means if we send multiple frames at once to the filters, and
// one of those frames changes configuration, the buffered frames will
// be lost. This can upset certain FATE tests.
// Decode only 1 frame per call on EOF to appease these FATE tests.
// The ideal solution would be to rewrite decoding to use the new
// decoding API in a better way.
if (!pkt)
break;
repeating = 1;
}
/* after flushing, send an EOF on all the filter inputs attached to the stream */
/* except when looping we need to flush but not to send an EOF */
if (!pkt && ist->decoding_needed && eof_reached && !no_eof) {
int ret = send_filter_eof(ist);
if (ret < 0) {
av_log(NULL, AV_LOG_FATAL, "Error marking filters as finished\n");
exit_program(1);
}
}
/* handle stream copy */
...
for (i = 0; pkt && i < nb_output_streams; i++) {
OutputStream *ost = output_streams[i];
if (!check_output_constraints(ist, ost) || ost->encoding_needed)
continue;
do_streamcopy(ist, ost, pkt);
}
return !eof_reached;
}
1. 函数概述
它的作用的从文件中读取一个packet,并解码；
2. 函数调用结构图
3. 代码分析
/* * 它是在open_input_file()->add_input_stream()中初始化的，
* Add all the streams from the given input file to the global
* list of input streams. */
* static void add_input_streams(OptionsContext *o, AVFormatContext *ic)
* {
* for (i = 0; i < ic->nb_streams; i++) {
* InputStream *ist = av_mallocz(sizeof(*ist));
*
* GROW_ARRAY(input_streams, nb_input_streams);
* input_streams[nb_input_streams - 1] = ist;
* }
*/
InputStream **input_streams = NULL;
/*
* Return
* - 0 -- one packet was read and processed
* - AVERROR(EAGAIN) -- no packets were available for selected file,
* this function should be called again
* - AVERROR_EOF -- this function should not be called again
*/
static int process_input(int file_index)
{
InputFile *ifile = input_files[file_index];
AVFormatContext *is;
InputStream *ist;
AVPacket pkt;
int ret, i, j;
int64_t duration;
int64_t pkt_dts;
is = ifile->ctx;
/* 读取一个packet(可以是视频的一帧，音频的多帧) */
ret = get_input_packet(ifile, &pkt);
reset_eagain();
ist = input_streams[ifile->ist_index + pkt.stream_index];
ist->data_size += pkt.size;
ist->nb_packets++;
if(!ist->wrap_correction_done && is->start_time != AV_NOPTS_VALUE && ist->st->pts_wrap_bits < 64){
int64_t stime, stime2;
// Correcting starttime based on the enabled streams
stime = av_rescale_q(is->start_time, AV_TIME_BASE_Q, ist->st->time_base);
stime2= stime + (1ULL<st->pts_wrap_bits);
ist->wrap_correction_done = 1;
if(stime2 > stime && pkt.dts != AV_NOPTS_VALUE && pkt.dts > stime + (1LL<<(ist->st->pts_wrap_bits-1))) {
pkt.dts -= 1ULL<st->pts_wrap_bits;
ist->wrap_correction_done = 0;
}
if(stime2 > stime && pkt.pts != AV_NOPTS_VALUE && pkt.pts > stime + (1LL<<(ist->st->pts_wrap_bits-1))) {
pkt.pts -= 1ULL<st->pts_wrap_bits;
ist->wrap_correction_done = 0;
}
}
/* 将packet中的时间戳转换成ffmpeg内部的时间戳 */
if (pkt.dts != AV_NOPTS_VALUE)
pkt.dts += av_rescale_q(ifile->ts_offset, AV_TIME_BASE_Q, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE)
pkt.pts += av_rescale_q(ifile->ts_offset, AV_TIME_BASE_Q, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE)
pkt.pts *= ist->ts_scale;
if (pkt.dts != AV_NOPTS_VALUE)
pkt.dts *= ist->ts_scale;
pkt_dts = av_rescale_q_rnd(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
if ((ist->dec_ctx->codec_type == AVMEDIA_TYPE_VIDEO ||
ist->dec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) &&
pkt_dts != AV_NOPTS_VALUE && ist->next_dts == AV_NOPTS_VALUE && !copy_ts
&& (is->iformat->flags & AVFMT_TS_DISCONT) && ifile->last_ts != AV_NOPTS_VALUE) {
int64_t delta = pkt_dts - ifile->last_ts;
if (delta < -1LL*dts_delta_threshold*AV_TIME_BASE ||
delta > 1LL*dts_delta_threshold*AV_TIME_BASE){
ifile->ts_offset -= delta;
av_log(NULL, AV_LOG_DEBUG,
"Inter stream timestamp discontinuity %"PRId64", new offset= %"PRId64"\n",
delta, ifile->ts_offset);
pkt.dts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE)
pkt.pts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
}
}
/* 计算出当前packet所包含的音频/视频帧在显示时要持续的时长 */
duration = av_rescale_q(ifile->duration, ifile->time_base, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE) {
pkt.pts += duration;
ist->max_pts = FFMAX(pkt.pts, ist->max_pts);
ist->min_pts = FFMIN(pkt.pts, ist->min_pts);
}
if (pkt.dts != AV_NOPTS_VALUE)
pkt.dts += duration;
pkt_dts = av_rescale_q_rnd(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
if ((ist->dec_ctx->codec_type == AVMEDIA_TYPE_VIDEO ||
ist->dec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) &&
pkt_dts != AV_NOPTS_VALUE && ist->next_dts != AV_NOPTS_VALUE &&
!copy_ts) {
int64_t delta = pkt_dts - ist->next_dts;
if (is->iformat->flags & AVFMT_TS_DISCONT) {
if (delta < -1LL*dts_delta_threshold*AV_TIME_BASE ||
delta > 1LL*dts_delta_threshold*AV_TIME_BASE ||
pkt_dts + AV_TIME_BASE/10 < FFMAX(ist->pts, ist->dts)) {
ifile->ts_offset -= delta;
av_log(NULL, AV_LOG_DEBUG,
"timestamp discontinuity %"PRId64", new offset= %"PRId64"\n",
delta, ifile->ts_offset);
pkt.dts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
if (pkt.pts != AV_NOPTS_VALUE)
pkt.pts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
}
} else {
if ( delta < -1LL*dts_error_threshold*AV_TIME_BASE ||
delta > 1LL*dts_error_threshold*AV_TIME_BASE) {
av_log(NULL, AV_LOG_WARNING, "DTS %"PRId64", next:%"PRId64" st:%d invalid dropping\n", pkt.dts, ist->next_dts, pkt.stream_index);
pkt.dts = AV_NOPTS_VALUE;
}
if (pkt.pts != AV_NOPTS_VALUE){
int64_t pkt_pts = av_rescale_q(pkt.pts, ist->st->time_base, AV_TIME_BASE_Q);
delta = pkt_pts - ist->next_dts;
if ( delta < -1LL*dts_error_threshold*AV_TIME_BASE ||
delta > 1LL*dts_error_threshold*AV_TIME_BASE) {
av_log(NULL, AV_LOG_WARNING, "PTS %"PRId64", next:%"PRId64" invalid dropping st:%d\n", pkt.pts, ist->next_dts, pkt.stream_index);
pkt.pts = AV_NOPTS_VALUE;
}
}
}
}
if (pkt.dts != AV_NOPTS_VALUE)
ifile->last_ts = av_rescale_q(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q);
sub2video_heartbeat(ist, pkt.pts);
/* 解码当前的这个packet */
process_input_packet(ist, &pkt, 0);
discard_packet:
av_packet_unref(&pkt);
return 0;
}
4.1 process_input_packet()
/* pkt = NULL means EOF (needed to flush decoder buffers) */static int process_input_packet(InputStream *ist, const AVPacket *pkt, int no_eof)
{
int ret = 0, i;
int repeating = 0;
int eof_reached = 0;
AVPacket avpkt;
if (!ist->saw_first_ts) {
ist->dts = ist->st->avg_frame_rate.num ? - ist->dec_ctx->has_b_frames * AV_TIME_BASE / av_q2d(ist->st->avg_frame_rate) : 0;
ist->pts = 0;
if (pkt && pkt->pts != AV_NOPTS_VALUE && !ist->decoding_needed) {
ist->dts += av_rescale_q(pkt->pts, ist->st->time_base, AV_TIME_BASE_Q);
ist->pts = ist->dts; //unused but better to set it to a value thats not totally wrong
}
ist->saw_first_ts = 1;
}
if (ist->next_dts == AV_NOPTS_VALUE)
ist->next_dts = ist->dts;
if (ist->next_pts == AV_NOPTS_VALUE)
ist->next_pts = ist->pts;
if (!pkt) {
/* EOF handling */
av_init_packet(&avpkt);
avpkt.data = NULL;
avpkt.size = 0;
} else {
avpkt = *pkt;
}
if (pkt && pkt->dts != AV_NOPTS_VALUE) {
ist->next_dts = ist->dts = av_rescale_q(pkt->dts, ist->st->time_base, AV_TIME_BASE_Q);
if (ist->dec_ctx->codec_type != AVMEDIA_TYPE_VIDEO || !ist->decoding_needed)
ist->next_pts = ist->pts = ist->dts;
}
// while we have more to decode or while the decoder did output something on EOF
while (ist->decoding_needed) {
int duration = 0;
int got_output = 0;
ist->pts = ist->next_pts;
ist->dts = ist->next_dts;
/* 依据当前的packet是视频、音频还是数据，选择对应的解码器解码当前的packet */
switch (ist->dec_ctx->codec_type) {
case AVMEDIA_TYPE_AUDIO:
ret = decode_audio (ist, repeating ? NULL : &avpkt, &got_output);
break;
case AVMEDIA_TYPE_VIDEO:
ret = decode_video (ist, repeating ? NULL : &avpkt, &got_output, !pkt);
if (!repeating || !pkt || got_output) {
if (pkt && pkt->duration) {
duration = av_rescale_q(pkt->duration, ist->st->time_base, AV_TIME_BASE_Q);
} else if(ist->dec_ctx->framerate.num != 0 && ist->dec_ctx->framerate.den != 0) {
int ticks= av_stream_get_parser(ist->st) ? av_stream_get_parser(ist->st)->repeat_pict+1 : ist->dec_ctx->ticks_per_frame;
duration = ((int64_t)AV_TIME_BASE *
ist->dec_ctx->framerate.den * ticks) /
ist->dec_ctx->framerate.num / ist->dec_ctx->ticks_per_frame;
}
if(ist->dts != AV_NOPTS_VALUE && duration) {
ist->next_dts += duration;
}else
ist->next_dts = AV_NOPTS_VALUE;
}
if (got_output)
ist->next_pts += duration; //FIXME the duration is not correct in some cases
break;
case AVMEDIA_TYPE_SUBTITLE:
if (repeating)
break;
ret = transcode_subtitles(ist, &avpkt, &got_output);
if (!pkt && ret >= 0)
ret = AVERROR_EOF;
break;
default:
return -1;
}
if (ret == AVERROR_EOF) {
eof_reached = 1;
break;
}
if (ret < 0) {
av_log(NULL, AV_LOG_ERROR, "Error while decoding stream #%d:%d: %s\n",
ist->file_index, ist->st->index, av_err2str(ret));
if (exit_on_error)
exit_program(1);
// Decoding might not terminate if we're draining the decoder, and
// the decoder keeps returning an error.
// This should probably be considered a libavcodec issue.
// Sample: fate-vsynth1-dnxhd-720p-hr-lb
if (!pkt)
eof_reached = 1;
break;
}
if (!got_output)
break;
// During draining, we might get multiple output frames in this loop.
// ffmpeg.c does not drain the filter chain on configuration changes,
// which means if we send multiple frames at once to the filters, and
// one of those frames changes configuration, the buffered frames will
// be lost. This can upset certain FATE tests.
// Decode only 1 frame per call on EOF to appease these FATE tests.
// The ideal solution would be to rewrite decoding to use the new
// decoding API in a better way.
if (!pkt)
break;
repeating = 1;
}
/* after flushing, send an EOF on all the filter inputs attached to the stream */
/* except when looping we need to flush but not to send an EOF */
if (!pkt && ist->decoding_needed && eof_reached && !no_eof) {
int ret = send_filter_eof(ist);
if (ret < 0) {
av_log(NULL, AV_LOG_FATAL, "Error marking filters as finished\n");
exit_program(1);
}
}
/* handle stream copy */
...
for (i = 0; pkt && i < nb_output_streams; i++) {
OutputStream *ost = output_streams[i];
if (!check_output_constraints(ist, ost) || ost->encoding_needed)
continue;
do_streamcopy(ist, ost, pkt);
}
return !eof_reached;
}
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