[FFmpeg-devel] [PATCH]concatdec: measure duration when it is not available

[Bodecs Bela]

Hi All,

This patch is a bug fix for a problem I faced recently.
There are cases when duration info is not available. e.g. reading an
mpegts file via a fifo file. But for concatenation this info is
mandatory to adjust next file timestamps. So we need to measure it to
have this value.

please include my patch in official ffmpeg tree.

thanks in advance,

best regards,

Bela Bodecs

>From 3512d551fbf9d93398373edb37e4e92158bf4227 Tue, 16 Feb 2016 00:10:55 +0100
From: Bela Bodecs <bode...@vivanet.hu>
Date: Tue, 16 Feb 2016 00:08:13 +0100
Subject: [PATCH] concatdec: measure duration when it is not available


There are cases when duration info is not available. e.g. reading an
mpegts file via a fifo file. But for concatenation this info is
mandatory to adjust next file timestamps. So we need to measure it to
have this value.
Signed-off-by: Bela Bodecs <bode...@vivanet.hu>
diff --git a/libavformat/concatdec.c b/libavformat/concatdec.c
index d226e15..68c4701 100644
--- a/libavformat/concatdec.c
+++ b/libavformat/concatdec.c
@@ -47,10 +47,11 @@
     ConcatStream *streams;
     int64_t inpoint;
     int64_t outpoint;
     AVDictionary *metadata;
     int nb_streams;
+    int64_t measured_duration;
 } ConcatFile;
 
 typedef struct {
     AVClass *class;
     ConcatFile *files;
@@ -478,11 +479,11 @@
 {
     ConcatContext *cat = avf->priv_data;
     unsigned fileno = cat->cur_file - cat->files;
 
     if (cat->cur_file->duration == AV_NOPTS_VALUE)
-        cat->cur_file->duration = cat->avf->duration - (cat->cur_file->file_inpoint - cat->cur_file->file_start_time);
+        cat->cur_file->duration = ((cat->avf->duration == AV_NOPTS_VALUE) ? cat->cur_file->measured_duration : cat->avf->duration) - (cat->cur_file->file_inpoint - cat->cur_file->file_start_time);
 
     if (++fileno >= cat->nb_files) {
         cat->eof = 1;
         return AVERROR_EOF;
     }
@@ -544,10 +545,11 @@
     ConcatContext *cat = avf->priv_data;
     int ret;
     int64_t delta;
     ConcatStream *cs;
     AVStream *st;
+    int64_t new_dur;
 
     if (cat->eof)
         return AVERROR_EOF;
 
     if (!cat->avf)
@@ -587,10 +589,14 @@
     av_log(avf, AV_LOG_DEBUG, "file:%d stream:%d pts:%s pts_time:%s dts:%s dts_time:%s",
            (unsigned)(cat->cur_file - cat->files), pkt->stream_index,
            av_ts2str(pkt->pts), av_ts2timestr(pkt->pts, &st->time_base),
            av_ts2str(pkt->dts), av_ts2timestr(pkt->dts, &st->time_base));
 
+    new_dur = av_rescale_q(pkt->pts + pkt->duration, cat->avf->streams[pkt->stream_index]->time_base, AV_TIME_BASE_Q) - cat->cur_file->file_inpoint;
+    if (cat->cur_file->measured_duration < new_dur)
+        cat->cur_file->measured_duration = new_dur;
+
     delta = av_rescale_q(cat->cur_file->start_time - cat->cur_file->file_inpoint,
                          AV_TIME_BASE_Q,
                          cat->avf->streams[pkt->stream_index]->time_base);
     if (pkt->pts != AV_NOPTS_VALUE)
         pkt->pts += delta;

_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel