timestamps generation improvement when parsing avi

patch by Joakim \ elupus chez ecce dot se /
original thread:
date: 03/19/2007 01:47 AM
subject: [Ffmpeg-devel] [RFC] Improvement for the odd timestamp generation when parser is in use.

Originally committed as revision 8725 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 11 insertions, 0 deletions

diff --git a/libavformat/utils.c b/libavformat/utils.c
index c82d7dac84..b748b546ca 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -584,6 +584,7 @@ static void compute_pkt_fields(AVFormatContext *s, AVStream *st,
                                AVCodecParserContext *pc, AVPacket *pkt)
 {
     int num, den, presentation_delayed, delay, i;
+    int64_t offset;
     /* handle wrapping */
     if(st->cur_dts != AV_NOPTS_VALUE){
         if(pkt->pts != AV_NOPTS_VALUE)
@@ -599,6 +600,16 @@ static void compute_pkt_fields(AVFormatContext *s, AVStream *st,
         }
     }
 
+    /* correct timestamps with byte offset if demuxers only have timestamps on packet boundaries */
+    if(pc && st->need_parsing == AVSTREAM_PARSE_TIMESTAMPS && pkt->size){
+        /* this will estimate bitrate based on this frame's duration and size */
+        offset = av_rescale(pc->offset, pkt->duration, pkt->size);
+        if(pkt->pts != AV_NOPTS_VALUE)
+            pkt->pts += offset;
+        if(pkt->dts != AV_NOPTS_VALUE)
+            pkt->dts += offset;
+    }
+
     if(is_intra_only(st->codec))
         pkt->flags |= PKT_FLAG_KEY;