patch ffmpeg avi seek problem

when seeking to a timestamp, ffmpeg seeks to the position in the primary
stream where that timestamp starts. Then seeks to the next interleaved packet 
for all other streams. When seeking back to the beginning of the file, this
means the first packet of some streams are missed if those streams start 
before the video stream in the file.


git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@3296 b64f7644-9d1e-0410-96f1-a4d463321fa5

1 files changed, 45 insertions, 0 deletions

diff --git a/contrib/ffmpeg/A05-avi-seek.patch b/contrib/ffmpeg/A05-avi-seek.patch
new file mode 100644
index 000000000..a1dec93ca
--- /dev/null
+++ b/contrib/ffmpeg/A05-avi-seek.patch
@@ -0,0 +1,45 @@
+Index: libavformat/avidec.c
+===================================================================
+--- ffmpeg.orig/libavformat/avidec.c	(revision 22950)
++++ ffmpeg/libavformat/avidec.c	(working copy)
+@@ -1072,7 +1072,7 @@
+     AVIContext *avi = s->priv_data;
+     AVStream *st;
+     int i, index;
+-    int64_t pos;
++    int64_t pos, min_pos;
+     AVIStream *ast;
+ 
+     if (!avi->index_loaded) {
+@@ -1109,6 +1109,7 @@
+         return 0;
+     }
+ 
++    min_pos = pos;
+     for(i = 0; i < s->nb_streams; i++) {
+         AVStream *st2 = s->streams[i];
+         AVIStream *ast2 = st2->priv_data;
+@@ -1129,10 +1130,12 @@
+             index=0;
+ 
+         if(!avi->non_interleaved){
++            while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)
++                index++;
+             while(index>0 && st2->index_entries[index].pos > pos)
+                 index--;
+-            while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)
+-                index++;
++            if (st2->index_entries[index].pos < min_pos)
++                min_pos = st2->index_entries[index].pos;
+         }
+ 
+ //        av_log(s, AV_LOG_DEBUG, "%"PRId64" %d %"PRId64"\n", timestamp, index, st2->index_entries[index].timestamp);
+@@ -1141,7 +1144,7 @@
+     }
+ 
+     /* do the seek */
+-    url_fseek(s->pb, pos, SEEK_SET);
++    url_fseek(s->pb, min_pos, SEEK_SET);
+     avi->stream_index= -1;
+     return 0;
+ }