contrib: Add libav patch for better DV in AVI compatibility.

(cherry picked from commit efbe7038856d931b79eeb904e7a5e6bad31df38c)

diff --git a/contrib/ffmpeg/A12-avi-dv.diff b/contrib/ffmpeg/A12-avi-dv.diff
new file mode 100644 (file)
index 0000000..1424fcc
--- /dev/null
+++ b/contrib/ffmpeg/A12-avi-dv.diff
@@ -0,0 +1,37 @@
+commit 0fc61c6ab6912a2f0c40fdd3f3c591bc2a33efd4
+Author: Michael Niedermayer <michaelni@gmx.at>
+Date:   Sat Nov 28 21:06:45 2015 +0100
+
+    avi: Validate the stream-id for DV as well
+    
+    Avoid false positives while syncing.
+    
+    Bug-Id: ffmpeg/4086
+    Bug-Id: 879
+    
+    Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
+    Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
+
+diff --git a/libavformat/avidec.c b/libavformat/avidec.c
+index 43c178f..477e045 100644
+--- a/libavformat/avidec.c
++++ b/libavformat/avidec.c
+@@ -995,7 +995,7 @@ start_sync:
+             goto start_sync;
+         }
+ 
+-        n = avi->dv_demux ? 0 : get_stream_idx(d);
++        n = get_stream_idx(d);
+ 
+         if (!((i - avi->last_pkt_pos) & 1) &&
+             get_stream_idx(d + 1) < s->nb_streams)
+@@ -1007,6 +1007,9 @@ start_sync:
+             goto start_sync;
+         }
+ 
++        if (avi->dv_demux && n != 0)
++            continue;
++
+         // parse ##dc/##wb
+         if (n < s->nb_streams) {
+             AVStream *st;