mov: Allow more than one keyframe per trun

The previous restriction was partially designed to fix certain
(broken) samples from bug 215. There should be no restriction on the
number of keyframes per fragment or trun.

The spec suggests that all frames lacking MOV_FRAG_SAMPLE_FLAG_IS_NON_SYNC
are key frames, but we require the flag MOV_FRAG_SAMPLE_FLAG_DEPENDS_YES
to be unset as well. This works for (possibly broken) media that never
sets the NON_SYNC flag and should also be correct for any spec-compliant
file.

For files that never set either of the flags, all samples are marked
as keyframes.

Signed-off-by: Martin Storsjö <martin@martin.st>

diff --git a/libavformat/mov.c b/libavformat/mov.c
index 8bf1b90c978c66c53b6edaf2d43a591fd85f4bd6..bb99f759c7faae73353d3a775c94609ea1b82584 100644 (file)
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -2836,7 +2836,7 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     int64_t dts;
     int data_offset = 0;
     unsigned entries, first_sample_flags = frag->flags;
-    int flags, distance, i, found_keyframe = 0, err;
+    int flags, distance, i, err;
 
     for (i = 0; i < c->fc->nb_streams; i++) {
         if (c->fc->streams[i]->id == frag->track_id) {
@@ -2900,8 +2900,8 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
         sc->ctts_count++;
         if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
             keyframe = 1;
-        else if (!found_keyframe)
-            keyframe = found_keyframe =
+        else
+            keyframe =
                 !(sample_flags & (MOV_FRAG_SAMPLE_FLAG_IS_NON_SYNC |
                                   MOV_FRAG_SAMPLE_FLAG_DEPENDS_YES));
         if (keyframe)