[FFmpeg-devel] [PATCH 1/2] lavf/mov: fix parsing QuickTime meta after the first track

[Rodger Combs]

I'm not entirely sure why found_hdlr_mdta existed to begin with, so cc-ing
Tinglin Liu (who originally wrote the patch) and Derek Buitenhuis (who signed
off on it) hoping for some background. If these checks actually do have a
purpose, then the `type == MKTAG('m','d','t','a')` check should be moved
to before the `c->fc->nb_streams < 1` check instead of inside it.
---
 libavformat/isom.h |  1 -
 libavformat/mov.c  | 10 +++-------
 2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/libavformat/isom.h b/libavformat/isom.h
index 2246fed..6b6f678 100644
--- a/libavformat/isom.h
+++ b/libavformat/isom.h
@@ -198,7 +198,6 @@ typedef struct MOVContext {
     int64_t duration;     ///< duration of the longest track
     int found_moov;       ///< 'moov' atom has been found
     int found_mdat;       ///< 'mdat' atom has been found
-    int found_hdlr_mdta;  ///< 'hdlr' atom with type 'mdta' has been found
     int trak_index;       ///< Index of the current 'trak'
     char **meta_keys;
     unsigned meta_keys_count;
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 6e80b93..54530e3 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -381,7 +381,7 @@ retry:
                     av_log(c->fc, AV_LOG_ERROR, "Error parsing cover art.\n");
                 }
                 return ret;
-            } else if (!key && c->found_hdlr_mdta && c->meta_keys) {
+            } else if (!key && c->meta_keys) {
                 uint32_t index = AV_RB32(&atom.type);
                 if (index < c->meta_keys_count) {
                     key = c->meta_keys[index];
@@ -694,12 +694,8 @@ static int mov_read_hdlr(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     av_log(c->fc, AV_LOG_TRACE, "ctype= %.4s (0x%08x)\n", (char*)&ctype, ctype);
     av_log(c->fc, AV_LOG_TRACE, "stype= %.4s\n", (char*)&type);
 
-    if (c->trak_index < 0) {  // meta not inside a trak
-        if (type == MKTAG('m','d','t','a')) {
-            c->found_hdlr_mdta = 1;
-        }
+    if (c->fc->nb_streams < 1) // meta before first trak
         return 0;
-    }
 
     st = c->fc->streams[c->fc->nb_streams-1];
 
@@ -4505,7 +4501,7 @@ static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom)
 
         // Supports parsing the QuickTime Metadata Keys.
         // https://developer.apple.com/library/mac/documentation/QuickTime/QTFF/Metadata/Metadata.html
-        if (!parse && c->found_hdlr_mdta &&
+        if (!parse &&
             atom.type == MKTAG('m','e','t','a') &&
             a.type == MKTAG('k','e','y','s')) {
             parse = mov_read_keys;
-- 
2.10.0