[FFmpeg-devel] libavformat/mov: Fix inserting frames before current_frame

Message ID CAO7y9i-A6qZAr_S2NRPvuomM=AM7oLm+qsBGJ0GuMh20G8CqAw@mail.gmail.com
State New
Headers

Commit Message

Jacob Trimble July 26, 2017, 10:37 p.m. UTC
When using streaming input, it may be possible to see frames that appear
before the current_frame.  When these frames are inserted into the
index, the current_frame needs to be updated so it is still pointing
at the same frame.

Signed-off-by: Jacob Trimble <modmaker@google.com>
---
 libavformat/mov.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

         if (c->fc->streams[i]->id == frag->track_id) {
@@ -4352,13 +4352,19 @@ static int mov_read_trun(MOVContext *c, AVIOContext
*pb, MOVAtom atom)
                                   MOV_FRAG_SAMPLE_FLAG_DEPENDS_YES));
         if (keyframe)
             distance = 0;
+        old_nb_index_entries = st->nb_index_entries;
         err = av_add_index_entry(st, offset, dts, sample_size, distance,
                                  keyframe ? AVINDEX_KEYFRAME : 0);
         if (err < 0) {
             av_log(c->fc, AV_LOG_ERROR, "Failed to add index entry\n");
+        } else if (err <= sc->current_sample && err + 1 !=
st->nb_index_entries &&
+            st->nb_index_entries != old_nb_index_entries) {
+            // if we inserted a new item before the current sample, move
the
+            // counter ahead so it is still pointing to the same sample.
+            sc->current_sample++;
         }
-        av_log(c->fc, AV_LOG_TRACE, "AVIndex stream %d, sample %u, offset
%"PRIx64", dts %"PRId64", "
-                "size %u, distance %d, keyframe %d\n", st->index,
sc->sample_count+i,
+        av_log(c->fc, AV_LOG_TRACE, "AVIndex stream %d, sample %d, offset
%"PRIx64", dts %"PRId64", "
+                "size %u, distance %d, keyframe %d\n", st->index, err,
                 offset, dts, sample_size, distance, keyframe);
         distance++;
         dts += sample_duration;
  

Comments

Moritz Barsnick July 27, 2017, 12:28 p.m. UTC | #1
On Wed, Jul 26, 2017 at 15:37:16 -0700, Jacob Trimble wrote:
>              av_log(c->fc, AV_LOG_ERROR, "Failed to add index entry\n");
> +        } else if (err <= sc->current_sample && err + 1 !=
> st->nb_index_entries &&
> +            st->nb_index_entries != old_nb_index_entries) {

Your mailer inserted line breaks into the patch. Please either attach
it, or even better, send it with git send-email.

Thanks,
Moritz
  

Patch

diff --git a/libavformat/mov.c b/libavformat/mov.c
index 63f84be782..d039f27063 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -4259,7 +4259,7 @@  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, err;
+    int flags, distance, i, err, old_nb_index_entries;

     for (i = 0; i < c->fc->nb_streams; i++) {