+From eeb38d760d0748b14c4faed1bfd04efad9ed0806 Mon Sep 17 00:00:00 2001
+From: John Stebbins <stebbins@jetheaddev.com>
+Date: Sun, 19 Feb 2017 14:45:44 -0700
+Subject: [PATCH] mov: fix edit list issue that can cause A/V desync
+
+Only the first entry in the edit list was factored into the time_offset
+of the first sample in a track. But when there is a delay (empty edit
+entry) the mediatime from the second entry must also be factored into
+the time_offset.
+---
+ libavformat/isom.h | 2 ++
+ libavformat/mov.c | 30 ++++++++++++++++++++++--------
+ 2 files changed, 24 insertions(+), 8 deletions(-)
+
diff --git a/libavformat/isom.h b/libavformat/isom.h
-index 8cc5ab7..0050d3a 100644
+index 8cc5ab7..7c345e9 100644
--- a/libavformat/isom.h
+++ b/libavformat/isom.h
@@ -125,6 +125,8 @@ typedef struct MOVStreamContext {
int *keyframes;
int time_scale;
int64_t time_offset; ///< time offset of the first edit list entry
-+ int64_t delay; ///< time delay of the first edit list entry
-+ int64_t skip; ///< time to skip of the first or second edit list entry
++ int64_t time_offset_delay;
++ int64_t time_offset_skip;
int current_sample;
unsigned int bytes_per_frame;
unsigned int samples_per_frame;
diff --git a/libavformat/mov.c b/libavformat/mov.c
-index 5c9f85c..c749b46 100644
+index 5c9f85c..1657647 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
-@@ -2323,9 +2323,9 @@ static void mov_build_index(MOVContext *mov, AVStream *st)
+@@ -2323,10 +2323,10 @@ static void mov_build_index(MOVContext *mov, AVStream *st)
uint64_t stream_size = 0;
/* adjust first dts according to edit list */
- if (sc->time_offset && mov->time_scale > 0) {
- if (sc->time_offset < 0)
- sc->time_offset = av_rescale(sc->time_offset, sc->time_scale, mov->time_scale);
+- current_dts = -sc->time_offset;
+ if (mov->time_scale > 0) {
-+ sc->time_offset = sc->skip -
-+ av_rescale(sc->delay, sc->time_scale, mov->time_scale);
- current_dts = -sc->time_offset;
++ sc->time_offset = av_rescale(sc->time_offset_delay, sc->time_scale,
++ mov->time_scale) - sc->time_offset_skip;
++ current_dts = sc->time_offset;
}
-@@ -2986,6 +2986,10 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
- unsigned entries, first_sample_flags = frag->flags;
- int flags, distance, i, err;
-
+ /* only use old uncompressed audio chunk demuxing when stts specifies it */
+@@ -2999,6 +2999,10 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+ sc = st->priv_data;
+ if (sc->pseudo_stream_id+1 != frag->stsd_id)
+ return 0;
+ if (c->time_scale > 0) {
-+ sc->time_offset = sc->skip -
-+ av_rescale(sc->delay, sc->time_scale, c->time_scale);
++ sc->time_offset = av_rescale(sc->time_offset_delay, sc->time_scale,
++ c->time_scale) - sc->time_offset_skip;
+ }
- for (i = 0; i < c->fc->nb_streams; i++) {
- if (c->fc->streams[i]->id == frag->track_id) {
- st = c->fc->streams[i];
+ avio_r8(pb); /* version */
+ flags = avio_rb24(pb);
+ entries = avio_rb32(pb);
+@@ -3029,7 +3033,7 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+ }
+ if (flags & MOV_TRUN_DATA_OFFSET) data_offset = avio_rb32(pb);
+ if (flags & MOV_TRUN_FIRST_SAMPLE_FLAGS) first_sample_flags = avio_rb32(pb);
+- dts = sc->track_end - sc->time_offset;
++ dts = sc->track_end + sc->time_offset;
+ offset = frag->base_data_offset + data_offset;
+ distance = 0;
+ av_log(c->fc, AV_LOG_TRACE, "first sample flags 0x%x\n", first_sample_flags);
+@@ -3069,7 +3073,7 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+ return AVERROR_EOF;
+
+ frag->implicit_offset = offset;
+- st->duration = sc->track_end = dts + sc->time_offset;
++ st->duration = sc->track_end = dts - sc->time_offset;
+ return 0;
+ }
+
@@ -3152,6 +3156,7 @@ static int mov_read_elst(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
MOVStreamContext *sc;
int i, edit_count, version;
-+ int found_delay = 0;
++ int time_offset_done = 0;
if (c->fc->nb_streams < 1)
return 0;
-@@ -3164,7 +3169,7 @@ static int mov_read_elst(MOVContext *c, AVIOContext *pb, MOVAtom atom)
- if ((uint64_t)edit_count*12+8 > atom.size)
- return AVERROR_INVALIDDATA;
-
-- for (i=0; i<edit_count; i++){
-+ for (i=0; i < edit_count; i++){
- int64_t time;
- int64_t duration;
- if (version == 1) {
-@@ -3175,8 +3180,15 @@ static int mov_read_elst(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+@@ -3175,8 +3180,17 @@ static int mov_read_elst(MOVContext *c, AVIOContext *pb, MOVAtom atom)
time = (int32_t)avio_rb32(pb); /* media time */
}
avio_rb32(pb); /* Media rate */
- if (i == 0 && time >= -1) {
- sc->time_offset = time != -1 ? time : -duration;
-+ if (i == 0 && time == -1) {
-+ sc->delay = duration;
-+ found_delay = 1;
-+ }
-+ else if (i == 0 && time >= 0) {
-+ sc->skip = time;
-+ }
-+ else if (i == 1 && found_delay && time >= 0) {
-+ sc->skip = time;
++ if (!time_offset_done) {
++ if (time == -1) {
++ /* delay is in movie timescale */
++ sc->time_offset_delay += duration;
++ } else if (time >= 0) {
++ /* samples to skip is in track timescale */
++ sc->time_offset_skip = time;
++ time_offset_done = 1;
++ }
++ /* timescales may not be known yet, so we can not compute
++ * a single combined time_offset yet */
}
}
+--
+2.9.3
+
projects / handbrake / commitdiff