[FFmpeg-devel] [PATCH] lavf/mov.c: Use the first sidx for tracks without sidx.

[Sasi Inguva]

According to spec ISO_IEC_15444_12 "For any media stream for which no segment index is present, referred to as non‐indexed stream, the media stream associated with the first Segment Index box in the segment serves as a reference stream in a sense that it also describes the subsegments for any non‐indexed media stream."

Signed-off-by: Sasi Inguva <isasi at google.com>
---
 libavformat/isom.h |  1 +
 libavformat/mov.c  | 25 ++++++++++++++++++++++---
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/libavformat/isom.h b/libavformat/isom.h
index 9038057..d684502 100644
--- a/libavformat/isom.h
+++ b/libavformat/isom.h
@@ -179,6 +179,7 @@ typedef struct MOVStreamContext {
     int32_t *display_matrix;
     uint32_t format;
 
+    int has_sidx;  // If there is an sidx entry for this stream.
     struct {
         int use_subsamples;
         uint8_t* auxiliary_info;
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 357d800..d9ed5a3 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -4202,7 +4202,8 @@ static int mov_read_sidx(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     uint8_t version;
     unsigned i, track_id;
     AVStream *st = NULL;
-    MOVStreamContext *sc;
+    AVStream *ref_st;
+    MOVStreamContext *sc, *ref_sc;
     MOVFragmentIndex *index = NULL;
     MOVFragmentIndex **tmp;
     AVRational timescale;
@@ -4284,9 +4285,26 @@ static int mov_read_sidx(MOVContext *c, AVIOContext *pb, MOVAtom atom)
 
     c->fragment_index_data = tmp;
     c->fragment_index_data[c->fragment_index_count++] = index;
+    sc->has_sidx = 1;
+
+    if (offset == avio_size(pb)) {
+        for (i = 0; i < c->fc->nb_streams; i++) {
+            if (c->fc->streams[i]->id == c->fragment_index_data[0]->track_id) {
+                ref_st = c->fc->streams[i];
+                ref_sc = ref_st->priv_data;
+                break;
+            }
+        }
+        for (i = 0; i < c->fc->nb_streams; i++) {
+            st = c->fc->streams[i];
+            sc = st->priv_data;
+            if (!sc->has_sidx) {
+                st->duration = sc->track_end = av_rescale(ref_st->duration, sc->time_scale, ref_sc->time_scale);
+            }
+        }
 
-    if (offset == avio_size(pb))
         c->fragment_index_complete = 1;
+    }
 
     return 0;
 }
@@ -5846,13 +5864,14 @@ static int mov_read_packet(AVFormatContext *s, AVPacket *pkt)
 static int mov_seek_fragment(AVFormatContext *s, AVStream *st, int64_t timestamp)
 {
     MOVContext *mov = s->priv_data;
+    MOVStreamContext *sc = st->priv_data;
     int i, j;
 
     if (!mov->fragment_index_complete)
         return 0;
 
     for (i = 0; i < mov->fragment_index_count; i++) {
-        if (mov->fragment_index_data[i]->track_id == st->id) {
+        if (mov->fragment_index_data[i]->track_id == st->id || !sc->has_sidx) {
             MOVFragmentIndex *index = mov->fragment_index_data[i];
             for (j = index->item_count - 1; j >= 0; j--) {
                 if (index->items[j].time <= timestamp) {
-- 
2.8.0.rc3.226.g39d4020