[vlc-commits] demux: mp4: set samples duration

[Francois Cartegnie]

vlc | branch: master | Francois Cartegnie <fcvlcdev at free.fr> | Thu Jan  4 19:40:31 2018 +0100| [096500ddebd4d621ea8ce96cdd93baa2ce05a2a8] | committer: Francois Cartegnie

demux: mp4: set samples duration

> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=096500ddebd4d621ea8ce96cdd93baa2ce05a2a8
---

 modules/demux/mp4/mp4.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/modules/demux/mp4/mp4.c b/modules/demux/mp4/mp4.c
index 5be7031a1f..ee984fb764 100644
--- a/modules/demux/mp4/mp4.c
+++ b/modules/demux/mp4/mp4.c
@@ -369,6 +369,53 @@ static inline bool MP4_TrackGetPTSDelta( demux_t *p_demux, mp4_track_t *p_track,
     return false;
 }
 
+static inline mtime_t MP4_GetSamplesDuration( demux_t *p_demux, mp4_track_t *p_track,
+                                              unsigned i_nb_samples )
+{
+    VLC_UNUSED( p_demux );
+
+    const mp4_chunk_t *p_chunk = &p_track->chunk[p_track->i_chunk];
+    stime_t i_duration = 0;
+
+    /* Forward to right index, and set remaining count in that index */
+    unsigned i_index = 0;
+    unsigned i_remain = 0;
+    for( unsigned i = p_chunk->i_sample_first;
+         i<p_track->i_sample && i_index < p_chunk->i_entries_dts; )
+    {
+        if( p_track->i_sample - i >= p_chunk->p_sample_count_dts[i_index] )
+        {
+            i += p_chunk->p_sample_count_dts[i_index];
+            i_index++;
+        }
+        else
+        {
+            i_remain = p_track->i_sample - i;
+            break;
+        }
+    }
+
+    /* Compute total duration from all samples from index */
+    while( i_nb_samples > 0 && i_index < p_chunk->i_entries_dts )
+    {
+        if( i_nb_samples >= p_chunk->p_sample_count_dts[i_index] - i_remain )
+        {
+            i_duration += (p_chunk->p_sample_count_dts[i_index] - i_remain) *
+                          (int64_t) p_chunk->p_sample_delta_dts[i_index];
+            i_nb_samples -= (p_chunk->p_sample_count_dts[i_index] - i_remain);
+            i_index++;
+            i_remain = 0;
+        }
+        else
+        {
+            i_duration += i_nb_samples * p_chunk->p_sample_delta_dts[i_index];
+            break;
+        }
+    }
+
+    return MP4_rescale( i_duration, p_track->i_timescale, CLOCK_FREQ );
+}
+
 static inline int64_t MP4_GetMoviePTS(demux_sys_t *p_sys )
 {
     return p_sys->i_nztime;
@@ -1237,6 +1284,8 @@ static int DemuxTrack( demux_t *p_demux, mp4_track_t *tk, uint64_t i_readpos,
             else
                 p_block->i_pts = VLC_TS_INVALID;
 
+            p_block->i_length = MP4_GetSamplesDuration( p_demux, tk, i_nb_samples );
+
             MP4_Block_Send( p_demux, tk, p_block );
         }