improved 'edts' atom writing support

The 'edts' write function can now generate an initial empty edit resulting in a track-specific presentation delay.
This is automatically calculated and inserted for any track where the initial DTS != 0.
Added support for long (version==1) timecodes.
This commit is contained in:
Gil Pedersen 2011-05-02 19:25:28 +02:00 committed by Alex Converse
parent 6f1ec38ce2
commit c16919487e
1 changed files with 39 additions and 10 deletions

View File

@ -1279,20 +1279,49 @@ static int mov_write_tapt_tag(AVIOContext *pb, MOVTrack *track)
// This box seems important for the psp playback ... without it the movie seems to hang
static int mov_write_edts_tag(AVIOContext *pb, MOVTrack *track)
{
avio_wb32(pb, 0x24); /* size */
int64_t duration = av_rescale_rnd(track->trackDuration, MOV_TIMESCALE,
track->timescale, AV_ROUND_UP);
int version = duration < INT32_MAX ? 0 : 1;
int entry_size, entry_count, size;
int64_t delay, start_ct = track->cluster[0].cts;
delay = av_rescale_rnd(track->cluster[0].dts + start_ct, MOV_TIMESCALE,
track->timescale, AV_ROUND_DOWN);
version |= delay < INT32_MAX ? 0 : 1;
entry_size = (version == 1) ? 20 : 12;
entry_count = 1 + (delay > 0);
size = 24 + entry_count * entry_size;
/* write the atom data */
avio_wb32(pb, size);
ffio_wfourcc(pb, "edts");
avio_wb32(pb, 0x1c); /* size */
avio_wb32(pb, size - 8);
ffio_wfourcc(pb, "elst");
avio_wb32(pb, 0x0);
avio_wb32(pb, 0x1);
avio_w8(pb, version);
avio_wb24(pb, 0); /* flags */
/* duration ... doesn't seem to effect psp */
avio_wb32(pb, av_rescale_rnd(track->trackDuration, MOV_TIMESCALE,
track->timescale, AV_ROUND_UP));
avio_wb32(pb, entry_count);
if (delay > 0) { /* add an empty edit to delay presentation */
if (version == 1) {
avio_wb64(pb, delay);
avio_wb64(pb, -1);
} else {
avio_wb32(pb, delay);
avio_wb32(pb, -1);
}
avio_wb32(pb, 0x00010000);
}
avio_wb32(pb, track->cluster[0].cts); /* first pts is cts since dts is 0 */
/* duration */
if (version == 1) {
avio_wb64(pb, duration);
avio_wb64(pb, start_ct);
} else {
avio_wb32(pb, duration);
avio_wb32(pb, start_ct);
}
avio_wb32(pb, 0x00010000);
return 0x24;
return size;
}
static int mov_write_tref_tag(AVIOContext *pb, MOVTrack *track)
@ -1349,7 +1378,7 @@ static int mov_write_trak_tag(AVIOContext *pb, MOVTrack *track, AVStream *st)
avio_wb32(pb, 0); /* size */
ffio_wfourcc(pb, "trak");
mov_write_tkhd_tag(pb, track, st);
if (track->mode == MODE_PSP || track->flags & MOV_TRACK_CTTS)
if (track->mode == MODE_PSP || track->flags & MOV_TRACK_CTTS || track->cluster[0].dts)
mov_write_edts_tag(pb, track); // PSP Movies require edts box
if (track->tref_tag)
mov_write_tref_tag(pb, track);