How to adjust the frame playback speed when muxing H264 to MP4

[pinkfloyda]

Currently I am developing a media streaming app in Android (<=4.2), I need to use mp4parser at the final step to convert raw H264 file to MP4 file. Currently the issue is the final mp4 video plays too fast! And I searched around, it seems like H264 does not have timing info for each frame, it is the Muxer's responsibility. Does MP4Parser can do the timing for each frame?

Currently, I control the playback speed by providing timeScale and frameTick parameters to H264TrackImpl, I found that tune timeScale / frameTick = 10 seems normal speed. But it is really hard to keep sync with AAC audios recorded separately. Does MP4Parser support adjust the Video frames along with the Audio Track?

[flieks]

Is this the only way to control speed ? i see in BasicContainer there is also timeScale Box but didn't find the frameTick yet

[sannies]

It's in the Decoding Time to Sample box - typically at /moov/trak/mdia/minf/stbl/stts

2015-11-30 16:17 GMT+01:00 De Lille Felix [email protected]:

Is this the only way to control speed ? i see in BasicContainer there is also timeScale Box but didn't find the frameTick yet

— Reply to this email directly or view it on GitHub https://github.com/sannies/mp4parser/issues/111#issuecomment-160658088.

[flieks]

hi @sannies thanks but where does /moov/trak/mdia/minf/stbl/stts point to ? a file on github here ? or in the boxes? i only found:

• sampleDescriptionBox
• timeToSampleBox
• syncSampleBox
• SampleToChunkBox
• SampleSizeBox
• StaticChunkOffsetBox

in the boxes in BasicContainer

ah ok i understand i'm navigating to it now

[flieks]

see this @sannies https://github.com/sannies/mp4parser/issues/144

[designerMichael]

hi, have anyone fixed the synchronization problem?