Why is the m3u8 product video duration longer than the mp4 version?

Technical Q&A
1

I’ve just upgraded a theme for a client and encountered found that the m3u8 that’s generated for a product video has a different duration than the mp4 version, where it’s much longer and most of it is just the last frame.

m3u8 (10 mins +)
m3u8 (10 mins +)1556×1496 115 KB

The m3u8 which Safari seems to show by default, with 10:22:44 duration, where everything after 4 secs is the final frame.

mp4 (4 seconds)
mp4 (4 seconds)1492×1478 105 KB

Correct 4 second duration, which I’m looping (video is just the shoe revolving).

Has anyone else encountered this?

2

It sounds like the issue may be with the video encoding.

3

It appears to have been due to the frame rate the client was using, as the original timeline was created using still images, they used 2fps to create the effect. However this causes a miscalculation in the duration with the m3u8 streaming method.

Changed the frame rate to 30fps and problem solved.