Wowza Community

Moving with large VOD archive from FMS to Wowza -> audio-sync problem

Hi,

at the moment we are using wowza for live streaming to iOS and transcoding and it’s working really nice.

The next step is replacing our external cdn provider to do the VOD rtmp with our own wowza servers, but we have one problem.

Our archive consists of 25.000 files and have a size of about 6 TB. Recorded from our live streams with FMS as .f4v.

Most of this files have an audio delay if they are played over wowza. I know that FMS recording is not watiing for the first keyframe and so many of our .f4v files are not starting with a keyframe and this seems the reason why we have an audio delay with wowza. Audio starts immediately, video is starting when the first keyframe occurs. I’ve tested some of our files with different flash players, different CDNs, different FMS versions and different desktop players, but just with wowza there is an audio delay.

If a cut the first second with ffmpeg like

ffmpeg -ss 1 -i orig.f4v -vcodec copy -acodec copy out.mp4

the newly created file is working without delay with wozwa. But unfortunately this is not an option for our 25.000 files, because the remuxing/cutting would take too long, we had to check every single file is working after remuxing/cutting (sometimes ffmpeg just do strange things), for every single file there a timing xml files which have to be updated…

So I hope there is an option to tell wowza starting audio with the first keyframe like FMS and all other players are doing.

Can someone give me a hint or have a solution? Is it possible to get this working with a custom wowza module?

[EDIT]here a link to a testfile http://ge.tt/3Kh0VAH [/EDIT]

Thanks!

JT