Wowza Community

HLS Problem

Hi,

I just recently switched from HDS to HLS, but since then my movie not playing well!

I mean while you’re watching movie unreasonably it moves forward or backward when bit-rate switching happening.

For example, I’m watching movie in 00:00:10, then player decide to play better quality. When bit-rate switching happening, movie goes forward without any reason and start playing the new bit-rate on 00:00:20. Or sometimes it goes back and play from 00:00:05!

Can you please help me with this.

Thanks a lot.

Hi,

What you are describing sounds very much like a key-frame alignment problem between the live streams or vod files (depending whether this is live or vod streaming).

This is how to troubleshoot keyframe alignment for live streaming:

If you want to troubleshoot vod alignment, you’ll need to go through these steps first, make multi bitrate vod streams live while running the debug.

Daren

You need a file encoder that will encode renditions of your stream that are key frame aligned. We have documentation for Expression 4 Encoder here. Note that you need a Expression 4 suite (web or ultimate) to enable the h.264 encoding feature of Expression 4 Encoder.

Richard

Hi,

Yes, you will need to make sure that the VOD files are properly key-frame aligned during the encoding process.

You can take a look at this forum post for an example on how to use FFMPEG to generate properly key-frame aligned VOD files:

Zoran

Thanks for your reply.

So, how can I perform the key-frame alignment in each VoD stream?

Is it some kind of configuration on the streaming side? Or I have to do the key-frame alignment when I’m encoding things?

Thanks a lot.