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CalculateChunkIDBasedOnTimecode not always working

Hi there

The setting (CalculateChunkIDBasedOnTimecode) is perfectly working when using FMLE. Although, i did not find any other (software) encoder yet, which are working as well. Do you have any recommendation, or explanation why this feature seems to be working only with FMLE?

Chris

Hello Chris,

While I can’t make a recommendation on on encoders the following may help to explain how this option functions in relation to encoder settings:

Some things that we have noticed with this system for calculating chunk ids is that you have to be careful that you set the packetizer chunk target duration and encoder key frame interval correctly so that they will work together. The chunks are created on key frame intervals and the system uses the keyframe timecodes and chunk duration target in a calculation to work out the chunk id and when to generate a new chunk. To make sure that it works properly, you need to make sure that the key frame interval divides evenly into the chunk duration target. i.e. for a 2 second key frame interval (2000 ms) you would use a chunk duration target of 10000 (which is the default anyway). If you are finding that you are getting inconsistent chunk ids then use the debug properties listed below to make sure the key frame intervals and chunk duration target are what you expect and that obviously they are the same settings across each server that is running the stream.

You can set the chunk duration target by using the following property in the LiveStreamPacketizer / Properties.

cupertinoChunkDurationTarget It is a millisecond value and the default is 10000.

For more info on this and other related settings, please refer to the following article.

https://www.wowza.com/docs/how-to-configure-apple-hls-packetization-cupertinostreaming

I hope this helps.

Regards,

Jason Hatchett