livepkgr m3u8 and f4m out of sync

[CarphuntinGod]

I'm messing with my test installed ams server.

I've noticed that when I play my test audio-only live stream via the videoplayer.html file, calling it as f4m,   and also call the stream on an ipad via the m3u8 address, the two are very out of sync.

Is the sync issue coming from disparate buffering between the two devices? Difference in  encoding times on the server itself? or other?

I'm asking because if we run our radio station feeds out via this, I sort of need to have them close to in sync.

[Guest]

Hi,

HLS stream in general will have a delay of about 24 seconds, while it is lesser for an HDS stream depending upon the fragment and segment durations. Hence the sync issues between the two.

Thanks,

Apurva

[CarphuntinGod]

is there a way to lessen this in any way?

I'm  mainly concerned about some audio streams I want to run.   Not sure yet if they will be single or multi bit rate, but I'd like to attempt to do what I can to keep the streams with as little delay from the source signal as possible.

Maybe buffering settings, etc. in the conf files or anything like that able to help?

[SE_0208]

If i am not wrong you are more concerned about delay for HDS as well as HLS streams and not about keeping HDS and HLS both in sync. Anyways you can try to keep both settings same, like keeping fragment duration and hls media duration of same value , by default fragment duration is 4 and hls media duration is 8. You can make them both as 4 though Apple recommends to have it as 10. This is from server end. From client end , I am not sure whether OSMF has strict restiction like IOS client of having minium 3 fragment entries in playlist. But in iOS client you would have delay of around 12 seconds or more because that's how iOS client behaves.

[Michael_Kennedy__12345_]

You can set the OSMF pureLiveOffset parameter in your player to delay the HDS stream.

I'm not sure there is any real value in attempting to get all output formats to be in sync. The broadcast world does not keep their outputs in sync, and unless you have a special audience they probally don't know that there is a delay already. Watch the satellite feed of a game the next time you are at a stadium to see what I mean. Do you currently keep your FM/DAB broadcasts in sync?

[SE_0208]

Do agree with Micheal on his second point.

[CarphuntinGod]

Thanks everyone for the info.   That's the sort of stuff I need to know to proceed.  

Our radio station does some event stuff that people will listen to online.  The radio station will tell them that the inet stream is not "live" per se... but in the past, with the FMS 3.5 server... it wasn't very far out of time.  I'm just trying to keep the new streams we will put up as close to in time as possible.