Hi everyone,

I've been banging my head against every wall in my house for weeks now with this problem.

If you try to add metadata using insert_metadata, add_timeout and execute to an input.jack(), it will end up failing (audio doesn't get through anymore, only metadata (!)). When this happens, input.jack() discards everything it gets from Jack.

Now, one "solution" that has been proposed by David was to augment the size of the frames. 4096 instead of 1024 seems to stabilize the stuff.

But it has introduced a "new" problem: everytime metadata gets updated, some samples go missing, which creates a strange effect when you're listening to the stream.

This "new" problem isn't exactly new: I recall very well having encountered it when inserting metadata on Pytagor's stream (which is based on input.alsa). Now, the thing I don't really remember is whether or not we solved this problem -- I think yes -- and above all, how.

Last but not least, I have noticed on two streams generated by Liquidsoap that use metadata insertion that oggz-validate reports inconsistencies in the packet ordering:

$ oggz-validate --partial /tmp/dfs.ogg
/tmp/dfs.ogg: Error:
00:00:00.000: serialno 1167312499: Packet out of order (previous 00:00:30.377) 00:00:00.000: serialno 0056579649: Packet out of order (previous 00:00:29.609) 00:00:00.000: serialno 2012438971: Packet out of order (previous 00:00:30.291) 00:00:00.000: serialno 0283177365: Packet out of order (previous 00:00:29.694) 00:00:00.000: serialno 1720377089: Packet out of order (previous 00:00:30.291)
etc.

This is true on this test stream which uses input.jack (running latest SVN), but this is also true on Pytagor's stream, which is running rev 3703, and uses input.alsa. The metadata insertion methods are identical: insert_metadata + add_timeout + execute.

This is however not true on another test stream which is created by Ices, but has no metadata update. I will be investigating soon to see if I can find an Ogg Vorbis stream that has metadata updates but that wasn't generated by Liquidsoap.

--

Regards,
Vincent Tabard
Radio Pytagor : http://www.radiopytagor.com/


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