[Live-devel] crapy sound when streaming from pipes

[Ross Finlayson]

>I am trying to stream MPEG2 audio with modified 
>testMPEG1or2AudioVideoStreamer.
>It works good with plain files, but when I try to stream from pipe (with 
>mpeg2ts demuxer on the other side) it produced the following effect: for 
>two or three seconds all is fine, then sound stops for quater or whole 
>second and so on.

I suspect that the problem here is that the "ByteStreamFileSource" class - 
which reads data from the input file (in your case, a pipe) - does 
synchronous (blocking) reads.  While this code is blocked reading on the 
input file (or pipe), no other LIVE.COM library code runs.  This is not 
usually a problem when streaming from a file, but may be a problem when 
streaming from a pipe.

You can overcome this, I think, in one of two ways:
1/ Have the class that reads from your pipe do asynchronous reads (using 
"TaskScheduler::turnOnBackgroundReadHandling()").  (You can use 
"liveMedia/DeviceSource.cpp" as a model for this.)

2/ Feed the output from your MPEG-2 Transport Stream demuxer directly into 
the LIVE.COM data chain, thereby avoiding the need for a pipe (and a 
"ByteStreamFileSource") at all.  If you do this, though, your MPEG-2 
Transport Stream demuxer will need to be rewritten using the event-driven 
style of other LIVE.COM filters.


	Ross Finlayson
	LIVE.COM
	<http://www.live.com/>