[Live-devel] [PATCH]MPEG1-Audio for Kasenna

[Ross Finlayson]

Grumble......

First, regarding the patch to "RTSPClient.cpp", please change it so 
that you are not simply duplicating the assignment to "sdpFmt" in the 
two branches.  Since the only change between the two branches is 
"video" vs "audio" in the "m=" line, you should be able to change 
this so that it continues to assign "sdpFmt" only once.

Second, there is (to my knowledge) nothing wrong with 
"StreamParser".  Note that it is - as its name implies - meant for 
parsing a *byte stream* source (from which you can read 
arbitrarily-sized chunks of data).  The problem is that you are not 
feeding it a byte stream source.  Instead, you are trying to feed it 
a "BasicUDPSource", which "StreamParser" was not designed to read from.

Since your input (raw-UDP) packets contain MPEG audio frames as is, 
then I don't see why you need any 'framer' object in front of the 
"BasicUDPSource".  Instead, just deliver the data, as is, to 
VLC.  What's that you say?  VLC needs a presentation time?  Gee, if 
only there were some standard streaming media protocol that includes 
a presentation timestamp - then Kasenna could have used that!  Excuse 
my sarcasm, but I hope you can see why I have such disdain for 
Kasenna (a company which, by the way, I am in the process of putting 
out of business).

If VLC can't handle playing MPEG audio data without a presentation 
timestamp (but it should be able to, because it's able to play HTTP 
MPEG audio streams just fine!), then I suggest writing a new 
"MPEG1or2AudioStreamDiscreteFramer" (a subclass of "FramedFilter") 
that - unlike "MPEG1or2AudioStreamFramer" - assumes that its input 
data will be (integral multiples of) discrete MPEG audio 
frames.  (Don't tell me that Kasenna delivers its MPEG audio data so 
that UDP packet boundaries don't align with MPEG audio frame 
boundaries - then I'll really puke :-)


	Ross Finlayson
	Live Networks, Inc. (LIVE555.COM)
	<http://www.live555.com/>