> Both File as File and File as Pipe look great on VLC over the lan.  But to 
> the iPad, the File as File looks great but the File as Pipe is very blocky, 
> as if compression info is missing or whatever.
> 
> This tells me two things:  (#1) it seems VLC may be more robust and forgiving 
> than our iPad app, as expected; and (#2) there's some difference in what 
> Live555 sends (perhaps presentation time?) depending on whether the stream 
> came from File as File or File as Pipe.

No, the difference is not the frames' presentation times, because they are 
derived from the input H.264 data, which should be the same in both cases.

The difference is likely that reads from the pipe - and thus transmissions over 
the network - are not happening smoothly.  I.e., you are probably reading a 
large chunk of data from the pipe, then waiting a long time (for more data to 
become available in the pipe), then reading a large chunk of data from the 
pipe, etc.  Because of these 'bursty' reads from the pipe, network transmission 
(of RTP packets) is also happening in a 'bursty' fashion.

Your receiving application *should* be able to handle this OK, if it does 
reasonable buffering of incoming data (i.e., data that has just been read from 
the "RTPSource" object).  But the fact that it's not handling this OK (but VLC 
does) suggests that your receiving player (on the iPad) is not buffering 
incoming data enough before decoding/rendering it.  That is the first thing 
that you should fix (because bursty/jittery data can happen in many 
environments).

However, you should also fix whatever is causing reads from your pipe (i.e., on 
your server) to be so bursty.  Because I don't know anything about your server 
OS, I can't help you here.  But if you are running Windows (which often has a 
notoriously coarse process-switching granularity), then please stop.  In this 
day and age, Windows is simply not a serious OS for running server applications.

Ross Finlayson
Live Networks, Inc.
http://www.live555.com/

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