[Live-devel] FPS limit

[Ross Finlayson]

>I'm working on an Application using live555 to obtain images from 
>different cameras using rtsp. I readed about the FPS or bandwith 
>maximum on the FAQ and I only readed the question about the packet 
>loss. My problem not is the packet loss, I'm suffering buffering. 
>When I have a lot of cameras, for example 12 cameras 320x240 25 FPS 
>I can see buffering of 5-6 seconds in some cases.
>
>My code decompress all the images on different threads and the CPU 
>have their usage at 65% more or less. I can say that my decompress 
>process don't have the buffering, I debugged all a lot of time and I 
>see the image queue empty. Then my question is. Exist any limitation 
>of FPS or Bandwidth on live555? or bottle neck?

Probably not.  At the server (sender) end, there is no significant 
delay in the LIVE555 code; it transmits each packet as soon as it is 
full.  At the receiver end, there should also be no significant 
delay, provided that your code returns to the event loop (i.e., calls 
"select()") regularly, without excessive delay.  Because your image 
decompression is done by separate threads - i.e., outside the LIVE555 
event loop - there should not be a problem.  If there is any 
'buffering' happening, then it will either be inside the receiver's 
OS (socket buffering), or (much more likely) somewhere else outside 
the LIVE555 code.

In any case, it should be fairly easy, I think, for you to instrument 
your application to figure out exactly where the delay is occurring 
(i.e., by generating and logging timestamps at various points in the 
code).
-- 

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