[Live-devel] Stream h264 - bitrate's effect on latency

[Ross Finlayson]

> I have three Raspi cameras pushing out h264 elementary streams, which I'm reading from stdin and sending out using live555's RTSP server. All works great.
> 
> The only problem is that the three camera feeds can sometimes have different bitrates depending on what they're looking at - I want them syncronized. It seems that the cameras with the higher bitrates are closer to real-time, and the lower bitrates lag more. I expect this is because there is some fixed-size buffer somewhere, and the higher the bitrate, the faster the buffer is filled and the more realtime the stream is.

This buffer will be the buffer that's in your OS - between your camera (that's writing to 'stdout'), and the LIVE555 server (that's reading from 'stdin').  I.e., it'll be in whatever pipe you have between the camera and the server.

It may be possible (using some ioctl() or something) to change this buffer size.  Alternatively, you may find it easier to have your camera's encoder use a (virtual) file that's named in the file system (e.g., somewhere in /dev), and then have the LIVE555 server read directly from this 'file', rather than from stdin.  That will avoid having an intermediate pipe set up by the OS.

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

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.live555.com/pipermail/live-devel/attachments/20140427/bc61f950/attachment.html>