[Live-devel] Why VLC show fixed fps when use H264VideoStreamDiscreteFramer to send H264 data?

[Ross Finlayson]

I’m not totally sure I understand your question, because “H264VideoStreamDiscreteFramer” does not compute (or use) a ‘frame rate’ at all.  The ancestor class “H264or5VideoStreamFramer” *does* contain a ‘fFrameRate” field, but that field is not computed (or used) when you’re using one of the “*DiscreteFramer" subclasses.  It is used only when you’re using one of the (non-Discrete) Framer classes directly - to parse an input video byte stream.

Therefore, when you’re feeding a “*DiscreteFramer” from a live source (e.g., from an encoder), then you should make sure that the NAL units are being fed at their natural rate (i.e., at the rate at which they would come naturally from the encoder).  You should also, of course, make sure that the encoder generates SPS and PPS NAL units that properly encode the actual video frame rate.  (That’s always important, of course; it’s not specific to LIVE555.)


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