[Live-devel] green screen at the start of MPEG4 stream reception

[Ross Finlayson]

>While receiving and playing back MPEG4 encoded streams using VLC, 
>the first few frames happen to be green screen. The message window 
>shows the following error
>"ffmpeg warning: warning: first frame is no keyframe". The playback 
>gets back to normal state on the arrival on next MPEG4 keyframe. I 
>observed this with testMPEG4VideoStreamer.exe. and the issue is 
>consistent with repeated runs.
>Is it because client didn't get first few frames on MPEG4 stream?

Yes, probably.

>  where do the frames gets dropped?

Remember that "testMPEG4VideoStreamer" is a *multicast* application - 
it just sends the data to a multicast group, regardless of how many 
clients have subscribed to the group.  Therefore, any data that it 
sends before the client runs (and subscribes to the group) will be 
lost.

To avoid this, use unicast streaming, using "testOnDemandRTSPServer", 
or "live555MediaServer".
-- 

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