Codec Key Frame Interval

[Luke Mauldin]

All,

Can someone please help me understand how to change a codec specific option, such as the "keyFrameInterval" for the VP8 codec?  I have tried adding this line to the end of the sessionDescrption.sdp so that the call to setLocalDescription has this line appended on the end:

a=fmtp:100 keyFrameInterval=100

Additionally, I am sending that value to the other peer, however it looks like key frames are still being generated at the default of every 3000 frames.  Can anyone help me out?

Luke

[Vikas]

Hi,

I don't think the parameter keyFrameInterval is recognized through sdp in chrome, it just gets ignored during parsing. Is this a standard parameter?

/Vikas

[Luke Mauldin]

It is not a standard parameter like framerate or size but I did notice some code that parses the parameter in the webrtc library, but I don't know if the information from the SDP actually gets passed that far into the library code.  Has anyone been able to change the key frame rate on the VP8 codec?

Luke

[andy424]

A slightly unrelated question, but still regarding keyframe in VP8, from a wireshark trace, is there a quick easy way to tell if a given VP8 frame is a key frame or not ? this way we can check to see the frequency of keyframes from a given wireshark trace.

I notice there is a recent bugzilla entry to add better support for VP8 in wireshark at a level comparable to H264

http://www.wireshark.org/lists/wireshark-bugs/201310/msg00605.html