I am using the webrtcbin janusvideoroom demo. I can successfully publish vp9 video to a janus video room. My expectation is that the following VP9 settings should give me a CBR encoding. ‘end-usage=1’ is CBR. I have a defined kreyframe rate.
What I see is that on average, my bitrate oscillates around +/-25% of the target-bitrate which I understand as true CBR doesn’t exist. However, in scene changes where I go from black to regular content, the encoder bit rate goes up to almost twice the bitrate. The image freezes, because the encoder is sending a flurry of packets, and frames are then dropped (I don’t know if this is the encoder or janus). It is repeatable. Even when I capture a static frame, the encoder output vacillates wildly - it goes as low as 1800 kbps to as high as 5500 kbps on a parked frame.