Video filter in Kurento SFU mode

[Kaiduan Xie]

Hi,

I am puzzled by how video filter works in the SFU model in Kurento.

Usually SFU does not perform video codec decoding and encoding. For video filter to work, we need un-encoded raw video. Then how video filter works in Kurento SFU mode. Can anyone explain?

Thanks,

/Kaiduan

[Neil Young]

An OpenCV filter for instance can be inserted between publisher and subscriber. The fiter is getting frame by frame in form of an OpenCV Mat delivered by KMS. After processing the frames are re-encoded in the format the subscriber(s) have negotiated with KMS. That way it is not a plain SFU, though. But works pretty well.

I'm using different filters for e.g. OpenCV calibration, barcode detection, Aruco code detection etc.

No filter, no transcoding (generally), plain fast SFU functionality.