[Freeswitch-users] Detect video presence in mod_conference

Hello, I am looking for a mechanism to detect whether the user that currently holds the conference video floor is actually sending a video stream or not. So far I know that the variable CF_VIDEO may be used to check if the channel is video capable, either to send and/or receive video. But this is not enough to ensure that a user is sending video, just if he is able to send and/or receive video. My idea is to check if there are video packets flowing through FS, that would mean that the user holding the floor is sending video. Is there a better way to do this? If not, where would be the best place to monitor the video packets flow? Thanks!