That looks really interesting! Thanks a lot, I'll have a look at it! Besides daily checking, I managed to overlook ALL the replies ... sorry for my late answer and thanks a lot for yours!
OBS is not an option since everything is done automatically / from command-line (and afaik OBS transcodes what would additionally overburden the small machine). It needs to be light and reliable. For now, I came up with the nginx rtmp plugin that, used as a local loopback device, now acts as a multiplexer. Two mutually exclusive systemd services forward the respective rtsp stream to the nginx server and ffmpeg records from it. That way, by starting one or the other service, I switch the stream. The starting of the two services is bound to the two corresponding arrow keys of a simple Logitech R400 presenter via xbindkeys (the remaining two keys toggle a recording and a YouTube live-stream). They are present in abundance at the institute and the setup is practically free of cpu usage even on this weak machine. That way, the lecturer can switch between blackboards / cameras and fully control the procedure just via the presenter. Best regards, Stephan Monecke -- Sent from my mobile device. Please excuse my brevity. Am 24. April 2020 21:56:12 MESZ schrieb Edward Park <[email protected]>: >Hi, > >> How can this be done with FFmpeg? Do you have an example? I know how >commands / sendcmd works. The opacity could be toggled, or the >streamselect filter could be used. But where does the switching signal >come from, while FFmpeg is running? > > >The specific messaging protocol/method would depend on a variety of >factors including personal preference, but to parrot an example given >in the manual using zmq, > >% ffmpeg -i INPUT -filter_complex >'null[main];movie=INPUT2,zmq,lumakey@toggle=tolerance=1,[main]overlay,realtime' >OUTPUT > >and sending commands to the named lumakey filter would mimic toggling >between the two streams if they were the same size and position. >i.e. using the zmqsend example program, > >% zmqsend <<<"lumakey@toggle tolerance 0" > >Regards, >Ted Park > >_______________________________________________ >ffmpeg-user mailing list >[email protected] >https://ffmpeg.org/mailman/listinfo/ffmpeg-user > >To unsubscribe, visit link above, or email >[email protected] with subject "unsubscribe". _______________________________________________ ffmpeg-user mailing list [email protected] https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
