[FFmpeg-user] Change device setting from CLI?

[Steve Russell]

I bought an HD webcam during the pandemic and it's been pretty good except the colours were a bit off. I finally decided to try and do something about it. The app I use most with it (Zoom) doesn't offer any way to tweak the camera settings so, after a search, I found that FFmpeg can do the job. If I run this command:

ffmpeg-5.0.1-full_build\bin\ffmpeg -f dshow -show_video_device_dialog true -i video="HD Web Camera"

I get a dialog that lets me change several settings. Simply dropping the saturation down to about 60 does the trick but the change doesn't stick - I assume Zoom is resetting the camera when it starts up. To avoid having to manually set the saturation as above, it would be great to have a command line to change the setting. I've experimented with:

ffmpeg-5.0.1-full_build\bin\ffmpeg -f dshow -i video="HD Web Camera" -vf eq=saturation=0.6 output

but this runs without changing the appearance in Zoom. I'm guessing that this is because I'm putting the filter in between the camera and "output" rather than changing the device settings directly.

I've dug around in the documentation but find it somewhat overwhelming and don't really know where to start looking. Any pointers gratefully received!

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Regards, Steve