How to pixelate/ hide certain regions of a camera stream?

[hydroid7]

Hi,
is there a possibility to pixelate or hide certain regions of a stream so that it does not get recorded?
Can it maybe done with some FFMPEG filters?

Thank you in advance!

[roflcoopter]

Sorry for the late reply, missed this question.
Should be possible with some FFmpeg filters yes.

Something like this came up when doing a quick google search:

ffmpeg -i input -filter:v "crop=out_w:out_h:x:y" output

Replace out_w and out_h with the width and height of the output video, and x and y with the top-left corner coordinates of the cropping area.

You can use the config option video_filters to apply it to the camera.

Dont have time right now to test it out myself, but please let me know how it works out for you!

[hydroid7]

Thank you for the suggestion, I've tried it with crop, but then I get strange artifacts on my stream. I assume it is because of the changed resolution.
Instead you can use drawbox:

video_filters:
  - drawbox=x=0:y=0:w=1920:h=200:color=black@1:t=fill
  - drawbox=x=50:y=200:w=800:h=600:color=black@1:t=fill

and it works well. You can even apply it multiple times to black out certain non-rectangular areas.

[roflcoopter]

Nice! So drawbox is working well? If so I will add it to the docs as an example

[hydroid7]

Its working really good, as I mentioned before, you can even specify multiple filters and they are easy to set up!