How to have the camera 'desynchronized' with Illumination changes?

asked 2020-08-03 01:50:27 -0500

vasudha gravatar image

For my current project, I have to record a video stream from a USB camera connected to Raspberry-Pi. While recording the videos if there are any illumination changes the camera should not synchronize it's preview/recording to the light change. Instead it should only record what it sees without any changes from camera input(for ex: exposure, contrast or brightness).

I tried making changes in FFMPEG config and reinstalled it but it doesn't seem to work.

I turned off auto_exposure with opencv but that wasn't useful either.

I am using OpenCV for recording the videos later from which face recognition and skin-type classification will be done. So it is important that the Face color is not altered by the camera automatically with external illumination change. Can someone please help me with this? Thanks.

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I tried making changes in FFMPEG config

no real idea about raspis, but is it really using ffmpeg for the webcam ? (rather to write videos, i'd think)

try to check by setting OPENCV_DEBUG_VIDEOIO=TRUE in the env. then it will print out the backends checked / used

berak gravatar imageberak ( 2020-08-03 08:46:44 -0500 )edit

most cams have a whitebalance thing, that should be off, too here

berak gravatar imageberak ( 2020-08-03 08:49:48 -0500 )edit