Connecting Sony A7 III as webcam

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I am using Sony’s Imaging Edge to connect my mirrorless Sony A7 III to my Mac. It all works nicely and I can see it presented as a webcam on apps like Zoom. The problem arises when I try to read frames using this webcam in OpenCV by calling cv2.VideoCapture(1) instead of the default cv2.VideoCapture(0).
When I use the default Mac webcam everything works, but it doesn’t work with this camera. A standard Logitech camera has no problem with OpenCV.

The error is very strange to me. Any feedback is appreciated.

MIOMS: HardwarePlugIn_StreamCopyBufferQueue <Stream: 0x7f840111c770> (id=34) self=0x11f1086f8 queue=<CMSimpleQueue 0x7f840111e970 retainCount: 2 allocator: 0x7ff85293ad80

capacity = 30

count = 0

readIndex = 30

writeIndex = 30

elements[readIndex..(writeIndex-1) %% (capacity+1)] = {

}

>
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set some CAP_PROPs, see if that makes it go. frame width and height specifically might be important. OpenCV by default tries to get 640x480.

and perhaps set apiPreference=cv.CAP_AVFOUNDATION so the autoselection doesn’t get a chance to do anything silly… I think that’s what macos uses. if it’s not, here’s the full list for all operating systems: OpenCV: Flags for video I/O