Hello! I’m using a See3Cam CU81 4k camera which supports MPEG and UYVY for video capture. I am on a Windows laptop.
When I capture a 4k video using Windows’ built-in Camera app, I do not see any banding on the video. The videos from the Camera app are capture as .mp4.
If I try to display live 4k video from the camera with imshow in OpenCV, I get banding. There is no banding at HD and FHD. It’s possible I just need to download a different video capture codec for OpenCV to use. The only ones that work are:
cap = cv.VideoCapture(1, cv.CAP_DSHOW), cap = cv.VideoCapture(1), and cap = cv.VideoCapture(1, CAP_ANY)
All other specifications I’ve tried have resulted in the camera not being able to be opened. i.e.
if not cap.isOpened():
print(“Cannot open camera”)
exit()
I tried displaying the video capture info as much as possible with cap.get(cv.CAP_PROP_***) manually entering in various things like cv.CAP_PROP_MODE, CAP_PROP_FORMAT, etc.
For HD and FHD I got:
Exposure: -5.0
Mode: -1.0
Format: -1.0
Fourcc: 1498831189
FPS: 0.0
ISO Speed: -1.0
Settings: 0.0
Buffer Size: -1.0
Codec Pixel Format: -1.0
and for 4k I got:
Exposure: -5.0
Mode: -1.0
Format: -1.0
Fourcc: -466162819
FPS: 0.0
ISO Speed: -1.0
Settings: 0.0
Buffer Size: -1.0
Codec Pixel Format: -1.0
I’m unsure if there’s a setting that exists that I just need to use to correctly interface with the camera (as it can capture 4k video without banding in other applications) or if I’ll need to download a new codec and set that up with OpenCV. The banding is caused by fluorescent lighting which I verified by recording with those lights turned off. Interestingly the Fourcc code associated with the HD and FHD displays corresponded to the UYVY encoding the camera supported. Haven’t been able to find anything for the negative value in the 4k.
Some other things I’ve tried:
-Eliminated a waitKey() delay
-Changed the FPS of the capture from 5 fps all the way up to 120 fps
Any help would be appreciated. I’ll delete this if it’s too similar to something else. I’ve been rooting around for a few hours now and haven’t seen anything that matched this exactly. There was one post on a different forum website I believe about how someone had trouble displaying 4k video with an MPEG encoding in the OpenCV video display but had no trouble with videos with different encodings.
I’m pulling up the 4k display by doing:
cap.set(cv.CAP_PROP_FRAME_WIDTH, 3840)
cap.set(cv.CAP_PROP_FRAME_HEIGHT, 2180)