Low Light USB Camera very dark images problem

Blue Robotics Products Cameras
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Hi!
We are using bluerobotics low light usb cams in our vehicle one at the bottom and one in the front side. The problem is when we start the software and initialize the cameras using gstreamer, the front cam sends really dark images like that. When we take the vehicle out from the water and show a strong flashlight to the front cam, its fixed after 3 -5 seconds. But approximately in 5 tries out of 10 the cam initializes dark. There is no problem in the bottom cam. We also tried changing the front cam with another spare low light usb cam and also we tried changing the camera cables but the same issue continues. Btw, if it could help we are using the mjpeg format and a jetson xavier to test it. Also, I can paste the pipeline code if it helps. Are there any settings that we could do with the pipeline to avoid this issue?

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Hi @Efe,

I’m not sure what’s going on here, although it seems like potentially some kind of issue with the camera’s auto exposure functionality, especially since it’s consistent across two different cameras of the same type. That said, I’d expect shining a bright light into the camera to possibly cause an issue like this, rather than fixing it…

Hmm, we mostly use H264 rather than MJPEG, but I don’t see how that could be related. Are you able to connect the camera directly to a desktop computer or laptop and see whether it has similar behaviour?

I don’t know that the pipeline would have much effect on this unless you’re trying to retrieve frames more quickly than the camera can capture them at. My main suggestion would be trying to turn off auto exposure in the camera settings (e.g. using v4l2-ctl) and setting a manual exposure value, and possibly trying to retrieve frames at a lower rate and/or resolution if you’re currently using high ones.

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Thanks for your response, I will try setting exposure manually. But I am also suspecting our camera cable might be causing the issue. Its not the original cable from bluerobotics and we tacked the jst and usb ends to the cables ourselves. Its almost the same length as the original cable. Do you think that it could be caused by the cable?