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Unread 12-10-2016, 20:10
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Re: Microsoft USB Camera Freezing on Pi

Quote:
Originally Posted by jreneew2 View Post
Why put sunglasses over it? Is it because the image is getting over exposed? Does that freeze the sensor somehow?
The Microsoft Lifecam 3000 and VX-6000 have some registers buried in the USB layer implementation that cause them to have white balance issues that reduce the frame rate. The OmniVision CMOS sensor they use is high end but you do not talk directly to it. It usually appears as dropped content when light sources or reflections move in the image during video analysis but it happens as well when used as a webcam (the image shudders because of the reduced capture rate).

Added to this, if you put those camera on Windows with the Microsoft driver you will get slightly better results than the generic Linux drivers via V4L and GSPCA/UVA. This again is because Microsoft has not been forthcoming with the required information as I have contacted the relevant package maintainer in the past but it would help if Microsoft could provide direction on what they did.

The retroreflective tape works best with IR light sources. If you use an IR light source and turn down the sensitivity to visible light it sticks out like a sore thumb and the sunglass tint helps reduce the visible light even more because you can not adjust the registers.

If you had say a Logitech C930 you'd get good drivers on Linux and Windows and I know they operate correctly with GRIP, V4L directly and OpenCV. It works on all embedded boards I have tried: Kangaroo, ODroid, Raspberry PI and the BeagleBone. I see no reason it would not work on the NVidia boards. It definitely works on the RoboRIO. Of course in Linux be sure to install the relevant sources/packages. With the Logitech C930 no sunglasses are required.

There are a number of detailed posts on this subject if you search the forums. I contributed to several in the past.

Last edited by techhelpbb : 13-10-2016 at 07:43.
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