VideoCapture limited to 20 usbcam help

asked 2015-06-28 21:33:56 -0600

mcalpinej gravatar image

Windows c++ opencv 2.49

I have a project that requires opening 25 cameras and capturing a frame. I am using Logitech c920 webcams.

I am capable of opening 20 cameras but if I try opening 21 cameras I error: Unhandled exception at 0x5eda8fe2 in Box Draw.exe: 0xC0000005: Access violation reading location 0xe436ebe3.

Linux c++ opencv 3.0

I tried Linux and the limit of webcam is 8. I error out with Linux with v4l : index # is not correct after the 8th webcam is open.

Linux and windows both see the webcams and the windows Logitech software can open each stream.

I believe there is a quick fix to both Linux and windows but I don't know where the files are to increase the camera limit to over 8 for Linux or 20 for windows.

tried editing test_video, test_video_io in windows tried editing cap_v4l in Linux

Any hints or ideas would be greatly appreciated.

edit retag flag offensive close merge delete

Comments

I just posted a solution for Linux on Stack Overflow. It looks like you were close for Linux (cap_v4l) -- my guess is you have a libv4l build and need to edit cap_libv4l.cpp instead.

Ulrich Stern gravatar imageUlrich Stern ( 2016-07-27 12:53:41 -0600 )edit