Issue with allocating USB bandwidth for 2 USB cameras in Orange pi 5+

[John151235]

I am trying to stream multiple USB cameras in Orange pi 5+, but I am getting the error:

ffmpeg -f v4l2 -input_format mjpeg -video_size 640x480 -i /dev/video3 -c:v copy output2.mp4 # One process successfully started, but calling this  a second time doesn't work:

...

[video4linux2,v4l2 @ 0xaaab1ddcdbc0] ioctl(VIDIOC_STREAMON): No space left on device
/dev/video3: No space left on device

 

dmesg displays this:

[696321.331182] usb 5-1.3.2: Not enough bandwidth for new device state.
[696321.331189] usb 5-1.3.2: Not enough bandwidth for altsetting 7

I initially assumed that this was a hardware issue, but the device is able to successfully stream camera's maximum resolution 1920x1080 in raw video format, but fails to stream 2 cameras at 640x480 in MJPEG resolution.

It is clear that number of bits that the bus can transfer per second is not the cause of the issue.

Does anyone know what the issue may be?

[robertoj]

This is an artificial limitation on the linux uvc driver, which handles webcams

 

Try connecting the 2nd webcam in a port in a different USB root inside your orange pi.

 

Or try following this guide https://www.thegoodpenguin.co.uk/blog/multiple-uvc-cameras-on-linux/