AGX support 2 USB cameras only?

[AK51]

Hi, I found out I couldn’t run 4 USB cameras at the same time.

When I run 4 simple opencv code in four terminal, only 2 can run.

Note: individual code works fine. Only 1280 x 720 30 fps each 480M. And I connect each USB camera in separate 4 plug in AGX.

Is there any settinng I can change it? Thx

import cv2# current camera
cap = cv2.VideoCapture(0)
while (cap.isOpened()):
   ret, frame = cap.read()
   cv2.imshow('frame', frame)   
   key = cv2.waitKey(1)
   # ESC
   if key == 27:
      breakcap.release()
cv2.destroyAllWindows()

import cv2# current camera
cap = cv2.VideoCapture(2)
while (cap.isOpened()):
   ret, frame = cap.read()
   cv2.imshow('frame', frame)   
   key = cv2.waitKey(1)
   # ESC
   if key == 27:
      breakcap.release()
cv2.destroyAllWindows()
```

import cv2# current camera
cap = cv2.VideoCapture(4)
while (cap.isOpened()):
   ret, frame = cap.read()
   cv2.imshow('frame', frame)   
   key = cv2.waitKey(1)
   # ESC
   if key == 27:
      breakcap.release()
cv2.destroyAllWindows()

import cv2# current camera
cap = cv2.VideoCapture(6)
while (cap.isOpened()):
   ret, frame = cap.read()
   cv2.imshow('frame', frame)   
   key = cv2.waitKey(1)
   # ESC
   if key == 27:
      breakcap.release()
cv2.destroyAllWindows()

lsusb -t
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=tegra-xusb/4p, 10000M
    |__ Port 3: Dev 2, If 0, Class=Hub, Driver=hub/4p, 10000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=tegra-xusb/4p, 480M
    |__ Port 3: Dev 2, If 0, Class=Wireless, Driver=rtk_btusb, 12M
    |__ Port 3: Dev 2, If 1, Class=Wireless, Driver=rtk_btusb, 12M
    |__ Port 4: Dev 3, If 0, Class=Hub, Driver=hub/4p, 480M
        |__ Port 3: Dev 5, If 0, Class=Hub, Driver=hub/4p, 480M
            |__ Port 2: Dev 7, If 0, Class=Hub, Driver=hub/4p, 480M
                |__ Port 1: Dev 25, If 0, Class=Video, Driver=uvcvideo, 480M
                |__ Port 1: Dev 25, If 1, Class=Video, Driver=uvcvideo, 480M
        |__ Port 1: Dev 24, If 0, Class=Video, Driver=uvcvideo, 480M
        |__ Port 1: Dev 24, If 1, Class=Video, Driver=uvcvideo, 480M
        |__ Port 4: Dev 20, If 0, Class=Video, Driver=uvcvideo, 480M
        |__ Port 4: Dev 20, If 1, Class=Video, Driver=uvcvideo, 480M
        |__ Port 2: Dev 4, If 0, Class=Hub, Driver=hub/4p, 480M
            |__ Port 3: Dev 22, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M
            |__ Port 1: Dev 6, If 0, Class=Hub, Driver=hub/4p, 480M
                |__ Port 1: Dev 26, If 0, Class=Video, Driver=uvcvideo, 480M
                |__ Port 1: Dev 26, If 1, Class=Video, Driver=uvcvideo, 480M
            |__ Port 4: Dev 21, If 1, Class=Human Interface Device, Driver=usbhid, 1.5M
            |__ Port 4: Dev 21, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M

v4l2-ctl -d /dev/video0 --list-formats-ext
ioctl: VIDIOC_ENUM_FMT
	Type: Video Capture

	[0]: 'MJPG' (Motion-JPEG, compressed)
		Size: Discrete 640x480
			Interval: Discrete 0.040s (25.000 fps)
		Size: Discrete 1280x720
			Interval: Discrete 0.040s (25.000 fps)
	[1]: 'YUYV' (YUYV 4:2:2)
		Size: Discrete 640x480
			Interval: Discrete 0.033s (30.000 fps)
		Size: Discrete 1280x720
			Interval: Discrete 0.100s (10.000 fps)

I found this, I am surprised that two 10Gps USB can not support 4 USB cameras… Is it true?

connected more than two usb cameras problem on deepstream-app (Jetson Nano Dev Kit)

Hi, With further investigation, we found bandwidth limitation is hit in using USB2(High-Speed) cameras. High-Speed limit is 480Mbps. In the test, two E-Con See3CAM_CU135 are USB3(Super-Speed) cameras. Please use USB3 cameras to get 5Gbps bandwidth.

And I saw this, but it said it can brick the Jetson…. I am scared to try unless it is working. And the file name does not match… Thx

Configure UVC Video Driver for multiple ( > 2) web cameras

Hello all, I am working on a project to get 360 degree vision with the use of 6 USB cameras. I am wanting to stream all 6 at once. I understand that the main limitation for this is USB hub bandwidth. I have enabled USB3.0 for my TK1 which has allowed me to stream 2 cameras at once, but not more. Poking around on the web, it appears that there is a quirk that can be configured with the UVC video driver to better manage USB hub bandwidth http://stackoverflow.com/questions/25619309/how-do-i-e…

[DaneLLL]

Hi,
If you use AGX Xavier developer kit, would suggest connect two cameras to the type-A port and two cameras to the type-C port through USB hub. And please use USB3 cameras and USB3 hub. If either device is a USB2 device, total bandwidth is 480Mbps instead of 5Gbps.

[AK51]

Hi, is there any way the AGX can support 4 USB cameras? I guess mine is USB2 only. Can I force to reduce the resolution or fps? thx

I have tried to release the cap.capture and do it for another camera, it kind of work but the speed is really slow.

I have tried to set the resolution to 320x240 in my opencv python code but the third camera still fail to get frame. Is there any way I can do it in system level? thx

[DaneLLL]

Hi,
There is a hacking solution from community:
Failed to allocate memory for four usb cameras - #4 by fabian.solano

It is not recommended but you may try.

[AK51]

Dear DaneLLL,

It is a broken link…. ERROR: The request could not be satisfied.

Anyway, it seems there is no way AGX can support more that 2 x USB2.0 cameras.

Plan B: I may use a Jetson nano to feed two USB cameras and output the rtsp streams. In this way, the openCV shall be able to get 2 rtsp streams and 2 USB cameras. Thx