Running VisionWorks nvx_sample_nvgstcamera_capture Use USB Camera LogitechC310 error

My Camera Information
cat /dev/v4l/by-id/*
cat: /dev/v4l/by-id/usb-046d_081b_6D1FE030-video-index0: Invalid argument

//std::string resolution = “1280x720”, input = “device:///nvcamera”;
Modify the source code to
std::string resolution = “1280x720”, input = “device:///v4l2?index=0”;

error message Can’t Open Resource

What is the reason for this?
How to solve?

Hi,

Suppose you should be able to find your camera on /dev/video*.
Could you help to check it first?

Thanks.

About whether the code of nano jetbot camera.py can modify this code to use USB camera, if you can modify it to something, I refer to this file and the modification is invalid.

https://github.com/NVIDIA-AI-IOT/jetbot/blob/master/jetbot/camera.py

def _gst_str(self):
return ‘nvarguscamerasrc ! video/x-raw(memory:NVMM), width=%d, height=%d, format=(string)NV12, framerate=(fraction)%d/1 ! nvvidconv ! video/x-raw, width=(int)%d, height=(int)%d, format=(string)BGRx ! videoconvert ! appsink’ % (self.capture_width, self.capture_height, self.fps, self.width, self.height)

Reference has tried this kind of hard to use :
https://github.com/dusty-nv/jetson-utils/blob/2fb2b9dfd8323f99c22d3e2755b88345abd2f3a8/camera/gstCamera.cpp#L351

nvcamerasrc fpsRange=“30.0 30.0” ! video/x-raw(memory:NVMM)…

I hope to give a method to support USB camera. Thank you very much.

Hi,
For USB camera, you can get all supported formats through v4l2-ctl command:

nvidia@nvidia-desktop:~$ v4l2-ctl -d /dev/video1 --list-formats-ext
ioctl: VIDIOC_ENUM_FMT
        Index       : 0
        Type        : Video Capture
        Pixel Format: 'YUYV'
        Name        : YUYV 4:2:2
                Size: Discrete 640x480
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
(...skip...)
                Size: Discrete 800x600
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
(...skip...)

And pick one mode(ex: 800x600p24) to run:

'v4l2src device=/dev/video1 ! video/x-raw, width=800, height=600, format=(string)YUY2, framerate=(fraction)24/1 ! videoconvert ! video/x-raw,format=BGR ! appsink'

I have the same error.

I try:

std::string resolution = "1280x720", input = "device:///v4l2?index=0";
desktop:~/Downloads$ v4l2-ctl --all | more
Driver Info (not using libv4l2):
	Driver name   : uvcvideo
	Card type     : HD Pro Webcam C920
	Bus info      : usb-70090000.xusb-2.4
	Driver version: 4.9.140
	Capabilities  : 0x84200001
		Video Capture
		Streaming
		Extended Pix Format
		Device Capabilities
	Device Caps   : 0x04200001
		Video Capture
		Streaming
		Extended Pix Format
Priority: 2
Video input : 0 (Camera 1: ok)
Format Video Capture:

Hi,
For running v4l2rc,you have to modify the sample code. Please refer to
https://devtalk.nvidia.com/default/topic/1051019/jetson-agx-xavier/visionworks-1-6-samples-issue/post/5337328/#5337328

I did not understand.

In the source code I use:

std::string resolution = "1280x720", input = "device:///v4l2?index=0";

What I need change ? “device:///v4l2?index=0” is for usb cam right ?

Usb cam are in /dev/video0.

I run this line and receive this error:

gst-launch-1.0 v4l2src device="/dev/video0" ! \ "video/x-raw, width=640, height=480, format=(string)YUY2" ! \ xvimagesink -e

(gst-launch-1.0:29390): GStreamer-CRITICAL **: 10:27:46.987: gst_element_make_from_uri: assertion 'gst_uri_is_valid (uri)' failed
WARNING: erroneous pipeline: syntax error