Jetpack 4.2.2 USB webcam very low framerate

Hi all, we have a Logitech C920 hooked up to a TX2 which is suffering from 100% CPU usage and 2-3 FPS when viewing the camera feed via video-viewer /dev/video0

The v4l2-ctl list formats command indicates the camera only supports YUYV & MJPG.

I’m assuming this level of performance means we’re missing something, as the TX2 is more capable than this for simply viewing a camera feed

hello mac27007,

could you please also share the format reports by v4l2 standard controls,
for example,

$ v4l2-ctl -d /dev/video0 --list-formats-ext

you may have access camera stream to ensure the frame-rate output from sensor side,
please using v4l2 standard controls to access sensor stream, it’ll also report average fps.
for example,

$ v4l2-ctl -d /dev/video0 --set-fmt-video=width=1920,height=1080,pixelformat=MJPG --stream-mmap --stream-count=100

besides,
please also share your commands which is suffering from 100% CPU usage and 2-3 FPS for reference.
thanks

Hi Jerry, thanks for that.

Any of the 1280x720 camera feed commands such as the below cause the low framerate (2-3 FPS). Running the command with either codec (YUYV or MJPG) at 640x480 runs fine at 30 FPS

$ video-viewer --input-width=1280 --input-height=720 --input-codec=MJPG /dev/video0
OR
$ video-viewer /dev/video0

v4l2-ctl -d /dev/video0 --list-formats-ext provides the below

mic-720ai@ubuntu:~$ v4l2-ctl --device /dev/video0 --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)
	Size: Discrete 160x90
		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)
	Size: Discrete 160x120
		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)
	Size: Discrete 176x144
		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)
	Size: Discrete 320x180
		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)
	Size: Discrete 320x240
		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)
	Size: Discrete 352x288
		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)
	Size: Discrete 432x240
		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)
	Size: Discrete 640x360
		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)
	Size: Discrete 800x448
		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)
	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)
	Size: Discrete 864x480
		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)
	Size: Discrete 960x720
		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)
	Size: Discrete 1024x576
		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)
	Size: Discrete 1280x720
		Interval: Discrete 0.100s (10.000 fps)
		Interval: Discrete 0.133s (7.500 fps)
		Interval: Discrete 0.200s (5.000 fps)
	Size: Discrete 1600x896
		Interval: Discrete 0.133s (7.500 fps)
		Interval: Discrete 0.200s (5.000 fps)
	Size: Discrete 1920x1080
		Interval: Discrete 0.200s (5.000 fps)
	Size: Discrete 2304x1296
		Interval: Discrete 0.500s (2.000 fps)
	Size: Discrete 2304x1536
		Interval: Discrete 0.500s (2.000 fps)

Index       : 1
Type        : Video Capture
Pixel Format: 'MJPG' (compressed)
Name        : Motion-JPEG
	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)
	Size: Discrete 160x90
		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)
	Size: Discrete 160x120
		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)
	Size: Discrete 176x144
		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)
	Size: Discrete 320x180
		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)
	Size: Discrete 320x240
		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)
	Size: Discrete 352x288
		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)
	Size: Discrete 432x240
		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)
	Size: Discrete 640x360
		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)
	Size: Discrete 800x448
		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)
	Size: Discrete 800x600
		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)
	Size: Discrete 864x480
		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)
	Size: Discrete 960x720
		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)
	Size: Discrete 1024x576
		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)
	Size: Discrete 1280x720
		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)
	Size: Discrete 1600x896
		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)
	Size: Discrete 1920x1080
		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)

And $ v4l2-ctl -d /dev/video0 --set-fmt-video=width=1920,height=1080,pixelformat=MJPG --stream-mmap --stream-count=100 outputs the below (it doesn’t start a camera feed, just outputs in the terminal)

mic-720ai@ubuntu:~$ v4l2-ctl -d /dev/video0 --set-fmt-video=width=1920,height=1080,pixelformat=MJPG -- 
stream-mmap --stream-count=100
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< 30.09 fps
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< 30.19 fps
<<<<<<<<<<<<<<<<<<<<<<<<<<<<< 29.80 fps
<<<<<<<<<

hello mac27007,

please use gstreamer pipeline with v4l2src instead of video-viewer to preview sensor streams,
for example,

$ gst-launch-1.0 -v v4l2src device=/dev/video1 ! video/x-raw,framerate=30/1,width=640,height=480 ! xvimagesink

or,
here’s commands to disable preview frames and shows frame-rate only.

$ gst-launch-1.0 v4l2src device=/dev/video1 ! "video/x-raw, format=(string)YUYV, width=(int)1920, height=(int)1080" ! fpsdisplaysink text-overlay=0 video-sink=fakesink sync=0 -v

Hi @mac27007, that is kind of strange that your Logitech C920 doesn’t list H264 format - I have two C920’s that do. They work smoothly in H264 @ 1080p30.

Anyways, after you verify that you can view the stream standalone with the GStreamer pipeline that @JerryChang provided, you can try the video-viewer again (getting video-viewer to work will make sure that imagenet/detectnet/ect work with your camera as well):

$ video-viewer --input-codec=raw --input-width=640 --input-height=480 /dev/video0

Raw (YUYV) format will only get you so fast since C920 is a USB2 device. My guess is that the MJPEG decoding is hanging you up somewhere. Try changing line 181 of jetson-inference/utils/camera/gstCamera.cpp from nvjpegdec to jpecdec and see if that helps:

// ss << "nvjpegdec ! video/x-raw ! ";
ss << "jpegdec ! video/x-raw ! ";

Then re-run the following commands to compile/re-install:

$ cd jetson-inference/build
$ make
$ sudo make install

Then try running video-viewer again in MJPEG mode:

$ video-viewer --input-codec=mjpeg --input-width=1280 --input-height=720 /dev/video0

Thanks @JerryChang & @dusty_nv

 $ gst-launch-1.0 -v v4l2src device=/dev/video0 ! video/x-raw,framerate=30/1,width=640,height=480 ! xvimagesink

Runs fine and the framerate is smooth - interestingly substituting in 1280x720 doesn’t work, and the process stops (unsure if it’s meant to without changing other parameters)

However running and tweaking $ video-viewer --input-codec=raw --input-width=640 --input-height=480 /dev/video0 produces some interesting results, using 1280x720 and input-codec=raw, I get around 10 FPS (and approx. 20% CPU usage). Changing raw to MJPEG cuts the FPS down to around 2-3 (still at 1280x720) and has the CPU at 100%

The good news is changing nvjpegdec to jpecdec seems to have worked!

$ video-viewer --input-codec=mjpeg --input-width=1280 --input-height=720 /dev/video0

Now runs smoothly at 30 FPS

Interestingly on the C920, I heard rumors that Logitech removed the H264 capabilities

Many thanks!

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