V4L2 on Jetson TX2

Thanks JerryChang!
That worked!

I am writing a video with

nvgstcapture -m 2 -k 2 -w 10

Is there a chance to use autofocus to increase the quality ?

Recorded sample:
https://drive.google.com/file/d/0B86kh-1GJW29T3ItOG1CYnJZZm8/view?usp=sharing

is there a way to get the video captured with guvcview?

ed to query video capabilities: Inappropriate ioctl for device
libv4l2: error getting capabilities: Inappropriate ioctl for device
V4L2_CORE: ERROR opening V4L2 interface for /dev/v4l-subdev0
Failed to query video capabilities: Inappropriate ioctl for device
libv4l2: error getting capabilities: Inappropriate ioctl for device
V4L2_CORE: ERROR opening V4L2 interface for /dev/v4l-subdev1
V4L2_CORE: Unable to find parent usb device.V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device

@Andrey
The onboard reference sensor didn’t have focus. Does your sensor module have focus?

You can try follow below thread to use video loopback

https://devtalk.nvidia.com/default/topic/988447

Thank you for sharing the link.
I’ve separated the question into a separate thread https://devtalk.nvidia.com/default/topic/1019504/jetson-tx2/how-to-create-loopback-device-for-nvcamerasrc-for-tx2-/

ShaneCCC:
finally it created /dev/video0 device with the method [partially working]

# aptitude install v4l2loopback-source module-assistant
# module-assistant auto-install v4l2loopback-source

Is there any chance to redirect signal from the onboard camera to the /video0 device for it can be used with ordinary internet browser as a camera?

finally I managed to get it that way with supplied by colleague .ko file:

insmod v4l2loopback.ko devices=10
root@tegra-ubuntu:/home/nvidia/v4l2loopback# ls /dev/video* -l
crw-rw----+ 1 root video 81,  2 Sep  6 19:31 /dev/video0
crw-rw----+ 1 root video 81,  3 Sep  6 20:51 /dev/video1
crw-rw----+ 1 root video 81,  4 Sep  6 20:51 /dev/video2
crw-rw----+ 1 root video 81,  5 Sep  6 20:51 /dev/video3
crw-rw----+ 1 root video 81,  6 Sep  6 20:51 /dev/video4
crw-rw----+ 1 root video 81,  7 Sep  6 20:51 /dev/video5
crw-rw----+ 1 root video 81,  8 Sep  6 20:51 /dev/video6
crw-rw----+ 1 root video 81,  9 Sep  6 20:51 /dev/video7
crw-rw----+ 1 root video 81, 10 Sep  6 20:51 /dev/video8

now the issue is to make the flow from the onboard camera to be present at one of the created virtual devices

Hi JerryChang

when I input v4l2 cmmand , prompt system can not support , how can I add v4l2-ctl moudles

v4l2-ctl -d /dev/video0 --stream-mmap --stream-count=1 --stream-to=test.raw

-bash: v4l2-ctl: command not found

B/R

I would use insmod + v4l2loopback. I do use it actually. It returned the only way I can work with v4l2.
Regards
v4l2kernel.tar.gz (254 KB)

You can try install the v4l-utils or get the source from below link to build it yourself.

https://launchpad.net/ubuntu/xenial/+source/v4l-utils

thanka alot

how to make nvgstcapture back to normal from upside-down?

try the ro:2 for the rotate 180 degrees.

like that?

nvgstcapture -m 2 -k 2 -w 10 ro:2

it wont affect the rotation that way as it seems to me

Try below command.

nvgstcapture --orientation=2

thank you

nvgstcapture --orientation=0

did the trick

Hey ShaneCCC,

i try to run yolo dakrnet with the onboard cam of a jetson tx2 flashed with JetPack 3.2.
But it gives me the following video signal error:

VIDEOIO ERROR: V4L2: Pixel format of incoming image is unsupported by OpenCV
Couldn't connect to webcam.
: Invalid argument
darknet: ./src/utils.c:253: error: Assertion `0' failed.
Aborted (core dumped)

Do you have an idea what to put behind the darknet command as proper video signal?

./darknet detector demo cfg/coco.data cfg/yolo.cfg yolo.weights <video file>