Xavier-NX: Unexpected behavior with Auto Exposure and exposure value not return correct result using v4l2-ctl

Autonomous Machines Jetson & Embedded Systems Jetson Xavier NX
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1

Hi,
I’m using Xavier-nx with Jetpack 5.0.2, and have a sensor on /dev/video1 and can be streamed and controlled using v4l2-ctl.
I try Auto Exposure properties supported by v4l2 and witness some problems. I’m able to change auto_exposure_min and auto_exposure_max in auto exposure mode (exposure_auto = 0). But the value of exposure is not change. Moreover, I can see that the image is changing when I change the max/min auto_exposure, but the exposure value I get is still unchanged.
Here is the command I use to set auto exposure properties:
exp_setting
The image when I set min and max exposure to 200000:

ex_0.1ms-0.1ms
ex_0.1ms-0.1ms1147×753 86.5 KB

And also the image when I set max exposure to higher value:
ex_0.1ms-1ms
ex_0.1ms-1ms1148×755 66.3 KB

But the exposure value is still 983919 as showed in the first image. I can set the exposure manually in both auto and manual mode, which I suppose it should be able to change only in manual mode.
I want to know is the auto exposure work correctly? If not, how can I fix it?
I attach the v4l2-ctl --all of my sensor driver for reference.
sensor_driver_info_v4l2.txt (5.6 KB)
Best regard,
Dat

3

It’s USB camera?
Looks like the exposure is limit by exposure_auto_max.
You can try a value less than 2000000 to confirm.

4

You can see on the first image I attach I set exposure_auto_max to 200000 and confirm with v4l2-ctl -C exposure_auto_max to ensure that it is set to 200000. But the exposure when I get using v4l2-ctl -C exposure is 983919, which is bigger than exposure_auto_max.

5

Try v4l2-ctl -c exposure=1900000
What the v4l2-ctl --all?

6

Try v4l2-ctl -c exposure=1900000
What the v4l2-ctl --all?

7

yes, I can set manual exposure with v4l2-ctl -c exposure=1900000 or with any value that I want. But I can set exposure in both exposure_auto = 0 and 1. Compare to other camera that I use, exposure can only be adjust when exposure_auto = 1.
Result of v4l2-ctl --all I have attach in sensor_driver_info_v4l2.txt file above.

8

It’s confuse!!

10

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