Problems with camera distortion correction

Elusive

I modified rgb_undistort.py to perform aberration correction for 4 cameras, but one of the images after aberration correction has non-removable chunks, resulting in problems with the displayed image. Also during my modification I found that only the first few frames of the video can be displayed in real time, after that the image is no longer captured, the screen remains motionless. Looking forward to a solution。

jakaskerl

Hi @Elusive
Looks like a pole was created when correcting the image. Do cameras (cam_test.py) work as expected and is this only present once correction is done?

Could you add a MRE of this code.

Thanks,
Jaka

Elusive

It is normal to run it in the same_test.py, only the rgb_undistort.py run will have this problem, the graphs before and after the correction are shown below. Then I show my modified rgb_undistort.py file, you please take a look.

jakaskerl

Hi @Elusive
It looks like a mesh issue. What about taking the rectified output of the stereo depth node? The image there is rectified and undistorted and should't have any flying orbs.

Thoughts?

Elusive

Can you be more specific about how to call the rectified output of the stereo depth node? I think I've used it before, but I can only get the corrected greyscale image right?

jakaskerl

Hi @Elusive
Yes, it is grayscale only.

stereoNode.rectifiedLeft.link(XoutLeft)
stereoNode.rectifiedRight.link(XoutRight)

What about the automatic undistortion that can be done with camera node? If you set camera.setMeshSource(dai.CameraProperties.WarpMeshSource.CALIBRATION).

Thoughts?

Elusive

I'm still mainly trying to get the result after the distortion correction of the color camera.When I run the code .camera.setMeshSource(dai.CameraProperties.WarpMeshSource.CALIBRATION), I can get the result of the aberration correction as shown in the previous image. But there will be non-removable spherical shape in cam_B.

jakaskerl

Hi @Elusive
Could you save the calibration you have right now, then try to recalibrate the device using https://docs.luxonis.com/projects/hardware/en/latest/pages/guides/calibration/. Issue with undistortion with the current mesh you are using seems to stem from a faulty calibration.

Thanks,
Jaka