Data Collection for Camera intrinsic Calibration

Calibration Target:

Checkerboard is the calibration target. Any checkerboard of different sizes and different internal corners can be used. Eg: You can use the following attached pdf. It has 7 internal corners horizontally and 9 internal corners vertically. https://drive.google.com/file/d/1mTR8HTpvROE1Pv0rmXEBVLSxs_yMDnvf/view?usp=sharing

Data for camera intrinsic and distortion calibration

Take checkerboard shots so that the image's entire field of view is covered by checkerboards. These checkerboards should be placed roughly at 1.5 - 2m away from the camera (these checkerboards does not have to be placed on the ground). You do not have to achieve this in a single shot. You can take multiple shots with different checkerboard locations. As long as any pixel in the field of view is covered by at least one checkerboard in some shot, it is enough. In addition, the checkerboards should be tilted slightly in different directions for each image.

This set is to estimate camera matrix and distortion parameters, so there is no need to record the lidar data. The boards and camera should be static while taking the images. Do not move the boards or camera while taking the images. Also, do not hold the checkerboard by hand to minimize blur due to shaking.

You can also use a computer monitor instead of a physical checkerboard for intrinsic calibration. Monitors are very accurate and flat. You can show this PDF file on the monitor for calibration.

For example, please take images like the following. Example 1:

Example 2: