how to generate 'lookup table' of the distortion by 'Gimp' or 'PhotoShop'

[TheXiong]

ImageMagick version

6

Operating system, version and so on

windows 10

Description

https://legacy.imagemagick.org/Usage/mapping/

As an image is used for the 'lookup table' of the distortion, you can create, or modify a the distortion map using an image editor, such as 'Gimp' or 'PhotoShop', giving you the freedom to do some really fancy and complex distortions.

[fmw42]

Perhaps you might show us some examples.