What does cpselect do? and what are the potential applications and uses of it? (Any examples please)

I came across the function (cpselect) and i didn't exactly what the use of it. I select some points in the two images. And I want to know how can I make the best use of it.

Is there any useful applications of this function?

[Walter Roberson]

https://www.mathworks.com/help/images/ref/cpselect.html

[Steven Lord]

There are four examples in the documentation that use cpselect. While one of them seems more pedagogical (teaching about geometric transformations) the other three seem like "useful applications."