Rectangle recognition

Question

Video processing

In a webcam image (live), you want to determine at what angle the large white rectangles are.

There can be several of them in the image, then everyone will be at the same angle; or maybe not at all. Well, as befits a webcam, there will be noise in the image, slight perspective distortion, color distortion depending on the light, and all that.

In which direction to start googling? OpenCV opened, did not find intelligible documentation, closed. Does she know how to do that? Or some other ready made library?

Answer 1

Opencv has just an example for finding rectangles - squares.cpp

Answer 2

What do you mean by clear documentation? :)
OpenCV's documentation is more than excellent.
You may not know how right away, but it's not so difficult to teach.

Answer 3

Remove noise with gauss blur

Answer 4

Using the Hough transform