Question Get rectangles from pixels

[demarkr]

I am making a game, And I want to be able to draw a level in photoshop. And the game to read it.

For this, I need a way to determine what are rectangles in a picture.

For example, I have this kind of picture:


And I want the program to realize what is a rectangle, What it's size and position.
Like this:
(Rectangles highlighted in red.)

I thought about using a For loop for each Y value. And reading the green pixels one by one. But I just can't figure out the logic. And my head hurts when I think about it too much.
Any genius that can help me?

 

[Tosa]

I've never worked with it but you might want to check out the Emgu project, if you download the source then this project: Emgu.CV.Example\ShapeDetection\ should indicate how to detect shapes using their library.
https://sourceforge.net/projects/emgucv/

 

[demarkr]

I've never worked with it but you might want to check out the Emgu project, if you download the source then this project: Emgu.CV.Example\ShapeDetection\ should indicate how to detect shapes using their library.
https://sourceforge.net/projects/emgucv/

Thank you for the suggestion!
I tried it and it is not quite the result I wanted.

It only captured the lines for some reason.