Well, I'm studying bitmaps, and I downloaded a pdf which said that an image was an array of pixels. Since it is an array (which is quite logical) there is how to define points within the image, mark a region so to speak. The bitmap class as well should know how to read the properties of an image, such as the "size" of it, I would like to know if there is any way to mark points like 200x200 (example) and save that region into a new image. >
The image of Braum, a character in the League of Legends game, is random and this mark in black is to show what this region means.
Ps: Thank you Renan, your response helped a lot, I decided to change the question so that it would remain open and more answered.