Image Processing: What are occlusions?

Question

I\'m developing an image processing project and I come across the word occlusion in many scientific papers, what do occlusions mean in the context of i

Answer 1

As the other answers have explained the occlusion well, I will only add to that. Basically, there is semantic gap between us and the computers.

Computer actually see every image as the sequence of values, typically in the range 0-255, for every color in RGB Image. These values are indexed in the form of (row, col) for every point in the image. So if the objects change its position w.r.t the camera where some aspect of the object hides (lets hands of a person are not shown), computer will see different numbers (or edges or any other features) so this will change for the computer algorithm to detect, recognize or track the object.