Computer Vision, Artificial Intelligence, Deep Learning, Machine Learning.
(grayscale) can be thought of as a function that takes in a pixel coordinate and gives the intensity at that pixel. It can be written as function f: ℝ² → ℝ that outputs the intensity at any input point (x,y). The value of intensity can be between 0 to 255 or 0 to 1 if values are normalized. Fig. 7: