1. A method to identify regions in images, the method comprising: receiving an image of a scene of real world; one or more processors computing an attribute based on pixel intensities in the image; the one or more processors using the attribute to identify at least one input to be used in processing the image to identify at least one maximally stable extremal region therein, wherein the at least one input is one of (A) a parameter used in said processing or (B) a portion of the image to be subject to said processing or both (A) and (B); the one or more processors performing said processing to identify said at least one maximally stable extremal region based on said at least one input; wherein said processing comprises at least comparing a difference in intensities of a pair of pixels in the image to a predetermined limit, adding to a list, a pair of coordinates of a pixel in said pair of pixels, in response to finding said predetermined limit is exceeded, and repeating said comparing and said adding; and the one or more processors storing in one or more memories, the list as a representation of the at least one maximally stable extremal region identified by said processing.