1. A method for processing an image signal, comprising: receiving an image signal that has been corrupted by one or more effects; detecting said one or more effects in said received image signal; selectively enabling one or more blocks to preprocess said image signal to compensate for said detected one or more effects, wherein said selective enabling is based on said detected one or more effects; and performing visual analysis on said preprocessed signal using background subtraction, wherein said visual analysis is performed by a processor.