Separation of overlapped color planes for document images

Color plane separation is very useful in processing color document images. Many reported methods take it as a multi-class classification problem and work not well in overlapped color regions. This paper proposed a simple but effective linear projection based method for separating overlapped color planes. The separation task is taken as a probability problem, i.e., in the output plane, target color should have high response and the other colors should have low response, or vice versa. Furthermore, it assumes that the number of foreground colors is low, typically one to four, and overlapped areas contain mixed colors instead of opaque covering. Experimental results demonstrate the effectiveness and flexibility of our method.