1. A computer-readable medium including computer-executable instructions, the computer-executable instructions comprising: instructions for obtaining a normalized value for each of a plurality of pixels, including instructions for: obtaining a first color from one of the plurality of pixels, extracting color components from the first color and a second color, determining a distance for each of the color components between the first and second colors, and combining the distances for the color components to obtain the normalized value; and at least one of: instructions for accumulating the normalized values to a generate a result, comparing the result to a threshold to determine whether a first image that includes the pixels matches a second image that includes the second color, and displaying a result of the comparison via a graphical user interface; instructions for determining whether one of the pixels that includes the first color is to be copied to a whiteboard, and displaying the whiteboard via a graphical user interface; or instructions for determining whether a third image that includes the pixels is detected as a foreground image of a fourth image that includes the second color and displaying a result of the determination via a graphical user interface.