Colors are an integral part of modern computer graphics. Monochrome is basically a two color scheme. RGB (additive primaries) are used for monitor displays. CMY (subtractive primaries) are used for hardcopy devices printing on white. Grayscale is a scheme employing various intensities of white. A common problem with colors is that there are a different number (usually fewer) available for display than there are in the image itself.

Two methods of printing a color image using a B/W printer were discussed. Threshold values are used where everything above is rendered black and the rest is left white. This can lose a lot of detail. Another method is dithering, which loses resolution by employing varying intensities. The dither pattern is always square and composed of just two colors at a time.

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