1. Apparatus for filtering non-text information from a an image containing text, the apparatus comprising: a storage device for storing an image; and a processor configured to: identify a text color, being a color of text in the image; select from a plurality of candidate multi-color-channel color spaces a text color space having a color channel that is close in color to the text color; represent the image as a plurality of cells in the selected text color space, each cell having a value represented as one or more bits of data for each of the color channels in the text color space; and, for each cell, remove non-text color channels and retain the text color channel.