1. An article of manufacture comprising a non-transitory computer-readable medium with instructions encoded thereon, the instructions configured to cause one or more processors to perform a method comprising: receiving an image of a sequence of glyphs; for each of a subset of glyphs of the sequence: determining whether the glyph matches a retained glyph; assigning to the glyph a character identity associated with the retained glyph in response to determining that the glyph matches a retained glyph; retaining the unmatched glyph, selecting a character identity for the unmatched glyph, and assigning the selected character identity to the unmatched glyph in response to determining that the glyph does not match a retained glyph; generating a representation of the image of the sequence of glyphs with the assigned character identities; and identifying the sequence of glyphs using the generated representation.