15. A system comprising: a memory configured to store an image file representing an image comprising text; and a processing device coupled to the memory, the processing device configured to: determine a plurality of portions of the image respectively corresponding to a plurality of letters of the text; determine, for a first letter of the plurality of letters, a set of letter properties comprising at least one dependent letter property, wherein each of the at least one dependent letter property is dependent on another letter of the plurality of letters; and classify the first letter into one of plurality of letterform classes based on the set of letter properties.
17. The system of claim 15 , wherein the at least one dependent letter property comprises at least one of an inter-letter property based, at least in part, on an adjacent letter or a letter-combination property based on a letter-combination of which the letter is a part.