1. A computer-implemented method of processing a visual query performed by a server system having one or more processors and memory storing one or more programs for execution by the one or more processors, the method comprising: at the server system: receiving from a client system distinct from the server system a visual query and information identifying a geographic location of the client system; performing optical character recognition (OCR) on the visual query to produce text recognition data representing textual characters, including a plurality of textual characters in a contiguous region of the visual query; scoring each textual character in the plurality of textual characters, including scoring each textual character in the plurality of textual characters in accordance with the geographic location of the client system, wherein the scoring of a respective textual character comprises generating a language-conditional character likelihood for the respective textual character indicating how likely the respective textual character and a set of characters that precede the respective textual character in a text segment concord with a language model selected in accordance with the geographic location of the client system; identifying, in accordance with the scoring, one or more high quality textual strings, each comprising a plurality of high quality textual characters from among the plurality of textual characters in the contiguous region of the visual query; retrieving a canonical document having the one or more high quality textual strings; and sending at least a portion of the canonical document to the client system.