1. A method, comprising: capturing an image of a document using a camera of a mobile device; classifying the image as an image of a financial document, the classifying further comprising: generating a first representation of the image, the first representation being characterized by a reduced resolution; generating a first feature vector based on the first representation; comparing the first feature vector to a plurality of reference feature matrices; and classifying an object depicted in the image as a member of a particular object class based at least in part on the comparing; determine one or more object features of the object based at least in part on the particular object class; performing optical character recognition (OCR) on the image of the financial document; extracting an identifier of the financial document from the image based at least in part on the OCR; associating the image of the financial document with metadata descriptive of one or more of the financial document and financial information relating to the financial document; and storing the image of the financial document and the associated metadata to a memory of the mobile device.
18. The method as recited in claim 1 , further comprising detecting an attempt to initiate a financial transaction using the financial document, and determining whether the financial document is an eligible form of payment for the financial transaction in response to detecting the attempt to initiate the financial transaction.