19. A method performed by one or more computer devices, the method comprising: sampling, by at least one of the one or more computer devices, a document to obtain a plurality of sampled blocks; generating, by at least one of the one or more computer devices, a set of checksum values from the plurality of sampled blocks, where each checksum value, in the set of checksum values, identifies a respective one of a plurality of bits of a fingerprint for the document; and generating, by at least one of the one or more computer devices, the fingerprint, for the document, by flipping each bit, of the plurality of bits of the fingerprint, a quantity of times based on a quantity of checksum values, in the set of checksum values, that identify the bit.
19. A method performed by one or more computer devices, the method comprising: sampling, by at least one of the one or more computer devices, a document to obtain a plurality of sampled blocks; generating, by at least one of the one or more computer devices, a set of checksum values from the plurality of sampled blocks, where each checksum value, in the set of checksum values, identifies a respective one of a plurality of bits of a fingerprint for the document; and generating, by at least one of the one or more computer devices, the fingerprint, for the document, by flipping each bit, of the plurality of bits of the fingerprint, a quantity of times based on a quantity of checksum values, in the set of checksum values, that identify the bit. 21. The method of claim 19 , where the set of checksum values is a subset of checksum values generated for the document, and where the method further comprises: selecting the subset of checksum values as a particular number of smallest, unique checksum values of the checksum values generated for the document.