1. A method for generating a full-length fingerprint of a video, the method executed by at least one computer system, the method comprising: accessing a plurality of subfingerprints for the video, wherein each subfingerprint encodes features of a corresponding segment of the video; generating a plurality of subhistograms, wherein each subhistogram encodes a frequency of a subfingerprint feature for a subset of the plurality of subfingerprints; concatenating the plurality of subhistograms to generate a histogram, wherein the histogram encodes a frequency of the subfingerprint feature for the plurality of subfingerprints; generating the full-length video fingerprint based on the histogram; and storing the full-length video fingerprint to memory.