The present invention relates generally to processing audio and video data. One claim recites a method of accessing content stored in a remote database. The method includes: receiving video or audio data; decoding an auxiliary machine-readable code from the video or audio data; deriving a fingerprint, which fingerprint is separate from the machine-readable code, from the video or audio data itself; providing user characteristics or an index to user characteristics; and by using the machine-readable code, fingerprint and user characteristics or information obtained with the index to user characteristics, accessing the content stored in the remote database. Of course, additional combinations and claims are provided as well.