The purpose of forensic voice comparison is to assist a court of law in deciding whether the voices on two (or more) recordings were produced by the same speaker or by different speakers. The known-speaker recording is often an existing recording in which the identity of the speaker is not disputed, but sometimes a recording is made specifically for the purpose of conducting a forensic-voice-comparison analysis. Historically and in present practice, several approaches have been used to extract information from voice recordings and different frameworks have been used to draw inferences from that information. A simple automatic voice-activity detector may be based solely on root-mean-square amplitude, and thus simply find louder parts of the recording.