Audio, acoustics, voice and video evidence are common in civil and criminal litigation throughout all state and Federal courts. Often such evidence is extracted from a computer or mobile device. All parties must at least be generally familiar with what can (and cannot) be done forensically and legally with such evidence: Content-based (and non-content based) Authenticity analyses forensically determine if the audio or video evidence is legally trustworthy (admissible), or whether it has been tampered or fabricated in any way (inadmissible). Digital signal processing (enhancement) makes the audio more audible/intelligible, or the video clearer. Photogrammetry allows determination of heights of suspects, etc. Aural-acoustic-spectrography is the forensic comparison of 2 voice samples (“known” vis-a-vis “unknown”) based on scientific principles well established in the speech and hearing sciences to determine the identity of a speaker. Learn generally what can and cannot be done in content-based forensic analyses of audio and video evidence, whether you're the proponent or opponent of the evidence.