Detecting Butt-Spliced Edits in Forensic Digital Audio Recordings

Detecting butt-spliced edits in forensic digital audio recordings Alan Cooper, Metropolitan Police, United Kingdom Digital audio recording forgeries are often created using simple editing techniques such as ‘butt splicing’. Butt-splicing may leave discontinuities in the audio waveform that may or may not be audible. Detection of butt-spliced edits will be discussed and a new method to detect edits made in this manner will be proposed. The process operates in the time domain and is based on high pass filtering the audio data and modeling a discontinuity at higher frequencies where the ratio of discontinuity energy to acoustic signal energy level is improved. The model is then used as a template to search for potential edits in the filtered audio data. The technique is optimized for noncompressed audio and is capable of detecting discontinuity points within a recording that are not discernable by auditory analysis.