Audio Forensics-Practices and Challenges

摘要

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 signal. The technique is optimized for data that has not been perceptually encoded post editing and is capable of detecting discontinuity points within a recording that are not discemable by auditory analysis.