FORENSIC AUDIO AUTHENTICATION
AND AUDIO ANALYSIS
WHAT IS AUDIO AUTHENTICATION?
Audio authentication is a form of forensic science used to determine if a file presents accurate, unaltered information. According to the Scientific Working Group on Digital Evidence (SWGDE), the recording should be consistent with how it was supposedly created.
HOW TO AUTHENTICATE AN AUDIO RECORDING
Audio authentication includes a series of steps:
When we first receive an audio file, our audio authentication experts will review it closely. This initial listen involves noting audio behaviors such as background noises and voices. If we notice any unusual sounds or activity, we know what to pay attention to during processing.
The metadata — the information embedded in the file — can make critical statements about an audio clip's authenticity. Notably, metadata will reveal the use of any third-party recording and editing software, such as Adobe Audition. This information doesn't confirm editing, but it can be a strong indicator.
After analyzing the metadata, we'll examine the audio itself to detect any edited audio. Tampering may involve removing sounds or even rearranging sentence structures to change the value of the information.
CREATING AN EXEMPLAR RECORDING
The final stage of integrity testing involves creating another recording with the same method used to create the evidence. Our audio experts will try to recreate recording conditions as closely as possible to the original file. From here, we can compare hexadecimal (HEX) information and metadata to see if they match.
TESTING TIME AND FREQUENCY DOMAIN
Digital audio authenticity also relies on time characteristics and sound frequencies. An audio authentication analysis may involve using an electronic measurement test to look at the start signature or sampling rates. Experts will also listen for frequency shifts in background noise, voices and other notable sounds on the recording.
WORK WITH PRIMEAU FORENSICS FOR AUDIO AUTHENTICATION SERVICES
With 35 years of industry experience, Primeau Forensics has the resources for proper scientific audio authentication. Our experts are trained under law enforcement to apply their skills to court cases, and we have experience testifying in court. Our services offer an unbiased examination of audio files for use in legal matters.
Contact us or call us at (800) 647-4281 to ask about our forensic services.