Service
Audio forensics
What is examined
- Container and codec structure, metadata and encoding history
- Continuity of the signal, background noise and mains hum
- Indications of cuts, splices or re-encoding
- Speech intelligibility in the presence of noise
How the examination is carried out
- 1.Analysis of waveform, spectrogram and file structure
- 2.Comparison of the recording with the claimed recording device where available
- 3.Careful, documented filtering; every processing step is recorded
- 4.Separation between measurable finding and interpretation
Technical limits
These limits are stated before the instruction, not afterwards.
- Speaker identification is not offered.
- Content that was never recorded cannot be restored by filtering.
- Re-encoding by messengers removes many traces of the original.
- The absence of editing traces is not proof of authenticity.
FREQUENTLY ASKED QUESTIONS
Audio forensics: frequently asked questions
Cuts and re-encoding often leave measurable traces. Where such traces are found, they are documented; where none are found, that is stated without being presented as proof of authenticity.
Analysis takes place on the secured working copy in the permanent examination rooms at the registered office in Krefeld, Germany. Devices are handed over in person or sent by insured carrier; by prior arrangement, processing in Munich is also possible. Where the technical conditions allow it, the acquisition itself can also be carried out at the client’s premises or at the location of the item; unavoidable changes to a running system are documented with reasons.
Whether an expert report is used in proceedings, and what evidential value it carries, is decided by the competent court or investigating authority. Our examinations are documented so that third parties can review them: recorded handover, cryptographic hashes, described methods and a clear separation between technical finding and assessment. A binding assurance of later admissibility cannot be given.
Next step
Discuss your case
Describe the situation briefly. We will say what can realistically be established, and what cannot.