ENF Discontinuity
Definition
A break in the continuity of the extracted ENF trace that is inconsistent with the reference database. Can indicate a deletion (missing segment), an insertion from another recording, or a splice from a different session or grid, each with a characteristic signature.
- Cause 1
- Deletion: a missing segment removed from the recording
- Cause 2
- Insertion: audio spliced in from another recording
- Cause 3
- Splice from a different session or a different power grid
- Diagnostic value
- Each cause leaves a distinct trace-continuity signature
Common questions
How does an examiner tell a deletion apart from an insertion in the ENF trace?+
A deletion shows as a clean jump in the trace where the phase or frequency value skips forward without the intervening seconds appearing anywhere in the reference database. An insertion instead shows a segment whose fluctuation pattern matches the database at a different, non-adjacent time window than the material around it.
Can a discontinuity occur without the recording being tampered with?+
Yes. A device pause, a recording restart, or a hardware glitch can also break trace continuity, so a discontinuity is treated as evidence of a break in the recording, not proof of deliberate editing, until other evidence corroborates intent.
Related terms
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