DVR (Digital Video Recorder)
Definition
A recorder that accepts analogue camera signals, digitises them internally, compresses the result using a proprietary or standard codec, and writes to an internal hard drive. Common in legacy CCTV installations.
- Full form
- Digital Video Recorder
- Input
- Analogue camera signals
- Compression
- Proprietary or standard codec
- Use context
- Legacy CCTV installations
Common questions
Why does codec choice matter when a DVR's footage is used as evidence?+
A proprietary codec often requires the manufacturer's own playback software or a specific export utility to view or convert the footage correctly, and using an incompatible player can distort timestamps or introduce visible artefacts that undermine the footage's evidential reliability.
How can an examiner confirm DVR footage has not been altered after export?+
By hashing the exported file immediately after extraction and documenting the export method and software version used, then comparing that hash at every later handling step, consistent with standard digital evidence chain-of-custody practice.
Related terms
- Chain of Custody
- The documented chronological record of who collected, handled, transferred, and examined a piece of evidence. For digital evidence, chain of custody includes...
- Multiplexing
- The practice of interleaving frames from multiple camera channels into a single recording file. Each channel gets a share of the total...
- NVR (Network Video Recorder)
- A recorder that receives pre-compressed IP-camera streams over a LAN and stores them, typically in a structured folder on an internal drive....
- Proprietary Player Extraction
- An acquisition method in which the examiner uses the vendor's own playback software to export footage from a running device. Fast and...
- Write Blocker
- A hardware or software device interposed between a digital storage medium and the forensic workstation that prevents any write commands from reaching...