Multiplexing
Definition
The practice of interleaving frames from multiple camera channels into a single recording file. Each channel gets a share of the total capacity, reducing the effective frame rate per camera.
- Definition
- Interleaving frames from multiple camera channels
- Effect
- Reduces effective frame rate per camera
- Context
- CCTV and DVR recording systems
- Forensic concern
- Affects timestamp and frame rate interpretation
Common questions
Why does multiplexing matter when timing an event from CCTV footage?+
Because each camera only receives a fraction of the recording capacity, the effective frame rate for any one channel can be far lower than the system's rated overall rate, so an analyst must confirm the per-camera rate before estimating time gaps between frames.
Can multiplexing cause a moving subject to appear to skip or jump?+
Yes, if a channel is only recording a few frames per second because bandwidth is shared across many cameras, fast motion between the sparse captured frames can look discontinuous, which is a recording artefact rather than evidence of tampering.
Related terms
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- NVR (Network Video Recorder)
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- Proprietary Player Extraction
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- Write Blocker
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