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Recording
Most video surveillance environments require recording capability either to meet regulatory
requirements or to facilitate the investigation of events that have occurred.
Many traditional installations that relied on video cassette recorders (VCRs) now record events on
hard disks instead of VHS tapes. VCR recording systems are cumbersome and can make timely
retrieving of video difficult. Other drawbacks include:
●
VCRs typically are dedicated to provide only recording or playback. To view video during an
investigation, separate record and playback devices are required.
●
Device failures can go undetected for a long time. VCR or DVR technology usually does not
have device monitoring capabilities that notify an operator when a device fails. In contrast,
network-based recording provides management features to immediately send alerts when a
failure occurs.
●
To review recorded video from a remote location, tapes must be sent to the investigation
center or an officer must visit the remote facility. In a network-based environment, video
streams can be transmitted immediately to any network location for review.
With the declining availability of VCRs and to address recording limitations, other technologies
have emerged to enhance video surveillance recording. For the most part, DVR are stand-alone
set-top boxes with video inputs and basic recording software.
Solutions that are based on digital video recorders (DVRs) address some limitations of VCRs,
however, they do not provide the scalability and flexibility that an IP-network-based system solution
can provide such as integration with other business systems, greater access to video, and the use
of video analytics for safety, customer satisfaction, and operator productivity.
While tape-free DVR recording provides an upgrade in functionality over traditional VCRs, the
technology still exposes limitations, such as:
●
To view recorded events, a PC-based system typically is required, which prevents an
operator from using a familiar CCTV keyboard interface.
●
The cable infrastructure is centralized and typically relies on the same cable infrastructure
that was used to support a VCR installation.
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Only a few channels are recorded per device.
Design Guide
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