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DelaySystem is a simple and cost-effective way to upgrade a standard
time-lapse VCR to offer pre-event recording. This advanced feature,
normally associated with costly digital recording systems, offers
the advantage of capturing the complete event of interest rather
than a second or two after the trigger.
Delaysystem operates by utilizing large banks of high-speed memory
to provide a 1 to 120 second video delay with a negligible loss in
quality. (custom delays are available) The system consists of a
small DC powered unit that is very simple to operate, ideal for
covert installations. DelaySystem also offers a number of
operational benefits. For example, in battery powered remote
surveillance applications, installing DelaySystem can significantly
improve battery life by storing video while a VCR is completely
powered-down. When a trigger is received, the VCR may be powered-up
and start recording well before the delay cycle is completed.
Delaysystem can also improve the performance of low-cost motion
detectors by allowing decision times to be increased, dramatically
reducing the number of false triggers.
Video DelaySystem Dimensions and Interfaces:

Video Delay
Specifications
Applications
Action Replay

DelaySystem video
delay line temporarily stores up to 2 minutes of video. It is
therefore possible to use the delay line to replay an event of
interest without the need to stop and rewind a video recorder.
For example, a CCTV operator can double-check if an offence has
taken place by switching to the delayed video, which will replay
the event a few seconds later. Installation is very
straightforward. Simply take the video out from the viewing
monitor and feed it into the DelaySystem unit. The output of the
DelaySystem video delay unit can then be viewed on a second
monitor or by connecting to the monitor’s “B” input, if
available.
Event Capture / Repeating Action Replay

With an external video switch and monitor, DelaySystem can be
used to capture
an event and constantly repeat it. With the switch in the normal
“view” position
the operator sees the live video. If an event of interest
occurs, the operator may switch over to the delayed version,
which will replay the event (of say 10 seconds
duration) and then constantly repeat the event as it is fed back
into the
DelaySystem.
(Note: The same video is being fed into the Delay Line each
time, and therefore
degradation occurs over a period of time. However, the system is
capable of at least 10 to 20 repeats of good quality video.)
Time-Lapse VCR Pre-Event Recording

DelaySystem can be used to upgrade a standard time-lapse VCR to
pre-event recording. This
is an advanced feature, which is normally associated with
digital hard-disk recorders rather than traditional VCRs.
A time-lapse VCR can normally be
set to record in real-time form either time-lapse or standby under the control of an
external alarm input. The major problem with this approach is that it takes time for the VCR to
change mode, which can result in
a vital loss of footage. By introducing a delay in the video feed
(and not the alarm input)
of the VCR, the change of mode takes place before the event,
resulting in pre-alarm recording.
Synchronizing Video & Audio Feeds

Digital video and audio compression and transmission systems can
introduce
differing amounts of delay to video and audio signals. “Lip-Sync”
requires video
and audio synchronization otherwise the viewer becomes distracted by
the lack
of coordination between the subject’s lips and voice. If the audio
is delayed more than the video,
DelaySystem can be used to synchronize the two feeds.
Allen
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