Embedded Network Video Recorders (NVRs)
over Windows-based NVRs Comparison
Video surveillance users who opt for an NVR using an embedded,
dedicated Linux operating system within a self-contained unit will benefit from
performance which is superior to that offered by a Windows-based NVR in terms
of ease of use, system stability and decoding capability.
Embedded NVRs are distinguished from WINDOWS-based NVRs
primarily on how they operate and the features they provide. The stand-alone
NVR comes in a single, compact enclosure. By contrast, a WINDOWS-based NVR is a
peripheral addition to a system involving a CPU, keyboard and monitor. In
confined locations, an embedded unit performs a similar if not wider range of
functions while occupying less space. Embedded NVRs have overcome their
perceived shortcomings in terms of storage capacity and types of storage medium
through use of devices including IP-SAN, eSATA, NAS (network-attached storage)
and Fire wire. Furthermore, embedded NVRs can support interfaces to other
surveillance devices which can be conveniently integrated with alarm systems
and access control systems as well as PTZ remote control systems.
Functions common to the two approaches
Some common functions between the two video recording solutions
in the surveillance market, it will be useful to list the core functions that
are common to both approaches. These include: recording; archiving; display;
playback; search on parameters such as date, timeline and event; camera
management; triggered recording on prescribed events and export to removable
media. NVRs are also usually expected to be able to handle VoIP packets. Once
digitalized video has been streamed, end-users expect to be able to treat it
like any other network data, viewing it locally, on LANs and remotely from web
browsers. They also expect to be able to exercise PTZ control over cameras
remotely, configure settings and even perform upgrades remotely.
Storage
Although NVRs have ample internal recording and storing space,
the PC-based systems offer as much as seven times more storage, when compared
to an NVR. This advantage is, however, addressed by NVRs, through the provision
for external storage options (USB storage devices, eSATA devices, Firewire
storage devices, NAS appliances, etc.)
Reliability
The precise architecture of the embedded NVR units makes them
less prone to crash. However, the WINDOWS methodology for NVRs is certainly
'open' in terms of the addition of external storage, installation of software
etc. The controls are embedded into the NVR; they are an integral part of the
panel rather than an adjunct, and the activity of operators can therefore be
more easily restricted to legitimate usage.
Stability
Unlike a WINDOWS-based unit which is likely to run a range of
Windows™ applications, an embedded NVR benefits from the stability that comes
with Linux code which is optimized to run only applications relevant to the
surveillance tasks required. An embedded operating system contains only the
software components necessary for the specific functions of the NVR, and the
unit will be supplied with optimum configurations straight from the factory
after rigorous testing.
Scalability
An NVR is designed to offer optimal performance for a set number
of cameras, and is normally less scalable than a WINDOWS -based system. This
makes the unit suitable for smaller systems where the number of cameras stays
within the limits of an NVR’s designed capacity.
Boot Time
The NVR runs an embedded operating system as compared to a WINDOWS
-based system, which needs to run an application under the Windows OS before it
begins recording. This means that the NVR will start faster as compared to the WINDOWS
-based system; which will take longer to load.
Complex decoding
Embedded NVRs consistently outperform WINDOWS-based solutions in
their ability not only to perform complex decoding but also to give the user
reliable video playback and preview. Currently, certain NVRs are among the few
units which can perform both local decoding and playback, with decoding of up
to 16 channels at 1080p being achievable. The processing demands made on a WINDOWS-based
solution to achieve comparable performance are far higher than those required
of an embedded device, and necessitate powerful, expensive CPUs.
Power consumption and manufacturing carbon footprint
Embedded technologies are helping the surveillance industry to
go green in marked contrast with the WINDOWS approach. The power consumption of
an embedded NVR is approximately 70W which is less than an incandescent light
bulb. By contrast, the likely power consumption of a WINDOWS capable of running
an NVR is approximately 200 watts and together with a large enterprise-grade
monitor, the total figure will be about 300 watts. For any end-user mindful of
their carbon footprint, these figures alone must do much to settle the debate.
Ease of Use
Embedded NVRs can have operating panels based on the very best
intuitive design principles. LED signals, digital inputs and outputs, push
buttons and dials can all be arranged in an ergonomic way. Sensible layout in a
panel approach rather than a screen-based GUI can replicate the ease of use
found in a WINDOWS but without the vulnerabilities described above.
ONVIF
Linux based Network Video Recorder for
multi-brand and ONVIF compliant multi-megapixel IP cameras and basic
automation.