You need to be very careful about what you’re looking at and what the various terms signify while searching for an IP-based video surveillance system. There is no genuine consensus on what the term “IP-based” or related ones such as “networked” or “web-based” means; as a result, how IP-based video surveillance actually works is open to interpretation by some video surveillance and security salespeople.
Historically, CCTV (closed circuit television) and videotape recording were the foundations of video surveillance. While this worked well for keeping a record of events, it was not suitable for real-time monitoring of, say, a retail store from afar because it did not transmit data in real-time.
What transpired after the fact was all that was disclosed. Changing the tapes on a regular basis, etc. required human reliability, hence the picture quality wasn’t fantastic.
Video surveillance has undergone a digital revolution.
Technology in video surveillance advanced greatly in the 1990s, thanks in large part to the rise of the Internet and the proliferation of Local Area Networks.
The introduction of CCD (Charged Coupled Devices) technology and the subsequent drop in the price of digital cameras made them accessible to the masses.
This synergy meant that not only could video surveillance be streamed in real time over the Internet or a private network for surveillance, but it could also give sharper, more detailed images that could be followed and altered with greater ease. The ability to digitally zoom in on footage, track certain scenes, and improve features has greatly aided law enforcement.
How IP-based monitoring systems work
A digital camera “sees” what’s in front of it, converts its video feed into an electronic signal, and sends it across a LAN line (Local Area Network) to a receiving computer or server. The server then handles all of this data management. Digital photographs can be stored, viewed, or retransmitted to any location on Earth, depending on the software used to manage them.
The program is easily upgradeable, so it can be used for data analysis, and you can choose which “flagged” items to keep an eye on, among other things, making it a highly adaptable security tool.
CCD cameras with signal processing transmit packetized video streams over the LAN using Cat 5 cable, rather than a coax cable network, for true IP-based digital surveillance, which makes use of the increased capacity and standardized TCP/IP communication.
Additionally, it allows for smarter data mining and retrieval. Full digital surveillance has the advantage of data encryption to prevent image tampering, which is impossible with analog recording if security is a concern.
D-Link and Linksys are only two of the firms that have produced fully digital cameras with in-built web servers that can be used independently of a computer. The signal is sent straight to the receiver, where it can be recorded or played back.
In the home stretch…
The “Goldilocks” approach to video surveillance is to use an advanced system like a Digital Video Recorder (DVR). A DVR system is not entirely IP-based, but it is an intermediate step on the road to more sophisticated IP technology. In reality, a DVR system is similar to an older CCTV analog system in terms of cameras and wiring, but the data storage devices, which were previously VCRs, have been upgraded to DVRs. Since the data originated in an analog format, the quality of the collected photos does not change when it is converted to digital for storage on hard disks.
Many manufacturers classify a system as digital because of the DVR storage system, even if the camera recording the images is still analog, so it’s important to clarify which is the case when looking for a system.
Taking it to the limit
When upgrading from an analog system, some users may opt for a hybrid CCTV/DVR system as the next logical step in practical video surveillance advancement. However, IP-based video surveillance is rarely considered in the transition to this technology.
By tack[ing] on relatively modern technology(hard disk, digital storage) to old technology(analog video via coaxial transmission lines), CCTV/DVR surveillance just delays the inevitable. You have postponed the inevitable by not moving on to anything new.
IP-based video surveillance has many benefits.
Making the switch to IP-only technology offers the greatest financial and safety returns. While it is possible to do digital surveillance via a local area network, it makes more sense to broadcast surveillance over TCP/IP in order to remotely monitor several places and to remotely record data into backup servers and hard drives for long-term storage.
With IP-based video surveillance, the location of the camera is not as restrictive, since it may be linked to any network or wireless adapter. Digital picture quality is only available when the camera is within 10 feet of the computer, which is the case with the majority of PC-attached video cameras.
IP-based video systems are simple to install and highly reliable after they have been given an IP address. This cutting-edge equipment can be improved upon in the future. IP-based video surveillance systems are here to stay, and as the industry evolves, your needs won’t exceed them. In contrast to prior CCTV+DVR hybrids, which will eventually reach a technological dead end, this system may be expanded and upgraded indefinitely.
Analog vs. IP-based Surveillance Cameras:
Analog vs. IP-based video surveillance systems are fundamentally different, and it may help to compare and contrast how they function.
Surveillance cameras, either analog or CCTV+DVR
A VCR-like interface makes it simple to use.
Because of the frequency with which cassettes must be changed and rewound, human error frequently compromises efficiency.
o Low-resolution images
o Backup tapes degrade with use.
Live video streaming is impractical, so forget about it.
Low-quality analog recordings that are difficult to find and keep tabs on are a drawback of this method.
o DVR installations must be completed in ‘blocks’ of 16 channels.
IP-based surveillance cameras
IP-based recording allows for instantaneous image transmission anywhere in the world and allows for the remote monitoring of several cameras simultaneously.
There will be no deterioration in sound quality by playing the recording over and over.
o The quality of digital images is far higher than that of analog.
IP-based recording may be moved across many different media types and has a high compression ratio for convenient storage.
It is possible to encrypt digital photos for privacy reasons.
· Software packages and Internet-based telecommunications allow for cheap updates and expansions.
o Frame rates that can be changed
o Internet or a wireless connection can be used for distant or collaborative viewing.
IP video compression standards are implemented.
IP security cameras can be added singly or in clusters, depending on your situation.
Knowing how IP-based video surveillance functions will help you make an informed decision about adding or upgrading video monitoring at your business or home. It may be more expensive in the short term, but in the long run, it is an apparent investment in higher quality and flexibility, making it the future of video surveillance.
This article on “How IP-based Video Surveillance Works” was reprinted from the author’s site with their express permission.
All original content by Evaluseek Publishing, 2004-2005.
Author Lucy P. Roberts has made a name for herself in the freelance writing industry by sharing her expertise on the issue of digital video surveillance [http://www.video-surveillance-guide.com/]. Her many writings cover a wide range of topics, from how to save money and time while shopping for video security solutions to in-depth analyses of specific pieces of equipment. Visit Video-Surveillance-Guide.com now to learn all there is to know about infrared cameras [http://www.video-surveillance-guide.com/infrared-camera.htm] and night vision security cameras [http://www.video-surveillance-guide.com/night-vision-security-camera.htm]!