As in our TV systems, HD video in CCTV provides us with high quality, high resolution images. However in CCTV, HD provides us with many other benefits that enhance the surveillance we can provide in any particular application.
The CCTV industry is now taking advantage of the developments of High-definition video systems that we are now familiar with on our home TV screens. As in our TV systems, HD video in CCTV provides us with high quality, high resolution images. However in CCTV, HD provides us with many other benefits that enhance the surveillance we can provide in any particular application.
The clearest advantage of HD video is that cameras can provide very precise images in any live monitoring application, whether this is the facial recognition of people or vehicle registration plate numbers.
Also, in a Live Monitoring situation, the most effective CCTV systems are what we describe as Event Driven. This means the camera can detect something unusual or unexpected in its field of view. This can be movement in a particular area, or an item that has been left in a location for an unexpected length of times. This facility is often known a Video Analytics or intelligent Video. In essence the camera learns the normal image scene it is monitoring and creates an Alarm Event when this changes. HD enhances the performance of these faculties due to the quality of the images being analyzed.
HD systems also improve the effectiveness of recorded imaging. Primarily this is due to the fact that the information can be digitally zoomed without the loss of quality. This was traditionally known as Pixilation. The higher the quality of the camera the greater the digital zoom available.
High-definition video or HD video refers to any video system of higher than, and most commonly involves display resolutions of 1,280×720 pixels (720p) or 1,920×1,080 pixels (1080i/1080p). However much greater resolutions are now available with the introduction of megapixel cameras. For example, a camera that makes a 2048 × 1536 pixel image typically uses a few extra rows and columns of sensor elements and is commonly said to have “3.2 megapixels. We can offer a whole range of megapixel cameras from 5, 10, 20 or even 200 megapixels if required.
Video Analytics Or Intelligent Video:
The most effective CCTV systems are what we describe as Event Driven. This means the camera can detect something unusual or unexpected in its field of view. This can be movement in a particular area, or an item that has been left in a location for an unexpected length of times. In essence the camera learns the normal image scene it is monitoring and creates an Alarm or Event when this changes.
A whole range of monitoring parameters are available in Video Analytic Systems that can be used in many different applications. Some examples are Virtual Trip wires which can create and alarm and associated events when a person passes over a set location in a protected premises. Object Monitoring can alert the Operator when a person, vehicle or object has dwelled in a location longer than expected. Video Analytics are not only being used for Security Surveillance. Other common applications are in Retail Environments when they can provide invaluable marketing information on shoppers activity and movements including Head Counting. Traditionally this type of information has been collated manually.
Another example of Video Analytics is for Health and Safety applications when the CCTV scheme can be utilised to monitor any potentially dangerous or hazardous areas within a protected premises. The use of CCTV for other purposes for clients provides great additional benefits, which often means the cost of the installation can be shared among a number of departments or divisions with an organization.
IP or Networked Systems
Digital Systems are now available that utilise computer networks and digital video transmission techniques. Instead of being hardwired to a central control point, IP cameras are linked to the control and/or storage device via a computer Data Network. This can be a Digital Video Recorder (DVR), Network Video Recorder (NVR), Network Attached Storage (NAS) or simply a PC installed with the appropriate Video Viewing Software. Very often a clients existing Data Network can be utilised for the CCTV scheme reducing traditional cabling costs. A number of the key advantages of IP Systems are highlighted below:-
- Video Quality:
IP camera development means we now have High Definition broadcast quality cameras available within the CCTV industry. This means both live and recorded images of the highest we can be provided in any particular application. A range of cameras can be offered from 5 to 200 megapixel capability.
The cameras can be viewed from any authorised PC on the Network. This can be on or off site.
IP Camera technology means the devices are far more versatile than analogue units, offering such facilities as Video Analytics, and recording capabilities within the camera itself.
(Power over Ethernet) – IP cameras can be powered from the Network Data switch removing the need for the installation of a separate mains supply and battery backup unit.
- Cost Effective:
Although initially more expensive than the cost of analogue cameras prices have reduced as the technology is being more widely implemented. Any price comparison with Analogue systems must take into account the savings in the cost of cabling if the existing Data Network is being utilised and the use of POE devices as described earlier.