Originally video surveillance was done based on analog technology, closed circuit television (CCTV) and recording on video tapes. This was fine for recording what was going on, but it didn’t broadcast actual live information, so it wasn’t practical for monitoring stores, for instance, from a remote location. It simply provided what happened after the fact. The picture quality wasn’t great and it relied on human reliability as well. Someone had to remember to change the tapes regularly, etc.
Digital Revolutionized Video Surveillance
With the Internet revolution and the ever-increasing presence of Local Area Networks, technology took great strides in video surveillance in the 1990’s. Analog camera tubes were replaced with CCD (Charged Coupled Devices) and digital cameras became affordable for most consumers & businesses.
Digital Surveillance meant that video surveillance could:
• go live over the Internet or a closed network for surveillance
• provide clearer, crisper images that could be tracked and manipulated easily
• zoom in on images, track particular scenes and enhance features
A digital camera “views” the scene in front of it, broadcasts the video images as a digitized signal over a LAN line (Local Area Network/Ethernet) where it’s then transmitted to a computer or server. The server in turn manages all of this information.
Depending upon the software used to manage the digital images, it can record, display or retransmit the images to anywhere in the world. The software package can easily be upgraded to allow for analyzing data, selecting specific “flagged” items to watch for and a host of other functions, making it a truly customizable security tool.
True IP-based digital surveillance uses CCD cameras that use signal processing that send packetized video streams over the LAN through a Cat 5 cable rather than a coax cable network, utilizing greater bandwidth and standard TCP/IP communication.
IP-based digital surveillance also provides more intelligent data mining and information retrieval. If security is an issue, full digital surveillance also offers the added advantage of data encryption opportunities to protect against image tampering. (something not possible with analog recording)