Mulling over whether to opt for digital IP cameras for your CCTV or analogue HD? Well, it’s important to fully understand how the technologies work. The differences in both camera technologies and method of video transmission can be critical to planning a CCTV solution that suits your requirements (and meets your expectations). It should be noted that as installers of both IP and analogue CCTV cameras, we have no bias towards one or t’other, here at Aerial Services. It’s a case of horses for course!
Both technologies have their place, and hopefully this article will help you get an idea of their key differences. If you have any questions that still need answering, feel free to give us a call for some (free) impartial advice.
Analogue HD
HD Analogue systems are capable of delivering up to 1080p HD video (the same quality most people expect from their HD TVs these days), something which traditional analogue systems wouldn’t have been able to dream of, and something which counters any argument that analogue necessarily means ‘old hat’. 1080P / 2.1 megapixel HD cameras capture over 4 times the resolution of the most powerful traditional analogue cameras, allowing users to zoom in quite effectively to view a level of detail that is more than adequate for many security applications.
Like traditional Analogue systems, HD Analogue systems are relatively simple to install and maintain, not requiring the networking equipment and level of knowledge associated with the latest IP solutions. And because HD Analogue systems function ‘off network’, they don’t interfere with other network-related activities, or consume bandwidth which may be needed for other purposes/devices.
With traditional analogue CCTV systems, cameras capture an analogue video signal and transfer that signal via coax cable to the Digital Video Recorder (DVR). The DVR converts the analogue signal to digital, compresses it, then transfers it to a hard drive for easy retrieval later. The DVR is designed to handle tasks such as scheduling, motion detection and digital zoom. Monitors connected to the DVR allow for viewing, or it can be set up so that footage can be published over an internal network for viewing via computer or smart device. The DVR can also be set up to broadcast over the web (with password security and other features). When broadcasting over the web, the video for all cameras is consolidated and transmitted as one stream (one IP address). Therefore, it is very efficient.
Digital IP
Few experts would disagree that the primary benefits of IP security cameras are resolution and image quality. These two attributes offer images with detail of forensic standard, and digital zoom functionality with lossless image clarity. This all means more effective identification, and provides greater accuracy for automated analysis, alarms and notifications.
With IP CCTV, each network camera actually captures an analogue image but this is converted to digital immediately whilst still inside the camera. In fact, all digital processing happens in the camera, from compression to motion detection. The digital video stream is then sent over the local area network (LAN) using Ethernet (CAT5 or CAT6) cable.
Power is supplied to the cameras through the ethernet cable via Power-Over-Ethernet (POE) adapters which are built into the cameras and at the (POE enabled) switch. The ethernet cable for each camera is plugged into the switch which feeds into the network hub. As you’d expect, some setting up is required for each network camera to configure them for the appropriate IP address etc.
A Network Video Recorder (NVR) fulfils the same role as the analogue system’s DVR i.e. it captures each camera’s signal, compresses, and records it. The NVR combines the video streams from the cameras and handles the broadcast over the LAN and internet for local and remote viewing. The key difference is that the video feeds are digital rather than analogue and much higher resolution. Software built into the NVR typically provides features such as intelligent search and zoom, etc.
We hope you’ve found this information useful. If you’re seeking or considering CCTV installation in the Northampton, Kettering, Wellingborough or Market Harborough areas, give us a call today to discuss your operations.