However ‘High Definition’ is a video format not a description of the highest-quality image available.
The maximum HD camera resolution is 2.1 megapixels yet the current maximum megapixel camera resolution is 29 megapixels. Therefore HD cameras can be classed a megapixel but many megapixel cameras offer resolution well beyond that of HD.
Most HD cameras transmit video via ip (internet protocol). IP systems have many considerations beyond that of a conventional analogue CCTV system such as: choice of camera, type of compression, network construction and media, streaming, recording, viewing stations and remote-viewing facilities.
Although technically possible it is not wise to piggy-back on a company’s existing computer network. Many business owners assume that an ip-based system will sit on their existing network thus saving installation costs. However the bandwidth used with ip cameras can severely impinge the normal day-to-day running of a commercial computer network. This usually results in poor performance of both computer and CCTV systems.
The most successful ip-CCTV systems are constructed on a dedicated network. Systems can still be viewed over the internet or via smartphones and tablets but the internal traffic of high resolution images are not affected by everyday computer network traffic such as emails, web-browsing, server file access etc.
With super high-resolution cameras then it is often achievable to cover very large areas with just one static camera. The ability to digitally zoom into an image without pixilation means that megapixel CCTV can often be designed using fewer cameras than a conventional analogue system. However very-good scene illumination is critical with HD cameras. Poor lighting results not only in poor images but also an increase in file size, bandwidth use and disc space / recording.