The HD Doctor: specify this

26 Jul 10

By David Hammond

David Hammond of Sanyo answers your questions about Full HD camera technology. In this edition David makes the case for Full HD cameras to be the first option considered when designing and specifying a CCTV system or IP/network based surveillance system.

Just two years ago, the HD cameras produced by CCTV manufacturers were considered to be nothing more than very highly priced niche products that were ‘a solution looking for a problem’ rather than offering a genuine mainstream alternative and higher performance option to standard CCTV cameras.

Much has changed, and in the last year in particular the price performance ratio of Full HD cameras is now meeting customers’ expectations.

Whereas in the past the question might have been ‘why’ HD cameras, the question nowadays should be ‘why not’, and there are clear signs that end-users are looking for image quality from their CCTV systems which match what they can watch on their home HD TVs.

They certainly could ask the question as to why they should use CCTV cameras which capture less pixels per image than the cameras on their mobile phones, to protect their property, assets and create a safe environment for their staff.

Multi-camera job
A full HD image of 1920 x 1080 can, depending on the field of view, do the job of four to five standard cameras.

By this I mean that if you are looking to monitor a wide area, you will need to install a number of cameras to look at different sectors of the same view in order for those individual cameras to achieve the image quality and resolution of a single Full HD camera.

Depending on the project, this point alone makes the case for choosing Full HD cameras over standard CCTV cameras; but there are other benefits as well.

Recording at the highest resolution of four megapixels offers major advantages over standard CCTV cameras in respect of post incident analysis.

Zooming advantages
With high definition you can enlarge an image and zoom in on detail with a clarity that is just not achievable with a standard CCTV camera.

‘Face detection’ is a good example of the additional benefits offered by Full HD cameras. This function equips the camera to recognise that a face or a group of faces are present in an image. If so the camera optimises the focus, contrast and backlight compensation functionality of the camera so that a clear image of any face is achieved, regardless of whether the scene is high or low backlit.

Equally impressive is video analytics functionality built-into Full HD cameras which can be programmed to identify the behaviour of subjects.