Monday, 5 October 2009

Digital Signage And Its Hidden Components.

When considering a digital signage project users normally focus on screen size and software packages, for the integrator however there is an important component that the user rarely considers, the distribution technology and platform.

This infrastructure transmits the digital video and audio from the server to the appropriate displays and is a key contributor to actual digital signage performance.

In addition, as the connecting components for all displays, the distribution technology can be a significant part of the project budget. That is why choosing the right distribution channel is vital to ensuring a successful digital signage installation.

The three options open for dynamic signage distribution are:

Data networks
Fibre optic cable
CAT5 cable

Each platform has its benefits and drawbacks as outlined below.

Data Network Platform.
A data network platform uses computer network infrastructure in order to transmit content in the form of compressed multi-media files (such as MPEG), from the management centre to the central server and from there to the computer connected to the display device. The display end computer decompresses the files, then displays them on the displays.

Benefit – This is a god cost effective method, providing there is an existing infrastructure and it can cope with the demand.

Drawback – requires a Central Processing Unit for each display used, as well as needing a sound, reliable infrastructure that is already in place.

Fibre Optic Cable Platform.
Fibre is a transmission medium favoured for applications that need high band width, long distances and complete immunity form electrical interference. Making it ideal for dynamic signs, which requires high resolution and transmission over long distances. Unlike network platforms fibre optic cable does not require CPU’s or special software at the display end. All that is required is a transmitter and receiver unit for each display.

Fibre options come in two forms: either single mode or multimode fibre. Single mode fibre provides a higher transmission rate and up to 5o times the distance than multimode, but it costs more. In general, the difference between the different types of fibre should be the result of a simple cost benefit evaluation: the distance and level of resolution or performance required versus the acceptable investment in distribution technology.

Benefit – Fibre optic provides network independent performance without downtime or transmission lags. It can transfer media over 40Kg and more.

Drawback - However fibre optic is a point-to-point technology, in other words a pure fibre optic cable solution will not allow multiple displays to receive output from a single video source. This is an issue when installing in malls and airports.

For outdoor installations, a good quality LCD enclosure and plasma enclosure are equipped with fibre and Cat5 cable access.