The West Galleria Shopping Center in Seoul, South Korea, features a control system that turns a building facade into one big TV screen.

To design a system based on nearly 4,330 pixels of light, each capable of over 16 million colors, is a wild idea. The real challenge, however, was not the concept, but rather to stay in control of it.

The RGB light source behind every glass disk decorating the façade of the Galleria West in Seoul is ultimately connected to a personal computer that runs a video file, such as a DVD or a QuickTime movie. The difference from other lighting installations-even the colorful ones-lies in the fact that the system accepts this video format as input and converts it to lighting control commands. It is the computer that works out how the video image is mapped onto the façade by assuming that every light source is a pixel in a large image. Using a video format gives creative freedom to the designer, who can craft his latest work in Adobe Premiere, or 3D Studio Max, or any other animation program. Even a handi-cam is applicable, because the Galleria's control system can accept and convert plain video footage into lighting commands.

But before the signals end up as regulated low-voltage power at the fixtures, they go through a chain of devices, each critical to the final result. The personal computer (or its backup machine, since the whole system is fully redundant) produces TCP/IP signals over ordinary ethernet CAT5 cable, similar to the network cable in your office. This signal is distributed to ethernet-to-DMX converters, each having their own IP address to create a stable, industry-strength platform that is based on the same network protocol as the World Wide Web.

The DMX-converters send the DMX-512 to the power supplies of the RGB fixtures. As each fixture needs three control channels to create the smooth colors that make up the Galleria design, only 170 fixtures can be driven with every DMX-512 line. Having nearly 4,330 fixtures installed, 32 DMX lines or 'universes' are needed to control the entire façade in total synchronicity.

The power supplies, which are mounted all over the façade, accept DMX-512 and output a regulated power that is specifically designed to drive LEDs. Each power supply drives three light fixtures, which is in alignment with the structural layout of the facade. rogier van der heide

For the full story on the Galleria West Shopping Center, click heredetails

project Galleria West, Seoul, South Korea

client Hanwha Stores, Seoul, South Korea

architect UN Studios, Amsterdam

lighting designer Arup Lighting, Amsterdam

photographers Design team, except where noted

manufacturers applications

CGE Glass Custom laminated glass discs

e:cue Control system

Xilver Custom-designed LED fixtures