Pump it up!: Laservision Digital Data Pump II

It seems very likely that nobody ever just sat down and decided to develop a show control system from scratch. Most show controllers appear to have grown out of the need to coordinate some existing specialist equipment with other elements of a production.

Some systems evolved out of the need to bring lighting — and later, motion automation and effects — under the control of a sophisticated audio replay and routing device. Video server systems have been extended to become show controllers by adding facilities to control lighting, audio matrices, and scenery automation. Other systems have evolved out of the need to integrate the control of lighting, sound, and special effects, with industrial process controllers that were adapted to drive automated scenery.

The original Digital Data Pump Series I (DDP) grew out of Laservision's need to coordinate lasers and image projection with sound, lighting, water, fire, and pyrotechnics. Laservision has a long history in the business of laser shows, having been early innovators in the technology of programming and controlling laser heads for spectacles throughout the Asia-Pacific region. The original Digital Data Pump that came onto the market about five years ago was, essentially, a data capture and replay system. Based around the Alesis ADAT Optical Digital standard, the system recorded digital data directly, while using a pulse width modulated encoding system to digitize and store analog data such as laser head positioning and audio.

The new Digital Data Pump Series II lies at the heart of a substantially more sophisticated show control system. The DDP II and its associated peripherals can author, record, edit, and replay eight channels of 24-bit audio, five universes of DMX, MIDI, SMPTE timecode, multiple formats of laser scanner and color control protocols, dry switch closures, full duplex RS-422, full duplex RS-485, VGA video, S-Video, and specialized serial data interfaces for Aqua-Screens, pyrotechnics, and Liquid Logic fountain systems.

Although DDP II had been under development for a couple of years, it was the selection of 18 units as the control system for Symphony of Light, the nightly son et lumiere in Hong Kong Harbor, that really pushed up the pace for completion (see “City of Nightlights,” LD, April 2004, p. 72). Premiering for the 2004 Chinese New Year, Symphony of Light is a 20-minute music-synchronized spectacle, featuring 18 of Hong Kong's most prominent harbor-side buildings. Together with approximately 8,000 channels of architectural and decorative feature lighting on the buildings, the performance incorporates over 40 roof-mounted color-changing search lights and two 40W Stella-Ray YAG laser scanners. In addition, for some performances each week, and for special celebrations, synchronized pyrotechnics are launched from the rooftops of ten of the buildings.

In keeping with the contemporary practice in equipment development, the engineers at Laservision have avoided reinventing as many wheels as possible. The Digital Data Pump is based around a standard PC-104 single-board industrial computer with a Pentium 4 CPU at its heart and FPGAs (Field Programmable Gate Arrays) to handle the data input and output. The DDP II's operating system is based on the stripped-down industrial version of Windows XP, and the built-in touchscreen panel and data transfer drives are based on standard PC components. The stylish split-level front panel and the decorative blue LEDs that glow behind it are reminiscent of the contemporary geek practice of PC case-modding.

Data outputs from the DDP II system are available locally on the rear panel of the DDP unit in either of two layouts or from a variety of remote output boxes that daisy-chain off the fiber optic data ports. All DDP IIs have outputs for stereo audio, SMPTE timecode, composite and S-Video, MIDI, switch closures, pyrotechnics and special effects serial data, laser control over optical fiber, and audio over fiber. The expanded version of the DDP II additionally includes outputs for DMX512 over fiber, four universes of DMX512 over copper, and inputs from up to four DMX512 universes for recording. For reasons that are completely unapparent, all DMX data outputs in the DDP II system are via non-standard combo-style XLR3/6.5mm jack connectors.

Fiber-linked decoder modules include special purpose units for laser control, audio, and DMX512. The laser decoder has outputs for several proprietary and standard laser control protocols, SMPTE timecode, a single DMX512 universe, and control outputs for Liquid Logic fountain systems and Aqua-Screen water projection systems. The audio decoder's output can be configured as either eight full bandwidth channels or as 5.1 channel surround. The DMX decoder module has DMX512 input in addition to its ten optically isolated DMX512 outputs. The DMX512 data can be routed from either the local input socket or any of the four fiber-borne DMX512 universes to any output socket. This allows the decoder unit to also function as a programmable optically isolated splitter and distribution box.

While the touchscreen display on the DDP II's front panel allows for complete system configuration, diagnostics, data input, show replay, and system monitoring, the detailed sequencing, authoring, and show configuration is handled on a separate computer workstation running Laservision's Media-Manager software.

Media-Manager is the key element that differentiates the DDP II system from its forebears, as it adds the possibility of creating and manipulating the elements of a production, rather than simply scheduling and replaying the content. It consists of a large and complex set of tools for creating and editing a range of media types, placing each element on the replay timeline to compose the performance and setting up the trigger events for each element in the performance.

Much work has already been undertaken on this complex software suite, but at the moment, some elements are missing, and several are lacking in functionality, possibly because they were not critical for the debut project in Hong Kong. As you would probably expect from a company with deep roots in laser technology and production, the laser imaging and manipulation tools appear to be very useful and substantially complete. There are some excellent preview and editing features for laser imaging which, if carried over into the processing of other mediums, could make Media-Manager a joy to use.

The DMX tools are a whole different matter. Together with many of the interface elements of DDP II and Media-Manager, the DMX editor interface looks quite stylish, in a sort of science fiction kind of way. However, the patch table and level editors are very primitive and probably only capable of handling the simplest of production elements, such as show presets and house lighting. Also, the promised DMX editor that will allow adjustments to be made to the recorded DMX stream has, as yet, failed to make an appearance.

The very cute preview tool that displays bar graphs of channel levels as your cursor moves along the lighting timeline is great (up to a maximum of 24 channels, perhaps), but would be meaningless for larger systems. As the Symphony of Light for Hong Kong was created on a Hog PC, and the DMX512 streams were simply captured and recorded by the DDP II, this aspect of Media-Manager is hopefully already undergoing further work from the development team.

The trigger selection and emergency shutdown sections of the software are sophisticated and complete, as these were critical to the Hong Kong installation. Despite this, the user interface for these screens feels like something you would see being played on a game console. Overall, there is a feeling to the Media-Manager/DDP II interface that Laservision may be taking their image as hi-tech company too seriously. We can only hope that the satin finished, illuminated look of the user interface has not taken valuable development effort away from the functional elements of the software.

Regardless of the interface screens, DDP II replay sequences can be initiated by an array of triggers that includes the local touchscreen, SMPTE timecode, MIDI, time of day, serial data, contact closure, DMX512, keyboard press, infrared signals, and commands sent by Internet or local area network.

In the case of the 18 DDP IIs deployed at 16 separate sites around Hong Kong Harbor, each DDP II triggers at precisely the same time of day, rather than risking errors due to Internet latency, packet loss, or a lost connection. To ensure that there is time synchronization between DDP IIs, each one utilizes the built-in facility to regularly realign its internal clock with one of the reference atomic clocks available via the Internet.

The DDP II communicates with the outside world via several TCP/IP based services. Each DDP II has an internal web server that allows remote configuration and operation. Its internal clock is updated via SNTP, while data uploading and downloading is possible via Secure FTP. The DDP II communicates with Media-Manager software on remote computers and with other DDP IIs using MCP, Laservision's own Media Control Protocol. A TCP-based protocol, MCP was developed for the express purpose of remote configuration, control, monitoring, triggering, and data capture on the DDP family of devices.

As all of these protocols are Internet routable, DDP IIs can be configured, controlled, monitored, and loaded with show data from any point on the Internet. The health and welfare of the DDP IIs on the Hong Kong Harbor project is monitored from Laservision's facility in Dural near Sydney, Australia, although the actual show scheduling is performed locally in Hong Kong.

The Digital Data Pump, now in its second and more powerful, flexible incarnation, shows substantial promise as a show control system for a wide range of applications. The hardware seems to be ready for the task, but further work needs to be done to some sections of the authoring software before the system can realize its full potential. I look forward to seeing how far the completed system can push the boundaries of show control for spectacular events.