When you want to present digital content — most likely moving video, but it could be or include static images and text — in a way that’s bigger than the largest flat-panel display (currently up in the 90-to-108-inch diagonal range, excluding the hyperexpensive even bigger ones), the answer is a “video wall.”
Historically, there were four ways to do a video wall:
- Front projection (like in a movie theater), which required a dark room and nobody standing in the way.
- Rear projection, also requiring a darkish room and enough space in back for the projector.
- LEDs, like the “Jumbotrons” used in sports arenas and outdoor billboards — which assume viewers will be several tens of yards or more away.
- Stacks and rows of computer displays.
However, none of these were a good match for close viewing, bright rooms or complex, dynamic content.
Today, video walls that can address these requirements are being created using flat-panel displays. (However, front/rear projection is still in use, including for modular display “building blocks,” or along with flat panels in hybrid installations.)
Saint Louis University, in St. Louis, Missouri, for example, currently has several video walls, according to Craig Williams, manager, Multi-Media Services at the University. “We have two 2 x 2’s in regular classrooms, a 3 x 6 in our learning studios where faculty members are teaching other faculty how to teach with technology, and in the auditoriums of our health science campus, which is part of our medical school, two 5 x 5 configurations.”
According to Alan C. Brawn, president, Brawn Consulting, factors that are contributing to the increased use video walls are:
- The lowering of flat-panel prices.
- New lighter panels with thin bezel designs.
- Longer duty cycle displays capable of 24/7/365 operation for lower TCO.
- Increased capabilities of the video processors driving the video wall. These used to be very expensive hardware devices, but processing power has, of course, come down in price.
- The introduction of less costly video wall processors such as the new software-based processors coming out of Hiperwall.
- Less expensive content for video walls.
Who’s Using Video Walls and Why
Video walls can be found at corporate headquarters like JetBlue’s corporate headquarters, colleges, hospitals, airports, convention centers, sports arenas like Miami’s American Airlines Arena and elsewhere, like the Western States Information Network in Sacramento, California.
The largest application for video walls, according to Brawn, is retail. “Number two is command and control, rental and staging third, arenas and stadiums fourth, and corporations fifth.”
The most significant benefit of a video wall, says Brawn, is “the ability to use it to enhance an environment. We call this ‘techorating’ — where the technology becomes a part of the interior design.”
Also, having the larger display area lets you do more than what you could with a single larger, but smaller than a video wall, display, according to Brawn.
St. Louis University’s reasons for doing the two larger displays as video walls rather using projectors included TCO and shorter time-to-repair — an hour to swap a display in versus one to two days to replace a bulb, says St. Louis U’s Williams. For the others, the greater resolution brightness of video displays compared to projection was important. “We can have all the lights on and the windows uncovered, and still see what’s being displayed,” according to Williams.
The Components of a Video Wall
The components of a video wall are largely similar to those for digital signage: displays and mountings, content management software, content player and, as needed, power and networking.
As with digital signage, the flat-panels used for video walls are typically the enterprise/commercial-grade ones, which, while more expensive than their home-theater cousins, offer the greater reliability for 24×7 operation, environmental durability, better warranty, control for remote/central management and other necessary features.
One difference between whatever the biggest individual display you can buy and a multi-display video wall is the potential resolution.
It’s possible to connect the displays and spread a standard hi-def image across them. Many flat-panel displays incorporate enough video processing power built directly into displays to let you “inflate” a 1920 x 1080 image across a 2 x 2 matrix of screens.
However, Jeff Greenberg, CEO of Hiperwall, which provides video processing software for video walls and other multi-display configurations, points out, “then you don’t get to leverage the resolution of all the monitors. You’re simply expanding one image to a larger size, with ‘fat pixels.’ For example, a 4 x 5 wall of 1080p displays gives you 20 times 2 million pixels — a 40 million pixel canvass. But if you use a DVI video source that is only 2 million pixels, the result will look grainy to anybody within 20 to 30 yards.”
To leverage the full resolution of all the monitors, rather than expand an image into “fatter pixels,” you’ll need additional video processing power and capabilities, either a software-based solution like Hiperwall (which will require hardware) or appliances. “A video processor can split up an image or video among displays, send different information to separate displays,” says Greenberg.
“The content you want to show determines whether you can use simple built-in processors in the displays or need external video processors to provide the resolution you want,” says Dennis Pappenfus, general partner at Fluid Sound, an audio video systems integration and contracting company. “And you may need source content produced at that higher resolution.”
The right content management software is also key, since video walls call for not just pushing content to multiple displays, but also coordinating the multi-screen view.
For example, Sony’s Ziris Canvas software for managing video wall and digital signage content includes an alignment chart for video walls,” says Andre Floyd, Marketing Manager, Professional Displays and Digital Signage, Sony. “Ziris can create a PNG file describing where each pixel on the screens is, for use as an overlay in a content creation package. This is particularly useful if your video wall isn’t one big rectangle.”
While there are cameras providing slightly higher resolution than standard hi-def, “mostly this higher-def comes from the content creation house,” notes Hiperwall’s Greenberg.
Video Walls for “Wow”
“A well-executed video wall gives you that ‘wow’ factor — it gets you and your message noticed,” says Ben Hardy, senior product specialist, NEC Display Solutions. “Corporations are using video walls for locations like lobby entrances, and we’re seeing a lot more video walls in higher education, especially for things like alumni and donor walls. Retail is big, of course. And there’s a lot of specialty uses for video walls, like broadcast sets and performance stages.”
“We’re starting to see video walls move more into entertainment, versus front or rear projection,” says Fluid Sound’s Pappenfus. “Also in disaster/emergency operations; e.g., San Diego’s American Red Cross [where] instead of a giant white board and maps, [a video wall] lets them dynamically update content. That really changed their overall response time.”
Also, according to Phil Borkowski, general partner, Fluid Sound, video walls are also good for places like art galleries, museums, airports and other venues instead of using, and having the potential cost of periodically updating or changing, traditional static imagery, paintings or murals.
Lastly, says Borkowski, “Video walls today don’t have to just be done in the traditional fixed-aspect ratio of a single display. They can have a variety of sizes, shapes, screen orientations, even non-contiguous. This opens up creative opportunities.”