Tech Talk: Creating Content for Video Walls — Part II

Posted on August 27, 2012

Product Engineer Anthony Chiappone proudly stands in front of MVP panels.

Written by Product Engineer for CHAUVET Professional Anthony Chiappone.

Since video walls have become so desirable for large and medium shows, in my previous blog post, which you can read here, I explained why it is important to know when and how you should create video content. I focused on defining the resolution, the pixel pitch, and how these relate to video. Now, it is time to understand the application and the streamline process. Read on:

When selecting the design for the show, it is important to understand the desired outcome. If the intension of a video wall is to have live video (IMAG) played back on them, then you need to know the minimum viewing distance of the stage and also be sure to select an appropriate pixel pitch for this distance. In situations where you intend you play back motion graphics, the pixel pitch can be as low as 50mm, while still being effective. However, it is often good practice to use the following guideline when selecting video panels for an event where you intent to play back live camera/recorded footage.

Minimum viewing distance:
You should convert the pixel pitch to meters, and this is the closest that your audience should be at any time in order to comprehend what the video wall is playing back. For example, 12.5mm pixel pitch panels should only be seen at 12.5 meters, or 40 feet; although with increased distance the quality will look even better. This means that for indoor events in smaller venues, you would likely only want to use panels with pixel pitches of 3mm-12.5mm. And, for outdoor events with longer viewing distances, 12.5mm-40mm panels would be appropriate.

If you are using the LED video panels outdoor, you should consider safety and strength of the structure you are hanging from. If you are using a temporary truss structure, then you should be concerned about the wind blowing over a solid wall. Therefore, the following words should be included in the product description: transparent, blow-through, and sometimes curtain (not used for flexible panels, but rather panels made of strips). This allows the wind to pass through the gaps in the panels, rather than blowing them over. This also is something that you should consider when selecting your pixel pitch, because larger pixel pitches provide greater transparency. Something else you should consider is the local weather. If you are using the video wall in an area that has frequent rainstorms, you should make sure that the panels have some degree of ingress protection (IP rating of 50 or higher). This does not need to protect against permanent outdoor installation. But, it should be sufficient for unexpected rainstorms.

How to streamline the process?
Keep in mind that many video playback software have the ability to grab certain portions of a single video file and send them to individual sections of your video wall. One of these is ArKaos MediaMaster Express. If you are using the Express version of the software, then you have the “cropping” tool. This is invaluable, as it simplifies the preproduction of your shows, and allows you to do most of your conversions to accommodate different pixel pitch panels in the same show, playing back the same content. With this tool, you no longer have to render custom video files 24-48 hours before the show time. Keep in mind that when you are using this technique, you should not apply any masks to the video content, if rendering it.

This miniseries on how to create video content should give you enough info to start rolling, but remember you have to conduct research on your own, as well, in order to keep up with the new technologies. Don’t be afraid to invest hours of practice and don’t forget to have fun!