Thousands of children participate from their homes via webcam in a German ZDF children's contest

Ventuz technology applied to the German children's contest 'Web vs. Promi’ allows viewers to compete from home against a celebrity in the studio. Contestants participate using their webcams and a shader-based motion sensor.

One of the biggest challenges for television today is to achieve viewer participation. Building a bridge between the studio and families in their homes is one of the greatest aspirations of television, and audiovisual producers, creators and directors continue to look for innovative solutions to achieve this.

German public television ZDF has been considering this idea for years, an interactive contest for children, where kids can play with each other from their homes, moderated by a presenter in the studio. Several pilot programs were made for KiKA, the ZDF channel focused on children.

Most of them consisted of various questions and challenges, such as collecting all the objects that a boy could find around his house in a certain amount of time. Although advanced systems were used, all programs ran into the same problem, too much delay in the video signals.

All of this caused communication between the participants and the study to be very rigid and complex, which not only hindered the participation of the contestants, but also affected the general rhythm of the entire program.

Finally, the project ended up falling into the hands of the Munich-based Rayd agency. “When they called us, the ZDF had already decided to take a more complex approach to the program,” explained Oliver Grimm of Rayd. "They wanted to incorporate video games so that children could play from their screens against a famous person on the set. But they still had the problem of lag, which meant a double challenge for us."

Rayd, with his extensive experience in broadcast technology and contest development, completely changed the workflow, starting from scratch. “We started with the video communication system,” says Johaness Klaer from Rayd, “she quickly realized that none of the usual systems could work for this project.”

They created a Flash-based plugin for internet browsers so that kids could access it simply by opening a specific page on the internet, without having to install any additional software on their computers. This reduced the delay of the 6 incoming video sources, four contestants and two alternates, to less than half a second.

Another great challenge was the creation of the games, Rayd created a wide variety of them, from adaptations of classics like Pong, to flight or racing simulators.

The contestants participated using their webcams and a motion sensor based on a shader developed for the program, which followed the contestants' movements and transferred them to the game environment. On their home screens, children could watch the game superimposed over their own video signals. For the second season of the show, Rayd added voice commands to the games to make them even more interesting.

With three data sources for each contestant, video, audio, and motion sensor data, the contest server really had its work cut out for it. In addition to handling the contest logic, the software had to calculate all the scores and rankings, and transmit that information to the control system, another of Rayd's own developments.

El workflow

The ultimate goal was to gather all that information (video feeds from the contestants, real-time game feeds, scores, and camera images) into an HD signal for broadcast. For this purpose, Rayd used three systems with real-time graphics software sucker. In total, three servers were installed, each controlling a specific aspect of the program. One machine was equipped with a Deltacast HD video capture card, which allowed two HD video inputs, one with the game render in real time, while the other received the six video signals from the contestants and the celebrity on the set, all of them in a multiple signal. "We created a masking function in Ventuz, to control which areas of the split screen appeared at certain positions in the broadcast. This allowed us to place the contestants' video feeds exactly where we needed them," explains Oliver.

A second Ventuz system was used to generate real-time on-air graphics. Rayd created a large number of graphics frameworks in Ventuz Designer, each according to the aspect of the game in which the graphics would be placed. Then the video feeds of all the participants were distributed around the game area, and their names and additional information were added as another layer of additional text. The Ventuz scene received this information from the control software using a .NET-based protocol.

Between games, Ventuz's system also handled the graphics with the rankings, “the first leaderboard to include real-time video of the contestants in the history of television,” says Johannes. A third machine with Ventuz was used to generate the content for the on-set video wall, an HD rear projection that presented all the information to viewers in the studio and showed scores and rankings, as well as real-time, full-screen videos of the kids at home.

Ventuz has been Rayd's go-to real-time charting system for many years. "There is no software on the market that can compete with Ventuz," commented Oliver, "and of course the price is a big advantage, but what really makes the difference is what you as an agency can offer to clients. Ventuz has so many little tools and options that help you design really attractive graphics, including advanced animations, but at the same time, you can work really fast. So even on a very tight budget, the graphics can look like high-end professional graphics."

The two seasons of Web vs. Promi They have been a success for the KiKA and ZDF channels, with a screen share of around 17%, a figure that also increased over time. Although the second season ended in 2013, all episodes continue to be broadcast regularly, still achieving a notable audience. Web vs. Promi was nominated for the Emmy Awards for digital programs in 2013. Until now, no other production has achieved such a level of interactivity with viewers at home.