How volunteers from all over the world create live ICPC-2019

My name is Lida Perovskaya, I work at Yandex, and since 2015 I have been helping to organize the live broadcast of the International Collegiate Programming Contest. The ICPC, the student programming world championship, has been held annually since the 1970s. This is almost the only Olympiad of this level, which is being developed thanks to the efforts of hundreds of volunteers from all over the world. Today I will tell Habr readers about how my work on the ICPC is arranged from the inside. I also invite you to watch the broadcast of the event and try your own strength in solving the problems simultaneously with the participants.

For us, the volunteers, it is important that the event be interesting and useful both for the participants and for the audience. But it's not easy to do. For the final alone, 135 teams from 110 countries are announced, each team has three members, and they all participate at the same time! Who, when and how to broadcast? What code to show? How to comment on this to be useful?
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Let's start with the conditions of the problem.

So, in a huge hall, several hundred people write code locally and send it to the server for verification, the result of which determines their position in the final table. Everything is familiar to any contestant. And in our headquarters - the directing studio - only five or six volunteers determine what the audience will see right now.

It is not algorithms or even universities that participate in the Olympiad, but people. The final is their finest hour. According to the rules of the Olympiad, the same person cannot reach the final more than twice. Therefore, it is important to show first of all people: their emotions, teamwork. To do this, the participants are fixed stationary cameras AXIS V5915.



You can direct the camera to one or the other team. We used to manage cameras manually. This year we wrote a software that knows the coordinates of each team and can “look at” it automatically if the team did something interesting. Robots take our jobs.

But stationary cameras can not cover everything that we need. Mobile group helps: three or four people who are ready at any time to approach the participants. Such a shoot looks more natural.

Equipment for mobile groups is prepared again by volunteers. We use what is already on the market, combine and finish it on our own. Our mobile kit this year looks like this:



In 2015, we received the picture “from the playground” from ordinary professional video cameras connected via a wire that had to be pulled. Later switched to wireless. And this year we changed the GoPro cameras to a gyro-stabilized version, so the picture even with such a compact installation looks smooth and professional.

We add interviews with teams to the live video. Interviews are recorded in advance and mixed into the broadcast on a schedule, which automatically includes video through a self-made plug-in for OBS. Schedule during the broadcast may vary.

With the video it became a little clearer. But we have the same programming contests, which means that we need to show the tasks and code that participants write. And so that it was interesting.

On the technical side, everything is simple. Complexity in the organization: how to decide who and when to show?



Fortunately, we have analysts. A special team monitors the progress of the participants, finds the most interesting solutions and transfers them to the director's studio. Thanks to regular backups, analysts see all the code: both already sent for review and not yet sent. In addition, they are able to "predict" the most interesting events. For example, if a team’s decision can lead it to leadership, then it is worthwhile to send a signal to those responsible for the video, so as not to miss the emotions of the participants when the results appear. Did a small change in the code allow the team to correct the error and successfully complete the task? Urgently in the room! Do rivals fight for victory and the score goes on for seconds? Let us show them a close-up stand-off to see what they are doing. All this makes the broadcast more dynamic and interesting.

And analysts help with the analysis of tasks.



Do not forget about the commentators. Without them, live broadcast is not so interesting, and the audience is difficult to understand what is happening. We have ten commentators in our team: two people for Russian, English, Chinese, Portuguese and Arabic versions. They receive real-time information from analysts to attract viewers to interesting events.

Content from the mobile group, analysts, commentators, and other sources is drained into the director's studio, where we manage the air on the fly. It is difficult, but very interesting.



This year we will be broadcasting ICPC in Yandex.Even, on YouTube and Twitch, on VKontakte and on some other sites. What would you like to see in the broadcast? Who do you think would be the perfect commentator for a programming competition?

By the way, we recall that any viewer can informally participate in the Olympiad. All tasks will be available on the official website icpc.global. Send the solutions to the server for verification, and maybe you will overtake the finalists of ICPC-2019.

It will be interesting, cheer for ours!