March 20, 2025

HbbTV interoperability plugfests: A developers perspective

Introduction

Three times a year, the HbbTV Association supports industry interoperability ‘plugfests’ arranged by several organisations. A plugfest is an event where developers and engineers from different organizations come together to test the interoperability of their products, systems, or software implementations. The goal is to ensure that different vendors’ products work seamlessly with each other according to established standards or protocols.

Since I started working on the HbbTV Developer Portal, I’ve been trying to get someone to write about the application developer experience at the various plugfests. I wanted to be able to tell HbbTV application developers how the events work and what they would get out of them.

As the February 2025 plugfest, jointly organised by DTG and DTVP, was in my hometown London, I decided that I would go along and experience it for myself.

Anyone can attend a HbbTV plugfest as long as you have something to actively test, there are no observers allowed. All you need to do is register and then sign the participation agreement. HbbTV members can go for free, as do members of the organisations organising the event (DTG and DTVP in the case of London), non-members need to pay a fee, for London this was £700 plus VAT for one participant and  £300 plus VAT per additional participant.

The participation agreement has some strong confidentiality clauses. These are important as they ensure that everyone is open to participate and collaborate. This means you can’t openly share what you see or hear at a plugfest, which can make it a little difficult to write about. But I’m safe to write about the processes and what I got out of it, though I can’t tell you which devices did what.

London event

I registered for the London event hosted at the DTG office as an HbbTV application developer with applications to test. 

As a developer I was allocated a 45-minute slot with each of the TV manufacturers attending, across the two and half days of the plugfest. The organisers had kindly grouped my sessions into one and half days, so I did not need to attend for one of the days.

I was then free to use the each of 45 minutes sessions I was allocated, as I saw fit. There were six major TV manufacturers attending the event and I was therefore allocated six sessions.

I turned up with two test applications and a playout set-up using a Dektec DTU-215. One application was a simple one that accessed the capabilities and configurations APIs; I had written this application as part of a tutorial I’m working on for the developer portal. 

The other application was to test the ability of HbbTV implementations to support responsive web frameworks. While the most well-known of these is React, I had an application developed in Vue.js. The application had been developed as a responsive mobile and PC web application, to which I had made minimal changes to make it run on an HbbTV device.

At the start of each session, we connected my playout set-up to the test television. I discovered with my first session I didn’t have a long enough cable, but I was loaned one for that session and then DTG found me one for the rest of the event.

Once connected the television would be made to scan for my signal and then the testing would start. It was helpful to know which DTT channel my application was on to enable a quicker manual scan rather than waiting for an automatic scan to cover all frequencies.

The testing went well, but I did encounter problems. One annoying error was I had a space at the start of my URL in the AIT for one of my application streams, this was fine on the first televisions I tested it against, but another television refused to start it. The manufacturer debugged the situation and was able to tell what was wrong and I was able to retest once I had rebuilt my AIT.

I had a few other problems and each time the manufacturers would use their debug tools to help identify each problem, for me to correct.

Once I had resolved all the issues with my code both applications worked as expected across the seven television sets I tested them on. The key outcome was my Vue.js application ran consistently across television, this included broadband video playback using dash.js.

All the televisions were 2025 models, supporting either HbbTV version 1.6.1 (2.0.3) or 1.7.1 (2.0.4), it would be interesting to know if older televisions can also support an application framework such as Vue.js, but that is a different activity all together.

HbbTV testing was not the only purpose of the plugfest, there was HDMI testing and the opportunity to test other emerging technologies and content formats. 

Alongside each of the plugfests, the HbbTV Association also holds a testing event and its testing group meeting. The testing event is used to test pre-releases of the HbbTV test suite. 

The London event was very well organised and hosted by the DTG, this included the catering which was also very good and plentiful.

Checklist

To get the most out of the plugfest, I recommend the following:

1. Have a clear objective out of what you want to achieve from the testing
2. Test and debug your application as much as possible on an HbbTV implementation before attending the event
3. Plan your testing, ideally with a test plan and test steps
4. Determine how you will record your testing
5. Have all the equipment and files you need to run your tests

Summary

I would recommend any developer to attend a plugfest to test their application on a range of new television models, it is also a great way to network with the wider HbbTV community and the TV manufacturers. If you are tackling a complex technology (e.g. MediaSwitcher) it is a great way to get access to the manufacturers debugging tools. 

I found everyone at the event welcoming and helpful, with a common objective to get value out of the testing and the event as a whole.

Matthew Huntington
Manger of the HbbTV Association Developer Programme