To mark the opening of nominations for the EBU Technology & Innovation Awards 2021, we're looking back at the projects honoured in 2020. BBC's Accessible and Enhanced Audio project was one of three runners-up for the T&I Award 2020. This article first appeared in Issue 46 of tech-i magazine.
Matthew Paradis (BBC R&D) and Lauren Ward (University of York*)
The Accessible and Enhanced Audio trials represent a great advancement in personalized audio – putting the viewer in control of their broadcast audio experience. The project successfully developed and tested a novel approach, providing the viewer with a simple, single-slider control with which they can adjust the complexity of the audio mix as easily as changing the volume. By engaging directly with production teams and end users, this approach addresses an ongoing broadcast challenge: to improve the experience for viewers with hearing loss.
Hearing impairment affects the ease with which one in six people in the UK access audiovisual content. Hearing impairment not only causes the sounds in the world around you to be quieter but can often cause speech to become jumbled and unintelligible, particularly when there are many other competing sounds. This is why increasing the volume doesn’t necessarily make the content easier to understand – it just makes everything louder. To make content accessible, audiences need to be able to adjust the level balance of different audio objects.
Using Next Generation Audio (NGA) codecs is what makes this possible. Our approach allows content producers to embed the narrative importance of different audio objects into metadata. This improves on previous approaches, where content producers were not as involved. Our approach ensures that producers’ creative intent is retained while comprehension of the narrative is maintained for the viewer.
This work represents a big step forward in accessibility, which our research shows is welcomed by viewers: 92% indicated they wanted to see more content like this. The first trial, in 2019, reached an audience of over 6,200 and gained high-profile media attention. Responses were overwhelmingly positive, with 84% of respondents saying the control made a difference, mostly either making the content more enjoyable or easier to understand.
“We are in charge of what we hear, and I think that’s quite empowering.” These were the words of a participant in a hard- of-hearing focus group in 2018, describing what this type of audio personalization offers. The benefits go beyond this, as user trials show, with young normal hearing listeners seeing the advantage of adapting the audio to their preferences and listening environment. Production teams, too, see this as “liberating for the content creator, who could make a mix more like the one they love without having to worry quite so much about those with hearing difficulty or in a noisy environment” (production staff survey participant, 2019).
By giving the audience the tools to adapt the media to their individual needs, broadcast content can not only be more accessible, but also offer a more inclusive experience. In the words of Gabriella Leon (pictured above), deaf cast member of the long-running medical drama series Casualty, “the potential of this technology is incredibly exciting!”
We are grateful to the colleagues who worked with us on this project: Ben Shirley (University of Salford), Dafydd Llewelyn (Casualty Producer), Loretta Preece (Casualty Series Producer) and the Casualty post-production team.
*Lauren Ward was at BBC R&D and University of Salford until June 2020