Deaf News: Ofcom publishes fourth report into live subtitles, saying delay is too long

Ofcom has published its fourth and final report measuring the quality of live TV subtitles in UK programmes.

Over the past two years, Ofcom has required the BBC, ITV, Channel 4, Channel 5 and Sky to measure the quality of their live TV subtitles, helping to identify areas for improvement that could benefit the millions of viewers who use subtitles.

Today’s report shows that the overall accuracy of live subtitling remains very good, at over 98%.

However, the average ‘latency’ of subtitles – the time lag between words being spoken and the corresponding subtitles appearing on screen – was 5.6 seconds, well above Ofcom’s recommended level of three seconds.

The majority of samples measured, reviewed by experts at the University of Roehampton, also had instances when subtitling was likely to be too quick for viewers to follow, often as a result of pre-recorded subtitles being speeded up to reduce latency.

Since Ofcom began publishing these reports in 2014, broadcasters have engaged in discussions about improving the quality of live TV subtitles on their channels.

The BBC and Channel 4 are exploring a new approach that would take advantage of delays inherent in the processes for video, audio and subtitling – so-called ‘switchable delays’ – to reduce the latency of subtitles significantly. The BBC intends to start implementing this solution on some of its channels next year, while Channel 4 has committed to trialling this method. Both will share their results with other broadcasters.

Ofcom’s reports have shown that trade-offs sometimes need to be made between different aspects of subtitling quality, such as latency and speed. Ofcom intends to commission further research to understand how subtitle users would prefer these trade-offs to be struck.

Following publication of this research in early 2016, Ofcom will consult on whether changes to its guidelines and rules are necessary.