Accessible video – Why it matters in 2020
It was great to see Wistia launch a new version of their video player in January that puts accessibility at the heart of their offering. While huge steps have been taken in recent years to remove some of the barriers that people with disabilities face in many aspects of life, the internet has often lagged behind.
And yet there are huge segments of the population for whom the typical designed online user experience is simply not available:
- Official statistics for 2016-2017 put the number of people with disabilities in the UK at around 13.9 million, or 22% of the population.
- 2 million people have varying degrees of sight loss, with 360,000 registered blind or partially-blind.
- Around 11 million people have hearing impairments, of whom 900,000 are severely or profoundly deaf.
- Motor impairments, cognitive impairments and even colour-blindness can negatively affect website accessibility.
In this blog, we’ll look at some of the best practices for making sure online videos are accessible to the greatest numbers.
#1 Provide Subtitles
Subtitles convert the speech in your video into type which is displayed on screen simultaneously.
As well as providing a well-established alternative to audio for people with hearing impairment, subtitled video has two other advantages:
- Huge numbers of people choose to consume video with the sound off. The figure is as high as 85% for Facebook videos!
- Search engines can index a subtitle file far more effectively than video audio, making subtitled videos more easily discoverable.
#2 Provide Other Text Alternatives
Captions are not the same as subtitles. Captions provide more detail, describing on-screen what is happening and non-verbal sounds. Without this extra information, subtitles can miss a lot of the meaning of video content.
It is also often a good idea to provide a Transcript: that is, a complete text account of the video dialogue and action which can be viewed separately. Again, that is great for SEO, but it is also very valuable for hearing-impaired people who also have difficulty reading at speed.
#3 Use Audio Description
Audio description fulfils the same function as captions for people with visual impairments. An audio description track will play alongside the main audio track explaining what is happening in the visuals.
#4 Large Text, Contrasting Colours
For people with mild visual impairments, small text, text that changes too quickly and insufficiently contrasting colours can make a video incomprehensible.
If you use text in animations (or subtitles and captions!) make sure the type is large and that it stays on screen long enough for people with poor eyesight or low literacy to read it.
And use bold colours that stand out to compensate for poor colour perception.
Nevertheless, it is best to avoid conveying information by colours alone as some people will not be able to differentiate them at all.
#5 No Autoplay
Many visually-impaired people use screen readers when online. A screen reader uses a Text-To-Speech engine to convert on-screen information into audio (or sometimes Braille).
Videos that start automatically can severely interfere with screen reader use. Two audio tracks playing at once can be very confusing. So make sure you do not set videos to autoplay.
#6 No Flashing Imagery
Photosensitive epilepsy can be triggered by flashing on-screen images.
Famously, one episode of the cartoon series Pokemon caused 700 viewers to have seizures in 1997.
Fortunately, tools are available that can analyse your content for epilepsy trigger risks.
#7 Use an Accessible Player
So much for the content. What about the video player itself?
The WCAG 2.1 standards recommend that players should be completely controllable:
- By keyboard AND
- By mouse
Many players that need a combination of both cannot be used properly by people with various motor impairments.
Similarly, application behaviour and navigation should be as predictable and intuitive as possible to help people with cognitive impairments to use them. Provide information on using the player in a prominent location.
To help people with poor eyesight:
- Make control buttons large and clearly contrasted with surrounding space
- Minimise transparency and overlays
Of course, all these things involve more work for organisations producing video content.
But the extra effort must be weighed against the benefits.
On the one hand, the ethical importance of making the internet accessible to all. And on the other, the wider audience accessible video content will give you.
For more details on the Web Content Accessibility Guidelines 2.1 from the W3C see this guide.