Different people, different hearing
“Deaf and hard of hearing” covers a wide range. Some people are profoundly deaf and have no useful hearing. Others hear some sounds but not speech clearly, or hear well in quiet rooms but not in noise. Some use hearing aids or cochlear implants, and some do not. Some use a sign language as a first language, and for them written text in a spoken language may be a second language. Others lost hearing later in life and are used to reading.
Because of this variety, there is no single “deaf viewer”. Subtitles are a major tool for many, but not the only one, and the right approach depends on the person and the situation. This article is general information and does not speak for any one community.
Subtitles and captions are not always the same thing
In everyday speech the two words are often swapped, and the usage varies by country. A useful distinction, though, is between two kinds of text:
- Dialogue-focused subtitles. These show what people say, often so that viewers who can hear the sound but not understand the language can follow along. They assume the viewer can hear everything else.
- Captions for deaf and hard of hearing viewers. These also describe the sounds that matter, which a hearing viewer would take for granted.
The difference between captions and subtitles in terminology is a subject of its own. For this article, the key point is that a viewer who cannot hear the soundtrack needs more than the spoken words.
What the extra information includes
Sound carries a lot of meaning beyond speech. A viewer who cannot hear it may miss:
- Who is speaking, especially off-screen or in a group.
- How something is said, such as whispering, shouting or speaking through tears, when it matters to the scene.
- Sound effects that explain events, like a phone ringing, a knock on the door or footsteps behind someone.
- Music, including whether it is tense, cheerful or simply background, and sometimes the title or lyrics of a song.
Captions usually handle these through short notes in brackets or in a different style, and through labels for speakers. This kind of non-speech information is what turns a transcript of words into something closer to the full experience. Style practices differ between broadcasters and countries, and there is no single universal rule.
What a good experience looks like
Beyond content, several details shape how comfortable captions are.
Accuracy. Wrong or missing words are frustrating, and a viewer who cannot hear the original has no easy way to check. Automated subtitling can be helpful as a first draft but makes errors, and human reviewers are important when the content matters.
Timing. Text should appear close to the speech it matches. Lines that arrive late are confusing, particularly for viewers who lip-read or have some hearing and compare what they see and hear with what they read. Good subtitle timing and sensible display duration both matter. Sync drift, where captions slowly fall out of step with the picture, can ruin a whole program.
Reading speed. Viewers vary in how fast they read. Captions that include every word of fast speech can be hard to follow, while heavy condensing may leave out details some viewers want. Many guidelines try to balance the two, and viewers often have strong opinions about it.
Placement. Captions are usually placed at the bottom, but should move when they would cover important on-screen text or a speaker’s mouth. Viewers who lip-read particularly benefit from a clear view of faces.
Legibility. Clear fonts, good contrast and a suitable size make text easier to read. Many viewers like to change these settings themselves.
Live and recorded material
Recorded programs allow time for careful captions. Live events are harder. Live captioning is produced as people speak, either by trained people using specialist methods or by automatic speech recognition, and each has strengths and weaknesses. There is usually a delay, and live text can have errors. For news, sport, lectures and meetings, these limits are well known to deaf and hard of hearing viewers, who often report that live captioning quality varies a lot.
Captions are not the only answer
For people who use sign language as their main language, captions may not be the preferred option. A sign language interpreter or a version of the program made in sign language may serve them better for some content. Others find a combination best. Respecting these differences means offering more than one form of access and not assuming that text covers everyone.
Beyond the deaf and hard of hearing community
Captions made with this audience in mind often benefit many other people, including those watching in noisy places, people learning a language, and older viewers whose hearing has gradually declined. But the standards should be set by the needs of those who rely on them, not by those who use them as a convenience.
Rules about the provision of captions vary by country and by type of service, and they change. Organizations should check with the relevant authority or a qualified professional about what applies to them.