Industry & future

What AI Changes, and Doesn't, for Accessible Video

AI has made captions, transcripts and translated audio cheap and fast enough that far more video can be made accessible than before. The catch is that automatic output contains errors, and those errors fall hardest on the people who can't check them against the audio, especially deaf and hard-of-hearing viewers. AI also leaves major gaps untouched, such as audio description and sign language, so it works best as a fast first draft inside a process with human review.

6 min read · Updated

What AI actually changed

For most of the history of video, captions were produced by trained human captioners, which made them high quality but expensive and slow. Many organizations captioned only flagship content, and the long tail of internal updates, webinars, short clips and archives went without.

Automatic speech recognition changed the economics. A transcript and a timed subtitle file can now be generated in minutes for a fraction of the old cost, and machine translation and synthetic voices extend the same content into other languages. The result is a real expansion of what can be captioned, not a perfect replacement for what human captioners do.

Who benefits, and in what way

  • Deaf and hard-of-hearing viewers get captions on video that would previously have had none.
  • People watching in a second language can read along, slow down and look words up, and translated subtitles open content in languages the original never targeted.
  • People with auditory processing differences, attention-related conditions or some learning disabilities may follow text more easily than speech.
  • Blind and low-vision viewers can follow foreign-language content through translated audio, which subtitles alone don't offer.
  • Anyone in a noisy place, or one where sound must stay off, can still follow the content.
  • Transcripts make spoken content searchable and readable with screen readers and braille displays.

These are genuine gains. The important caveat is that the benefit depends on accuracy, and the people relying most on the text are often the least able to spot mistakes.

Why errors hit deaf viewers hardest

A hearing viewer who sees a wrong caption hears the right word and shrugs. A deaf viewer has nothing to compare against. The caption is the content, so an error is not a distraction but a false statement.

The errors that matter most are rarely the obvious ones. A misheard name, a wrong number, a dropped "not" or a confident line generated during music or silence can change meaning while looking perfectly fluent. Whisper and similar models occasionally produce text that was never spoken, a failure described in Whisper hallucinations. Automatic captions also usually lack speaker identification and sound cues such as alarms, laughter or music, which captions for deaf viewers are expected to include; the difference is explained in captions vs subtitles.

Translation and synthetic voices: new access, new failure modes

Translation stacks a second source of errors on top of recognition. A misrecognized word becomes a mistranslated sentence, and viewers reading a translation usually cannot consult the original. For safety, health or legal information, that makes review by a fluent speaker essential rather than optional.

Synthetic voices raise different questions. A dubbed track can make content accessible to people who can't read subtitles quickly, including some blind viewers, people with dyslexia and young children. But a single synthetic voice for several speakers can make it harder to follow who is saying what, and a voice that mispronounces names or misplaces emphasis can mislead in ways a listener cannot detect.

Gaps AI doesn't close

Some access needs sit almost entirely outside what speech-based AI does.

  • Audio description, which narrates visual information for blind and low-vision viewers, is a different task from captioning; audio description vs subtitles explains why.
  • Sign language interpretation serves Deaf people whose first language is a sign language, for whom written captions in a second language are not equivalent; see AI and sign language translation.
  • Plain-language versions, simplified scripts and cognitive accessibility depend on how content is written, not on how it is transcribed.
  • Accessible players, keyboard navigation and caption styling are platform features that no caption file can fix.

Example: a nonprofit's monthly update

Example: a 12-minute video update

A community health nonprofit publishes a monthly video. Until now it went out uncaptioned because human captioning wasn't in the budget. The team generates English subtitles automatically and spends 20 minutes correcting the clinic names, phone numbers and one dropped "not" in a sentence about eligibility. They also produce a Spanish dubbed version, which a bilingual volunteer checks before it is posted.

The point of that example is the 20 minutes. Generating the files took a few minutes and cost very little; reviewing them is what turned automatic output into something the nonprofit could stand behind. The guidance for formal settings such as schools and universities is set out in captions for educational video accessibility.

A review routine that keeps AI captions trustworthy

  1. Generate captions or subtitles from the final edit of the video.
  2. Proofread against the audio, prioritizing names, numbers, dates, negations, instructions and technical terms; proofreading an AI transcript has a method.
  3. Add speaker identification and meaningful sound cues where the file will serve as captions for deaf viewers.
  4. Split long cues so each is comfortable to read at playback speed.
  5. Have a fluent speaker review any translation, especially for health, safety, legal or financial content.
  6. Publish with a visible way for viewers to report caption errors, and fix reports promptly.
  7. Involve disabled viewers in testing when you can; they notice problems checklists miss.

Mistakes organizations make with AI accessibility

  • Publishing unreviewed automatic captions and describing the video as fully accessible.
  • Assuming a policy or law is satisfied by captions alone, when it may also cover description, transcripts or player accessibility. This is general information, not legal advice; check the rules that apply to you.
  • Using AI output for live or emergency information without a human able to correct it.
  • Treating translation into a written language as equivalent to sign language for Deaf audiences.
  • Reviewing only the first few minutes and missing errors later in the file, where speaker fatigue, music or crosstalk often appear.
  • Not asking disabled people what they actually need.

Where mydubly helps and where it stops

mydubly's subtitle generator produces a transcript, a timestamped transcript and SRT and VTT subtitle files from a video or audio file, in the spoken language or one of 21 target languages, and the video translator can add a dubbed version with a stock voice. That covers the fast first-draft step for captions, transcripts and translated audio.

It does not cover the rest. mydubly doesn't add speaker labels or sound cues, doesn't burn captions into the picture, doesn't create audio description, doesn't translate on-screen text and doesn't produce sign language. Each cue is one speech segment on a single line, so review and line splitting happen in a subtitle editor. For the nonprofit example, subtitles cost 12 credits (1.2¢) and a Spanish dubbed version 600 credits (60¢); the human review is the part that makes them accessible. The guide to adding subtitles to a video covers getting the reviewed file onto your platform.

Draft with AI, finish with people

Use AI to caption and translate the video that would otherwise go without, then review what viewers will rely on and fill the gaps AI doesn't reach. A practical start is to run one recent video through the subtitle generator and time how long a careful review takes.

Frequently asked questions

Are automatic platform captions good enough for accessibility?

Often not as published. Automatic captions on video platforms can be a useful starting point, but they typically contain recognition errors and lack speaker identification and sound cues. Accessibility guidance generally expects captions to be accurate and complete, so treat platform captions as a draft to correct or replace with a reviewed file.

How accurate do captions need to be for deaf viewers?

There is no single universal number, and broadcast and education rules differ. In practice, what matters is that meaning is preserved: names, numbers, negations and instructions must be right, and the captions should reflect who is speaking and important sounds. A file that is mostly correct but gets one key instruction wrong can still fail its viewers.

Can AI-generated voices be used to make video accessible?

They can help some audiences, such as people who can't read subtitles quickly or blind viewers following foreign-language content. They don't replace captions for deaf viewers or description for blind viewers. Check pronunciation of names and terms, and consider labeling synthetic voices so listeners know what they are hearing.

Who should review AI captions in a small organization?

Ideally someone who knows the subject and can listen carefully, such as the presenter or a colleague familiar with the names and terms. For translations, a fluent speaker of the target language is essential. If the content is high-stakes, such as health or legal information, consider a professional captioner or translator for the final check.

Does adding captions make a video's SEO better as well?

Captions and transcripts can give platforms and search engines more text about a video, which may help discoverability, but accessibility is the stronger reason to add them. The YouTube captions and SEO article looks at what captions do and don't do for search.