Fixes by subject · 43 techniques
How to Fix Video, Audio and Media
Captions, transcripts and audio description are three different obligations, and almost everybody treats them as one.
Captions serve people who are deaf or hard of hearing. Transcripts serve screen reader users, deafblind users reading braille, and anyone who would rather read than watch. Audio description serves people who cannot see what the picture is showing. They are not interchangeable. There is one exception worth knowing. 1.2.3 is met by a full text alternative or by audio description, so a proper transcript discharges a Level A obligation most people believe needs a narration track. The techniques here cover all three, plus sign language interpretation, media alternatives, and giving people control over sound that starts playing on its own.
All 43 techniques
They run in technique order, and each one carries a tag. Sufficient techniques satisfy a rule. Advisory ones help without being required. Failures document a specific way of getting it wrong. None of them is mandatory, because W3C publishes techniques as documented ways of meeting a criterion rather than the only ways, so your own approach conforms as long as it meets the criterion.
- G87Sufficient1.2.2, 1.2.4Add captions to every video with speech
- H53Sufficient1.1.1, 1.2.3, 1.2.8Give object elements meaningful fallback content
- H95Sufficient1.2.2Add caption tracks to your videos
- H96Advisory1.2.1, 1.2.3, 1.2.5, 1.2.7Add audio description tracks to video
- SM1Sufficient1.2.3, 1.2.5, 1.2.7Add extended audio description in SMIL 1.0
- SM2Sufficient1.2.3, 1.2.5, 1.2.7Add extended audio description in SMIL 2.0
- SM6Sufficient1.2.3, 1.2.5Add audio description in SMIL 1.0
- SM7Sufficient1.2.3, 1.2.5Add audio description in SMIL 2.0
- SM11Sufficient1.2.2, 1.2.4Add caption text streams in SMIL 1.0
- SM12Sufficient1.2.2, 1.2.4Add caption text streams in SMIL 2.0
- SM13Sufficient1.2.6Add a sign language video stream in SMIL 1.0
- SM14Sufficient1.2.6Add a sign language video stream in SMIL 2.0
- F8Failure1.2.2Do not publish captions that skip dialogue
- F23Failure1.4.2Do not autoplay audio without a stop control
- F30Failure1.1.1, 1.2.1Never use filenames or placeholders as alt text
- F67Failure1.1.1, 1.2.1Do not write long descriptions that miss the point
- F74Failure1.2.2, 1.2.8Do not leave a media alternative unlabeled
- F75Failure1.2.2Do not skip captions when a video adds content
- F93Failure1.4.2Do not autoplay audio without a way to stop it
- F113Failure1.2.5Do not leave dialogue pauses empty of description
- G8Sufficient1.2.3, 1.2.5, 1.2.7Provide a version with extended audio descriptions
- G9Sufficient1.2.4Caption live video streams in real time
- G54Sufficient1.2.6Include a sign language interpreter in videos
- G56Sufficient1.4.7Keep background audio 20 decibels below speech
- G58Sufficient1.2.3, 1.2.8Put the media alternative link beside the media
- G60Sufficient1.4.2Silence automatic audio within three seconds
- G69Sufficient1.2.3, 1.2.8Provide a full transcript of the media
- G78Sufficient1.2.3, 1.2.5Offer a selectable audio description track
- G81Sufficient1.2.6Offer a synchronized sign language video track
- G93Sufficient1.2.2, 1.2.4Provide open captions burned into the video
- G150Sufficient1.2.9Provide live text for live audio-only content
- G151Sufficient1.2.9Link live statements to their prepared script
- G157Sufficient1.2.9Caption live audio with a captioning service
- G158Sufficient1.2.1Provide transcripts for audio-only content
- G159Sufficient1.2.1, 1.2.8Provide text alternatives for video-only content
- G160Sufficient3.1.5Offer sign language versions of essential content
- G166Sufficient1.2.1Add described audio for silent video
- G170Sufficient1.4.2Put a mute control before auto-playing sound
- G171Sufficient1.4.2Play sound only when the user asks
- G173Sufficient1.2.3, 1.2.5Offer a described version of every video
- G203Sufficient1.2.3, 1.2.5Describe talking-head video with static text
- G226Sufficient1.2.3, 1.2.5Narrate visual content within the soundtrack itself
- PDF7Sufficient1.4.5, 1.4.9Run OCR so scanned PDFs contain real text
More on Video, audio and media
The other 13 subjects
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