- Captions must be provided for all videos.
- Tips for writing captions
- Captioning services
- About transcripts and audio descriptions
Captions are synchronized transcriptions of audio content, displayed as an additional track on a video. At ASU, all online video must be captioned.
Captions are critical for many people--users who are deaf or hard of hearing, non-native speakers, people in noisy (or quiet) environments, individuals with cognitive impairments that make processing auditory information difficult, and others.
In a 2016 study by Oregon State and 3PlayMedia of 2,124 college and university students, 71% of students without hearing difficulties said they use captions at least some of the time, primarily to aid learning.
Reasons Students Use Captions
To view captions while watching a video, users click the closed caption icon.
Auto-caption your videos
We strongly recommend that ASU site owners and content editors host their video on YouTube. YouTube uses voice recognition technology to automatically add captions to most videos uploaded to its site. It's much easier to edit the captions supplied by YouTube than to create new captions from scratch.
To add a video to YouTube:
- Sign in to YouTube with your ASUrite. All ASU faculty, staff, and students already have an ASU/YouTube account.
- Click the upload link in the upper right.
- Select the video on your computer.
- Click Publish. (See YouTube's upload instructions for more detail.)
- When YouTube adds captions to your video, you must edit them.
Because voice recognition software isn't perfect, auto-generated captions are frequently inaccurate and should be reviewed and edited. A few hours or so after uploading your video, follow these instructions to review and edit the captions in your YouTube Account Manager.
What if my videos are hosted on Vimeo?
If your videos must be hosted on another platform, such as Vimeo, you can still use YouTube to create the captions. Temporarily upload your video to YouTube, then create and edit captions as suggested above. When you’ve finished editing the YouTube captions, you will download the caption.srt file:
- From your YouTube dashboard:
- Click on Edit and select Subtitles/CC.
- Under Published, click on English.
- Click on Actions and select SRT.
- The file will download as "captions.srt".
- Next, upload your video to Vimeo. When it's complete, upload the captions.srt file from YouTube to Vimeo:
- In your Vimeo account, go to My Videos.
- Click on the small gray gear icon in the left top corner of your video.
- Select ‘Advanced’ in the menu.
- Click the ‘Choose File’ button and upload the captions.srt file.
Save the video and test to ensure the captions are synched correctly.
Although not currently available, auto-generated captioning for MediaPlus is coming soon!
Meanwhile, see these MediaPlus captioning instructions to manually upload caption files (vtt and srt) for video hosted in MediaPlus.
Captions on library owned/licensed videos
If you'd like to use a library owned/licensed video in class or on Canvas but it is not yet captioned, add it to your Library Reading List and the library will automatically caption it. Your Library Reading List tool is in Canvas, or you can submit a Reserve Request Form and the library will activate the tool in Canvas and add the item for you.
Tips for writing and formatting captions
When captioning video, the goal is to convey the meaning and intention of the audio material, including sound effects, dialogue, accents, grammatical errors, pauses, music, etc.
- If it's not clear who is speaking among several speakers, identify the speakers by putting their names in brackets or parentheses or capitals followed by a colon. If the name is unknown, identify the speaker with a defining characteristic, such as:
[Male announcer]: To begin our journey...
(RABBIT #3 [hidden under the blankets]): Here I am!
- Sound effects should be included above dialogue and on a line alone: [POTS RATTLING] or (Crowd roars) or even [silence]
- Use objective adjectives to describe music (not subjective terms like "beautiful"): (DRUM BEATS) or [intense percussive music]. Include them above dialogue and on a line alone.
- Limit captions to two lines of text and break at natural, grammatical spots--i.e., don't split a proper name or break phrases up.
- Spell lingo, slang, and accented words phonetically if they're important to the meaning of the content (e.g., “y’all” instead of “you all”).
For an excellent in-depth guide to writing captions, see the BBC's Subtitle Guidelines.
If you don't have the time or resources to add captions to video yourself, there are many paid captioning services available. One of the best and least expensive is Rev. For $1 per minute, they will caption any video, usually in 24 hours. In some cases, it may make sense to take advantage of a paid service like Rev.
About transcripts and audio descriptions
At this time few video players support transcripts and audio descriptions, and they are not required for video on ASU web sites (only captions are required). However, as the technology catches up in the next few years, expect to see the ASU guidelines requiring either transcriptions and/or audio descriptions as well.
A transcript is a text version of the dialog in a video or audio recording. Transcriptions are helpful for users who are deaf, who speak English as a second language, or who are in a quiet (or loud) environment that precludes listening to the audio track. Like captions, transcripts typically are time-synced with the recording; unlike captions, they are displayed as a text document directly under the video. (Note: A transcript file can be uploaded to YouTube or Vimeo/Amara to be used to create captioning.)
An audio description is an additional narration track that provides a textual description of the action, characters and other visual content in a video, primarily for users who are blind or visually impaired. Typically, the audio description track is spoken during pauses in the dialog--that is, in between captions. This trailer from the film Frozen is a good example of audio descriptions.
How to test
- Ensure that all videos are captioned.
- Check that captions accurately convey the audio, including relevant background sounds.
Relevant W3C WAI documents
- WCAG 2.1 Guideline 1.2.2 Captions (Prerecorded): Captions are provided for all prerecorded audiocontent in synchronized media, except when the media is a media alternative for text and is clearly labeled as such.
- How to Meet WCAG 2.1 Guideline