Captioning & description
Captions are meant to support people who are deaf or hard-of-hearing. They are different from subtitles, which are only meant to translate dialogue for viewers who speak a different language. Subtitles assume the audience can hear music, background sounds, or non-verbal content. Captions, by contrast, will include these sounds in addition to all dialogue. They will describe sound effects, the type of music playing, or if the speaker has an accent.
Captions have been shown to support the learning of students who speak English as an additional language, students with learning disabilities, and students who are new to a discipline and may be unfamiliar with unique terminology.
Automatic captions are generated using speech recognition technology powered by machine learning. Although the accuracy and efficiency of the technology is always improving, it does not offer 100% accuracy and requires significant editing. Automatic captions can be used as a starting point for developing accurate captions and transcripts.
Accurate captioning of at least 99% accuracy is the only way to ensure that people who are D/deaf or hard of hearing can understand audio content. Automatic captions should never be used as a substitute for captions or ASL interpreting.
There are two types of captioning: open and closed. Open or “hard” captions are permanently embedded in the video stream and cannot be turned off by the user. Closed captions contain the exact same text as open captions, although users have the ability to toggle them on or off using the video player.
There are different factors to consider when deciding between open or closed captioning, such as the target audience, where it’s being uploaded, what video player or platform, and accessibility features of the video player.
There are many tools available to approach captioning. Below are just a couple of recommended suggestions. If you want to try captioning videos yourself, we recommend checking out the following resources:
When recording to the Zoom Cloud, a transcript will automatically be generated in WebVTT format. While this isn't a compatible subtitle format for many media players, it can be converted into one that is, or it can be uploaded as an accompanying transcript.
Step 1: Edit the transcript for accuracy
Accurate captioning of at least a 99% accuracy is the only way to ensure that people who are D/deaf or hard of hearing can understand audio content. Automatic captions should never be used as a substitute for captions. However, it is much easier and timely to use an automated transcript as a starting point when creating accurate captions.
Under Cloud Recordings,, external link find your recording. Click on the Play thumbnail to open up the Zoom media player. Navigate to the Audio Transcript panel on the right and click the pencil icon next to the phrase you want to edit. You can adjust the speed of the video if it makes it easier to make corrections!
Step 2: Download recording and corrected audio transcript
If re-uploading your recording to Google Drive, Ryecast or any video hosting platform, you will need the movie and transcript file. Click on "Download" in the top right corner, or download the files individually from the previous screen. The Zoom recording and transcript will download as a .MP4 and .VTT file.
Step 3: Upload captioning file or text transcript
Closed captioning is preferred for people who rely on captioning to fully comprehend a video. However, you can also include a Google Doc or Microsoft Word attachment of the transcript.
Closed captions in Google Drive
- Double-click on the video in Google Drive to launch it.
- Here, you can add the .vtt file to the video for closed captions:
- Click on the three-dot icon at the top-right which will show “more actions.” and click “manage caption tracks.” This will open a new tab in your browser.
- Click the plus button beside “add new captions tracks” and add the VTT file.
- Close the browser tab to return to the video preview.
If you receive any captioning error messages, convert the VTT file into SRT format (third party tool)., external link
Transcripts are great as they can be annotated and are print friendly. Although, when it comes to watching videos, closed captioning is preferred. The transcript file is a VTT file containing timestamps. Use a subtitle to plain text converter (third party tool),, external link to make the VTT file readable and user friendly. If privacy is a concern, you can also open the VTT file in most modern text editors such as Notepad on a Windows PC or TextEdit on a Mac by right clicking and selecting "Open with". You can then copy and paste the transcript into Google Docs or Microsoft Word and include it as an attachment with your recording.
Similar to closed captioning on a video; live captioning is done live in real-time where a person listens in remotely over the internet (via Skype for example) or phone, and delivers the reproduced text instantaneously on a projected screen, TV or a user’s mobile device.
As stipulated by the Accessibility for Ontarians with Disabilities Act (AODA) and Web Content Accessibility Guidelines (WCAG 2.0) Level A standards: all videos or audio that will be posted on a public facing website must be captioned and/or transcribed. Videos or audio used in your course made by a third party must be captioned upon request.
If you have a student in your course who requires captioned media, please contact Library Accessibility Services as soon as possible. Library Accessibility Services will work with everyone involved to ensure access to course materials, including the student, instructor and Academic Accommodation Support.