Closed Captioning
Captions (sometimes called subtitles) provide text content to people over a video or live virtual classroom session. Captions are a text version of the speech and non-speech audio information needed to understand the content. They are synchronised with the audio and usually shown in a media player when users turn them on.
This page helps you understand and create captions and subtitles and how you might approach using these in a Blackboard Collaborate Ultra session or in a subsequent recording.
During live sessions a Closed Captioner can be designated via the Attendees pane. Closed Captioners have to type captions in real time, and as such ideally need to be a very fast (and accurate) typer or a stenotypist. Closed Captioners will have the same level of access as the role applied to them before they were designated as a captioner (ie. participant, presenter or moderator), plus the ability to write captions.
Once someone has been designated as a Closed Captioner, all attendees of the session will receive a banner at the top of the screen asking if they wish to access the captions now being produced. Attendees can also decide to access the captions later in the session, by ticking the “Display Closed Captions (when available)” box in the “My Settings” pane.
Captions will be captured if the session is recorded. Captions both in live sessions and in recordings can be resized by the viewer. These captions can be amended or altered post-event - See the “Collaborate Recordings” section below for details.
Multiple caption “streams” can also be entered (manually, simultaneously), which can allow for captions in multiple languages. Attendees may pick which stream they want to view.
Collaborate itself does not offer auto-captioning. However, if you share your entire computer screen in the session you can then utilise the auto-captioning features of other software and these will appear on screen. Supported software with auto captioning features:
- Auto Captioning in Google Slides
- Auto Captioning in PowerPoint.
- Live Captions in Chrome
These captions can’t be amended in real time or post-event in the resultant recording made.
Auto captioning systems generally vary in quality, but there are some things you can do to help improve them:
- Speak clearly and keep a steady pace; quick, whispered or mumbled speech is less likely to be picked up well
- Avoid blocking the space between your microphone and mouth eg. with gesticulations, or covering your mouth as you speak
- Be aware that technical or specialist language is less likely to be picked up correctly than normal day to day parlance; if you are recording your session do note that such terms will likely need to be manually amended post event - see the next section on Collaborate Recordings below.
After the session:
Recordings should have captions applied to help ensure they are in line with the EU Digital Accessibility Regulations. There are several options for you to do so, depending on whether you used live captions in the session or not.
If you did not use captions in the live session, you can also download your recording and upload to Kaltura and use Reach to machine caption your recording and share it on your Blackboard course as a Kaltura video. Find out more about how to download it and caption it in Kaltura here.
If you did not use captions in the live session, you can still add them manually post-event. Collaborate will accept .SRT or .VTT file types for captions. If you have a captioned file, you can upload it as follows:
- Locate your recording
- Click on the circular “Recording options” icon on the far right of the recording’s row and pick the option to “Add caption source”.

If you used the inbuilt closed captions features in your session and want to amend them:
- Locate your recording
- Click on the CC “closed caption options” icon on the far right of the recording’s row and pick the option to “Download captions”
- Locate the downloaded Captions file on your computer, amend it as desired in Notepad, Notepad++ or similar
- Return to your VLE site’s Collaborate “Recordings” area and locate the capture again
- Once again, click on the CC “closed caption options” icon on the far right of the recording’s row
- Pick the option to “Overwrite caption source” and upload your amended file.

See more on Blackboard's Help pages