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Manage resources with Kaltura MediaSpace guide

Explore the features of City's media delivery platform and how to share your video content externally.

About Kaltura Reach captions

From Sunday 27 September 2020, videos uploaded to Kaltura MediaSpace, via the web interface or from within Moodle, will have computer-generated captions added automatically.

These automated captions are about 70-85% accurate (Kaltura, 2018). The accuracy of the machine-generated captions will depend on variables such as:

  • the clarity of the original recording
  • the accent of the presenter(s)
  • any specialist vocabulary used.

After Kaltura generates the captions, you should use the in-built caption editor to edit and correct them before you publish the video.

This caption file allows captions to be displayed on your video, and it also produces a transcript from the text for viewers to download.

Related guidance

Hide captions while editing

  1. Log in to
  2. Select My Media.
  3. Navigate to the relevant video.
  4. Select the Edit icon shaped like a pencil to the right of the video.

  5. Once the video has loaded, select the Captions tab underneath the video.
  6. Select the screen icon next to your caption file entry to hide the captions.
    • A screen with a bar through it shows that captions are currently hidden.
    • A screen icon shows that the captions are currently visible.

Remember to make your captions visible when you have finished editing them.

Open caption editor

  1. Log in to
  2. Select My Media.
  3. Locate and open the video for which you want to edit captions.
  4. From the ACTIONS menu, select Caption & Enrich
  5. Choose the Edit icon shaped like a pencil next to the captions file to open the editor

Edit captions

Kaltura Reach captions are machine generated. They are less accurate if the clip contains specialist vocabulary, strong accents or if the sound quality is poor. 

  1. Select the Edit icon shaped like a pencil alongside the captions.
    • The status needs to be at Completed before you can edit the captions

​​​​​​​Edit pencil highlighted alongside completed captions

  1. A new screen will load with the Captions Editor.

You can watch the the clip with the captions, and press pause each time you want to edit a caption.

Alternatively, you can scroll through the captions without watching the clip. If you need to check the video soundtrack, select the caption. The video will jump to that point and then select play.

Select the text of any caption to start editing.

Ensure you are constantly saving the changes you make by pressing the Save button in the top right hand corner of your screen. Kaltura Reach does not save your changes automatically and can also time out after periods of inactivity. 

Search and replace words

Use the Kaltura's Replace function to correct any repeated errors.

  1. Select Replace above the captions
  2. Type the original word in the Find Match box.
  3. Type your replacement word in Replace with box.
  4. Select the blue Replace button

caption Noodle being replaced with word Moodle

Identify a speaker

You can add the name of the speaker to selected captions.

  1. Tick the box to the left of each caption to which you want to add the speaker name.
  2. Above the captions, select Add Speaker and add the name as you want it to appear in the captions
  3. Select the blue Add Speaker button beneath the name field
  4. Reach will add the name in square brackets e.g. [Presenter]

Split captions

  1. Select the plus icon between captions.
  2. The editor creates a new caption which contains the same text as the original caption. The duration of the original caption is split between the original and new caption.

Delete a caption

  1. Check the box to the left of the caption.
  2. Select the Trash icon shaped like a rubbish bin.

  1. Kaltura will display a confirmation window ensuring you do want to delete that caption line. 
    • This deletion is irreversible

  1. You may need to adjust the timecodes on either side of the deleted caption if you don't want a gap between captions.


From the top right of the caption editor page:

  1. To save your edits, select Save.
  2. If you want to undo your edits, select Revert.

Publish captions

Once you have completed editing your caption file and saved it, return to your video on MediaSpace.

  1. Open the Actions menu beneath the video and select Edit.
  2. Select the Captions tab to edit the information related to your caption file.

Make captions file default

If you have more than one caption file attached to a clip, you can choose which file will play as default by selecting the tick alongside the relevant captioning file

Edit captions file name

You can change the name of the file as it appears when users select the CC button on the video player.

To edit the name of the caption file, select the edit (pencil) icon.

Delete captions file

To delete the caption file, select the delete (x) icon.

Download captions file

You can download your caption file. Select the download icon under the Captions tab. You can open the file as a text file in Notepad. When viewed as a TXT file, you will see the text of the captions and the timecodes.

You can save the file as an SRT file. The SRT format is a standard caption format that can be uploaded to other platforms.

Make the caption file unavailable

Select the screen icon to make the captions unavailable without deleting the file. When viewed in the player, the captions will be unavailable.

Upload a captions file to your video

You can upload a captions file to your video by either downloading a file from another video or creating one yourself.

You may wish to do this if you have previously-corrected your captions on an older video, but have had to make a small edit to it (without changing the timecodes) and subsequently uploaded a new copy of the video.

We recommend saving your caption files as either .SRT or .VTT files.

If you have downloaded your caption file from another MediaSpace video, it will be a .SRT file by default.

  1. Open the Actions menu beneath the video and select Edit.
  2. Select the Captions tab to see all current information related to your video's captions.
  3. Select the teal Upload captions file button on the right side of the screen

  1. Navigate to your captions file on your device select Open.
  2. In the overlay, choose the captions' language from the dropdown menu
  3. Select the accuracy (100% if you have fully corrected them already)
  4. Add a clear label for your captions (eg British English)
  5. Select Save

Ensure you hide or delete any other captions files on the video using the guidance above to avoid confusion for your viewers.

Request caption correction

You can request caption correction for MediaSpace videos on the IT Self Service Portal.

You will need to provide the following information to help the team process your request.

  • Links to videos (must be hosted on MediaSpace)
  • Confirm your videos are set as Unlisted
  • Note any important deadlines (please note that we cannot guarantee any dates of delivery).

Censorship and profanity in Automated Speech Recognition

Automated speech recognition can be inaccurate. Captions or transcripts of your recordings may contain words incorrectly transcribed as profanities e.g. swear words or inappropriate words. Alternatively, you might find that the captions or transcripts on your recordings are censoring words with a row of asterisks which means that students relying on captions are missing key information.

LEaD are gathering information on the impact of profanities and censorship in recordings. If you find any examples, please raise a ticket with us via the LEaD General Request Form on IT Self Service Portal. 

Please include as much information as possible, including system used - Lecture Capture, Teams, Zoom, links to the recordings on Moodle and timecodes.  

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