How do I add captions to an empty captions file in My Media?

If a media file only includes audio that cannot be automatically captioned, for example, music, sound effects, or speech in a language that is not listed on the Kaltura ASR captioning services overview page (opens new window), an empty English auto-captions file will be generated.

If a media file only contains music or sound effects, the file's owner or someone with permission to edit it (co-editor) will need to edit the empty captions file to add the captions and timestamps.

If a media file has speech in a language that is not supported by Kaltura ASR, the captions request process supports some additional languages. For information, see:

If your media file has an auto-captions file that includes some automatically generated text, see How do I edit captions in My Media? (opens new window) for steps to edit it.

Note: For additional assistance with captioning, please reach out to the Captioning Team at [email protected]

Tip: You may give someone permission to edit captions on a file you own by following the steps to add them as a Co-Editor (opens new window).

Go to My Media.

Screenshot of link in menu.

Select My Media from your Global Navigation Menu.

Note: Steps for McIntire School of Commerce instructors to access McIntire My Media can be found in How can I access McIntire My Media? (opens new window).

Select the file to edit.

Screenshot example of My Media with a video file outlined.

In My Media, choose the video or audio file with the captions to edit by selecting its thumbnail or name.

Select Actions, then Edit.

Screenshot of the Actions drop-down menu.
  1. Scroll down on the page under the media player.
  2. Select the Actions menu.
  3. Select Edit.

Select the Captions tab.

Screenshot of the Captions tab.

Select the Edit Captions button.

Screenshot of the Edit Captions button.

Select the empty caption.

Screenshot of the Closed Captions Editor with the empty caption text field selected.

The empty captions file will display starting and ending timestamps of "00:00:00,000" and white space to the right of these timestamps.

Select the blank area to the right of the ending timestamp to open the text field where you can add the first caption.

Enter text for the caption.

Screenshot of text being entered in a caption's text field.

Enter text for the caption, keeping in mind the following:

  • A caption should remain on the screen long enough for it to be read, a minimum of 1 or 2 seconds, depending on how much text is included in the caption.
  • A single caption should not include more than 2 lines of text.
  • If the audio includes sung words, each caption's text should contain no more than 32-36 characters, including spaces.
  • When captioning a video file, a sentence may need to be broken into two or more captions to ensure the text does not cover up too much of the video's image.

Note: For additional information about creating captions, see the following resources:

If you have questions about captioning best practices or need assistance with creating captions, please reach out to the Captioning Team at [email protected]

Tip: If you would like to include musical note icons in your captions to denote music playing, you can copy one of the following icons:

  • ♪
  • ♫

Paste the icon into a caption's text field, for example: "♫ Smooth jazz music plays ♫"

Edit the caption's timestamps.

Screenshot illustrating the numbered steps below.

You will need to edit the caption's starting and ending timestamps to specify when the caption should display.

  1. Play the video or audio file to check when the caption should start and end.
  2. Edit the starting timestamp, if needed. A caption's starting timestamp should correspond to when a listener would begin hearing the related sound or words. If the sound could be heard at the start of the media file, you do not need to edit the "00:00:00,000" starting timestamp. Note: Timestamps are formatted as hours:minutes:seconds,milliseconds, where minutes and seconds are numbers between 00 and 59, while milliseconds are between 000 and 999. For example, a timestamp at 00:00:18,425 would be 18 seconds and 425 milliseconds after the start of the video.
  3. Edit the ending timestamp. A caption's ending timestamp should correspond to when a listener would stop hearing the sound. This timestamp should be a minimum of 1 or 2 seconds after the starting timestamp. If the audio includes singing, the maximum length of a caption should be 6 seconds after its starting timestamp.

Add a caption.

Screenshot of the Closed Captions Editor with the Add caption button outlined.
  1. Hover your mouse over the caption to make the Add caption button appear, then select this button.
  2. A copy of the caption will be created for you to edit, with "[COPY]" at the front of the line, for example: "[COPY] ♫ Smooth jazz music plays ♫"

Copy and paste the ending timestamp.

Screenshot illustrating a timestamp being copied and pasted.

The Closed Captions Editor will have set the ending timestamp of the new copied caption to the original caption's ending timestamp. This automatic copy process is intended to assist with splitting a caption that includes too much text into two lines of captions.

You will need to reapply the ending timestamp to the original caption as follows:

  1. Select and copy the ending timestamp from the caption that begins with "[COPY]".
  2. Paste the number into the previous caption's ending timestamp field.

Note: When the timing of two captions overlaps, it produces an error that will prevent the captions from displaying when the media file is played. A pink background color and red outline will appear on the ending timestamp field for the first caption and the starting timestamp field for the second caption until the timestamps are updated.

Edit the copied caption.

Screenshot illustrating a caption being edited.

Replace the text of the caption that begins with "[COPY]" with the new caption's text.

Edit the new caption's timestamps.

Screenshot illustrating the numbered steps below.
  1. Play the video or audio file to check when the new caption should start and end.
  2. Edit the starting timestamp. A caption's starting timestamp should correspond to when a listener would begin hearing the related sound or words. If the audio corresponding to the new caption could be heard immediately after the audio corresponding to the preceding caption, the new caption's starting timestamp can be the same as the preceding caption's ending timestamp. Note: Timestamps are formatted as hours:minutes:seconds,milliseconds, where minutes and seconds are numbers between 00 and 59, while milliseconds are between 000 and 999. For example, a timestamp at 00:00:18,425 would be 18 seconds and 425 milliseconds after the start of the video.
  3. Edit the ending timestamp. A caption's ending timestamp should correspond to when a listener would stop hearing the sound. This timestamp should be a minimum of 1 or 2 seconds after the starting timestamp. If the audio includes singing, the maximum length of a caption should be 6 seconds after its starting timestamp.

Add and edit captions and timestamps as needed.

Screenshot of Closed Captions Editor with captions added for an example video.

Repeat the steps to add and edit captions and timestamps until captions have been added for all the audio.

Select Save.

Screenshot of Closed Captions Editor with Save button outlined.

Scroll up near the top of the page and select Save.

Update the captions' accuracy percentage and save.

Screenshot of Confirm caption accuracy dialog.

A Confirm caption accuracy dialog will pop up.

  1. Use the slider to adjust the accuracy percentage of the file to the best of your knowledge.
  2. Select Save.

Note: If a captions file's accuracy percentage is less than 99%, UDOIT will warn that the captions may have been automatically generated and include errors. For information on using UDOIT to check course content for accessibility, see the help articles on UDOIT (opens new window).

Select Back.

Screenshot of Closed Captions Editor with Back link outlined.

Select the Back link near the top of the page to return to the video or audio file's editing page.

Edit the captions label.

It is recommended to remove the "[auto]" indicator from the captions label to let viewers know that the captions are accurate.

Select the Captions tab.

Screenshot of the Captions tab.

On the video or audio file's editing page, select the Captions tab.

Select Edit.

Screenshot of the caption properties table with the Edit button outlined.

A table listing the Language, Label (the text of the option in the media player to display captions), File type and Accuracy of the captions file will display, along with Actions, which includes buttons you can use to modify the captions file's properties.

Under Actions, select the pencil (Edit) button.

Edit the label.

Screenshot of the Edit captions window.

An Edit captions window will pop up.

  1. Edit the Label for the captions, for example, change it to English.
  2. Select Save.