Edit Captions on the Web for a Kaltura Video


All videos that Kaltura ingests are automatically given "machine captions": captions generated by a computer program that provide generally no less than 70% accuracy. Kaltura users can edit these or any captions attached to an entry. 

These instructions apply to all Kaltura users at UCSD with active directory credentials (instructors, students, staff, ec.). 

Captions can be edited in both Canvas and MediaSpace. Note that while this tutorial will walk you through how to use Kaltura's web-based editor, you can also download your captions and edit them on your computer.

Critical Concepts

What are Captions?

Captions are the textual representation of spoken dialogue, narration, or relevant audio information that display onscreen during a video. While their primary purpose is to make the video more accessible to viewers that may have difficulty hearing, captions benefit many viewers and address a wide variety of learning styles.

Though captions can be "burned into" a video during postproduction (that is, edited directly into the video, rendering them unremovable), generally captions are contained within a separate text file that's formatted in a particular way. Timecodes within the file tell the player when to display the text on screen.

Captions are technically different from transcripts. The latter typically refers to a raw text file just containing the text without any timecodes.

Things to Keep in Mind

Steps to Take

You can edit your captions on the web in both Canvas and MediaSpace. In either case, you'll need to get to "My Media."

In CanvasIn MediaSpace
  1. Log into Canvas.
    1. Go to https://canvas.ucsd.edu
    2. Enter your active directory credentials.
  2. Within Canvas, click My Media in the left navigation.
  1. Log into MediaSpace.
    1. Go to https://mediaspace.ucsd.edu
    2. Click the profile icon at the top right of the page and select Login.
    3. Enter your active directory credentials.
  2. Click the profile icon again and select My Media.
  1. Locate the video whose captions you want to edit, and click the pencil icon in its row.
  2. Click Captions below the video preview.
  3. Click Edit Captions. You'll be brought to the Closed Caption Editor.
  4. Edit your captions. View the information below to learn more about the various actions you can perform.
    1. Switch between caption files: use the pull-down menu at the top left of the page to select which set of captions you want to edit. If you don't have more than one set of captions, you won't have any options besides the captions you're currently editing.
    2. Edit caption metadata: Click Edit details to change the language, accuracy percentage, or label. The label is what viewers see when they see caption options within the media player. If you're editing the machine captions, you may want to change the label from "English (auto-generated)" to just "English."
    3. Find words: Use the field with the magnifying glass to find terms in your captions. Type in a term and press ENTER on your keyboard. All the caption entries that contain the term will be highlighted in yellow.
    4. Replace words: Click Replace to perform a find-and-replace action in your captions. This feature can save you some time if you use terms that the machine captioning system is repeatedly identifying incorrectly. Be aware that when you perform a replacement, it will replace ALL instances of the word - you won't be able to step through each instance and approve/reject the replacement. You may want to search for the term and see all its instances before performing the bulk replacement.
    5. Add speaker names: Particularly if you have multiple speakers, it can help some viewers by identifying them in the captions. To add a speaker's name to a line in your captions, click the checkbox on all the rows of captions where you want to add a speaker and click Add speaker. Type the name of the speaker in the dialogue box that appears and click Add speaker. Note that if your entry is the result of the Zoom integration, the speaker's name will already be in the captions.
    6. Autoscroll through the captions: If the Autoscroll switch is turned on (blue), then the captions will scroll down as you play the video. It will also move to the correct caption line if you skip around in the video using the scrubber within the player.
    7. Edit timecodes: If you wish, you can click on either a start or end timecode to edit it, which changes when (or how long) the particular caption is displayed onscreen. Generally speaking, this is generally not recommended due to the risk of overlapping your timecodes.
    8. Edit text: Click on any row of captions within the editor to edit the text. When a row is clicked on, the video preview on the right side of the screen will jump to that part of the video. If you play the video preview, the captions will scroll automatically (unless you un-check the checkbox for "autoscroll").
    9. Insert a new caption: Move your mouse between any of the caption rows and a button labeled + Add Caption will appear. Click it and you'll be able to insert a caption between the two existing captions. The timecodes will automatically be set to be between the end time of the previous caption and the start time of the following caption.
  5. When you're done editing your captions, click Save at the top of the page.

A screenshot indicating different buttons on the closed caption editor.

  1. Confirm you want to save your edits by clicking Yes.
  2. Click Back at the top right of the page to return to the edit page. 

Your edits will be reflected immediately in both the captions as well as the transcript. 

If you still have questions or need additional assistance, feel free to contact us at kaltura@ucsd.edu.