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How to Request and Edit Captions in MediaSpace

Captions are required for all videos on the web, particularly in an educational context. Read below to find out how they work in MediaSpace.

Accurate captions are an essential component of making your videos accessible. While UCSD is fully committed to ensuring the accessibility of all educational content, the benefits of including captions extend beyond addressing the needs of students with disabilities. Given that learning preferences are a variety of continuums (rather than binary categories such as visual learner/aural learner), making captions available to students provides them with choice on how they consume educational content.

What are Captions?

Captions typically display at the bottom of a video player and contain a textual representation of all relevant audible information that occurs in a video. They're essential for viewers with auditory disabilities to be able to perceive the educational content of your video.

Captions are different than transcripts. Caption files are specially-formatted text documents that include timecodes that tell the player when a particular piece of text should be onscreen. A transcript is basically just the text with no timecodes, often presented in a large block with no paragraph breaks.

How Do Captions Work in Canvas / Kaltura?

Here are the main things you need to know:

  • All videos added to Kaltura after 13 June 2020 will automatically receive machine captions.
  • Machine captions are about 70-80% accurate on average. We recommend that you edit your captions to ensure they're accurate.
  • Captions can be edited within MediaSpace, or downloaded, edited in a text editor, and uploaded.
  • Videos that come to Kaltura as a result of our Zoom integration will ALSO have captions that Zoom has generated. You can edit either Kaltura's or Zoom's - up to you.
  • Our default media player in MediaSpace does not display captions by default.
  • Our default media player in MediaSpace includes a transcript widget below the player, though it is initially collapsed.

Note that we describe two different methods of editing your captions: in the Closed Caption Editor within MediaSpace or by downloading the captions, editing them in a text editor on your computer, and uploading them back to MediaSpace.

Whys, Requirements, Caveats

Why You Might Want to Request or Edit Your Captions

  • Requesting Captions
    • The video in question was added before 13 June 2020 and thus didn’t automatically request machine captions
  • Editing Captions
    • Your captions are required by law to be accurate
    • Machine captions are 70% accurate on average and thus likely have sections that aren’t helpful to students who prefer or need to view the captions

Prerequisites

  • Requesting Captions
    • A video for which you are the owner or co-editor
    • The video must not have an existing machine caption request
  • Editing Captions
    • A video for which you are the owner or co-editor
    • The video must have a completed machine caption request (i.e. they’re done processing)

Caveats

  • Requesting Captions
    • You’re requesting captions generated by a computer, so they’ll only be around 70% accurate
    • If you’re adding new videos to “My Media”, chances are you won’t need to use this feature
  • Editing Captions
    • You can add collaborators to your video to allow others to edit your captions (e.g. a TA or student worker)
    • You can’t edit the machine captions that come from Zoom; it’s best to just delete them
    • If you use the Closed Caption Editor within MediaSpace, you can lose your edits if you don’t save periodically
    • Editing captions is time-consuming - but necessary

How to Request Captions

If your video was added to “My Media” after 13 June 2020, it should automatically have machine captions requested and inserted. These instructions should be followed if you need a video captioned that was added before this date, or if you make significant enough edits to a video that new machine captions are needed. Note that you will need to delete the old machine captions before requesting new captions.

There are two places that you can request captions: when looking at your main list in “My Media,” and when you’re on the “Player Page,” where you watch the video. Use the list below to jump to your preferred method:

Method 1: Requesting Captions in “My Media”

You can request captions for videos when looking at your list of media in “My Media.” The advantage of this approach is that you can request captions for multiple videos at once.

  1. If you’re not already logged into MediaSpace, go to https://mediaspace.ucsd.edu, click “Guest” at the top right of the screen and select “Login.” Enter your active directory credentials. The screen will refresh and “Guest” at the top of the screen will be replaced with your name.
  2. Click your name at the top of the screen and select “My Media.”
  3. Locate the video to which you want to add captions, and click the checkbox on the left side of that video’s row (just to the left of the video thumbnail).
  4. Scroll to the top of the screen and click “Actions,” and select “Caption & Enrich.”
  5. On the screen that appears, ensure that the following settings are selected:
    • Service: Machine
    • Source Media Language: English
    • Feature: Captions

A screenshot of the appropriate caption request settings.

  1. Click “Submit.” You’ll see a notation with a blue background at the top of the screen that confirms that your request for captions has been received.

You won’t receive any confirmation after submitting that your captions have been added, but you CAN tell by clicking on the video within “My Media” and looking at the video. If your captions have been added, you’ll see a small “CC” icon in the play bar at the bottom of the video preview. You can also just play the video and see if the captions appear at the bottom of the screen during spoken words.

Method 2: Requesting Captions on the Player Page

The “player page” is the page you visit when you click on a video in “My Media.” It’s basically where you watch the video (without editing it). This method is pretty much the same as the one above, but from a different location.

  1. If you’re not already logged into MediaSpace, go to https://mediaspace.ucsd.edu, click “Guest” at the top right of the screen and select “Login.” Enter your active directory credentials. The screen will refresh and “Guest” at the top of the screen will be replaced with your name.
  2. Click your name at the top of the screen and select “My Media.”
  3. Locate the video to which you want to add captions, and click on the title or thumbnail. You’ll be brought to the player page.
  4. Below the video, click “Actions” and select “Caption & Enrich.”
A screenshot of the player page, with the "Actions" menu circled.
  1. On the screen that appears, ensure that the following settings are selected:
    • Service: Machine
    • Source Media Language: English
    • Feature: Captions
  2. Click “Submit.” You’ll see a notation with a blue background at the top of the screen that confirms that your request for captions has been received.

How to Edit Captions Using the Closed Caption Editor

You can edit your captions within MediaSpace using the Closed Caption Editor.

  1. If you’re not already logged into MediaSpace, go to https://mediaspace.ucsd.edu, click "Guest" at the top right of the screen and select "Login." Enter your active directory credentials. The screen will refresh and "Guest" at the top of the screen will be replaced with your name.
  2. Click your name at the top of the screen and select "My Media."
  3. Locate the video for which you want to edit captions, and click the pencil icon in its row.
  4. Click the "Captions" tab below the video preview.
  5. Click "Edit Captions." You'll be brought to the Closed Caption Editor.
A screenshot of the captions tab, with "edit captions" circled.
  1. Edit your captions. Read below to learn about the features of the Closed Caption Editor.

Closed Caption Editor Functions

  • Editing text: Click on any row within the editor to edit the caption. 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").
  • Editing timecodes: If you wish, you can click on either a start or end timecode to edit it, which changes when the particular caption is displayed onscreen. (Generally speaking, this is generally not recommended due to the risk of overlapping timecodes.)
  • Adding speaker names: If you have multiple speakers, it can aid some viewers by identifying them in the captions. You have the option of adding a speaker's name to the beginning of a caption line by clicking the checkbox next to a caption's row and entering their name in in the field labeled "Add Speaker to selected items."
  • Finding and replacing words: Use the field next to the magnifying glass to find terms in your captions, and use the "replace with" field to replace all instances of that word with what you enter. This feature can save you some time if you use complex terminology, acronyms, proper nouns, or any other spoken words that the machine captioning system is repeatedly getting wrong.

Note that the >> symbol indicates that the system has detected a new speaker. Be sure to delete it if the speaker hasn't changed or to add it if the speaker has changed.

An annotated screenshot of the closed caption editor and its functions.
  1. When you're done making your edits, be sure to click the "Save" button at the top right of the screen. Confirm that you want to save by clicking "Yes."

After saving your edited captions, your changes will be visible immediately in the player (and in the transcript widget).

Tip: Save Frequently

As mentioned above, we strongly recommend that you save your work frequently if you edit within the Closed Caption Editor. Your session may time out, and unless you've saved your edits, they may be lost.

How to Edit Captions on Your Computer

If you're working on a longer video (say, 30 minutes or more), it may be safer to download the captions onto your computer and edit them locally. Independent of the video's length, however, you may find this approach preferable to using the Closed Caption Editor in Canvas, given the various features of working on a text editor (using find and replace functionality, for example), and the comfort of knowing you always have a local copy of the captions.

Overview

Here's a quick summary of the steps involved:

  1. Download your captions from MediaSpace.
  2. Edit them in a text editor on your computer.
  3. Upload the file back into MediaSpace.
  4. Delete the old (inaccurate) caption file.
  5. Delete the Zoom captions (if applicable).
  6. Save your caption file someplace safe.

Instructions

  1. If you're not already logged into MediaSpace, go to https://mediaspace.ucsd.edu, click "Guest" at the top right of the screen and select "Login." Enter your active directory credentials. The screen will refresh and "Guest" at the top of the screen will be replaced with your name.
  2. Click your name at the top of the screen and select "My Media."
  3. Locate the video in question and click the pencil icon on its row.
  4. Click the "Captions" tab below the video preview.
  5. On the row with your captions, click the icon with the downward arrow, and the caption file will download to your computer. It will have an .srt extension.

A screenshot of the "captions" tab below the Edit Player.

  1. Open the .srt file with a basic text editor built into your computer (for example, WordPad on a Windows machine or TextEdit on a Mac).
  2. Now you can begin editing your captions. You can either download your video (we discuss how elsewhere) and play it locally, or play the video in your web browser.
A screenshot of captions in a text editor alongside a web browser with the Kaltura video player.

  1. Once you've made all of your edits, save your file and return to MediaSpace in your web browser.
  2. In the "Captions" tab under the Edit Player, click the button labeled "Upload captions file."
  3. Browse for the file on your computer, select the language, leave the accuracy at 100%, and give it a label. The label is what will appear in the caption selector in the player.
  4. It's likely you'll see at least two sets of captions at this point. Delete the old set of captions by clicking the "X" in its row (so inaccurate captions aren't an option in the player).

Your edited captions will be visible in the player immediately.

Caption Editing Tips

There's no doubt that editing your captions takes some time. Below are some tips about how to make the process as efficient as possible while ensuring accuracy and accessibility. Click any of the links below to jump to a more detailed explanation.

First review the captions without playing the video

Many of the errors that are made by machine captioning have to do with mistakenly assuming there's a new speaker, misspellings, and grammatical errors. These can be fixed without playing the video and won't have you constantly stopping and starting the video. If you were the one in the video, there's a good chance that you know what was said anyway.

Leverage media player speed controls

Playing a video more quickly or slowly can serve you well when you're editing your captions. The Kaltura video player, for example, offers you the ability to change the speed of the playback by clicking the "1x" button in the player controls. Consider lowering the speed of playback to make it easier to edit without having to pause as frequently. Alternatively, if you're finding the captions to be more accurate than expected, speed the video up.

Leverage peripheral devices with play/pause buttons

If you have headphones, a keyboard, or any other devices with a play/pause button, you can leverage those buttons to your advantage while editing your captions. That way you don't have to constantly switch back and forth between applications.

Be aware of speaker changes (or lack thereof)

At minimum, a change in speaker should be denoted with >> in the captions. Ideally, instead use square brackets and enter the speaker's name (e.g. [John Smith]). For whatever reason, machine captions often mistakenly detect a change in speaker, and as a result, your captions may be littered with >> characters. If there wasn't a change in speaker, delete the characters.

Pay for human captioning (optional)

Because you can upload captions yourself, you can leverage captioning services that you employ on your own, such as Rev.com or Cielo24. Captioning services like these usually cost between $1 and $2 per minute of media. (That is, a 5-minute video would cost between $5 and $10.) Take note, however, that all captions uploaded to Canvas must be in .srt format.

Frequently Asked Questions (FAQs)

Use the list below to jump to the answer.

What does the law say about captions? What are my responsibilities?

Answer: All of your videos must contain accurate captions.

There are two main components to this answer: first, that your videos must contain captions, and second, that they must be accurate. As stated above, all videos added to "My Media" after 13 June 2020 will automatically have captions requested and inserted into the video, so a good portion of the work is being done for you. Do note that instructors can also easily request that machine captions be added to video added to "My Media" before that date by following instructions in the relevant section above.

However, the captions that are added to Kaltura videos are "machine captions," which tend to be about 70% accurate for colloquial speech. Accordingly, it's your responsibility to review and edit the captions for accuracy, which is why we've included the instructions above. In addition, captions should include all auditory information relevant to the educational message. So if you play a piece of music that relates to the point you’re making, you should include a caption that describes the content as it pertains to the learning goals. For example:

[a few bars of a mournful funeral dirge]

Can another user edit my captions for me?

Answer: Yes, by giving them a "co-editor" collaborator role.

Follow our instructions on adding collaborators to a video to add a user as a "co-editor" on your video. The video will then show up that user's "My Media," after which time they can follow the instructions on this page to edit your captions. Note that that user will also be able to perform a variety of other edits to your video, such as renaming it, changing the description, changing the thumbnail, etc. They'll also be able to download your video.

What happens to my captions if I edit a video?

Answer: They will be cut appropriately, but you should review your captions around the edit points to ensure their accuracy. If you “save a copy” of your video, a new request for machine captions will be generated.

If you perform edits (cuts) on a video with captions, once the new video is done processing the captions should reflect the cuts as well. If you elected to "save a copy" of your video in the Video Editor (which we always recommend instead of just "save"), the new video generated will trim the existing captions appropriately, but a new machine caption request will also be submitted. So, eventually, your video will have at least two sets of captions - one old and one new. If you've edited the previous set of captions, you should just delete the new machine captions once they come in.

Can I get human-generated captions?

Answer: Yes, but you or your department will need to pay for it.

You aren't able to request human-generated captions within Mediaspace. But because you can upload captions yourself, you can leverage captioning services that you employ on your own, such as Rev.com or Cielo24. Captioning services like these typically just have you upload or link to media and usually cost between $1 and $2 per minute of media. (So a 5-minute video would cost between $5 and $10 for human-generated captions.) Take note, however, that all captions uploaded to Canvas must be in .srt format. There are many caption formats available, so be sure to request or download the one with an .srt extension.

The machine captions are quite inaccurate - can I just delete them?

Answer: Yes, but don’t.

You can delete any captions by going to the Edit Player (by clicking on the pencil icon when looking at the video in your list in "My Media"), clicking "Captions" below the player, and clicking the "X" on the line of the captions you want to delete. While we do recommend that you delete any captions that come automatically from Zoom (since they can't be edited), remember that all educational videos are required to have captions to abide by accessibility laws and guidelines.

Given that human-generated captions cost between $1 and $2 per minute of media, it's not financially feasible for the university to pay for them for all videos entering Kaltura. We've enabled machine-generated captions to provide a good faith step towards making all of our videos accessible, but the last step - ensuring their accuracy - is up to you.

Have additional questions about video? Contact Multimedia Services at kaltura@ucsd.edu.