Kaltura automatically generates "machine captions" for every entry, but these are only about 70-80% accurate on average. We strongly recommend editing your video's captions to ensure their accuracy. There's no doubt, however, that editing captions can be extremely time-consuming. This article provides advice on how to edit captions and transcripts as expeditiously as possible.
Below are the steps we recommend you take when you want to edit captions for a Kaltura media entry. Use the links to jump down and learn more.
If you want to edit the words spoken in your video, we strongly recommend editing the transcript instead of the captions. Caption files are specifically formatted to tell a video player when a line or two of text should be visible on the screen. A transcript, however, is purely text without any time codes. Accordingly, it can be slightly more annoying to edit a caption file since you have to navigate your way around the timecodes in order to edit the text.
Editing the transcript has another benefit, related to the principles of Universal Design for Learning (an instructional design framework focused on universal accessibility rather than individual accommodation): particularly if you add paragraph breaks in your document, editing the transcript allows you to create a text version of your video. Depending on the content of your video, you could offer the edited transcript as an alternative to students who would prefer not to watch the video. The key point is that this document must have equivalent educational content to the video. It can't be better or worse to watch one or the other.
If you edit the transcript, you'll want to be familiar with the workflow for using Kaltura's "machine alignment" workflow.
Kaltura does offer a web-based caption editor and it does have a handful of handy features. Clicking on a caption, for example, will bring you to that point in the video player. Ultimately, however, we find it much easier to edit captions and transcripts using local software on your computer, such as WordPad or TextEdit. "Find and replace" functionality can come in handy for multiple instances of misspelled words, and editing a text document on your computer requires much less clicking than when editing on the web. And as anyone who uses a computer frequently knows, the more you have to switch back and forth between your mouse and keyboard, the slower a task generally is.
As we mentioned above, we recommend editing the transcript rather than the captions, but if you prefer to focus on the captions, check out our documentation on how to edit captions on your computer.
Playing a video more quickly or slowly can help 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 gear icon within the player, then clicking the "Speed" pull-down menu to select your desired playback rate. Consider lowering the speed of playback to make it easier to edit without having to pause as frequently, or speeding it up if the machine captions are often accurate (or if you're a crazy fast typist).
Unless you're a court transcriptionist, you probably can't always make your edits while the video is still playing. You may find yourself having to pause every so often. And if you're switching between applications, windows, or frames to have to pause your video, that will slow things down. Accordingly, if you have headphones, a keyboard, or any other device with a play/pause button that's easy for you to access, leverage them while editing your captions.
As mentioned above, editing captions can be extremely time-consuming. Is there anyone who can assist you? A grad student? Your TA? A student worker in your department? All you'd need to do is add them as a co-editor for your video and they can either edit the captions in Canvas or in MediaSpace. Read our tutorial on collaborators to learn more about adding co-editors to your videos.