You can download the subtitle file for a video (in .vtt format) and the transcription file (in .txt format) by following the instructions below.
From the Video Portal
You can download the existing subtitle file for a video on the Video Portal by clicking on the Options button under the video and selecting Download subtitles, as highlighted in the image below.
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From the embedded video player
Click the download icon on the player controls as shown in the image below, then choose the subtitle/transcription file as required.
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Editing the subtitle file
The original uploader of the video is able to replace the subtitles for the video by following the instructions mentioned in this FAQ page.
A VTT file can be opened in any text editor, such as Notepad on Windows, or Textedit on a Mac. The file will contain the timings and subtitle text to be displayed.
The transcription file does not need to be edited as it is automatically produced from the subtitles; so if a subtitle file is updated, the transcription file will also reflect those changes automatically.