As an author, you can generate or upload caption files to a video or audio file that you own in Arc. The most common file type is an SRT file, though Arc also supports VTT files, which are more user-friendly for mobile devices.
If you need help creating a captioned file, you can use a captioning site such as Amara to easily create captions for your video or audio files.
To automatically generate captions for your media, choose the spoken language  and click the Request button .
After your caption file has been queued and processed, your generated caption file will appear in the Manage Captions section.
View Captions Options
To view more options for the caption file, click the Options icon . To review and publish the captions, click the Edit link . You can also download , replace , or delete  any caption file.
To upload a caption file, click the language button for the file you want to upload.
Your uploaded caption will appear in the Manage Captions section .
To upload a caption file in a new language, click the button for that language .
To toggle captions, click the Captions icon . By default, captions are off.
To turn on captions, click the name of language you want to display .