Box Preview supports captions that have been embedded into video files - that is, single video file in which the caption/subtitle data has been embedded. There are two notable variants of this:
- The captions/subs exist as a separate text track in the video file.
- The captions are contained in the video stream/track. The data is tightly coupled with the actual video picture data (but can still be toggled on/off).
Box does not support captions/subtitles as separate files. If you have a video with a separate subtitle file (e.g. .srt), you will need to embed the subtitle file into your video file using one of the methods outlined below.
Note: This feature is only available to Business-Plus users or higher.
Enabling Subtitles/Closed Captions
When you preview a video file that includes a subtitle track/closed captioning, you will see a button marked CC in the preview window. Clicking this button will toggle captions on or off. If your video includes multiple subtitle/caption tracks for different languages, you can select a specific subtitle track by opening the Settings menu (Gear icon) and clicking Subtitles/CC. Select the appropriate subtitle track and subtitles will be displayed at the bottom of the screen.
Notes and Limitations:
- We do not yet honor positional and style cues. CC/Subtitles will be overlayed at the bottom of the video.
- CC/Subtitles do not yet show on mobile devices.
- This is only supported in our HD Video player. You must be at least in the Business-Plus tier to get HD video, and it is only supported on modern browsers (for IE11, only on Windows 8.1+).
How to prepare Box-supported Closed Captioned/Subtitled videos
|Software||Operating System||Requires Re-encode||Instructions||Output|
|YAMB||Windows||No||mp4 with MPEG-4 Timed Text track|
|MKVToolNix||Mac, Windows, Linux||No||mkv with SRT text track|
|Handbrake||Mac, Windows, Linux||Yes||mp4 with MPEG-4 Timed Text track|
|FFmpeg||Mac, Windows, Linux||No||
|mp4 with MPEG-4 Timed Text track|
There are also proprietary software options particularly for generating video with CEA-608/708 captions. These tools generally support more complicated workflows, and might make sense to use if you already have a workflow set up with them.