Here at Cinevee, we’ve been hard at work adding support for closed captions and subtitles to our streaming video. Here’s what you need to know.
Captions vs Subtitles
Closed Captions and Subtitles are similar from a technology point of view. Both require displaying text over the top of a video, timed to match the video content. A typical subtitle or caption element has a beginning time, an ending time, and the information that should be displayed during that time.
Although the technology is similar, captions and subtitles are intended for different audiences. Closed Captions help people who can not hear the audio for a video. Closed Captions usually have extra descriptions in the text for actions or music in addition to dialog. Subtitles, on the other hand, are meant to translate content into different languages.
It’s the Law
The FCC has recently announced requirements for closed captions on video delivered on the internet. Depending on where your film is coming from, you’ll need to add closed captions by a specific date. Here’s the excerpt:
FCC rule 47 C.F.R. § 79.4(b):
Requirements for closed captioning of Internet protocol-delivered video programming. All nonexempt full-length video programming delivered using Internet protocol must be provided with closed captions if the programming is published or exhibited on television in the United States with captions on or after the following dates:
(1) September 30, 2012, for all prerecorded programming that is not edited for Internet distribution, unless it is subject to paragraph (b)(4) below.
(2) March 30, 2013, for all live and near-live programming, unless it is subject to paragraph (b)(4) below.
(3) September 30, 2013, for all prerecorded programming that is edited for Internet distribution, unless it is subject to paragraph (b)(4) below.
(4) All programming that is already in the video programming distributor’s or provider’s library before it is shown on television with captions must be captioned within 45 days after the date it is shown on television with captions on or after March 30, 2014 and before March 30, 2015. Such programming must be captioned within 30 days after the date it is shown on television with captions on or after March 30, 2015 and before March 30, 2016. Such programming must be captioned within 15 days after the date it is shown on television with captions on or after March 30, 2016.
Adding Closed Captions or Subtitles to Your Film
At Cinevee, the current file format we use for closed captions or subtitles is a DFXP file. This is an XML file that has one or more languages of timed text information inside. To add captions or subtitles, you’ll want to prepare this file before you upload your film. Once you have the video and the DFXP file, you can use our new interface to upload them to Cinevee. We’ll take both files and combine them so that customers can see your captions and subtitles when they play videos on the web or their mobile device.
If you want to add captions or subtitles to an existing film on Cinevee, you can upload the DFXP file and your captions or subtitles will be instantly available in the Flash video player. Right now, you would need to re-upload your film to have those captions available in the iOS player as well, as iOS captions are embedded with the video data.
Subtitles in Multiple Languages
If you would like to add multiple languages of subtitles to your video, simply upload a single DFXP file that has the languages included. Our Flash video player will give viewers the option to select which language of subtitles they want to see.
Currently, our encoding workflow does not support multiple languages for iOS playback. We are hoping to add this in the near future. Right now, iOS viewers will only see the first language in the DFXP file.
As of this writing, there are about 10 standards for closed caption and subtitles in video. Some use information embedded in the digital video data, while others reference an external file. We chose DFXP as our first supported format because of the multi-language support and because it is an external file that can usually be attached to a video without re-encoding.
Hopefully closed caption and subtitle formats will coalesce into one standard format in the near future. The WebVTT standard looks promising. Right now, 10 standards means there is no standard. As the closed caption and subtitle technology improves, Cinevee will be there finding the easiest way to make it work for filmmakers.