Comments on: Attaching subtitles to HTML5 video

By: silvia

silvia — Tue, 23 Aug 2011 10:02:01 +0000

@Pantelis Sometimes it takes a long time waiting to get technology right.

By: Pantelis

Pantelis — Tue, 23 Aug 2011 09:22:48 +0000

Toyed a bit with subtitles in JS, myself, and came up with this
HTML5 Subtitles, Video Javascript, BubblesJS, Bubbles JS

it makes no use of the track tag though. Generally I am not overally pleased with the support of such features and track tag is only the tip of the iceberg in HTML5 Video. The fact that you need WebM, OGG, Mp4 ? CHECK. The fact that you cannot embed video in other pages without having links to the source etc (like youtube does)? CHECK. The fact that most native player don’t even have a “full screen” button? CHECK.

It just feels to half-baked and I hope the W3C comes up with a strong and complete standard soon. It’s 2011… and still video is a problem…

By: silvia

silvia — Tue, 11 Jan 2011 08:39:42 +0000

@Frank do you mean by “internal” those where the subtitles are part of the video and by “external” those where subtitles are in a separate file? If so, both actually have their advantages and disadvantages.

When “internal”, you author the subtitles/captions and encode them into the file and you are pretty sure to never lose them again (unless somebody decodes the file and rips them out). However, it is very difficult to make changes/corrections to such a file. Also, it is impossible to use the same file for different encodings (e.g. for a WebM and a Ogg and a MP4 file).

So, from a production POV, keeping the text separate to the media content is much easier. It is also more easily distributed. It can also be stored as text in a DB and extracted dynamically to a text file on a Web server. And if you are supporting 100 or more languages, you really do not want all of these subtitle tracks inside the video resource, but only make them available on the server.

So, overall, keeping subtitles external is actually a lot more flexible and scalable.

By: silvia

silvia — Tue, 11 Jan 2011 08:34:29 +0000

@jbdough I don’t know of any other subtitle editors that output ttml, no

By: Frank Lowney

Frank Lowney — Mon, 10 Jan 2011 19:35:09 +0000

I’ve generally stayed away from external subtitling preferring internal, track-based approaches for reasons of portability. I can see the benefit of external systems to highly automated processes that might use voice recognition to generate the transcript and subtitle code but that seems not to be well in hand at this point in history. Are there other, more tangible arguments in favor of external subtitles?

By: jbdough

jbdough — Mon, 10 Jan 2011 18:10:05 +0000

silvia – that is really elegant. To reacquaint myself with perl, I wrote a little script to parse the ttml output of SubtitleEditor to an EasyCaptions format. Now I want to do the same for your solution. Are you aware of any other subtitle editors that output ttml?

By: silvia

silvia — Sun, 09 Jan 2011 22:59:06 +0000

@jbdough I have something very similar to EasyCaptions, see http://www.annodex.net/~silvia/a11y_bcp/demo2_transcript.html

By: jbdough

jbdough — Sun, 09 Jan 2011 22:19:10 +0000

EasyCaptions should not be overlooked.
http://pipwerks.com/2010/06/07/for-your-reading-pleasure-easycaptions/

The uncompressed source javascript library is only 222 lines.
”
Introducing EasyCaptions: A simple system for adding captions and an interactive transcript to online videos. EasyCaptions uses progressive enhancement to provide the best possible experience for all visitors, regardless of their browser’s JavaScript, HTML5 or Flash support.
”
EasyCaptions is not a commercial offering. It requires a slightly different format than ttml xml.

By: HTML5 Video, Players and Captions « bill creswell – captioning the internet one video at a time

Wed, 16 Jun 2010 00:13:58 +0000

[...] Also: http://blog.gingertech.net/2008/12/12/attaching-subtitles-to-html5-video/ Categories: Accessibility & Equal Access, Technology Comments (0) Trackbacks (0) [...]

By: silvia

silvia — Sun, 13 Jun 2010 04:36:18 +0000

Frank, yes, totally agree on the usability aspect of this work – more than just accessibility!

As for the label element – that is a tag on externally referenced timed tracks, so goes beyond just tracks inside the video resource. But indeed these attributes exist to allow for the creation of a uniform JavaScript API independent if tracks are sourced from internal data or external files.