Closed Caption formats - support for overlapping phrases I am looking to develop a tool for editing Closed Captions for MP3s.  It is mostly in support of YouTube music videos.  I've been looking over the Supported Caption File Formats in this YouTube page and the example they show is:

0:01:23.000,0:01:25.000
This text displays for two seconds starting
1 minute and 23 seconds into the video.

0:02:20.250,0:02:23.8
This text displays from 2 minutes and 20.25 seconds after the start
of the video until 2 minutes and 23.8 seconds after the start of the video.

0:03:14.159
This text displays beginning 3 minutes and 14.159 seconds
after the start of the video for an undefined length of time. 


It seems clear enough there, with the first line being start,end time, the blank line being a delimiter, and the rest indicating text and line breaks.  The last 'time' entry indicates a start time but no explicit end time - it is up to the software to define how to render it (any examples my software makes, will have an explicit start &amp; end time).  That is basically what is shown in the SubViewer (http:// en.wikipedia.org/wiki/SubViewer - link broken to reduce 3 links to maximum of 2) example at Wikipedia.

What neither page makes clear is whether the captions could effectively overlap.  E.G. a busy meeting, or songs with lead and back-up vocals.  An example of the latter is Johnny O'Keefe's - She's My Baby.

The BG vocals start 

1. Bom, bom, bom, BOM..


Continue that with 2 &amp; 3 (when you're on a good 'bom', roll with it..)

Then JO'K cuts in with ..

4a.                Short black hair..
4b. Bom, bom, bom, BOM..


Does the format specify/expect that all captions will be non-overlapping periods of time, like lines 1-3, or does it also support 'interleaved' text as with lines 4 a/b?
I tried this just a short while ago, and YouTube supports interleaving captions! You can even jumble the captions around in time. So the first caption could be the last one showing up in the video.

Just specify the starting time and the end time on all of the captions and they will show up during the time you specified.

Have a good time captioning! :)