Soft Subtitles

[eddyg]

Hi,

As you know we have existing SRT soft sub patches, however they have not been committed since the code is not pretty and only allows SRT into MP4.

What I'd like to propose is an abstract subtitle structure that follows the same fifo design as we are used to in HB. The subtitle buffers will contain a subtitle structure which may be text or an image. They are read in the usual fashion at the start of the pipeline and consumed where ever appropriate.

This will allow us to read subtitles in from existing files into an internal abstract format, allowing conversion between formats if we so desire.

Thoughts?

Cheers, Ed.

[eddyg]

As for the CLI interface, which I know was an issue before. I was thinking of something like:

--subtitle-import <filename1>,<filename2>,<filename3> --subtitle-offset <ms1>,<ms2>,<ms3>

Where we use the <filename> suffix of ".srt" to indicate an SRT file, allowing us to add support for other subtitle formats in the future, the optional "--subtitle-offset" is used to specify the time offset for the subs, since they rarely match the video.

Multiple subtitle tracks may be imported if desired.

In the GUI we allow selection of the subtitle file, and have an input for the offset, the preview can be used to trial it and get the sync right.

Cheers, Ed.

[jbrjake]

What I'd like to propose is an abstract subtitle structure that follows the same fifo design as we are used to in HB. The subtitle buffers will contain a subtitle structure which may be text or an image. They are read in the usual fashion at the start of the pipeline and consumed where ever appropriate.

This will allow us to read subtitles in from existing files into an internal abstract format, allowing conversion between formats if we so desire.

Thoughts?

So, basically what saintdev argued for when entropic first approached us with the SRT patch?

Sounds good to me.

[DrKitt]

This sounds like a pretty good direction to go in. I would assume support could then be further added for rendering Presentation Graphics out of mpeg transport streams? i.e. hd dvd and blu ray subtitles...

[Nemesis7]

Isn't possible to get an iTunes movie that has CC's in it and see how that track looks like? I have searched all over the Apple Dev site about a specification for the Subtitle Track, but couldn't find any. I can't imagine that the only effects one can apply are bold and italic effects, even the position of the subs seems fixed.

eddyg: could you or someone please provide me with a patched softsubtitle version of handbrake/mp4box ? Thanx!

P.S. I encode for my iPhone

[eddyg]

Isn't possible to get an iTunes movie that has CC's in it and see how that track looks like? I have searched all over the Apple Dev site about a specification for the Subtitle Track, but couldn't find any. I can't imagine that the only effects one can apply are bold and italic effects, even the position of the subs seems fixed.

eddyg: could you or someone please provide me with a patched softsubtitle version of handbrake/mp4box ? Thanx!

P.S. I encode for my iPhone

We know what it looks like - and how to do it - just haven't had time to implement it.

Cheers, Ed.

[Nemesis7]

Wow! Could you please provide me with an (Apple) Subtitle Track sample? I don't suppose it's the converted srt -> mp4 with the text changed to sbtl, right?

Btw do the Subtitle Tracks offer more effects than the ones I mentioned before? Maybe subtitle size that can be changed on the iPhone?

[Unkagar]

The only place you will find any kind of description of the text track for QuickTime specific subtitles is http://www.apple.com/quicktime/tutorial ... racks.html for fuller documentation of the descriptors used http://www.apple.com/quicktime/tutorial ... ptors.html. I personally have not found anything relating to closed captioning and how to implement it in a QT file.