Open Subtitle questions

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Open Subtitle questions

Post by Alex_Rappoport »

Hi I'm new to the software and am creating a DCP for a feature doc. I have several questions:

My source prores file* has embedded CEA608 English captions that I want to embed as OPTIONAL projected text in the DCP. My interpretation of the manual is that I select "open subtitles" from the "Use as" checkbox in "Timed Text" tab. Correct?

I also have an SRT caption file I could import separately (as a VF?) but since I only need an English texted version it would be preferable to keep it within the primary DCP.

*The source file I'm working from was output from FCPX, which only seems to be able to embed/share CEA608, even though it can read SRT just fine. So I duplicated the SRT as CEA608 in the timeline, then exported the movie with embedded captions. It looks and works great in Quicktime player, but even though DCPoMatic "sees" the CEA608 captions, it doesn't list CEA608 as a workable filet type in the manual. A concern.

Another question pertains to previewing how the subtitles will look in the DCPoMatic interface. I have not been able to get the "View" or "Fonts" buttons to be activated in the "Timed Text" pane. And this makes me wonder if I need to work from SRT file instead. Only "Appearance" button is enabled.

The main problem I see is that the two-line text is coming across as overlayed one on top of the other! And I can't seem to get the lines to separate using the scale or line spacing options. what's up with that? I can reposition and change the scale of the overlapped text lines but not separate them properly.

Last two: when I select "show subtitle area" I am surprised to see the default position set at upper left of frame! Is the position of the overlay locked in by DCPoMatic or can it not be (re)positioned as desired with the projection system? Is an X/Y offset always needed if you want the overlays to be lower center as typical of subtitles? And (if I can solve the overlapped lines of text first) is there a best practice scaling offset to use for theatrical projection, so that the text isn't too large on a big screen?

Would greatly appreciate any help. I need to deliver this to my distributor asap!
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Re: Open Subtitle questions

Post by carl »


I haven't explicitly added support for CEA608 captions in DCP-o-matic, so although it's possible they are "automatically" supported (because one of DCP-o-matic's dependant libraries supports them), it sounds (from what you describe) like there are problems.

If you can use SRT, I would suggest that - lots of people do so, and it is well supported by DCP-o-matic.

The other question is about "optional" subtitles. There is no "subtitles on/off" switch with a DCP projector. The best way to approach this instead is to make two DCPs:

Firstly, an "original version" (OV) which has picture and sound.

Secondly, a "version file" (VF) which refers to the OV and adds the subtitles.

Then you can deliver both DCPs to the cinema and they can choose which they play.

Making an OV is covered in the early sections of the manual.

Making a VF DCP is covered later.

Let us know how you get on!
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Re: Open Subtitle questions

Post by Carsten »

Yup. If there is a deadline, just add the SRT to the project, and let DCP-o-matic ignore the CEA608 captions. Create a textless OV, then create a VF that reuses video and audio and only adds the SRT file.
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