Film-Tech Forum ARCHIVE: Subtitles

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Posted by Paul Willmott (Member # 3904) on 01-19-2015, 10:09 AM:

We use a Barco DP2k-15C and a GDC server SX2001A and are having problems with the subtitles on a film called Human Capital. They appear fine for the first 27 mins and then disappear only to re-appear around the hour mark. We have the subtitles generated by the server (we used to use cinecanvas on the projector but that seems to have stopped working). Any thoughts?

Paul

Posted by Steve Kraus (Member # 476) on 01-19-2015, 10:19 AM:

Are you sure the data is there? If you plug the drive the movie came on into a computer (capable of reading EXT2 formatted drives) you can see the various files that make up the DCP. Typically (but not always) a movie is broken down into reels like from the film days. So many files representing reels of picture; so many files representing reels of sound.

On the captioned version, from what I've seen there is usually an individual folder for each "reel" and inside that folder will be an .xml file with the actual caption text (as well as where and when to display them) and a .ttf file of font. Unlike the picture and sound files that are encrypted, the caption .xml files are directly readable.

I can't comment on projector / server issues but it might be helpful to know if you have the caption data for all the reels. Of course, being on the transport drive is no guaranty it was ingested but most likely.

Posted by Paul Willmott (Member # 3904) on 01-19-2015, 10:35 AM:

Good call. I've looked at the contents of the drive and there seems to be 9 reels but only 7 subtitle files! This is the second copy of the DCP we've had so I am wondering why no-one else has noticed this.

Paul

Posted by Leo Enticknap (Member # 534) on 01-19-2015, 11:52 AM:

I showed this as part of a "New Italian Cinema" season last fall (autumn). While I can't recall having had any problem with this particular DCP, I did have various issues with some of the others in the same shipment.

As a general rule, the lower the budget and more obscure the origin of a DCP, the more likely it is to have errors and glitches in it. Desktop computing has now evolved to the point at which it's possible to make DCPs from the typical rendered output that independent and low budget "film" makers end up with (high bitrate ProRes files, usually), and there are even free programs, e.g. OpenDCP and DCP-o-Matic, that will create them.

Most of the time these DCPs play without any problems, but the quality control isn't as reliable as if a professional post house does them, because a post house will typically test the DCP it has just made on most of the server models typically found in theaters before releasing it to the customer.

With the German, Spanish and Italian mini-seasons we ran last year, the most common problems were distribution drives formatted as HFS/HFS+ (the MacOS native format) and thus not being recognized by our server, and SMPTE subtitles not working on the DSS200 and series 1 projector combination in one of our houses.

My rule of thumb is that if a DCP comes from anywhere other than a big Hollywood studio, proceed with caution and test thoroughly in advance of showtime.

Posted by Carsten Kurz (Member # 5396) on 01-19-2015, 01:33 PM:

When it comes to subtitles, it is essential to have server and projector firmware as current as possible. There has been a ton of bugfixes over the last years to get subtitles more stable.

- Carsten

Posted by Stephan Shelley (Member # 8587) on 01-23-2015, 08:29 PM:

Leo

Make sure your TI software on there series 1 is 15.1. That adds SMPTE subtitle capabilities to it.

Posted by Peter Castle (Member # 1997) on 01-24-2015, 02:11 AM:

Several months ago I posted (in another thread) a concern about the location of OCAP titles on a scope image. At the time the suggestion was that the feature may have been poorly set up. Since then I've looked at a couple of other features ("Fury" and "Mockingjay Part 1") whose OCAP also had their descenders off the image. Is it possible that the positioning of the captions is not being translated for a 4K projector (NEC3240) - even though both those features were 4K? We have a GDC IMB. The loss of descenders is not a result of cropping of the scope image - when shown with flat settings, the descenders are in the black area below the image.

Posted by Carsten Kurz (Member # 5396) on 01-24-2015, 09:05 AM:

Common issue with IMBs and 4k/2k mixed systems/features. You need to setup your macros properly. Otherwise the scaling and position reference for subtitles is mixed up between 2k and 4k. Also happens on Dolbys.

Look e.g. here:

http://www.film-tech.com/ubb/f16/t001327.html

And yes, sometimes subtitle positions are simply set sharp. When using Doremis, you can use the server-side subtitle engine instead of the projector-internal TI subtitle engine. The Doremi subtitle engine has options to shift subtitles.

- Carsten

Posted by Paul Willmott (Member # 3904) on 01-29-2015, 06:04 AM:

Following on from last weeks film not showing subtitles on parts of the film, we had a similar error on another film from the same distributor (Stations Of The Cross). They are looking at it and we are looking to see if a GDC server update is available. My first thoughts about missing subtitle files proved wrong, although the reel numbers in each subtitle file were odd. On the first film reels 1 & 2 had no subtitles (which was correct) but reels 3-9 were labelled in the subtitle files as reels 1-7. On this week's film, all the subtitle files stated reel 1!

I've been trying to get the Barco to show the subtitles just to see if that works any better than the server generated ones but after having switched the server ones off and selected enable subtitles on the Barco, the Barco times out (I assume that it can't find the subtitles) with a big red light showing!

So at the moment I am pinning my hopes on a GDC server upgrade unless anyone else has some suggestions!

Posted by Antti Nayha (Member # 4980) on 02-01-2015, 06:46 AM:

Misnumbered subtitle reels seem to be fairly common, but I've never encountered any playback problems with Dolby or Doremi. I guess the subtitle reel numbering is more like an informational annotation, and the actual playback should always be done according to the CPL – regardless of the reel number data in the subtitle reels themselves. Similarly, the subtitle language data in the subtitle file doesn't seem to have any effect on anything.

I'm not saying it's good practice to misnumber anything, and of course it's possible that GDC is pickier in this regard. Thankfully our copy of Stations of the Cross had burnt-in subtitles. [thumbsup]

Posted by Marcel Birgelen (Member # 6801) on 02-01-2015, 08:20 AM:

quote: Leo Enticknap
My rule of thumb is that if a DCP comes from anywhere other than a big Hollywood studio, proceed with caution and test thoroughly in advance of showtime.

Also, ask them if they can burn-in subtitles if possible. Often they can, because those things are made-to-order anyway. Although I'm actually not in favor of hard-coded subtitles... But, given the amount of issues you can get with those largely untested amateur releases, I think it's the safest way to roll if at all possible.

Posted by Antti Nayha (Member # 4980) on 02-01-2015, 10:04 AM:

^ Agreed – especially with 25/30 fps material, which is SMPTE most of the time.

SMPTE subtitles are still less reliable than Cinecanvas subtitles, and 25fps Interop is a bit of an anomaly (even though it works just fine at least on Dolby DSS200/220).