Film-Tech Forum ARCHIVE: Beauty and the Beast Closed Captioning Issues (and SMPTE audio mapping)

This is topic Beauty and the Beast Closed Captioning Issues (and SMPTE audio mapping) in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Steve Guttag (Member # 268) on 03-17-2017, 11:49 AM:

So last night the complaints have been pouring in.

We, predominately, have USL Closed Caption systems...which have been pretty darn reliable for IOP features. However, with Beauty and the Beast, with encrypted subtitles, we have not been so lucky. Going into the "debug" screen of the web interface one can see where the device doesn't know when the next time in/out is and you will not have any captions. Updating the device to 160419 helps but is no guarantee of success. With 160419 AND if you reboot the UPC, THEN it likely will work.

I've had this problem on both Dolby and Doremi servers, thus far (going to check GDC soon but I suspect I'll find similar results)

In other news, relating to this title, the SMPTE channel mapping feature does not work on Doremi software, yet (at least not on the DCP2000/2K4) so again an issue where HI/VI were coming out of the rear surrounds.

Posted by Jason Metcalfe (Member # 5739) on 03-17-2017, 03:23 PM:

Thanks Steve, so is the issue with the UPC related to SMTPE vs. IOP channel mapping as well?

Posted by Jason Raftery (Member # 6291) on 03-17-2017, 03:38 PM:

I ran into trouble with encrypted closed captioning on the SMPTE release of How to Be Single last year with GDC and the USL system. The problem was on the GDC side and was fixed in subsequent software updates. I didn't have any complaints with Keeping Up with the Joneses (which was SMPTE / had encrypted captions) and have not had issues with Beauty & the Beast thus far. This is with GDC 8.01-build256 and 9.0-build397 (and later) with USL version 150725.

Posted by Steve Guttag (Member # 268) on 03-17-2017, 05:50 PM:

Just checked a site with a GDC server (SX2000AR) and USL captions and there were no problems there (GDC build 397 and USL 150725).

I also checked a site with GDC servers (SX2000AR) and Doremi Accesslinks and they are not having problems.

Posted by Carsten Kurz (Member # 5396) on 03-17-2017, 06:32 PM:

Steve - is that Doremi 2.64/on classic servers, or 2.8.11? I remember the pulled 2.8.11 had issues.

- Carsten

Posted by Monte L Fullmer (Member # 2797) on 03-17-2017, 06:52 PM:

We're good with our GDC SX3000 units and all of our USL - both the headsets units playing back both, the HI and DA tracks, along with the VI readers are picking up with the CCAP.

thx - Monte

Posted by Steve Guttag (Member # 268) on 03-18-2017, 09:25 AM:

DCP2K4 running 2.6.4-0 and whatever is current on the IMS1000s and IMS2000s

Posted by Harold Hallikainen (Member # 5405) on 03-18-2017, 11:42 PM:

I'd like to thank Steve for his help in diagnosing the problem. We've captured a couple days of logs out of the IRC-28C so I can see what's going wrong. Also, I'm working with a group through ISDCF to make captioning better.

Please let me know of any captioning issues. I want it to work perfectly.

Thanks!

Harold

Posted by Juan Jose Garcia Calvo (Member # 1702) on 03-19-2017, 07:14 AM:

I experience a problem with the Beauty and the Beast spanish VF dubbed version cpl:
I detected a little offset between sound and image. This is very dificult for me to say, but I think it's like sound appears in advance over the image.
Our server (the famous Datasat DC20) has the audio offset set at 0, and it can be chaged to positive numbers only (not negative) that I understand it make delay the image over the sound (the user manual says that this offset setting make delay sound over the image, but I think it's wrong, because if your cinema theatre is to large, you need to delay the image to make as sound is naturally delayed by the distance).

Well, if I change this setting to any positive value, the result is worse, so I set it to zero, as there is no negative values.

This only an issue of the Spanish version? It is my imagination?

Posted by Steve Guttag (Member # 268) on 03-19-2017, 07:36 AM:

One will need sound delay, never picture. In a series 1 projector, the image latency is about 3-frames. In a series 2 projector, it is about 2-frames. So even in a large auditorium, you will want sound delay.

Furthermore, your brain will always pick off sound before image because that never occurs in nature. It is MUCH more tolerant of sound after image (again, that occurs in nature all of the time due to how fast sound travels versus light).

Posted by Juan Jose Garcia Calvo (Member # 1702) on 03-23-2017, 07:40 AM:

I don't understand:

Naturally, if you project image and sound at the same time, the sound will arrive later to the viewer than the image, isn't it?

So, to compensate this, you have to "delay" the image as much as the sound is delayed naturally...

Posted by Marco Giustini (Member # 4544) on 03-23-2017, 09:17 AM:

As Steve pointed out, the electronics is faster at processing sound than picture. Hence, you'll always need sound delay even in larger auditoria.

Posted by Dave Macaulay (Member # 813) on 03-23-2017, 01:01 PM:

If the server sends out image and sound data exactly in sync, the projector electronics takes roughly 2 frames (1/12 second) decrypting (if it's an Enigma system) and translating the image data to DMD data. So during playback, the image on screen is about 2 frames behind the server output data stream.
The audio digital-analog conversion also takes some time but it's a lot simpler and takes much less time.
There's no set "sync" offset like with film optical analog or digital audio tracks. You can guess fairly close but different projectors and D/As have different latency times. Use a sync check track and do it by eye or instrument. As said, sound before image is much more obvious: set the delay for a just-noticeable sound lead then delay it until it seems right. It's much harder to get sync exact by eye approaching from "sound after image".

Posted by Juan Jose Garcia Calvo (Member # 1702) on 03-24-2017, 05:57 AM:

I understand it now.
Natural audio delay thanks to the cinema size (sound travel speed) is unnapreciable compared to the delay in the image produced by the projector's electronics, and that's why you ever need to delay sound to compensate it.

Where can I get this "sync check track"? I have no instrument to see, but maybe I can check it manually.

But it's strange that I noticed this "sound in advance" issue only with "Beauty and the Beast" Spanish release...

Posted by Dave Macaulay (Member # 813) on 03-25-2017, 12:04 PM:

I got a test track from freedcp.net but it has gone dead. I don't know if test dcps are available freely anywhere now...
There are non-dcp clips not hard to find like http://www.sync-one2.co.uk/support/test-files/ but they need to be converted to dcp.