DCP VF: Soft Subtitle Color Misinterpretation - IMS3000

[denismartin]

Hello,

I have created a SMPTE DCP VF package with soft subtitles using easyDCP.
Due to an artistic choice, some subtitles appear in a specific shade of yellow. This color displays correctly in easyDCP Player and DCP-o-Matic Player. However, during a test screening at a cinema (with a Dolby IMS3000 server), the yellow appeared orange.
We conducted another test, changing the yellow colour from (FF)FFCC00 to (FF)FFFF00, and this time the colour was not misinterpreted.

Have you encountered a similar issue?
Is there a way to avoid color misinterpretation of soft subtitles—other than preparing an OV version with burn-in subtitles?

Thank you very much.

Best regards,
Denis

[Carsten]

Color misinterpretation for timed text and PNGs is still a common issue with DCI projection systems, unfortunately.

See page 7: https://www.isdcf.com/wp-content/upload ... POSTED.pdf


Do you have full technical access to the IMS3000 system? These systems support both projector- and serverside text rendering (yes I know the IMS3000 already sits within the projector). Changing between methods however is only allowed with admin login (and some knowledge how to do it without messing up other things).

[denismartin]

Hello Carsten,

Thank you for your response and the information.

It seems that the IMS3000 interprets colour codes in the XYZ colour space (someone mentioned this to me on another forum). When I ran some tests in DaVinci Resolve, using a "solid colour" background with the same yellow colour and applying a colour space transform, I got the same orange tone that my colleague saw in the cinema. As a result, we decided to change the colour to a safer yellow that remains consistent between RGB and XYZ. Unfortunately, I don’t have access to the projection system myself, as I’m in a different country from the film team, and the person in charge of the screening doesn’t have admin credentials.

Thank you.

Best regards,
Denis

[StephW999]

Bonjour Denismartin
https://www.projectionniste.net/forums/ ... 37#p148008
bien à toi.

[denismartin]

Bonjour StephW999,
Thank you so much for your test!
I hope that one day subtitle processing will be standardised, so there will be no differences between D-Cinema systems.
We had to choose a different shade of yellow, much safer (without any noticeable visual changes).
All the best,
Denis