Warning from EasyDCP: "MCASubDescriptors"

[JianZ]

Hi there! I made a DCP and sent it to our distributor. They had no problems playing it; no interruption or anything, except EasyDCP gave them some warnings. Only info was: "Unknown element: MCASubDescriptors"

Does anyone know what this means? I'm a little green in this, but here's some info:
- macOS Monterey (Mac Studio 2022) M1 Max
- Used a ProRes422HQ for the DCP, combined with a 5.1 mix
- Feature SMPTE, 25FPS

Before creating the DCP, it gave me a warning that DCP set as 'Feature' + as ´SMPTE' needs to have markers in the first frame of credit. Could that be it?

[carl]

Hi,

We've had reports of this before. It appears that some influential companies are often only "recognising" a subset of the SMPTE DCP standards, and this MCASubDescriptors tag is not in that subset.

It's discussed a little in the Deluxe DCP guidelines on page 20.

It would appear that, unfortunately, DCP-o-matic should stop writing this tag, or at least have an option to remove it.

[carl]

I made a bug report in the tracker and I hope to get to it soon!

[StephW999]

Bv2.1 = MCASubDescriptors included in CPL CompositionMetadataAsset
(mxf file must be wrappred with mca descriptors (Soundfield and Audio Channel Labels Sub Descriptor, and channel configuration 4 , channel assignement 060e2b34.0401010b.04020210.03010400)
Use a mimima Asdcplib 2.10.31 and use 8 or 16 channels if possible. Even for 5.1 use silences for channels 7 and 8
however DCP o matic works perfectly, and comes as close as possible to the Bv2.1 standards
Let's leave the tags in the cpls
The version of easy DCP used by JianZ must be old

[carl]

I see what you are saying, but unfortunately I suspect this is not JianZ's old copy of EasyDCP but rather the distributor's... and quite often it seems that the next thing the distributor says is "we can't distribute this DCP as-is but we can fix it for you, just give us a lot of $$$ and we can make it all go away".

I'm not saying that this is what JianZ is experiencing but it does happen quite often, as far as I can see.

[barber]

How about a drop-down list in the settings where one could choose the SMPTE "flavor"? The "A" flavor could be the default and the user could switch to Bv2.1.

[carl]

That's more or less what I was considering, except I feel like it should probably go into advanced prefs or somewhere since it's not something that's reasonable to expect 99% of users to understand.

[Carsten]

Hi Carl - there is a more recent version of Deluxe's guidelines:

https://hpaonline.com/wp-content/upload ... 0314-2.pdf


In JianZ's case, it may indeed be that the distributor uses an outdated version of EasyDCP to qc incoming content.

[carl]

Thanks Carsten, good point - I'd forgotten that. They do now seem to more-or-less require Bv2.1. I'm not sure if it's worth trying to fight these old EasyDCP versions though. "Distributors" using "professional software" always seem to get a free pass.