DCP with Atmos for Cinema Release

[ToddHooge]

Hi Guys,

I was hoping to get some advice from you, as I have recently been contracted by a production company to up-mix an unreleased indie feature film from 5.1 to Atmos. The Director wants both the streaming version (for Netflix, Amazon, Crave etc) to be prepared at the same time as the theatrical release. I've been told by the folks at Dolby that in order to do the theatrical release, I will need to go through a facility with a Dolby certified room, as well as use their proprietary RMU for the final QC and print for the theatre version of the film.

Background: I have a full-featured Atmos studio with 7.1.4 here on Vancouver Island. I've mixed both music and post thus far, and have a number of projects out in the ether. I have the Dolby Atmos Mastering Suite with a separate RMU, and can mix the full compliment of the bed + 118 objects.

My question: Do you know if we actually need to go through certified Dolby facility to create the DCP (with Atmos) for the theatrical release? From what I can see, DoM handles Atmos just fine?... Once the DCP is created and provided, and it looks and sounds great, does anyone care if it went though a certified Dolby RMU or not?

This is a low-budget film, at around 400k, so everyone is looking to make things simple and as cost-effective as possible.

Any insights you have would be greatly appreciated.

Thank you,
Todd

[Carsten]

I hope anyone else can chime in here. First of all, ATMOS is a Dolby brand, and it may be that what they say is targeted at the brand rights, not towards the technical aspects. ATMOS was the first object based audio system for cinema, but there is now an official open standard that is compliant with ATMOS, Immersive Bitstream. So, you could do the same what you do in ATMOS, but call it immersive Bitstream and have no obligations to Dolby.

https://isdcf.com/papers/ISDCF-Doc15-IA ... 006012.pdf

It may be that at a time, as long as Dolby Equipment was the only one available for ATMOS playout, that Dolby was able to control the use of it's system by certificates. That is, only if the DCP had been authored with Dolby Equipment and received a Go from a Dolby technical assistant, was the DCP able to play on ATMOS systems. Now, that may have changed with the SMPTE immersive bitstream.

DCP-o-matic will only wrap the ATMOS/IAB AUX data file into the DCP, and will not touch any data within it. So, first step probabably for you would be to find out how to create a SMPTE Bitstream compatible AUX data file (MXF) and the necessary accompanying timecode.

I remember we had a few discussions on this forum recently covering ATMOS, and there were a few people with some experience participating. Search the forum for ATMOS, and you should find them.

Regards - Carsten

[jdent02]

My understanding is that the Dolby unit that they lease only to certified mix rooms is the only thing that can product ATMOS compliant MXF files for DCP usage. Unless someone managed to reverse engineer it.

EDIT: The only IAB creation tools I've found have been the IMF flavor that comes out of the Dolby RMU or Davinci Resolve Studio. I would assume these are not usable as-is in a DCP (as there is also a DCP IAB format), but I have no idea for sure. Resolve uses the Dolby ATMOS decoder for monitoring so I suppose their contract could forbid allowing DCP IAB files to be exported.

[gunnar]

My understanding is that the Dolby unit that they lease only to certified mix rooms is the only thing that can product ATMOS compliant MXF files for DCP usage. Unless someone managed to reverse engineer it.

Correct, if you are going to make Atmos for theatrical release you have to make the Atmos track on a Dolby RMU. And you will have to get someone from Dolby to come and certifie the studio.
In fact it is only the cinema Atmos that require that.
For a Blu-Ray and streaming Atmos you are good with the Dolby Atmos Production Suite in Pro Tools.

[Carsten]

Would be interesting to find non-Dolby licensed IAB encoding solutions. I guess Resolve will have one as soon as it is possible. For a low-cost product like Resolve, I am pretty sure they are not interested in paying much money for licenses.
The SMPTE IAB bitstream spec is out for a while now.

[jdent02]

I asked that very question in the Resolve forums.

The post is now buried on page 3 of their forum so I don't expect any more replies, but the one I got didn't answer the question at all.

Hopefully Resolve or Nuendo will get the ability to create generic IMB at some point. I'm sure there's not a whole lot of demand for the DCP version of object based audio since most everyone involved in that field already has Dolby or DTS-X equipment.

[igit]

in fact, to work with Dolby Atmos, you need a ready-made mxf from a sound studio with sound effects, as well as 5.1 or 7.1 sound - easydcp itself creates a control sync signal in channel 14. I can't tell you about the DOM. But I don't think there should be any problem with that.