Hocus Pocus DCP

[Mark Strube]

I have Hocus Pocus starting a few weeks from now. However, the DCP ingest letter doesn't make sense to me. It states the runtime as 1 hour and 16 minutes. Yet, everywhere else I look including IMDB, Google, Wikipedia, etc. states the runtime as 1 hour and 36 minutes.

Could this be incorrect information on the ingest letter? Or are we receiving an edited version of the film? I'm curious if anyone might have some insight, since this affects our scheduling.

It's also unfortunate that they're sending us a 2.0 audio version, when a 5.1 mix has been available ever since the 2012 Blu-ray release.

[Frank Cox]

If I were you I'd send an email to the Disney booker and ask what's what.

[Mark Strube]

I will this week, but I figure posting it here might help others who also have this booked.

[Frank Cox]

It's definitely worth posting what you find out.

[Mike Blakesley]

Frank - are you on satellite delivery? If you are, there's probably no reason we shouldn't be!

[Frank Cox]

No satellite here. Still hoofin' the hard drives around, doing my part to keep Purolator Courier in business.

[Mike Babb]

Mark, if your Ovation has the DTS license, it's possible you can run 2.0 through the upmixer. If it's indeed LtRt on those two tracks you will get a decode 5.1. If it's dual mono, it will come out of the center channel, so not as desirable. Drop me a line if you like.

[Mark Strube]

Thanks Mike! I will be in touch as I've been wondering how to enable upmixing for certain DCP sources.

Ryan from Deluxe actually saw my post here and sent the updated ingest letter. Pretty cool!

[Mike Babb]

I think the suggestion to upmix DCPs actually came from Steve Guttag here on F/T, it will work for any incoming 2 channel source, analog or digital.

[Pete Naples]

Upmixing is something those of us who deal with festival screenings need quite regularly.

It works very well on the Ovation.

[Marcel Birgelen]

Upmixing DCPs from 2.0 stereo to 5.1 or 7.1 needs some software that actually does the upmixing for you. Most cinema audio processors currently don't offer real-time upmixing capabilities.

I've up-mixed stuff in the past using Pro Tools and DTS Neural, which uses some quite advanced algorithms to do the up-mixing. This is not entirely perfect, but with some tweaking, the results can be pretty convincing.

[Steve Guttag]

Marcel, which cinema processors don't offer a "Pro-Logic" type decode in real time? From Dolby, CP750, CP850, CP950 do. I would presume the AP20/AP25 can, the JSD60 sort of can (it can do it but it can only do it on pair 4 so some rewiring is needed to use it). Ovation can do it. Obviously, Q-SYS can. I'm pretty sure that the DPM series can from QSC to do it. That said, the place for it is really on the mastering side and DCP O Matic and do a good-enough job on things like Ads though probably not the best way to upmix a feature soundtrack.

[Marcel Birgelen]

Yeah, you're right... mostly at least.

It depends on what's in this 2.0 package... If it's true 2.0 sound, with none of the matrix-encoded channels in there, "Pro-Logic" will only create a "phantom center" speaker, but there should be no surround sound, other than maybe the occasional leakage, where the matrix decoding goes wrong. I don't know if I'd really call this upmixing though...

But there is Pro-Logic II and this is supported by the CP750, CP850 and presumably also on the CP950 and Pro-Logic II can do some basic upmixing. It's by far not as good as the far newer DTS Neural, especially not if it can work with "off-line files", where it can do some multi-pass "magic" (as in, it can learn from "the future").

For the AP20 and AP25 there is no Pro-Logic II support, at least I've never encountered it, but there is DTS Neo:6, which is the precursor of DTS Neural and which can also upmix to 5.1 and 7.1 from 2.0 sources in real-time. My experience with both types of upmixing is too limited to say which one is best (they both fade incomparison to DTS Neural though), but Neo:6 is the more recent incarnation and probably the more advanced one.

[Steve Guttag]

Marcel, I'm mostly concerned with a L/R 2.0 track coming out straight left/right. They sound really, really bad in a cinema where those speakers are really far apart. Whomever mixed their sound to a 2-channel master NEVER did so in a cinema environment with speakers 30-80-feet apart. Technically, a "phantom center" is just that, with level and phasing so good, the sound is perceived to come from a speaker that isn't there. Pro-Logic steers the sound to the center. To me, this is FAR preferable to just Left/Right and, somewhat, will be more faithful to a near-field 2-channel monitor than what happens in cinemas. Heck, I've seen DCPs of Mono movies where they just took the video master and put the "center" channel on Left and Right only.

I don't see true Lt/Rt mixes come through to DCPs so much. I have little interest in faking a 7.1 from a 2.0. I'm mostly trying to get center channel in there rather than rely on the phantom audio.

[Marcel Birgelen]

Sure, a center channel is far more desirable than working surrounds. The Center channel in Dolby Matrix decoding is essentially just a sum of ~0.7L and ~0.7R. if this sum is higher than L or R (which usually is the case when there is sound coming from the center), the center channel will get some extra attenuation. In practice, this works pretty well for 2.0 sources. There is no phase-shift applied to the center channel, even not on properly encoded soundtracks.

The "Phantom Speaker" effect, where you imagine a source in between two speakers, only works to a certain degree and it seems to differ between people when the concept of "panned sound" starts to fall apart. It usually works less well for the people sitting closest to the speakers.