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Author Topic: Ingest 5.1 & 7.1 content question ??? Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 03-31-2013 07:45 AM                     Dave, If memory serves, last time I checked - I think it was with 2.2.3 - loading a VF on a Doremi will automatically load the OV. It won't appear on the cinelister but the video track will be loaded as well. That was not the case with earlier versions. Justin, Where do you check the size of the DCP? I believe the server is giving you the size of both Video and Audio even though it's only a VF. It really depends on the distributor but creating an full DCP for all versions is really a waste of time and space. Depending on the server software, you may just see the VF on your server, but the server is smart enough to grab whatever it needs for running that VF, without necessarily listing the OV CPL. Check the actual drive, they are usually organised into folders. Check the size of the 7.1 folder. If it's similar to the 5.1 CPL then you have a full DCP.  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 03-31-2013 08:05 AM                     "But What I care is "Does the 7.1 sound effect lose?" The VF file has 5.1 sound, with 2 stereo surround channels. 7.1 adds a stereo rear surround channel so the surround speakers must be wired in four groups (LS, RS, BSL, BSR) with four amplifier channels. Playing a 7.1 film in a 5.1 auditorium doesn't cause any trouble since the rear tracks just are not there and there's really nothing there anyone will miss unless they've memorized the sound from a 7.1 house. Running 5.1 in a 7.1 house with the system set for 7.1 will have no sound from the rear surround speakers. I doubt if anyone will notice that. If you try to play 7.1 without swapping around the digital audio channels as required, you may hear a "visually impaired" descriptive audio track from a rear channel. That is rather annoying.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 03-31-2013 09:40 AM                     I disagree without disagreeing with you, Dave. Note, you had a typo. the OV file has the 5.1 audio tracks, as required by DCI (5.1 audio being a minimum standard). What I disagree with, while agreeing is the compatibility of a 7.1 version playing well in a 5.1 theatre. One need only play Dolby's Sphere (7.1 version) in 5.1 to hear the problem...that is actual dialog that could be missing (the "All around you" line would be missing parts). Pixar is known for using the separate rear channels with unique audio, including vocal that would vanish if the wrong track was played in the wrong theatre. What I agree with is that one will "get away with it" in many, if not most situations. This does not condone "sound done wrong," however. In the reverse (5.1 played back in a 7.1 theatre in 7.1 mode)...that is less likely to show off the problem though people may think the surround level is low since 1/2 the channels are now off and they were used to "balance" the system. It would be worse than a theatre designed without rear surrounds at all and balanced that way. But again, it is unlikely that the typical movie goer would know what was wrong (aside, maybe, that the surround were not loud enough...since they always think surround should be omnipresent anyway). I fault the industry for not handling this issue entirely. That is, there should be metadata on each movie that allows the theatre to "configure itself" based on capability. That if a theatre doesn't have the newer, higher features, it should automatically play the "standard" version. Only if the theatre is configured for the new feature should it use the better version. When the tech sets up the server/projector, those features are checked off and the appropriate version is used. As each new feature comes out (doesn't just have to be sound), server software can be patched to allow for the new format. Alas, we do not live in that world...people must still know what they have and figure out what is proper to use on a case-by-case.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 03-31-2013 12:45 PM                     I disagree without disagreeing with you, Steve. The simple solution is to simply duplicate the LS and RS channels on the two rear wall channels on 5.1 mixes so there isn't anything to change. Putting the descriptive audio channels there on 5.1 mixes is just foolish. This is similar logic to a 1.85 matte 35mm print. That prevents the lesser professionals from showing boom mics and such. Of course the industry is retarded when it comes to good, simple ideas.  |  IP: Logged Justin Hamaker Film God Posts: 2253 From: Lakeport, CA USA Registered: Jan 2004 posted 03-31-2013 12:50 PM                        @Marco: I am viewing the size of the file in the content list on my library server. I am not able to view what's on the actual hard drive because most my content is delivered via satellite and I rarely receive hard drives - especially not for major studio releases. Looking back through my projectionist letters, I can see instances where it specifically states the 7.1 is a partial package. In these cases, the CPL has both OV and VF in the file name. However, in the case of the Croods,the CPL name has OV two times.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 03-31-2013 01:59 PM                     Duplicating the Rs and Ls on ch 11 and 12 for 5.1 mixes is simply a great idea in my opinion. Not only would it prevent the wrong format to be used - as pointed out by Steve - but also it would allow the cinema to leave the sound processor in 7.1 all the time and the surround levels could be set more accurately - the reason is that when I set surround levels to standard, 82dBC, I usually find that when an entire side is used (i.e. Ls+LBs) the result is not necessarily 85dB for, I guess, acoustic reasons. Brad's simple idea would just avoid a number or issues. And I don't really think that an extra Gigabyte of data would be a problem. The difference in level when you run a 5.1 soundtrack in 7.1 is around 3dB so yes, it does matter!  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 03-31-2013 05:31 PM                     See, I would put that burden on the server, not the content creator. GDC can actually sort of can do this with their channel mapping feature. While there is a 5.1 channel definition in DCI and where those channels go...that is not the case for 7.1. It is the wild-west for greater than 5.1 mixes. Thus, it would be a simple matter for a server to see it is a 5.1 mix (via title naming, or looking at the audio files supplied or metadata) to see that it is a 5.1 mix and merely put the Ls and Rs on the back channels too. This also would allow for mixes that pre-exist BEFORE the new format is created to play back properly. What is really stupid is the HI/VI-N. First and foremost...what is the point of the HI track? Anyone that does not use the processor's LCR mix (with center emphasis) is stupid. Why? If the movie doesn't have an HI track, then you get NOTHING for the impaired...so you would have to keep track of what movie is playing to ensure the HI system is always getting something. Then there are the trailers, which don't have HI tracks, from what I can tell. At the moment, most HI/VI-N tracks are residing on channels 7/8...the "Interrop" format. Why on Earth are we also looking to move them on 15/16? The train has left the station on that one. Yes, 7/8 were supposed to be the LC/RC tracks but let LC/RC move...how many movies have been mixed with them on DCP? How many are using 7/8 for HI/VI-N? Free up 15/16 for something else, let LC/RC move to 9/10 or 15/16...pick one and let it stick. Channels 1-8 should be engraved in stone by now and dependable as to what is on them for all movies, regardless of origin. Server companies should be compelled to handle channel mapping, as needed to be DCI compliant, if they are to handle newer formats.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 03-31-2013 06:13 PM                     I couldn't agree more. As EX days, where most of the cinemas were either running everything in EX or everything in 5.1 - trusting the 'Auto EX' which too many times was wrong set - the bottom line is: do it automatic. In these Digital days there is really NO reason for that not to happen, in a way or another.  |  IP: Logged Harold Hallikainen Jedi Master Film Handler Posts: 906 From: Denver, CO, USA Registered: Aug 2009 posted 03-31-2013 09:09 PM                        A few comments on audio routing: 1. SMPTE packages support audio routing. Interop does a 1:1 mapping. The assumed Interop mapping at this point is described here. The end result is auditorium wiring of AES/EBU channels according to this layout (ie, Lrs/Rrs on 11/12). Content is still shipping in Interop (not SMPTE) format. 2. Because of the lack of routing in Interop, auditoriums are wired according to the Interop channel layout. Discussions at ISDCF have suggested that the server should assume as a default that the auditorium is wired in this manner and that SMPTE routing should follow this assumption. This comes down putting default values in the SMPTE audio routing table based on wiring due to Interop. 3. Of course, cinema processors have been generating an HI signal for many years. This is generally an LCR mix with dynamic range compression (though the compression is typically done in the HI transmitter instead of the cinema sound processor). It is possible, however, for the content provider to make an even better HI track (with dialog more clear than an LCR mix). I think, however, that the HI tracks currently being delivered are compressed LCR mixes with a fixed mix and compression ration (pretty much what a cinema processor would provide). The HI track seems to be the last thing created and generally does not get created for trailers due to the extremely tight deadlines. Some HI equipment uses AES 7 for its one and only audio input. The result is no HI during trailers. ISDCF has been pushing for an HI track on all content. Harold  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 04-03-2013 06:31 PM                     We use a datasat AP20 with two DCI format presets, one for 5.1, one for 7.1. There is no automatic switching yet, due to the lack of metadata or other intelligence in detecting the audio format (which could e.g. be using an SDDS layout as well). Will come with full SMPTE DCPs some day. We use format cues in the SPL to switch the AP20 from 5.1 during trailers to 7.1 for the main feature. In 5.1 mode, the datasat uses an internal routing to copy surround channels to rear surrounds and compensate levels. In addition, the Sony SRX-R515 IMB has a simple audio switching matrix to mask out HI/VI and copy 11/12 to 7/8. Could be done on the AP20 (16ch) as well, but for 8ch processors, doing it on the IMB or with a breakout board switching over 7/8 vs. 11/12 AES channels are the only options. Doremi has the same audio matrix feature. - Carsten  |  IP: Logged Ian Freer Expert Film Handler Posts: 135 From: Wellington, New Zealand Registered: Oct 2003 posted 04-06-2013 11:44 PM                     GDC Servers also have audio routing options built in. You can specify individual routing options based on how many channels of audio are actually presented in the DCP. Datasat has the H506 adaptor board that has a couple of jumpers to choose how 7/8 & 11/12 are routed that can be used with all 3 versions of the AP20 if software routing is not available from your server.  |  IP: Logged

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