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Author Topic: Help playing 4K content. Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 06-02-2015 01:39 AM                     I use opendcp for my 4K content and it's fine, what encoder do they use?  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 06-02-2015 03:14 AM                     Kirk, I tried both DCPs. My Barco is a little shaky at the moment (fan on top) and all I see is a grey screen and I am confident I am not scaling anything here. I suggest you tried a 2pixel pattern.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-02-2015 06:02 AM                     This topic seems very interesting. I'm wondering if there isn't a potential problem of 4K IMB/IMS systems not necessarily processing 4K images properly. I know in the early days of IMBs, there was one prominent IMB that definitely couldn't do it (and never will). Perhaps forum members could run these DCPs on the various IMB/IMS out there and see which ones can actually pass a 4K test pattern unscathed. Please list the make model and software/version numbers used during the test. Include the projector make and ICP version too since that could also affect the end result. Naturally, only 4K systems need apply.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 06-02-2015 08:14 AM                     I don't think, Steve. My 4K chart plays perfectly and scaling can be clearly seen if I scale it. Unless there's an issue with that particular chart, I am pretty much confident that I could not see the lines because my picture was not perfectly steady - an extraction hose will be installed at some point but there's a fan on top of the projector at the time being.  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 06-02-2015 08:49 AM                     Marco - if the IMB does a 2:1 scale to 2k, or simply discards the 4k layer, you won't see it the way normal scaling is visible for your test-chart. Two checkerboard 4k pixels will simply be merged into grey. Even if you suspect your Barco being shaky, you should be able to dissolve 4k Pixels if you simply zoom out with the manual controls on the Barco side panel to magnify the pixel grid as much as the lens allows. Also, if this is really an issue between OpenJPEG and the Doremi IMB, you would need test material from different encoders to compare - like the one I linked to on the last post of the previous page. All general test charts DCPs may have been created using non-OPENJPEG encoders, but I have never seen a chart that can actually be used to depict 4k vs 2k decoding. - Carsten  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 06-02-2015 12:29 PM                     I see your point Carsten but I have small text on my chart with no anti-aliasing. If I show the chart in 2K from the server it looks clearly re-scaled. That is why I am 100% sure that my chart is played back in 4K. I'll try again tomorrow, maybe I'll find a way to move the fan away for a test. Trust me, a Barco with a fan on top will shake to the point you won't be able to see the single lines, I could barely resolve the focus test chart. Kirk, does your Barco have a fan on top - I may have already asked the question, sorry.  |  IP: Logged Kirk Futrell Film Handler Posts: 95 From: Nashville, TN / U.S.A. Registered: Nov 2008 posted 06-02-2015 04:12 PM                        Kevin at the theatre got a chance to try out Carsten's new checkerboard pattern made with the different encoder today. Unfortunately no change. It looks gray too. Doremi is going to remote in to my system tomorrow to see if they can see anything going on. I appreciate how much they have been willing to work with me. Barco has been less supportive, even though our extended warranty is with them. quote: Marco Giustini Trust me, a Barco with a fan on top will shake to the point you won't be able to see the single lines, I could barely resolve the focus test chart. That is not necessarily true. We have a Barco with the heavy invision lens in the hall that we took the original pictures of the problem with. That whole projection booth shakes due to our archaic HVAC equipment being near by. The image shakes visibly on screen even with shock absorption pads, yet You can still easily discern the individual lines when an image from the DCP is used as a test pattern and not played through the Doremi. I'll post the pictures below. The convergence doesn't look spectacular, but it is within spec using the Barco's 4k patterns. This is the 4K test pattern of vertical lines, on a whiteboard 110 ft from the projector using the Flat lens setting. This is the vertical lines DCP made with openDCP from the same location: quote: Steve Guttag Please list the make model and software/version numbers used during the test. Include the projector make and ICP version too since that could also affect the end result. Naturally, only 4K systems need apply. I'll try to provide this information tomorrow. I'm starting to wonder if there is an emperor running around here without any clothes on...  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 06-02-2015 04:38 PM                     I will try again tomorrow if I can - this is getting interesting! I have downloaded the png file and I will test it from the ICP as you did. The Still, I would try with a 2-pixel chart. I feel that we may get some more info on what's happening.  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 06-02-2015 06:09 PM                     Okay, in case FinalDCP still does something strange, here is the line-version of Kirks own test image, corrected by Stéphane, the guy who pointed me to the potential OpenJPEG-Doremi Issue. I don't know exactly what he did - from the CPL I can only assume he uses his own authoring software and worked from Kirks 4k png. https://dl.dropboxusercontent.com/u/5582554/dcp-4K.zip Just to mention this - for all my tests, I also checked the intermediate J2k files directly before they were wrapped into the MXF. I have a few programs that are able to decode and display j2k directly - all my 4k tests still showed the 4k checker pattern in the j2c files - this is a crop from one of these 3996*2160 j2c files: https://dl.dropboxusercontent.com/u/5582554/4kchecker_j2c_crop.jpg So the 4k pixel pattern is definitely contained in those DCPs and it's up to the media block/projector to show it. - Carsten  |  IP: Logged Kirk Futrell Film Handler Posts: 95 From: Nashville, TN / U.S.A. Registered: Nov 2008 posted 06-02-2015 08:52 PM                        Thanks Carsten, I'll check that out tomorrow. In the meantime here is a really great 4K test pattern that Kevin Doyle at the Belcourt just made. It starts of as the left hand 1st quarter of the image from top to bottom is 1 pixel alternating vertical lines to checkerboard to horizontal lines. The next 1/4 is 2 pixel size of the same thing then 4 pixels then 8. If the first 1/4 from left to right is gray then you aren't showing 4K properly. https://drive.google.com/folderview?id=0B5BJx3weEYk8fnRHQ096QW4tTzI5VmhLcmtmbGdab0xHX29pbTR3cGpRN1Zobmh3bHFxOVU&usp=sharing The link should be done uploading in about 10 minutes, but I have to run out so, if it is still processing try again in a bit. I'm not sure uploading an image of it would even work correctly so if you want to see what it looks like click the link. You will have to zoom in on it.  |  IP: Logged Peter Castle Expert Film Handler Posts: 220 From: Wollongong University, NSW ,Australia Registered: Oct 2003 posted 06-02-2015 11:51 PM                     Just tried most of the test clips on our GDC/NEC combination. None of them displayed as anything but a grey image.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-03-2015 12:30 AM                     Which GDC IMB are you using? The older one with the PCIe cable or the current one with the Ethernet cable (or the 3000)? The original can't handle the 4K image. The 2000AR series and the 3000 should be able to handle it.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 06-03-2015 03:21 AM                     I can confirm that the PNG from Kirk works fine and Carten's CPL still displays as a grey pattern. Interesting. I am unable to check the png file at this time, I'll look into that over the weekend.  |  IP: Logged Axel Fransberg Film Handler Posts: 9 From: Helsinki, Finland Registered: Feb 2010 posted 06-03-2015 04:34 AM                     Hi, I made a 4K DCP based on this image http://www.gpsinformation.org/jack/iso-gd-cb-955s.jpg Tested it on both a sony R320 and a NEC+IMB/showvault, both rendered it flawlessly in 4K and if you set the doremi to render it in 2K the image resolution drops noticeably. So it doesn't seem like the doremi is downscaling to 2K and then upscaling back to 4K.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 06-03-2015 05:07 AM                     Again I am 101% sure that the system works in 4K with my framing chart. It must be either a mastering issue or a Doremi issue with that content.  |  IP: Logged

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