Creating a 4K DCP from a Blu-ray...
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hal9000
- Posts: 4
- Joined: Sat Nov 16, 2013 5:51 am
Creating a 4K DCP from a Blu-ray...
If you were to convert a Blu-ray movie like "2001: A Space Odyssey," which is just an ordinary 2K release, would it be beneficial AT ALL to create the DCP file in 4K? I know it wouldn't magically improve anything. The DCP can only be as good as the source. But since you're blowing up the picture to a fairly large theatre screen size, would 4K help in taking away any degradation in the image? Sorry if this is a dumb question, but I've always wondered that.
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stereo3d
- Posts: 6
- Joined: Sat Aug 30, 2014 5:57 am
Re: Creating a 4K DCP from a Blu-ray...
the problem with blowing up the BR on a large screen like this, is that you will probably be lacking bit depth.
this might be acceptable on a small television. But if you have only 8bit color depth, especially with space movies,
you might end up with very large color banding artifacts. This is why the DCI specs define 12bit color depth for a
professional image quality. You might need to apply some color dithering.
As you might know the server capacity is also limited by the bandwidth in most cases. So you will have to choose
if you like to have a 2k image with the highest compression quality or a 4k image with more compression, since you will have the
same bandwidth in the end.
I believe there will be no gain in quality, by going to 4k, the 8bit image might not look as good as you expect when you go to the large screen.
this might be acceptable on a small television. But if you have only 8bit color depth, especially with space movies,
you might end up with very large color banding artifacts. This is why the DCI specs define 12bit color depth for a
professional image quality. You might need to apply some color dithering.
As you might know the server capacity is also limited by the bandwidth in most cases. So you will have to choose
if you like to have a 2k image with the highest compression quality or a 4k image with more compression, since you will have the
same bandwidth in the end.
I believe there will be no gain in quality, by going to 4k, the 8bit image might not look as good as you expect when you go to the large screen.
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Carsten
- Posts: 2804
- Joined: Tue Apr 15, 2014 9:11 pm
- Location: Germany
Re: Creating a 4K DCP from a Blu-ray...
Well first of all, an upscaled version can never be any better than the native version. Scaling always introduces artifacts. They may not be visible, but they are there. Then, it could only make sense to create a 4k DCP if you also use a 4k projector for playback. But if you play back a 2k DCP on that 4k projector, it will automatically scale the image to 4k. Now wether that projector-side scaling looks any better than your offline scaling, I won't pick up that discussion.
Whenever possible, use the native source resolution. If the BluRay has 1920*1080 - don't scale it to 1998 or 2048 just to fill the screen. Most people will never see the difference, but it is just not the proper workflow to minimize conversion artifacts.
- Carsten
Whenever possible, use the native source resolution. If the BluRay has 1920*1080 - don't scale it to 1998 or 2048 just to fill the screen. Most people will never see the difference, but it is just not the proper workflow to minimize conversion artifacts.
- Carsten