I have a finished, tested and working, 4K DCP of my feature film. I need a 2K one as well.
Is it a viable route to simply import the DCP i DCP-o-matic and ask it to export a new one in 2K? I am not sure if the J2C compression would suffer.
And how good is DCP-o-matic at scaling stuff?
Downscaling a 4k DCP - is it a good idea
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Kewl
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Re: Downscaling a 4k DCP - is it a good idea
You could also consider making the 2K DCP from the original source file.
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gi-jones
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Re: Downscaling a 4k DCP - is it a good idea
I exported the J2C sequence directly from Resolve. I could obviously do that again in 2K, but it would take quite a while.
Hence my question
Hence my question
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Carsten
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Re: Downscaling a 4k DCP - is it a good idea
Why do you need a separate 2k DCP?
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gi-jones
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Re: Downscaling a 4k DCP - is it a good idea
If it needs to be displayed in a 2K theater
I did some tests, and besides obvious drawback of delivering a full 4K dcp (which is 160GB in this case) there is also notable scaling issues with playing back a 4K on a 2K projector.
But all that aside, I'd still really like to know if anyone sees a problem scaling down from the 4k J2C files.
I did some tests, and besides obvious drawback of delivering a full 4K dcp (which is 160GB in this case) there is also notable scaling issues with playing back a 4K on a 2K projector.
But all that aside, I'd still really like to know if anyone sees a problem scaling down from the 4k J2C files.
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Carsten
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Re: Downscaling a 4k DCP - is it a good idea
4k DCPs are played in 2k theatres all the time. Even top selling blockbusters don't get dual 4k and 2k DCPs. DCI/DCP has been designed that way. In 2k theatres, only the 2k resolution layer is played, and the 4k layer is ignored.
Also, the data rate for 2k and 4k is essentially the same. I see no difference between DCP sizes of 2k vs. 4k when I look at the commercially created DCPs we play.
If you still insist, just create a 2K DCP from the original master file, by just flipping the resolution from 4k to 2k under the DCP tab. Creating 2k from 4k just creates a new compression generation.
Also, the data rate for 2k and 4k is essentially the same. I see no difference between DCP sizes of 2k vs. 4k when I look at the commercially created DCPs we play.
If you still insist, just create a 2K DCP from the original master file, by just flipping the resolution from 4k to 2k under the DCP tab. Creating 2k from 4k just creates a new compression generation.
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IoannisSyrogiannis
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Re: Downscaling a 4k DCP - is it a good idea
Indeed!
How I wish one could just strip off the extra data of a 4K to end up with 2K!
(I am not talking about DCP-o-matic necessarily. If anyone has an ffmpeg line to share for re-muxing/stripping, I would be more than happy to read.)
That would solve some storage issues on old, 1,8 TBs servers.
Also, it could help with the scenario of taking advantage of a server capable to safely go beyond 250Mbps (like ICMP/-X) and make another version for any other server. All that, while loosing no significant time to re-encode and keeping the exact same quality that would screen on a 2K projector with a 4K DCP.
A personal point of view: When a 2K and a 4K DCP version have the same bitrate, it's a waste of money.
How I wish one could just strip off the extra data of a 4K to end up with 2K!
(I am not talking about DCP-o-matic necessarily. If anyone has an ffmpeg line to share for re-muxing/stripping, I would be more than happy to read.)
That would solve some storage issues on old, 1,8 TBs servers.
Also, it could help with the scenario of taking advantage of a server capable to safely go beyond 250Mbps (like ICMP/-X) and make another version for any other server. All that, while loosing no significant time to re-encode and keeping the exact same quality that would screen on a 2K projector with a 4K DCP.
A personal point of view: When a 2K and a 4K DCP version have the same bitrate, it's a waste of money.