Dan Hudgins
Well-known member
- Joined
- Feb 16, 2007
- Messages
- 1,369
- Reaction score
- 0
- Points
- 0
- Location
- San Francisco, CA USA
- Website
- www.dancad3d.com
so you are saying that Prores 4444 is not the same thing as 10-bit uncompressed? How would one output a 10-bit uncompressed file from our FCP/DNxHD file?
A DPX sequence for the whole movie would end up being about 2TB to 4TB depending on the film length and OS used. So you will need one or two 2TB disks to store the frame image files on as a set with numbered filenames. If you need to break the film to fit on two disks, you need to be able to have the numbers continue on the second disk I would think where you left off on the first disk.
For filmout I would do it by the reel since you can only max. 22 minutes of film in the film recorder.
Is Prores4444 just a single file? If so it would be a very large file for the whole film, so if your disk is not big enough you need to span disks as well, but since its a data stream you cannot just break it. One safe way to break large files might be to use a zip program to cut it into parts small enough to put on a set of disks, the later the user can put the parts back together on their RAID array using un-zip. I have been dealing with some huge uncompressed files that way, by ftp you can waste quite a bit of time if the xfer will not restart on big files, but if you break them into say 10MB numbered parts, the Xfer can restart and just need to re-transmit the 10MB that got messed up. I've been using 7-zip as its free and breaks up large files, but I have not tried it yet on anything as large as 2TB so far...
In making the DPX frames you need to know the pixel format and if you need the sound track area, that is 2048 wide 1556 high but with the image width 1828. 709 64 to 940 or Cineon (tm) 95-685 limits. If you go from 709 to Cineon (tm) you should not need softclip since the highlights should be under 685 level.
It sounds like you need to talk to the people more and find out exactly how they want things.
Also is the issue of the sound, if they want 24.000fps for DCP/filmout or is the sound at 23.976fps, since you sound may be two hours long you need the frame rate right for it to play the right length.
It can take days to convert all the files depending on your system since its 24*60*88=126720 DPX frames or more, each one 2048x1556x4=12.8MB each, so
12.8*126720=1.63TB for the data, but files take more disk space than their data so I'm not sure that would fit on a 2TB drive or not.
You can open each DPX frame and look at it, and its data should be stable since Cineon (tm) DPX are a well supported "standard" format for images,
http://www.celco.com/FormatResolutionTableKodakCineon.asp
I'm finishing up 10bpc and 16bpc DPX support for my DI system since it will interface to just about any workflow in a more or less predictable way.