2004.02.09 19:58 "Re: [Tiff] Photoshop 8.0 and libtiff", by Frank Warmerdam

You are going to love this. Currently, I need to be able to handle TIFF images up to 4 GB and in the near future I am sure I will need to work with larger images. My company prints 4 color billboards up to 63 feet by 32 feet, the project I am working is for printing 360 dpi up to that size. I have printed images derived from 2 GB to 4 GB TIFF images before. These images were created in Photoshop 7.0 (with the 2 GB file limit) and then strung together with some propriety software which used one data line per strip. We were hoping that Photoshop 8.0/CS on the G5 would eliminate a step. In the near future I am going to need TIFF files up to 8 GB and maybe larger. So I am going to have to work on a 64 bit version of libtiff.

Don,

The limitation of TIFF to 4GB is implicit in the use of 32bit offsets in the file itself. Changing libtiff won't help you get past 4GB unless you also alter the format - at which point the files won't work with any other application that hasn't been similarly altered. There are other file formats that support larger files. Are you sure you wouldn't be better off looking at them?

That said, I am interested in making some sort of leap to a 64bit TIFF variant at some point with support for it in libtiff. Hopefully in such a way that at least all libtiff based applications would support them. But it is a non-trivial effort, and will be a compatbility nightmare I am sure. For that reason I have put up doing any work on it so far.

Best regards,

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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam@pobox.com
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