2007.07.12 15:21 "[Tiff] how to rotate an image", by Oliver Geisen

2007.07.14 12:45 "Re: [Tiff] how to rotate an image", by Oliver Geisen


How large are the images you're rotating? Our pre-press product FirstPROOF has the ability to rotate 1-bit images, by 90, 180 or 270 degrees, very fast, however big they

The images are 16300x27501 pixels, bilevel, which makes them abount 48MB of size (unpacked).

I can force images to be stripped or tiled. For now i use striped.

are, whether they are striped or tiled. I can tell you that writing such code to be efficient for any sized images (and leaving a resulting image that is sequentially accessed on disk for subsequent maximum i/o performance) is not a trivial task. If you're not an experienced s/w engineer, I would suggest you hire one.

I think you are right, but i want to know how to do that :-) I would not title myself as an experienced s/w engineer, but i would be very pleased to learn from one...

So could you give me some tips how to do rotation/bit shifting very fast?

Oliver Geisen
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