2006.01.03 16:37 "Re: [Tiff] Strip Vs Tile", by Joris Van Damme

Pallek, Bernie: #CIPO - OPIC wrote:

My Query is regarding the layout of Tiff Images.

When to save a Tiff image as Tiled and when to save a Tiff image as Strip?? While saving, should we consider the layout of the original Tiff image which we opened??

The TIFF spec 6.0 recommends a strip size of 8K (before compression).

That is mainly because the TIFF 6.0 spec was written when - most of us were playing in a 64 kilobyte yard - tiling was relatively new those days

IMO, what Bob said makes a lot more sense. If you don't need tiles, use strips. Saving large images (say over 4 kilopixels wide and high), you need tiles. I should add that for certain color spaces and compression modes, like black and white G3 or G4 compressed, it is customary to save a single strip even if the image is somewhat bigger then 4 kilopixels.

As to the strip/tile size, these days, I would almost recommend 8 megabyte rather then 8 kilobyte. We've recently learned on the list that Photoshop's new strategy is to use as large a buffer as is affordable on the machine in the run-time circumstances (though I'm not sure how exactly 'affordable' is defined), because it helps getting the best possible compression ratio and saves IO calls and fragmentation.

When saving data in general, IMO, you should try to preserve as much of the original "framing" as possible. In other words, preserve byte-ordering, stripping, compression format, IFD layout, whatever offsets you can, and even any custom tags that your software may not understand or care about.

That is bad advice. Don't ever blindly preserve. You may be preserving data that is no longer valid after your operations.

Joris Van Damme
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