2007.08.22 06:13 "[Tiff] How to handle big single-strip images?", by Oliver Geisen

2007.08.22 12:19 "Re: [Tiff] How to handle big single-strip images?", by Toby Thain

On 22-Aug-07, at 6:36 AM, jcupitt@gmail.com wrote:

On 8/22/07, Oliver Geisen <oliver.geisen@kreisbote.de> wrote:

i wonder what will happen if one opens an tiff image where all the data is in a SINGLE strip (some writers offer this option) and also compressed (G4) and someone tries to use TIFFReadScanline with it? I would expect that libtiff needs to read the whole strip, because it's compressed, into memory. Or is it possible to read compressed data by chunks?

This is what the tiled mode is for. Strip TIFFs (as you say) are not very suitable for random access.

Wouldn't that only depend on the strip size?


Tiled TIFFs work well with random access, even with compression.

We use JPEG-compressed tiled TIFF pyramids in our web image viewer and performance is good. There's a demo with a 80,000 by 40,000 pixel image here:


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