1994.05.27 23:30 "Re: handling a strip size that's too big", by Dwight Kelly

Is there a way to make the TIFF 3.0 (or TIFF 3.3 beta 002) library read scanline-sized amounts of data instead of strip-size amounts of data?

The reason I ask is that our scanner produces 40MB TIFF files consisting of a single strip. I would like to read the image a scanline (a few KB) at a time. However, since the file consists of just 1 strip, when I call TIFFReadScanline, the TIFF library apparently creates an internal buffer for the entire 40MB strip, which is causing a performance problem.

So to restate my question, is there a way to force TIFF to read one scanline instead of the entire strip? I am under the impression that TIFFReadEncodedStrip and TIFFReadRawStrip are for reading the entire strip. Also, having the scanner write one scanline per strip is not an option.

Version 3.3 has an compile time option that will automatically divide large strips into small chunks. define STRIPCHOP_SUPPORT when you build the library.

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Dwight Kelly
Essential Technical Services, Inc.
3375 Summit Trail Cumming, GA 30131
(404) 889-2848 (404) 889-2624 fax
Internet: dkelly@etsinc.com