2008.01.10 22:08 "Re: [Tiff] LibTiff..Reading partial strips", by Frank Warmerdam

I havent tried it..but the cautionary note that " It is not always possible to do so due to decompression constraints" scares me. I also read on the archive that "that *strip* only works for * chopping* uncompressed IFDs.". How common(or uncommon) is this? When would one use compressed IFD's?

 The tiff's we get can be compressed or uncompressed formats and we have to
support them all. :)

Nikhil,

I think Bob means compressed images. There is no such thing as compressed IFDs. Compressed TIFF images are quite a common case, and fax compressed images are often one strip.

In addition to "strip chopping", libtiff also has the TIFFReadScanline() function for reading strips one scanline at a time. This operates without needing to read and decompress the whole strip at once.

Best regards,
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