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TIFF and LibTiff Mail List Archive

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2008.01.10 19:03 "[Tiff] LibTiff..Reading partial strips", by Nikhil Shirahatti
2008.01.10 21:33 "Re: [Tiff] LibTiff..Reading partial strips", by Bob Friesenhahn
2008.01.10 21:40 "Re: [Tiff] LibTiff..Reading partial strips", by Nikhil Shirahatti
2008.01.10 22:01 "Re: [Tiff] LibTiff..Reading partial strips", by Bob Friesenhahn
2008.01.11 07:35 "Re: [Tiff] LibTiff..Reading partial strips", by
2008.01.10 22:08 "Re: [Tiff] LibTiff..Reading partial strips", by Frank Warmerdam
2008.01.10 22:48 "Re: [Tiff] LibTiff..Reading partial strips", by Nikhil Shirahatti
2008.01.10 23:04 "Re: [Tiff] LibTiff..Reading partial strips", by Nikhil Shirahatti
2008.01.11 00:59 "Re: [Tiff] LibTiff..Reading partial strips", by Bob Friesenhahn
2008.01.11 07:40 "Re: [Tiff] LibTiff..Reading partial strips", by
2008.01.11 18:01 "[Tiff] Scanline access in libtiff", by Richard Nolde
2008.01.12 09:32 "Re: [Tiff] Scanline access in libtiff", by

2008.01.11 07:40 "Re: [Tiff] LibTiff..Reading partial strips", by

Frank,

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.

TIFFReadScanline and that sort of access might be more optimally streaming. But support for it depends on the particular subcodec, and I seem to remember not all subcodecs support it. It does not work on tiled images, either, and since there's no actual definition in the man pages of what should be returned on subsampled images, there's a bit of a mess in that case. So I essentially regard this scanline based access a broken concept in LibTiff.

Best regards,

Joris Van Damme
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