2005.09.12 21:22 "[Tiff] read-by-scan-line buffers full strip, part 2", by
Mark Pilon
Thread
2005.09.13 16:17 "[Tiff] read-by-scan-line buffers full strip, part 3", by Mark Pilon
the details:
I need to access a particular tiff image, some small (and arbitrary) # of lines at a time. 1 if necessary;
when I try to read this image w/ TIFFReadScanline(), a 60+ Mb buffer is allocated for the entire strip/image -- the image is large, color and one strip.
I need to process the image sequentially w/o any random access.
the tiffinfo for this image:
[mpilon@mars mpilon]$ tiffinfo /rd/tests/gld/tiff/QL/TQ1RCLCE.tif
TIFF Directory at offset 0x8
Subfile Type: multi-page document (2 = 0x2)
Image Width: 4048 Image Length: 4420
Resolution: 1200, 1200 pixels/inch
Bits/Sample: 8
Compression Scheme: LZW
Photometric Interpretation: RGB color
Orientation: row 0 top, col 0 lhs
Samples/Pixel: 3
Rows/Strip: 4420
Planar Configuration: single image plane
Page Number: 0-0
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unfortunately, it seems that libtiff won't be easily modified to uncompress only part of a strip at a time... and before beginning such a significant modification, I thought I'd ask if there was any other way to get to the data...
using libtiff part-way to get access to the compressed data, but the decompression in smaller increments than the whole strip. perform
thanks for the replies -- please send more!
Mark