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The addtiffo utility is used to add overview pyramids to an existing
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TIFF or GeoTIFF file. Some applications can take advantage of these
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overviews to accelerate overview display performance of large rasters.
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This release of addtiffo is primarily intended for compatibility testing
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with applications, and to see if there is interest in a cleaner release
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of the capability ... perhaps incorporation into the libtiff tools
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Please feel free to contact me with questions, or problems.
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http://home.gdal.org/~warmerda/
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Usage: addtiffo [-r {average/nearest} [-subifd]
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tiff_filename [resolution_reductions]
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% addtiffo abc.tif 2 4 8 16
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The numeric arguments are the list of reduction factors to
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generate. In this example a 1/2, 1/4 1/8 and 1/16
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See tif_overview.cpp for up to date details.
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o Currently only images with bits_per_sample of a multiple of eight
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o The code will attempt to use the same kind of compression,
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photometric interpretation, and organization as the source image, but
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it doesn't copy geotiff tags to the reduced resolution images.
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o Reduced resolution overviews for multi-sample files will currently
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always be generated as PLANARCONFIG_SEPARATE. This could be fixed
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reasonable easily if needed to improve compatibility with other
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packages. Many don't properly support PLANARCONFIG_SEPARATE.
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o Overviews are always written as appended IFDs, rather than using the
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``tree of tree's'' approach using the SUBIFD tag. I wanted to implement
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both, but it isn't currently easy to add a SUBIFD tag to an existing
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main tiff IFD with libtiff. I hope to try this again later.
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The results of running addtiffo on a 1024x1024 tiled greyscale file
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with the arguments ``2 4 8 16'' is to add four additional TIFF directories
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appended on the file with the SUBFILETYPE flag to 0x1 indicating the extra
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items are reduced resolution images.
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The tiffinfo output of such a file might look like this:
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TIFF Directory at offset 0x118008
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Image Width: 1024 Image Length: 1024
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Tile Width: 256 Tile Length: 112
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Compression Scheme: none
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Photometric Interpretation: min-is-black
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Planar Configuration: single image plane
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TIFF Directory at offset 0x15e1d2
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Subfile Type: reduced-resolution image (1 = 0x1)
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Image Width: 512 Image Length: 512
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Tile Width: 256 Tile Length: 112
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Compression Scheme: none
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Photometric Interpretation: min-is-black
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Planar Configuration: separate image planes
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TIFF Directory at offset 0x1732b8
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Subfile Type: reduced-resolution image (1 = 0x1)
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Image Width: 256 Image Length: 256
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Tile Width: 256 Tile Length: 112
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Compression Scheme: none
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Photometric Interpretation: min-is-black
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Planar Configuration: separate image planes
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TIFF Directory at offset 0x17a366
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Subfile Type: reduced-resolution image (1 = 0x1)
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Image Width: 128 Image Length: 128
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Tile Width: 128 Tile Length: 112
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Compression Scheme: none
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Photometric Interpretation: min-is-black
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Planar Configuration: separate image planes
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TIFF Directory at offset 0x17b40c
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Subfile Type: reduced-resolution image (1 = 0x1)
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Image Width: 64 Image Length: 64
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Tile Width: 64 Tile Length: 64
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Compression Scheme: none
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Photometric Interpretation: min-is-black
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Planar Configuration: separate image planes
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You will need a C compiler. You will need to have libtiff already
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built and installed. The provided Makefile should work on most Unix systems.
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A similar file will be needed for Windows, but is not provided.
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The CFLAGS and LIBS macros in the Makefile will have to be updated to
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point to the correct location of the libtiff include files, and library.
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o Intergraph Corporation for partially funding the work.
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o Global Geomatics for partially funding reorganization of the overview
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building ability as a separate utility.
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o Orrin Long, and Ed Grissom of Intergraph for explaining what needed to
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o Max Martinez of Erdas for his discussion of external overviews.
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o Atlantis Scientific who supported adding averaging, and some other
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o Frank Warmerdam for writing the bulk of the code.
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o Sam Leffler since this only exists because of his libtiff.
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contrib/addtiffo/README
