4
The addtiffo utility is used to add overview pyramids to an existing
5
TIFF or GeoTIFF file. Some applications can take advantage of these
6
overviews to accelerate overview display performance of large rasters.
8
This release of addtiffo is primarily intended for compatibility testing
9
with applications, and to see if there is interest in a cleaner release
10
of the capability ... perhaps incorporation into the libtiff tools
13
Please feel free to contact me with questions, or problems.
16
http://members.home.com/warmerda
22
Usage: addtiffo [-r {average/nearest} [-subifd]
23
tiff_filename [resolution_reductions]
26
% addtiffo abc.tif 2 4 8 16
28
The numeric arguments are the list of reduction factors to
29
generate. In this example a 1/2, 1/4 1/8 and 1/16
36
See tif_overview.cpp for up to date details.
38
o Currently only images with bits_per_sample of a multiple of eight
41
o The code will attempt to use the same kind of compression,
42
photometric interpretation, and organization as the source image, but
43
it doesn't copy geotiff tags to the reduced resolution images.
45
o Reduced resolution overviews for multi-sample files will currently
46
always be generated as PLANARCONFIG_SEPARATE. This could be fixed
47
reasonable easily if needed to improve compatibility with other
48
packages. Many don't properly support PLANARCONFIG_SEPARATE.
50
o Overviews are always written as appended IFDs, rather than using the
51
``tree of tree's'' approach using the SUBIFD tag. I wanted to implement
52
both, but it isn't currently easy to add a SUBIFD tag to an existing
53
main tiff IFD with libtiff. I hope to try this again later.
59
The results of running addtiffo on a 1024x1024 tiled greyscale file
60
with the arguments ``2 4 8 16'' is to add four additional TIFF directories
61
appended on the file with the SUBFILETYPE flag to 0x1 indicating the extra
62
items are reduced resolution images.
64
The tiffinfo output of such a file might look like this:
66
TIFF Directory at offset 0x118008
67
Image Width: 1024 Image Length: 1024
68
Tile Width: 256 Tile Length: 112
70
Compression Scheme: none
71
Photometric Interpretation: min-is-black
73
Planar Configuration: single image plane
74
TIFF Directory at offset 0x15e1d2
75
Subfile Type: reduced-resolution image (1 = 0x1)
76
Image Width: 512 Image Length: 512
77
Tile Width: 256 Tile Length: 112
79
Compression Scheme: none
80
Photometric Interpretation: min-is-black
82
Planar Configuration: separate image planes
83
TIFF Directory at offset 0x1732b8
84
Subfile Type: reduced-resolution image (1 = 0x1)
85
Image Width: 256 Image Length: 256
86
Tile Width: 256 Tile Length: 112
88
Compression Scheme: none
89
Photometric Interpretation: min-is-black
91
Planar Configuration: separate image planes
92
TIFF Directory at offset 0x17a366
93
Subfile Type: reduced-resolution image (1 = 0x1)
94
Image Width: 128 Image Length: 128
95
Tile Width: 128 Tile Length: 112
97
Compression Scheme: none
98
Photometric Interpretation: min-is-black
100
Planar Configuration: separate image planes
101
TIFF Directory at offset 0x17b40c
102
Subfile Type: reduced-resolution image (1 = 0x1)
103
Image Width: 64 Image Length: 64
104
Tile Width: 64 Tile Length: 64
106
Compression Scheme: none
107
Photometric Interpretation: min-is-black
109
Planar Configuration: separate image planes
115
You will need a C compiler. You will need to have libtiff already
116
built and installed. The provided Makefile should work on most Unix systems.
117
A similar file will be needed for Windows, but is not provided.
119
The CFLAGS and LIBS macros in the Makefile will have to be updated to
120
point to the correct location of the libtiff include files, and library.
126
o Intergraph Corporation for partially funding the work.
128
o Global Geomatics for partially funding reorganization of the overview
129
building ability as a separate utility.
131
o Orrin Long, and Ed Grissom of Intergraph for explaining what needed to
134
o Max Martinez of Erdas for his discussion of external overviews.
136
o Atlantis Scientific who supported adding averaging, and some other
139
o Frank Warmerdam for writing the bulk of the code.
141
o Sam Leffler since this only exists because of his libtiff.