TIFFUTIL(1) BSD General Commands Manual TIFFUTIL(1)
NAME
tiffutil - manipulates tiff files
SYNOPSIS
tiffutil <option> [<arguments>] [-out <outfile>]
DESCRIPTION
tiffutil lets you manipulate TIFF files. The list of options (also available by running the program
without any options) follows:
tiffutil -none infile [-out outfile]
-lzw infile [-out outfile]
-packbits infile [-out outfile]
-cat infile1 [infile2 ...] [-out outfile]
-catnosizecheck infile1 [infile2 ...] [-out outfile]
-cathidpicheck infile1 [infile2 ...] [-out outfile]
-extract num infile [-out outfile]
-info infile
-verboseinfo infile
-dump infile
-none, -lzw, and -packbits options specify the compression format to be applied to the images in the
TIFF file. -none specifies no compression; -packbits specifies PackBits compression; -lzw specifies
standard Lempel-Ziv & Welch compression (no prediction scheme).
-cat allows combining multiple TIFF files into one. The images are copied without any change in tag
values. If the real sizes (pixel size divided by dpi) of the images being combined are not the same, a
warning will be generated. This makes sure that NSImage can successfully choose the right size image
out of the generated TIFF file. Use -cathidpicheck to perform a stricter check, conforming to Apple's
guidelines for resolution independent bitmap images. Use -catnosizecheck to bypass the size check.
-extract allows extracting an individual image from a TIFF file; specify num = 0 for the first image in
the file.
-info prints information about TIFF images. -verboseinfo is the same, except most of the tables are
displayed in full. -dump simply lists all of the tags in the file without trying to interpret them; it
is handy when trying to figure out why a TIFF file won't load or display properly.
For options which write images out, the output goes to "out.tiff" unless an output file name is speci-fied specified
fied after a -out keyword. This keyword and the file must be the last items on the command line.
-info, -verboseinfo, and -dump write their output to the standard output.
If there are multiple images in a TIFF file the specified operation will be performed on all of them.
Premultiplying TIFF files with alpha (transparency)
When loading TIFF files into Cocoa apps, you might sometimes see the following warning in the console:
"Warning: TIFF image with unknown extra samples assumed to have unassociated alpha. RGB values have
been premultiplied."
Cocoa and Quartz expect bitmaps with alpha to have the color values premultiplied. Whenever a TIFF file
without premultiplication is loaded using NSImage or NSBitmapImageRep, Cocoa will premultiply the image
for you. There's a slight performance hit to this, so it's best to premultiply the images ahead of
time.
Some paint applications do not do premultiplication, and in addition, they are not quite clear in stat-ing stating
ing what they do with regards to alpha. In those cases you will get the above warning.
tiffutil can be used to fix such files. Simply run the image through with the -cat option:
tiffutil -cat orig.tiff -out new.tiff
This will read orig.tiff and write it out as new.tiff.
CREDITS
Parts of tiffutil were based on the freely distributable "tiffcp" and "tiffinfo" programs written by
Sam Leffler and made available with v3.0 of his excellent TIFF library. The TIFF library and the tiffcp
and tiffinfo programs are:
Copyright (c) 1988, 1989, 1990, 1991, 1992 Sam Leffler
Copyright (c) 1991, 1992 Silicon Graphics, Inc.
Mac OS X August 28, 2002 Mac OS X
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