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tiffmedian - Unix, Linux Command
tiffmedian - apply the median cut algorithm to data in a
tiffmedian applies the median cut algorithm to an
RGB image in
input.tif to generate a palette image that is written to
output.tif. The generated colormap has, by default, 256 entries.
The image data is quantized by mapping each
pixel to the closest color values in the colormap.
Specify the compression to use for data written to the output file:
none for no compression,
packbits for PackBits compression,
lzw for Lempel-Ziv & Welch compression,
zip for Deflate compression.
tiffmedian will compress data according to the value of the
Compression tag found in the source file.
LZW compression can be specified together with a
A predictor value of 2 causes
each scanline of the output image to undergo horizontal
differencing before it is encoded; a value
of 1 forces each scanline to be encoded without differencing.
LZW-specific options are specified by appending a :-separated
list to the lzw option; e.g.
-c lzw:2 for
LZW compression with horizontal differencing.
Specify the number of entries to use in the generated colormap.
By default all 256 entries/colors are used.
Apply Floyd-Steinberg dithering before selecting a colormap entry.
Specify the number of rows (scanlines) in each strip of data
written to the output file.
tiffmedian attempts to set the rows/strip
that no more than 8 kilobytes of data appear in a strip.
This program is derived from Paul Heckberts
Color Image Quantization for Frame Buffer Display, Paul Heckbert, SIGGRAPH proceedings, 1982, pp. 297-307.
Libtiff library home page: