Rasttopnm User Manual(0) Rasttopnm User Manual(0)NAMErasttopnm - convert a Sun rasterfile to a PNM image
SYNOPSISrasttopnm
[-index]
[rastfile]
DESCRIPTION
This program is part of Netpbm(1).
rasttopnm reads a Sun rasterfile as input and produces a PNM image as
output. The type of the output file depends on the input file - if
it's black and white, rasttopnm writes a PBM image. If it's grayscale,
rasttopnm writes a PGM. If it's color, rasttopnm writes a PPM. The
program tells you which type it is generating.
OPTIONS-index This odd option tells rasttopnm to use the color map indices in
the raster as if they are the color values.
In a colormapped Sun rasterfile, the header of the file contains
a color map, associating each unique color that occurs in the
file with an index number. The raster portion of the file then
represents the color of a pixel with one of those colormap
indices.
This option has found use as follows: take a regular grayscale
Sun rasterfile in which all the grayscale value are represented,
so the colormap indices are identical to the color values. Mod‐
ify its color map so as to alter the colors in the image, in
particular to equalize the colors. With that modified raster‐
file as input, rasttopnm without -index produces the modified
image. But with -index, it produces the original unmodified
image.
This option was new in Netpbm 10.56 (September 2011).
SEE ALSOpnmtorast(1), pnm(1)AUTHOR
Copyright (C) 1989, 1991 by Jef Poskanzer.
netpbm documentation 16 August 2011 Rasttopnm User Manual(0)