| Linux / Unix Command: ppmtoxpm |
NAME
ppmtoxpm - convert a PPM iamge into an X11 pixmapSYNOPSIS
ppmtoxpm [-name=xpmname] [-rgb=rgb-textfile] [-alphamask=pgmfile] [ppmfile]Minimum unique abbrevations are acceptable.
DESCRIPTION
Reads a portable pixmap as input. Produces X11 pixmap (version 3) as output which can be loaded directly by the XPM library.
For example, to convert the file "dot" (found in /usr/include/X11/bitmaps), from xbm to xpm one could specify
- xbmtopbm dot | ppmtoxpm -name dot
or, with a rgb text file (in the local directory)
-
xbmtopbm dot | ppmtoxpm -name dot -rgb rgb.txt
OPTIONS
- -name=xpmname
- The -name option allows you to specify the prefix string which is printed in the resulting XPM output. If not specified, will default to the filename (without extension) of the <ppmfile> argument. If you do not specify -name or ppmfile, (i.e. your input is from Standad Input), the prefix string defaults to the string noname.
- rgb=rgb-textfile
-
The
-rgb
option allows you to specify an X11 rgb text file for
the lookup of color name mnemonics. This rgb text file is typically
the /usr/lib/X11/rgb.txt of the MIT X11 distribution, but any file
using the same format may be used. When specified and a RGB value
from the ppm input matches a RGB value from the <rgb-textfile>, then
the corresponding color name mnemonic is printed in the XPM's
colormap. If you don't specify
-rgb or if the RGB values don't
match, then
ppmtoxpm produces the color specifications in the #RGB, #RRGGBB,
#RRRGGGBBB, or #RRRRGGGGBBBB hexadecimal format.
- -alphamask=pgmfile
-
This option names a PGM file to use as an alpha (transparency) mask.
The file must contain an image the same dimensions as the input image.
ppmtoxpm
marks as transparent any pixel whose position in the alpha mask image
is at most half white.
If you don't specify -alphamask, ppmtoxpm makes all pixels in the output opaque.
ppmcolormask is one way to generate an alpha mask file. You might also generate it by extracting transparency information from an XPM file with the -alphaout option to xpmtoppm. There are similar options on other Netpbm converters that convert from formats that include transparency information too.
LIMITATIONS
An option to match the closest (rather than exact) color name mnemonic from the rgb text would be a desirable enhancement.Truncation of the least significant bits of a RGB value may result in nonexact matches when performing color name mnemonic lookups.
SEE ALSO
ppmcolormask(1), xpmtoppm(1), ppm(5)XPM Manual by Arnaud Le Hors lehors@mirsa.inria.fr
Important: Use the man command (% man) to see how a command is used on your particular computer.
