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ppmtosixel(1) [opensolaris man page]

ppmtosixel(1)                                                 General Commands Manual                                                ppmtosixel(1)

NAME
ppmtosixel - convert a portable pixmap into DEC sixel format SYNOPSIS
ppmtosixel [-raw] [-margin] [ppmfile] DESCRIPTION
Reads a portable pixmap as input. Produces sixel commands (SIX) as output. The output is formatted for color printing, e.g. for a DEC LJ250 color inkjet printer. If RGB values from the PPM file do not have maxval=100, the RGB values are rescaled. A printer control header and a color assignment table begin the SIX file. Image data is written in a compressed format by default. A printer control footer ends the image file. OPTIONS
-raw If specified, each pixel will be explicitly described in the image file. If -raw is not specified, output will default to com- pressed format in which identical adjacent pixels are replaced by "repeat pixel" commands. A raw file is often an order of magni- tude larger than a compressed file and prints much slower. -margin If -margin is not specified, the image will be start at the left margin (of the window, paper, or whatever). If -margin is speci- fied, a 1.5 inch left margin will offset the image. PRINTING
Generally, sixel files must reach the printer unfiltered. Use the lpr -x option or cat filename > /dev/tty0?. BUGS
Upon rescaling, truncation of the least significant bits of RGB values may result in poor color conversion. If the original PPM maxval was greater than 100, rescaling also reduces the image depth. While the actual RGB values from the ppm file are more or less retained, the color palette of the LJ250 may not match the colors on your screen. This seems to be a printer limitation. SEE ALSO
ppm(5) AUTHOR
Copyright (C) 1991 by Rick Vinci. 26 April 1991 ppmtosixel(1)

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pnmremap(1)						      General Commands Manual						       pnmremap(1)

NAME
pnmremap - replace colors in a PPM image with colors from another set SYNOPSIS
pnmremap [-floyd|-fs|-nfloyd|-nofs] [-firstisdefault] [-verbose] [-mapfile=mapfile] [-missingcolor=color] [pnmfile] All options can be abbreviated to their shortest unique prefix. You may use two hyphens instead of one to designate an option. You may use either white space or an equals sign between an option name and its value. DESCRIPTION
pnmremap replaces the colors in an input image with those from a colormap you specify. Where a color in the input is not in the colormap, you have three choices: 1) choose the closest color from the colormap; 2) choose the first color from the colormap; 3) use a color speci- fied by a command option. (In this latter case, if the color you specify is not in your color map, the output will not necessarily contain only colors from the colormap). Two reasons to do this are: 1) you want to reduce the number of colors in the input image; and 2) you need to feed the image to something that can handle only certain colors. To reduce colors, you can generate the colormap with ppmcolormap. Example: ppmcolormap testimg.ppm 256 >colormap.ppm ppmremap -map=colormap.ppm testimg.ppm >reduced_testimg.ppm To limit colors to a certain set, a typical example is to create an image for posting on the World Wide Web, where different browsers know different colors. But all browsers are supposed to know the 216 "web safe" colors which are essentially all the colors you can represent in a PPM image with a maxval of 5. So you can do this: ppmcolors 5 >websafe.ppm ppmremap -map=webafe.ppm testimg.ppm >websafe_testimg.ppm The output image has the same type and maxval as the map file. PARAMETERS
There is one parameter, which is required: The file specifcation of the input PNM file. OPTIONS -floyd -fs -nofloyd -nofs These options determine whether Floyd-Steinberg dithering is done. Without Floyd-Steinberg, the selection of output color of a pixel is based on the color of only the corresponding input pixel. With Floyd-Steinberg, multiple input pixels are considered so that the average color of an area tends to stay more the same than without Floyd-Steinberg. For example, if you map an image with a black, gray, gray, and white pixel adjacent, through a map that contains only black and white, it might result in an output of black, black, white, white. Pixel-by-pixel mapping would instead map both the gray pixels to the same color. -fs is a synomym for -floyd. -nofs is a synonym for -nofloyd. The default is -nofloyd. -firstisdefault This affects what happens with a pixel in the input image whose color is not in the map file. If you specify neither -firstisde- fault nor -missingcolor, pnmremap chooses for the output the color in the map which is closest to the color in the input. With -firstisdefault, pnmremap instead uses the first color in the colormap. If you specify -firstisdefault, the maxval of your input must match the maxval of your colormap. -missingcolor=color This affects what happens with a pixel in the input image whose color is not in the map file. If you specify neither -firstisde- fault nor -missingcolor, pnmremap chooses for the output the color in the map which is closest to the color in the input. With -missingcolor, pnmremap uses color. color need not be in the colormap. If you specify -missingcolor, the maxval of your input must match the maxval of your colormap. -verbose Display helpful messages about the mapping process. SEE ALSO
pnmcolormap(1), ppmcolors(1), pnmquant(1), ppmquantall(1), pnmdepth(1), ppmdither(1), ppmquant(1), ppm(5) AUTHOR
Copyright (C) 1989, 1991 by Jef Poskanzer. Copyright (C) 2001 by Bryan Henderson. 01 January 2002 pnmremap(1)
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