Man Pages

ppmtobmp(1) - phpMan ppmtobmp(1) - phpMan

Command: man perldoc info search(apropos)  


Ppmtobmp User Manual(0)                                Ppmtobmp User Manual(0)



NAME
       ppmtobmp - convert a PPM image into a BMP file


SYNOPSIS
       ppmtobmp

       [-windows]

       [-os2]

       [-bpp=bits_per_pixel]

       [-mapfile=filename]

       [ppmfile]

       Minimum  unique  abbreviation  of option is acceptable.  You may use double hyphens instead of single hyphen to
       denote options.  You may use white space in place of the equals sign to separate an option name from its value.



DESCRIPTION
       This program is part of Netpbm(1).

       ppmtobmp reads a PPM image as input and produces a Microsoft Windows or OS/2 BMP file as output.


OPTIONS
       -windows
              Tells the program to produce a Microsoft Windows BMP file.  (This is the default.)


       -os2   Tells the program to produce an OS/2 BMP file.  (Before August 2000, this was the default).


       -bpp   This tells how many bits per pixel you want the BMP file to contain.  Only 1, 4, 8, and 24 are possible.
              By default, ppmtobmp chooses the smallest number with which it can represent all the colors in the input
              image.  If you specify a number too small to represent all the colors in the input image, ppmtobmp tells
              you and terminates.  You can use pnmquant or ppmdither to reduce the number of colors in the image.


       -mapfile=filename
              This identifies a file to use as the BMP palette (aka 'colormap').  In one BMP subformat, the BMP stream
              contains  a  palette  of up to 256 colors, and represents the image raster as indices into that palette.
              Normally, ppmtobmp takes care of computing a suitable palette, but if you are going to dissect  the  BMP
              output  in some way, you may want certain values for the palette indices.  E.g. you might want red to be
              13, where ppmtobmp would (arbitrarily) choose 39.  In that case, you can construct the palette  yourself
              and use this option to tell ppmtobmp to use your palette.

              This  option does not control what colors are in the output.  The colors in the output are exactly those
              in the input, and the palette you supply must contain at least all the colors that  are  in  the  input.
              You can use pnmremap to adjust your input image so that it contains only colors from your palette.

              The  palette file is a Netpbm format file with one pixel per palette entry.  Each pixel must have a dis-
              tinct color (no repeats).  The order of the BMP palette ppmtobmp generates is the order of the pixels in
              the palette file, going from top to bottom, left to right.

              A BMP palette may have at most 256 colors, so the palette file must have at most 256 pixels.

              You may find pnmcolormap useful in generating the palette file.  pamseq too.

              This option was new in Netpbm 10.45 (December 2008).





NOTES
       To  get  a faithful reproduction of the input image, the maxval of the input image must be 255.  If it is some-
       thing else, the colors in the BMP file may be slightly different from the colors in the input.

       Windows icons are not BMP files.  Use ppmtowinicon to create those.


SEE ALSO
       bmptoppm(1), ppmtowinicon(1), pnmquant(1), ppmdither(1), pnmremap(1), ppm(1)


AUTHOR
       Copyright (C) 1992 by David W. Sanderson.



netpbm documentation            29 October 2008        Ppmtobmp User Manual(0)