Ppmtoilbm User Manual(0)                              Ppmtoilbm User Manual(0)



NAME
       ppmtoilbm - convert a PPM image into an ILBM file


SYNOPSIS
       ppmtoilbm

       [-maxplanes|-mp N]

       [-fixplanes|-fp N]

       [-ham6|-ham8]

       [{-dcbits|-dcplanes} r g b]

       [ -normal|-hamif|-hamforce|-24if|-24force| -dcif|-dcforce|-cmaponly ]

       [-ecs|-aga]

       [-compress|-nocompress]

       [-cmethod type]

       [-map ppmfile]

       [-savemem]

       [ppmfile]


DESCRIPTION
       This program is part of Netpbm(1)

       ppmtoilbm reads a PPM image as input.  Produces an ILBM file as output.
       ppmtoilbm understands the following ILBM types:




       o      Normal ILBMs with 1-16 planes


       o      Amiga HAM with 3-16 planes


       o      24 bit


       o      Color map (BMHD + CMAP chunk only, nPlanes = 0)


       o      Unofficial direct color.  1-16 planes for each color component.



       Chunks written: BMHD, CMAP, CAMG (only for HAM), BODY (not for colormap
       files) unofficial DCOL chunk for direct color ILBM.


OPTIONS
       Options marked with (*) can be prefixed with a 'no', e.g. '-nohamif'.
       All options can be abbreviated to their shortest unique prefix.



       -maxplanes | -mp n
              (default 5, minimum 1, maximum 16) Maximum planes to write in a
              normal ILBM.  If the image does not fit into <n> planes,
              ppmtoilbm writes a HAM file (if -hamif is used), a 24bit file
              (if -24if is used) or a direct color file (if -dcif is used) or
              aborts with an error.


       -fixplanes | -fp b
              (min 1, max 16) If a normal ILBM is written, it will have
              exactly <n> planes.


       -hambits | -hamplanes n
              (default 6, min 3, max 16) Select number of planes for HAM
              picture.  The current Amiga hardware supports 6 and 8 planes, so
              for now you should only use this values.


       -normal
              Turns off -hamif/-24if/-dcif, -hamforce/-24force/-dcforce and
              -cmaponly.  Also sets compression type to byterun1.

              This is the default.


       -hamif (*)

       -24if (*)

       -dcif (*)
              Write a HAM/24bit/direct color file if the image does not fit
              into <maxplanes> planes.


       -hamforce (*)

       -24force (*)

       -dcforce (*)
              Write a HAM/24bit/direct color file.


       -dcbits r g b

       -dcplanes r g b
              (default 5, min 1, max 16).  Select number of bits for red,
              green and blue in a direct color ILBM.


       -ecs   Shortcut for: -hamplanes 6 -maxplanes 5

              This is the default.


       -aga   Shortcut for: -hamplanes 8 -maxplanes 8


       -ham6  Shortcut for: -hamplanes 6 -hamforce


       -ham8  Shortcut for: -hamplanes 8 -hamforce


       -compress (*)
              This is the default.  Compress the BODY chunk.  The default
              compression method is byterun1.  Compression requires building
              the ILBM image in memory; turning compression off allows stream-
              writing of the image, but the resulting file will usually be 30%
              to 50% larger.  Another alternative is the -savemem option, this
              will keep memory requirements for compression at a minimum, but
              is very slow.


       -cmethod none|byterun1
              This option does the same thing as -compress.


       -map ppmfile
              Write a normal ILBM using the colors in <ppmfile> as the
              colormap.  The colormap file also determines the number of
              planes, a -maxplanes or -fixplanes option is ignored.


       -cmaponly
              Write a colormap file: only BMHD and CMAP chunks, no BODY chunk,
              nPlanes = 0.


       -savemem
              See the -compress option.





LIMITATIONS
       HAM pictures will always get a grayscale colormap; a real color
       selection algorithm might give better results.  On the other hand, this
       allows row-by-row operation on HAM images, and all HAM images of the
       same depth (no. of planes) share a common colormap, which is useful for
       building HAM animations.


REFERENCES
       Amiga ROM Kernel Reference Manual - Devices (3rd Ed.)  Addison Wesley,
       ISBN 0-201-56775-X


SEE ALSO
       ppm(5) , ilbmtoppm(1)



AUTHORS
       Copyright (C) 1989 by Jef Poskanzer.

       Modified October 1993 by Ingo Wilken (Ingo.Wilken@informatik.uni-
       oldenburg.de)

netpbm documentation            31 October 1993       Ppmtoilbm User Manual(0)