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Pnmtopalm User Manual(0)			      Pnmtopalm	User Manual(0)

       pnmtopalm - convert a PNM image to a Palm Bitmap









       [-withdummy] [-scanline_compression | -rle_compression |	-packbits_com-


       Minimum unique abbreviation of option is	acceptable.  You may use  dou-
       ble  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.

       This program is part of Netpbm(1).

       pnmtopalm  reads	 a  PNM	image as input,	from Standard Input or pnmfile
       and produces a Palm Bitmap as output.

       Palm Bitmap files are either grayscale files with 1, 2, or 4  bits  per
       pixel,  or  mapped  color files with 8 bit per pixel, or	a direct color
       file with 16 bits per pixel, and	pnmtopalm  chooses  this  color	 depth
       based on	the maxval and number of colors	in the input, unless you spec-
       ify a depth (bits per pixel) with -depth.  You can also specify a maxi-
       mum  depth  with	 -maxdepth  to partially constrain pnmtopalm's choice.
       Input files must	have an	appropriate number and set of colors  for  the
       selected	output constraints.

       This  often means that you should run the PNM image through pnmquant or
       pnmremap	before you pass	it to pnmtopalm.  Netpbm  comes	 with  several
       colormap	 files	you  can use with pnmremap for this purpose.  They are (4	shades of gray for a depth of  2),  (16
       shades of gray for a depth of 4), and (232 colors	in de-
       fault Palm colormap).  In a standard Netpbm installation, these are  in
       the  Netpbm  data directory, and	you can	find the Netpbm	data directory
       with a netpbm-config --datadir shell command.


	 pnmremap myimage.ppm \
		  -mapfile=$(netpbm-config --datadir)/ \
	 | pnmtopalm -depth=2 >myimage.palm

       Compressed Palm Bitmap files, at	least the ones pnmtopalm knows how  to
       create,	cannot have more than 8	bits per pixel.	 pnmtopalm defaults to
       8 bits per pixel	if you specify a compressed output.  You  can  specify
       the number of bits per pixel explicitly with -depth.  -maxdepth has the
       same effect as -depth.  If you specify more than	8 bits per pixel  with
       either of these,	pnmtopalm fails.

   Palm	Bitmap Version
       pnmtopalm  generates a Version 0, 1, 2, or 3 Palm Bitmap.  It generates
       the oldest (lowest) version it can for the given	image and the  options
       you specify.

       o      If  you  specify	a density (-density option) higher than	"low,"
	      the version is at	least 3.

       o      If you specify transparency (-transparent	option)	 or  any  com-
	      pression,	the version is at least	2.

       o      If you specify a custom colormap (-colormap option), the version
	      is at least 1.

       o      If the image has more than one bit per pixel, the	version	is  at
	      least 1.	The image has more than	one bit	per pixel if you spec-
	      ify it with -depth or if you let it default and  the  image  has
	      more than	two colors (or shades of gray).

       All  releases  of Palm OS can read a Version 0 bitmap.  Palm OS 3.0 and
       later can read a	Version	1 bitmap.  Palm	OS 3.5 and later  can  read  a
       Version	2 bitmap.  To read a Version 3 bitmap, you need	Palm OS	Garnet
       or a handheld running the High Density Display Feature Set.

	      Display the format of the	output file.

	      Produce a	file of	depth N, where N must be either	1, 2, 4, 8, or
	      16.   Because  the default Palm 8-bit colormap is	not grayscale,
	      if the input is a	grayscale or monochrome	image, the output will
	      never  be	 more  than  4	bits deep, regardless of the specified
	      depth.  Note that	8-bit color works  only	 in  PalmOS  3.5  (and
	      higher),	and  16-bit direct color works only in PalmOS 4.0 (and
	      higher).	However, the 16-bit direct color format	is  also  com-
	      patible  with  the various PalmOS	3.x versions used in the Hand-
	      spring Visor, so these images may	also work in that device.

	      Produce a	file of	minimal	depth, but in any  case	 less  than  N
	      bits  wide.   If	you  specify 16-bit, the output	will always be
	      16-bit direct color.

	      Set the nextDepthOffset field in the palm	file header  to	 indi-
	      cate  the	 end  of  the  file  (and pad the end of the file to 4
	      bytes, since nextDepthOffset can point only  to  4  byte	bound-

	      A	 palm  image  file can contain multiple	renditions of the same
	      image, with different color depths, so a viewer can  choose  one
	      appropriate  for	the  display.  The nextDepthOffset field tells
	      where in the stream the next rendition begins.

	      pnmtopalm	creates	a file that contains only one image,  but  you
	      can  separately concatenate multiple one-image files to create a
	      multi-image file.	 If you	do that, you'll	need to	use -offset so
	      that the resulting concatenation is a correct stream.

	      By default (if you don't specify -offset), pnmtopalm generates a
	      nextDepthOffset field that says there is no following image (and
	      does not add any padding after the image).

	      Version  3  Palm	Bitmaps	actually have a	nextBitmapOffset field
	      instead of the nextDepthOffset.  The foregoing applies to	which-
	      ever is relevant.

	      The  -offset option was new in Netpbm 10.26 (January 2005).  Be-
	      fore that, pnmtopalm always set  the  nextDepthOffset  field  to

	      Before  Netpbm 10.27 (March 2005), you cannot use	-offset	if you
	      create a compressed raster (because pnmtopalm isn't smart	enough
	      to  be  able to know the size of the image at the	time it	writes
	      the header).  You	also cannot use	it with	16 bit color depth  or
	      with the -colormap option, for much the same reason.

	      This  option tells pnmtopalm to put in the stream, after the im-
	      age, a dummy image header	to introduce subsequent	 high  density

	      This  dummy image	header is a special sequence specified in Palm
	      Bitmap specifications.  It looks to an older Palm	Bitmap	inter-
	      preter like an invalid image header, so such an interpreter will
	      stop reading the stream there.  But a  new  Palm	Bitmap	inter-
	      preter  recognizes it for	what it	is (just something to choke an
	      old interpreter) and skips over it.  Presumably, you will	add to
	      the stream after this high density images	which would confuse an
	      older interpreter.

	      If you specify -withdummy, you must also specify -offset,	 since
	      it doesn't make any sense	otherwise.

	      -withdummy was new in Netpbm 10.27 (March	2005).

	      Build a custom colormap and include it in	the output file.  This
	      is not recommended by Palm, for efficiency reasons.   Otherwise,
	      pnmtopalm	uses the default Palm colormap for color output.

	      Marks one	particular color as fully transparent.

	      colorspec	  is   as   described	for   the   argument   of  the
	      pnm_parsecolor()		       library		       routine
	      <libnetpbm_image.html#colorname> .

	      Transparency works only on Palm OS 3.5 and higher.

	      Specifies	that the output	Palm bitmap will use the Palm scanline
	      compression scheme.  Scanline compression	works only in Palm  OS
	      2.0 and higher.

	      Specifies	that the output	Palm bitmap will use the Palm RLE com-
	      pression scheme.	RLE compression	works only with	 Palm  OS  3.5
	      and higher.

	      Specifies	that the output	Palm bitmap will use the Palm packbits
	      compression scheme.  Packbits compression	works only  with  Palm
	      OS 4.0 and higher.

	      This option was new in Netpbm 10.27 (March 2005).

	      This specifies the Palm Bitmap density.  The density is a	number
	      that is proportional to the resolution  the  image  should  have
	      when displayed.  The proportionality factor is up	to whatever is
	      doing the	displaying, but	it's helpful to	think of these numbers
	      as being pixels per inch.	 The allowable values are:

       o      72

       o      108

       o      144

       o      216

       o      288

	      This  option  was	 new  in  Netpbm  10.27	(March 2005).  Earlier
	      Netpbm could not generate	Version	3 Palm Bitmaps,	so  there  was
	      no such thing as density.

       palmtopnm(1), pdbimgtopam(1), pnmquant(1), pnmremap(1), pnm(5)

       Palm  Bitmaps  may  contains multiple renditions	of the same bitmap, in
       different depths.  To construct	an  N-multiple-rendition  Palm	Bitmap
       with  pnmtopalm,	 first	construct  renditions  1 through N-1 using the
       -offset option, then construct the Nth image without  the  -offset  op-
       tion.   Then concatenate	the individual renditions together in a	single
       file using cat.

       If you will include both	high density and low density  renditions,  put
       the  high  density  images last and when	you create the last of the low
       density images, use the -withdummy option.

       If you specify the Palm packbits	compression scheme for a 16-bit	direct
       color bitmap, this program generates an invalid bitmap.

       This program was	originally written as ppmtoTbmp.c, by Ian Goldberg and
       George Caswell.	It was completely re-written by	Bill  Janssen  to  add
       color,  compression, and	transparency function.	Copyright 1995-2001 by
       Ian Goldberg, George Caswell, and Bill Janssen.

       This manual page	was generated by the Netpbm tool 'makeman'  from  HTML
       source.	The master documentation is at

netpbm documentation		25 August 2017	      Pnmtopalm	User Manual(0)


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