1Pnmtopalm User Manual(0)                              Pnmtopalm User Manual(0)
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NAME

6       pnmtopalm - convert a PNM image to a Palm Bitmap
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8

SYNOPSIS

10       pnmtopalm
11
12       [-verbose]
13
14       [-depth=N]
15
16       [-maxdepth=N]
17
18       [-colormap]
19
20       [-transparent=colorspec]
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22       [-density=N]
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24       [-offset]
25
26       [-withdummy] [-scanline_compression | -rle_compression | -packbits_com‐
27       pression]
28
29       [pnmfile]
30
31       Minimum unique abbreviation of option is acceptable.  You may use  dou‐
32       ble  hyphens  instead  of single hyphen to denote options.  You may use
33       white space in place of the equals sign to separate an option name from
34       its value.
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36

DESCRIPTION

38       This program is part of Netpbm(1).
39
40       pnmtopalm  reads  a  PNM image as input, from Standard Input or pnmfile
41       and produces a Palm Bitmap as output.
42
43       Palm Bitmap files are either grayscale files with 1, 2, or 4  bits  per
44       pixel,  or  mapped  color files with 8 bit per pixel, or a direct color
45       file with 16 bits per pixel, and pnmtopalm  chooses  this  color  depth
46       based on the maxval and number of colors in the input, unless you spec‐
47       ify a depth (bits per pixel) with -depth.  You can also specify a maxi‐
48       mum  depth  with  -maxdepth  to partially constrain pnmtopalm's choice.
49       Input files must have an appropriate number and set of colors  for  the
50       selected output constraints.
51
52       This  often means that you should run the PNM image through pnmquant or
53       pnmremap before you pass it to pnmtopalm.  Netpbm  comes  with  several
54       colormap  files  you  can use with pnmremap for this purpose.  They are
55       palmgray2.map (4 shades of gray for a depth of  2),  palmgray4.map  (16
56       shades  of  gray  for  a depth of 4), and palmcolor8.map (232 colors in
57       default Palm colormap).  In a standard Netpbm installation,  these  are
58       in  the  Netpbm data directory, and you can find the Netpbm data direc‐
59       tory with a netpbm-config --datadir shell command.
60
61       Example:
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63         pnmremap myimage.ppm \
64                  -mapfile=$(netpbm-config --datadir)/palmgray2.map \
65         | pnmtopalm -depth=2 >myimage.palm
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67
68       Compressed Palm Bitmap files, at least the ones pnmtopalm knows how  to
69       create,  cannot have more than 8 bits per pixel.  pnmtopalm defaults to
70       8 bits per pixel if you specify a compressed output.  You  can  specify
71       the number of bits per pixel explicitly with -depth.  -maxdepth has the
72       same effect as -depth.  If you specify more than 8 bits per pixel  with
73       either of these, pnmtopalm fails.
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75
76
77   Palm Bitmap Version
78       pnmtopalm  generates a Version 0, 1, 2, or 3 Palm Bitmap.  It generates
79       the oldest (lowest) version it can for the given image and the  options
80       you specify.
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82
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84       ·      If  you  specify  a density (-density option) higher than "low,"
85              the version is at least 3.
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87
88       ·      If you specify transparency (-transparent option)  or  any  com‐
89              pression, the version is at least 2.
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92       ·      If you specify a custom colormap (-colormap option), the version
93              is at least 1.
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95
96       ·      If the image has more than one bit per pixel, the version is  at
97              least 1.  The image has more than one bit per pixel if you spec‐
98              ify it with -depth or if you let it default and  the  image  has
99              more than two colors (or shades of gray).
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101
102
103       All  releases  of Palm OS can read a Version 0 bitmap.  Palm OS 3.0 and
104       later can read a Version 1 bitmap.  Palm OS 3.5 and later  can  read  a
105       Version  2 bitmap.  To read a Version 3 bitmap, you need Palm OS Garnet
106       or a handheld running the High Density Display Feature Set.
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108

OPTIONS

110       -verbose
111              Display the format of the output file.
112
113
114       -depth=N
115              Produce a file of depth N, where N must be either 1, 2, 4, 8, or
116              16.   Because  the default Palm 8-bit colormap is not grayscale,
117              if the input is a grayscale or monochrome image, the output will
118              never  be  more  than  4  bits deep, regardless of the specified
119              depth.  Note that 8-bit color works  only  in  PalmOS  3.5  (and
120              higher),  and  16-bit direct color works only in PalmOS 4.0 (and
121              higher).  However, the 16-bit direct color format is  also  com‐
122              patible  with  the various PalmOS 3.x versions used in the Hand‐
123              spring Visor, so these images may also work in that device.
124
125
126       -maxdepth=N
127              Produce a file of minimal depth, but in any  case  less  than  N
128              bits  wide.   If  you  specify 16-bit, the output will always be
129              16-bit direct color.
130
131
132       -offset
133              Set the nextDepthOffset field in the palm file header  to  indi‐
134              cate  the  end  of  the  file  (and pad the end of the file to 4
135              bytes, since nextDepthOffset can point only  to  4  byte  bound‐
136              aries).
137
138              A  palm  image  file can contain multiple renditions of the same
139              image, with different color depths, so a viewer can  choose  one
140              appropriate  for  the  display.  The nextDepthOffset field tells
141              where in the stream the next rendition begins.
142
143              pnmtopalm creates a file that contains only one image,  but  you
144              can  separately concatenate multiple one-image files to create a
145              multi-image file.  If you do that, you'll need to use -offset so
146              that the resulting concatenation is a correct stream.
147
148              By default (if you don't specify -offset), pnmtopalm generates a
149              nextDepthOffset field that says there is no following image (and
150              does not add any padding after the image).
151
152              Version  3  Palm  Bitmaps actually have a nextBitmapOffset field
153              instead of the nextDepthOffset.  The foregoing applies to which‐
154              ever is relevant.
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156              The  -offset  option  was  new  in  Netpbm 10.26 (January 2005).
157              Before that, pnmtopalm always set the nextDepthOffset  field  to
158              "none."
159
160              Before  Netpbm 10.27 (March 2005), you cannot use -offset if you
161              create a compressed raster (because pnmtopalm isn't smart enough
162              to  be  able to know the size of the image at the time it writes
163              the header).  You also cannot use it with 16 bit color depth  or
164              with the -colormap option, for much the same reason.
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166
167       -withdummy
168              This  option  tells  pnmtopalm  to  put in the stream, after the
169              image, a dummy image header to introduce subsequent high density
170              images.
171
172              This  dummy image header is a special sequence specified in Palm
173              Bitmap specifications.  It looks to an older Palm Bitmap  inter‐
174              preter like an invalid image header, so such an interpreter will
175              stop reading the stream there.  But a  new  Palm  Bitmap  inter‐
176              preter  recognizes it for what it is (just something to choke an
177              old interpreter) and skips over it.  Presumably, you will add to
178              the stream after this high density images which would confuse an
179              older interpreter.
180
181              If you specify -withdummy, you must also specify -offset,  since
182              it doesn't make any sense otherwise.
183
184              -withdummy was new in Netpbm 10.27 (March 2005).
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186
187       -colormap
188              Build a custom colormap and include it in the output file.  This
189              is not recommended by Palm, for efficiency reasons.   Otherwise,
190              pnmtopalm uses the default Palm colormap for color output.
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192
193       -transparent=colorspec
194              Marks one particular color as fully transparent.
195
196              colorspec   is   as   described   for   the   argument   of  the
197              ppm_parsecolor() library routine ⟨libppm.html#colorname⟩ .
198
199              Transparency works only on Palm OS 3.5 and higher.
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201
202       -scanline_compression
203              Specifies that the output Palm bitmap will use the Palm scanline
204              compression  scheme.  Scanline compression works only in Palm OS
205              2.0 and higher.
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207
208       -rle_compression
209              Specifies that the output Palm bitmap will use the Palm RLE com‐
210              pression  scheme.   RLE  compression works only with Palm OS 3.5
211              and higher.
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213
214       -packbits_compression
215              Specifies that the output Palm bitmap will use the Palm packbits
216              compression  scheme.   Packbits compression works only with Palm
217              OS 4.0 and higher.
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219              This option was new in Netpbm 10.27 (March 2005).
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221
222       -density=N
223              This specifies the Palm Bitmap density.  The density is a number
224              that  is  proportional  to  the resolution the image should have
225              when displayed.  The proportionality factor is up to whatever is
226              doing the displaying, but it's helpful to think of these numbers
227              as being pixels per inch.  The allowable values are:
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229
230
231       ·      72
232
233       ·      108
234
235       ·      144
236
237       ·      216
238
239       ·      288
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241
242              This option was new  in  Netpbm  10.27  (March  2005).   Earlier
243              Netpbm  could  not generate Version 3 Palm Bitmaps, so there was
244              no such thing as density.
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SEE ALSO

251       palmtopnm(1), pdbimgtopam(1), pnmquant(1), pnmremap(1), pnm(1)
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NOTES

256       Palm Bitmaps may contains multiple renditions of the  same  bitmap,  in
257       different  depths.   To  construct  an N-multiple-rendition Palm Bitmap
258       with pnmtopalm, first construct renditions  1  through  N-1  using  the
259       -offset  option,  then  construct  the  Nth  image  without the -offset
260       option.  Then concatenate the individual renditions together in a  sin‐
261       gle file using cat.
262
263       If  you  will include both high density and low density renditions, put
264       the high density images last and when you create the last  of  the  low
265       density images, use the -withdummy option.
266
267       If you specify the Palm packbits compression scheme for a 16-bit direct
268       color bitmap, this program generates an invalid bitmap.
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271

AUTHORS

273       This program was originally written as ppmtoTbmp.c, by Ian Goldberg and
274       George  Caswell.   It  was completely re-written by Bill Janssen to add
275       color, compression, and transparency function.  Copyright 1995-2001  by
276       Ian Goldberg, George Caswell, and Bill Janssen.
277

DOCUMENT SOURCE

279       This  manual  page was generated by the Netpbm tool 'makeman' from HTML
280       source.  The master documentation is at
281
282              http://netpbm.sourceforge.net/doc/pnmtopalm.html
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284netpbm documentation            25 August 2017        Pnmtopalm User Manual(0)
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