1Pnmtopalm User Manual(0)                              Pnmtopalm User Manual(0)
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3
4

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]
21
22       [-density=N]
23
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.
35
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 de‐
57       fault Palm colormap).  In a standard Netpbm installation, these are  in
58       the  Netpbm  data directory, and you can find the Netpbm data directory
59       with a netpbm-config --datadir shell command.
60
61       Example:
62
63         pnmremap myimage.ppm \
64                  -mapfile=$(netpbm-config --datadir)/palmgray2.map \
65         | pnmtopalm -depth=2 >myimage.palm
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67
68
69       Compressed Palm Bitmap files, at least the ones pnmtopalm knows how  to
70       create,  cannot have more than 8 bits per pixel.  pnmtopalm defaults to
71       8 bits per pixel if you specify a compressed output.  You  can  specify
72       the number of bits per pixel explicitly with -depth.  -maxdepth has the
73       same effect as -depth.  If you specify more than 8 bits per pixel  with
74       either of these, pnmtopalm fails.
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
83
84       •      If  you  specify  a density (-density option) higher than "low,"
85              the version is at least 3.
86
87
88       •      If you specify transparency (-transparent option)  or  any  com‐
89              pression, the version is at least 2.
90
91
92       •      If you specify a custom colormap (-colormap option), the version
93              is at least 1.
94
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       In addition to the options common to all programs  based  on  libnetpbm
111       (most notably -quiet, see
112        Common  Options ⟨index.html#commonoptions⟩ ), pnmtopalm recognizes the
113       following command line options:
114
115
116
117       -verbose
118              Display the format of the output file.
119
120
121       -depth=N
122              Produce a file of depth N, where N must be either 1, 2, 4, 8, or
123              16.   Because  the default Palm 8-bit colormap is not grayscale,
124              if the input is a grayscale or monochrome image, the output will
125              never  be  more  than  4  bits deep, regardless of the specified
126              depth.  Note that 8-bit color works  only  in  PalmOS  3.5  (and
127              higher),  and  16-bit direct color works only in PalmOS 4.0 (and
128              higher).  However, the 16-bit direct color format is  also  com‐
129              patible  with  the various PalmOS 3.x versions used in the Hand‐
130              spring Visor, so these images may also work in that device.
131
132
133       -maxdepth=N
134              Produce a file of minimal depth, but in any  case  less  than  N
135              bits  wide.   If  you  specify 16-bit, the output will always be
136              16-bit direct color.
137
138
139       -offset
140              Set the nextDepthOffset field in the palm file header  to  indi‐
141              cate  the  end  of  the  file  (and pad the end of the file to 4
142              bytes, since nextDepthOffset can point only  to  4  byte  bound‐
143              aries).
144
145              A  palm  image  file can contain multiple renditions of the same
146              image, with different color depths, so a viewer can  choose  one
147              appropriate  for  the  display.  The nextDepthOffset field tells
148              where in the stream the next rendition begins.
149
150              pnmtopalm creates a file that contains only one image,  but  you
151              can  separately concatenate multiple one-image files to create a
152              multi-image file.  If you do that, you'll need to use -offset so
153              that the resulting concatenation is a correct stream.
154
155              By default (if you don't specify -offset), pnmtopalm generates a
156              nextDepthOffset field that says there is no following image (and
157              does not add any padding after the image).
158
159              Version  3  Palm  Bitmaps actually have a nextBitmapOffset field
160              instead of the nextDepthOffset.  The foregoing applies to which‐
161              ever is relevant.
162
163              The  -offset option was new in Netpbm 10.26 (January 2005).  Be‐
164              fore that, pnmtopalm always set  the  nextDepthOffset  field  to
165              "none."
166
167              Before  Netpbm 10.27 (March 2005), you cannot use -offset if you
168              create a compressed raster (because pnmtopalm isn't smart enough
169              to  be  able to know the size of the image at the time it writes
170              the header).  You also cannot use it with 16 bit color depth  or
171              with the -colormap option, for much the same reason.
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173
174       -withdummy
175              This  option tells pnmtopalm to put in the stream, after the im‐
176              age, a dummy image header to introduce subsequent  high  density
177              images.
178
179              This  dummy image header is a special sequence specified in Palm
180              Bitmap specifications.  It looks to an older Palm Bitmap  inter‐
181              preter like an invalid image header, so such an interpreter will
182              stop reading the stream there.  But a  new  Palm  Bitmap  inter‐
183              preter  recognizes it for what it is (just something to choke an
184              old interpreter) and skips over it.  Presumably, you will add to
185              the stream after this high density images which would confuse an
186              older interpreter.
187
188              If you specify -withdummy, you must also specify -offset,  since
189              it doesn't make any sense otherwise.
190
191              -withdummy was new in Netpbm 10.27 (March 2005).
192
193
194       -colormap
195              Build a custom colormap and include it in the output file.  This
196              is not recommended by Palm, for efficiency reasons.   Otherwise,
197              pnmtopalm uses the default Palm colormap for color output.
198
199
200       -transparent=colorspec
201              Marks one particular color as fully transparent.
202
203              colorspec   is   as   described   for   the   argument   of  the
204              pnm_parsecolor()                 library                 routine
205              ⟨libnetpbm_image.html#colorname⟩ .
206
207              Transparency works only on Palm OS 3.5 and higher.
208
209
210       -scanline_compression
211              Specifies that the output Palm bitmap will use the Palm scanline
212              compression scheme.  Scanline compression works only in Palm  OS
213              2.0 and higher.
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215
216       -rle_compression
217              Specifies that the output Palm bitmap will use the Palm RLE com‐
218              pression scheme.  RLE compression works only with  Palm  OS  3.5
219              and higher.
220
221
222       -packbits_compression
223              Specifies that the output Palm bitmap will use the Palm packbits
224              compression scheme.  Packbits compression works only  with  Palm
225              OS 4.0 and higher.
226
227              This option was new in Netpbm 10.27 (March 2005).
228
229
230       -density=N
231              This specifies the Palm Bitmap density.  The density is a number
232              that is proportional to the resolution  the  image  should  have
233              when displayed.  The proportionality factor is up to whatever is
234              doing the displaying, but it's helpful to think of these numbers
235              as being pixels per inch.  The allowable values are:
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237
238
239       •      72
240
241       •      108
242
243       •      144
244
245       •      216
246
247       •      288
248
249
250              This  option  was  new  in  Netpbm  10.27 (March 2005).  Earlier
251              Netpbm could not generate Version 3 Palm Bitmaps, so  there  was
252              no such thing as density.
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256

SEE ALSO

258       palmtopnm(1), pdbimgtopam(1), pnmquant(1), pnmremap(1), pnm(1)
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260

NOTES

262       Palm  Bitmaps  may  contains multiple renditions of the same bitmap, in
263       different depths.  To construct  an  N-multiple-rendition  Palm  Bitmap
264       with  pnmtopalm,  first  construct  renditions  1 through N-1 using the
265       -offset option, then construct the Nth image without  the  -offset  op‐
266       tion.   Then concatenate the individual renditions together in a single
267       file using cat.
268
269       If you will include both high density and low density  renditions,  put
270       the  high  density  images last and when you create the last of the low
271       density images, use the -withdummy option.
272
273       If you specify the Palm packbits compression scheme for a 16-bit direct
274       color bitmap, this program generates an invalid bitmap.
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277

AUTHORS

279       This program was originally written as ppmtoTbmp.c, by Ian Goldberg and
280       George Caswell.  It was completely re-written by Bill  Janssen  to  add
281       color,  compression, and transparency function.  Copyright 1995-2001 by
282       Ian Goldberg, George Caswell, and Bill Janssen.
283

DOCUMENT SOURCE

285       This manual page was generated by the Netpbm tool 'makeman'  from  HTML
286       source.  The master documentation is at
287
288              http://netpbm.sourceforge.net/doc/pnmtopalm.html
289
290netpbm documentation            25 August 2017        Pnmtopalm User Manual(0)
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