ppmtoilbm(1)

1Ppmtoilbm User Manual(0)                              Ppmtoilbm User Manual(0)
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NAME

6       ppmtoilbm - convert a PPM image into an ILBM file
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SYNOPSIS

10       ppmtoilbm
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12       [-maxplanes|-mp N]
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14       [-fixplanes|-fp N]
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16       [-ham6|-ham8]
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18       [{-dcbits|-dcplanes} r g b]
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20       [ -normal|-hamif|-hamforce|-24if|-24force| -dcif|-dcforce|-cmaponly ]
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22       [-ecs|-aga]
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24       [-compress|-nocompress]
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26       [-cmethod type]
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28       [-map ppmfile]
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30       [-savemem]
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32       [ppmfile]
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DESCRIPTION

36       This program is part of Netpbm(1).
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38       ppmtoilbm reads a PPM image as input.  Produces an ILBM file as output.
39       ppmtoilbm understands the following ILBM types:
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44       ·      Normal ILBMs with 1-16 planes
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47       ·      Amiga HAM with 3-16 planes
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50       ·      24 bit
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53       ·      Color map (BMHD + CMAP chunk only, nPlanes = 0)
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56       ·      Unofficial direct color.  1-16 planes for each color component.
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60       Chunks written: BMHD, CMAP, CAMG (only for HAM), BODY (not for colormap
61       files) unofficial DCOL chunk for direct color ILBM.
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OPTIONS

65       Options  marked  with (*) can be prefixed with a 'no', e.g. '-nohamif'.
66       All options can be abbreviated to their shortest unique prefix.
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70       -maxplanes | -mp n
71              (default 5, minimum 1, maximum 16) Maximum planes to write in  a
72              normal  ILBM.   If  the image does not fit into <n> planes, ppm‐
73              toilbm writes a HAM file (if -hamif is used), a 24bit  file  (if
74              -24if  is  used)  or  a  direct color file (if -dcif is used) or
75              aborts with an error.
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78       -fixplanes | -fp b
79              (min 1, max 16) If a  normal  ILBM  is  written,  it  will  have
80              exactly <n> planes.
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83       -hambits | -hamplanes n
84              (default  6, min 3, max 16) Select number of planes for HAM pic‐
85              ture.  The current Amiga hardware supports 6 and  8  planes,  so
86              for now you should only use this values.
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89       -normal
90              Turns  off  -hamif/-24if/-dcif,  -hamforce/-24force/-dcforce and
91              -cmaponly.  Also sets compression type to byterun1.
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93              This is the default.
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96       -hamif (*)
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98       -24if (*)
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100       -dcif (*)
101              Write a HAM/24bit/direct color file if the image  does  not  fit
102              into <maxplanes> planes.
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105       -hamforce (*)
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107       -24force (*)
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109       -dcforce (*)
110              Write a HAM/24bit/direct color file.
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113       -dcbits r g b
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115       -dcplanes r g b
116              (default  5,  min  1,  max  16).  Select number of bits for red,
117              green and blue in a direct color ILBM.
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120       -ecs   Shortcut for: -hamplanes 6 -maxplanes 5
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122              This is the default.
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125       -aga   Shortcut for: -hamplanes 8 -maxplanes 8
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128       -ham6  Shortcut for: -hamplanes 6 -hamforce
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131       -ham8  Shortcut for: -hamplanes 8 -hamforce
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134       -compress (*)
135              This is the default.  Compress the BODY chunk.  The default com‐
136              pression  method is byterun1.  Compression requires building the
137              ILBM image in memory; turning  compression  off  allows  stream-
138              writing of the image, but the resulting file will usually be 30%
139              to 50% larger.  Another alternative is the -savemem option, this
140              will  keep memory requirements for compression at a minimum, but
141              is very slow.
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144       -cmethod none|byterun1
145              This option does the same thing as -compress.
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148       -map ppmfile
149              Write a normal ILBM using the colors in <ppmfile>  as  the  col‐
150              ormap.   The colormap file also determines the number of planes,
151              a -maxplanes or -fixplanes option is ignored.
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154       -cmaponly
155              Write a colormap file: only BMHD and CMAP chunks, no BODY chunk,
156              nPlanes = 0.
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159       -savemem
160              See the -compress option.
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LIMITATIONS

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

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

184       Copyright (C) 1989 by Jef Poskanzer.
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186       Modified October 1993 by Ingo Wilken (Ingo.Wilken@informatik.uni-olden‐
187       burg.de)
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191netpbm documentation            31 October 1993       Ppmtoilbm User Manual(0)