plan9fox/sys/lib/ghostscript/viewpbm.ps

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% Copyright (C) 1992, 1995, 1996, 1998, 1999 Aladdin Enterprises. All rights reserved.
%
% This software is provided AS-IS with no warranty, either express or
% implied.
%
% This software is distributed under license and may not be copied,
% modified or distributed except as expressly authorized under the terms
% of the license contained in the file LICENSE in this distribution.
%
% For more information about licensing, please refer to
% http://www.ghostscript.com/licensing/. For information on
% commercial licensing, go to http://www.artifex.com/licensing/ or
% contact Artifex Software, Inc., 101 Lucas Valley Road #110,
% San Rafael, CA 94903, U.S.A., +1(415)492-9861.
% $Id: viewpbm.ps,v 1.5 2002/06/02 12:03:28 mpsuzuki Exp $
% viewpbm.ps
% Display a PBM/PGM/PPM file.
% Requires the Level 2 `image' operator (to handle variable pixel widths).
% If SCALE is defined, maps input pixels to output pixels with that scale;
% if SCALE is undefined, scales the image to fit the page.
/s 100 string def
/readmaxv { % <file> readmaxv -
10 string readline pop cvx exec /maxv exch def
} bind def
/readrow { % <file> <row> readrow <row>
0 1 2 index length 1 sub {
1 index exch 3 index token pop put
} for exch pop
} bind def
/read01 { % <file> <count> read01 <byte>
0 exch {
1 index read pop 48 xor dup 1 le { exch dup add add } { pop } ifelse
} repeat
} bind def
/readrow01 { % <file> <row> readrow01 <row>
0 1 w 8 idiv {
1 index exch 3 index 8 read01 put
} for
wrem 0 ne {
dup rsize 1 sub wrem read01 8 wrem sub bitshift put
} if
exch pop
} bind def
/readwh { % <file> readwh <w> <h>
dup s readline pop % check for comment
(#) anchorsearch {
pop pop dup s readline pop
} if
cvx exec
} bind def
/pbmtypes mark
% The procedures in this dictionary are called as
% <file> Pn <w> <h> <readproc>
/P1 { % ASCII 1-bit white/black
/bpc 1 def /maxv 1 def /rsize w 7 add 8 idiv def
/wrem w 8 mod def
/ncomp 1 def /invert true def /DeviceGray setcolorspace
readwh
{ readrow01 }
} bind
/P2 { % ASCII 8-bit gray
readwh
/bpc 8 def 2 index readmaxv /rsize 2 index def
/ncomp 1 def /invert false def /DeviceGray setcolorspace
{ readrow }
} bind
/P3 { % ASCII 8-bit RGB
readwh
/bpc 8 def 2 index readmaxv /rsize 2 index 3 mul def
/ncomp 3 def /invert false def /DeviceRGB setcolorspace
{ readrow }
} bind
/P4 { % Binary 1-bit white/black
readwh
/bpc 1 def /maxv 1 def /rsize 2 index 7 add 8 idiv def
/ncomp 1 def /invert true def /DeviceGray setcolorspace
{ readstring pop }
} bind
/P5 { % Binary 8-bit gray
readwh
/bpc 8 def 2 index readmaxv /rsize 2 index def
/ncomp 1 def /invert false def /DeviceGray setcolorspace
{ readstring pop }
} bind
/P6 { % Binary 8-bit RGB
readwh
/bpc 8 def 2 index readmaxv /rsize 2 index 3 mul def
/ncomp 3 def /invert false def /DeviceRGB setcolorspace
{ readstring pop }
} bind
.dicttomark readonly def
/pbmsetup { % <file> <w> <h> <readproc> runpbm -
/readproc exch def
/h exch def
/w exch def
/f exch def
20 dict begin % image dictionary
/ImageType 1 def
/Width w def
/Height h def
/ImageMatrix [w 0 0 h neg 0 h] def
/BitsPerComponent bpc def
/Decode [ 0 255 maxv div invert { exch } if ncomp 1 sub { 2 copy } repeat ] def
/DataSource [ f rsize string /readproc load /exec load ] cvx def
currentdict end
} def
/imagescale { % <imagedict> imagescale -
begin
/SCALE where {
pop
% Map pixels SCALE-for-1. Assume orthogonal transformation.
Width 1 0 dtransform add abs div SCALE mul
Height 0 1 dtransform add abs div SCALE mul
} {
% Scale the image (uniformly) to fit the page.
clippath pathbbox pop pop translate
pathbbox .min exch pop exch pop ceiling
dup Height Width gt {
Width mul Height div exch
} {
Height mul Width div
} ifelse
}
ifelse scale
end
} def
% Image a PBM file page by page.
/viewpbm { % <filename> viewpbm -
20 dict begin
(r) file /pf exch def {
pf token not { exit } if
pbmtypes exch get pf exch exec pbmsetup
dup imagescale image showpage
} loop
end
} def
% Reassemble a composite PBM file from the CMYK separations.
/viewpsm {
20 dict begin
/fname exch def
/sources [ 0 1 3 {
/plane exch def
/pf fname (r) file def
pf pbmtypes pf token pop get exec
% Stack: pf w h readproc
plane {
/readproc exch def /h exch def /w exch def pop
/row rsize string def
h { pf row readproc pop } repeat
pf pbmtypes pf token pop get exec
} repeat
pbmsetup
} for ] def
/datas [ sources { /DataSource get 0 get } forall ] def
/decode sources 0 get /Decode get
dup 0 get exch 1 get add cvi 0 exch
2 copy 4 copy 8 array astore def
sources 0 get
dup /MultipleDataSources true put
dup /DataSource datas put
dup /Decode decode put
/DeviceCMYK setcolorspace
dup imagescale image showpage
end
} def
% If the program was invoked from the command line, run it now.
[ shellarguments
{ counttomark 1 ge
{ ] { viewpbm } forall
}
{ cleartomark
(Usage: gs [--] viewpbm.ps filename.p*m ...\n) print
( e.g.: gs [--] viewpbm.ps my.ppm another.ppm\n) print flush
}
ifelse
}
{ pop
}
ifelse