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Edit File: viewcmyk.ps

% Copyright (C) 2001-2018 Artifex Software, Inc.
% 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.
%
% Refer to licensing information at http://www.artifex.com or contact
% Artifex Software, Inc.,  1305 Grant Avenue - Suite 200, Novato,
% CA 94945, U.S.A., +1(415)492-9861, for further information.
%

% viewcmyk.ps
% Display a raw CMYK file.
% Requires the colorimage operator.
% If SCALE is defined, maps input pixels to output pixels with that scale;
% if SCALE is undefined, scales the image to fit the page.
% If BITS is defined, it is the number of bits per sample (1,2,4,8,12);
% if BITS is undefined, its default value is 1.

/viewcmyk {			% <filename> <width> viewcmyk -
  20 dict begin
  /w exch def
  /fname exch def
  /bpc /BITS where { pop BITS } { 1 } ifelse def
  /f fname (r) file def
  mark fname status pop pop pop /flen exch def cleartomark
  /h flen w bpc 4 mul mul 7 add 8 idiv idiv def
  (Dimensions: ) print [w h] == flush
                % Set up scaling.
  /SCALE where {
    pop
        % Map pixels SCALE-for-1.  Assume orthogonal transformation.
    SCALE 1 0 dtransform add abs div
    SCALE 0 1 dtransform add abs div
  } {
        % Scale the image (uniformly) to fit the page.
    clippath pathbbox pop pop translate
    pathbbox 3 -1 roll sub h div
    3 1 roll exch sub w div .min dup
  } ifelse scale
  w h bpc [1 0 0 -1 0 h] f false 4 colorimage
  showpage
  f closefile
  end
} bind def

% If the program was invoked from the command line, run it now.
[ shellarguments {
  counttomark 2 eq {
    cvi viewcmyk
  } {
    cleartomark
    (Usage: gs -- viewcmyk.ps filename.cmyk width\n) print
    ( e.g.: gs -- viewcmyk.ps my.cmyk 2550\n) print flush
  } ifelse
} {
  pop
} ifelse