ref: 565fc2be5df4288bf30edd86100b53a371223076
dir: /sys/lib/ghostscript/viewmiff.ps/
% Copyright (C) 1998 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: viewmiff.ps,v 1.4 2002/02/21 21:49:28 giles Exp $ % viewmiff.ps % Display a MIFF file. You would think the 'display' command would do this, % but many versions of 'display' either core-dump or require unacceptably % large amounts of memory. % Recognize MIFF keywords. /miffwords mark /class { cvn /class exch def } /colors { cvi /colors exch def } /columns { cvi /Width exch def } /compression { cvn /compression exch def } /depth { cvi /depth exch def } /packets { cvi /packets exch def } /rows { cvi /Height exch def } .dicttomark readonly def % Recognize MIFF image classes. /miffclasses mark /DirectClass { /DeviceRGB setcolorspace /BitsPerComponent depth def /Decode [ 0 1 0 1 0 1 ] def } /PseudoClass { [ /Indexed % The MIFF documentation lies about the size of pixels % for this case: the pixel size is determined only by % the number of colors, and is not affected by the image % depth. Specifically, if there are 256 or fewer colors % but the depth (of color map entries) is 16, each pixel % is still only 1 byte, not 2. currentdict /colors known { /DeviceRGB colors 1 sub /BitsPerComponent colors 256 le { 8 } { 16 } ifelse def colors 3 mul string depth 8 eq { f exch readstring pop } { % 16-bit color map entries: take only the high-order byte. 0 1 2 index length 1 sub { f read pop 2 index 3 1 roll put f read pop pop } for } ifelse } { /colors 256 def /DeviceGray 255 256 string 0 1 255 { 1 index exch dup put } for } ifelse ] setcolorspace /Decode [ 0 1 BitsPerComponent bitshift 1 sub ] def } .dicttomark readonly def % Recognize MIFF compression methods. /rlstring 768 string def /rlread { % packets is not reliable -- disregard it. dup rlstring 0 3 getinterval readstring { pop read pop 3 mul 3 3 2 index { rlstring exch rlstring 0 3 getinterval putinterval } for rlstring 0 3 -1 roll 3 add getinterval } { pop pop () } ifelse } bind def /miffcompress mark /Uncompressed { f } /RunLengthEncoded { { f rlread } } /Zip { [ f /FlateDecode filter cvlit /rlread cvx ] cvx } .dicttomark readonly def % Read a MIFF file and display the image. /viewmiff { % <filename> viewmiff - 50 dict begin /fname 1 index def /f exch (r) file def % Set defaults. /ImageType 1 def /class /DirectClass def /compression /Uncompressed def /depth 8 def /packets 16#7fffffff def % Read and parse the header. { f token pop dup (:) eq { pop exit } if dup type /nametype eq { .namestring (=) search { exch pop miffwords exch .knownget { exec } { pop } ifelse } { pop % who knows? } ifelse } { pop % probably a comment in braces } ifelse } loop % Read and display the image. miffclasses class get exec /DataSource miffcompress compression get exec def /ImageMatrix [Width 0 0 Height neg 0 Height] def currentpagedevice /PageSize get dup 0 get exch 1 get scale gsave 0.8 setgray 0 0 1 1 rectfill grestore % provide background currentdict image showpage % Clean up. f closefile end } bind def