1 Reply Latest reply: Mar 9, 2010 12:41 PM by BenCloutier RSS

    PostScript Imagemask operator and ID preflight

    Lawrence Horwitz Community Member

      It appears that EPS images that use the PostScript "imagemask" operator are causing ID CS4's preflight feature to think they're lo-res.  You need to edit the preflight profile and enable the rule that checks image resolution to reproduce this.  If you take the following simple EPS and place it in InDesign, you'll see the problem:

       

      %!PS-Adobe-2.0 EPSF-2.0
      %%BoundingBox: 49 49 182 182
      %%EndComments
      %%EndProlog

       

      50 50 translate        % Locate lower-left corner of square
      120 120 scale          % Scale 1 unit to 120 points
      0 0 moveto 0 1 lineto  % Fill square with gray background
      1 1 lineto 1 0 lineto closepath
      .9 setgray fill
      0 setgray              % Paint mask black
      24 23                  % Dimensions of source mask
      true                   % Paint the 1 bits
      [24 0 0 -23 0 23]      % Map unit square to mask

       

      {<003B00 002700 002480 0E4940 114920 14B220 3CB650 75FE88 17FF8C 175F14
      1C07E2 3803C4 703182 F8EDFC B2BBC2 BB6F84 31BFC2 18EA3C 0E3E00 07FC00
      03F800 1E1800 1FF800>} % Mask data
      imagemask

       

      If you distill this to a PDF, the PDF renders fine in Acrobat, but pixelated in Apple's Preview app.

       

      Any insight?