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% Copyright (C) 2001-2020 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.
%
% helper file to simplify use of Stochastic Halftone - uses ht_ccsto.ps
% This file sets the /StochasticDefault /Halftone as the current
% and the /Default halftoning, loading the Stochastic halftone
% if required.
% Stochastic halftoning is recommended for inkjet printers, and may
% produce output as pleasing as the more computationally expensive
% "error diffusion" that *some* device drivers provide.
% For printing technologies other than inkjet, Stochastic halftoning
% may not look better than standard screening. In particular, thermal
% transfer and direct thermal tend to be better with standard ordered
% screening methods. Some laser printers may produce "smoother"
% looking gray shades with Stochastic halftoning. Try it, and if
% you like it, use it.
% Note that this /Default halftone can be overridden by PostScript
% operators that set the screening or halftone (such as setscreen).
% To make Stochastic Halftone be "sticky" so that other screening and
% halftone setting in the subsequent PostScript will be ignored, use:
% -c "<< /HalftoneMode 1 >> setuserparams"
% on the command line prior to the file to be processed. For example,
%
% gs stocht.ps -c "<< /HalftoneMode 1 >> setuserparams" -f examples/tiger.eps
% Alternatively, the command to set the /HalftoneMode userparam can be
% concatenated to this file (see below).
% =====================================================================
% Try to get the previously defined resource
{ /StochasticDefault /Halftone findresource } stopped
{
pop pop
% Need to load the Stochastic Halftone using the lib file
(ht_ccsto.ps) runlibfile
} if
% If we didn't error out by now, then go ahead and define the /Default
/StochasticDefault /Halftone findresource
/Default exch /Halftone defineresource
sethalftone % Use the halftone
% Uncomment the next line to make the Stocahstic halftoning be "sticky"
% << /HalftoneMode 1 >> setuserparams
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