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diff --git a/doc/sample_downscale_device.htm b/doc/sample_downscale_device.htm deleted file mode 100644 index 4899f9100..000000000 --- a/doc/sample_downscale_device.htm +++ /dev/null @@ -1,235 +0,0 @@ -<!doctype html> -<html lang="en"> -<head> - <meta http-equiv="content-type" content="text/html; charset=utf-8"> - <meta name="viewport" content="user-scalable=yes, initial-scale=1, width=device-width"> - <link href="https://fonts.googleapis.com/css?family=Source+Sans+Pro:200,200i,300,300i,400,400i,600,600i,700,700i,900,900i" rel="stylesheet"> - <link rel="shortcut icon" href="images/favicon.svg"> - <title>Ghostscript: Sample CMYK 32-bit Device that Supports Post Rendering Processing</title> - <link href="default.css" rel="stylesheet" type="text/css"> -</head> - -<body> - <header><div class="title"><a href="index.html"><h1 aria-label="title">Ghostscript documentation</h1><h2 aria-label="version"></h2></a></div><a href="Search.htm" aria-label="Search" id="searchSite"><div class="search"></div></a></header> - <main> - <article> - <div class="outer"> - - <div class="inner"> -<!--START EDITING HERE--> - -<h1>Ghostscript: Sample CMYK 32-bit Device that Supports Post Rendering Processing</h1> - -<h2><a name="toc"></a>Table of contents</h2> -<ul class="toc"> - <li><a href="#Description">Description</a> - <li><a href="#Features">Features</a> - <li><a href="#devs_mak">Changes to devices/devs.mak</a> - <li><a href="#Building">Building Ghostscript with the driver</a> - <li><a href="#Source">Source code</a> -</ul> - -<!-- [1.2 end table of contents] =========================================== --> - -<!-- [1.3 begin hint] ====================================================== --> - -<p>For other information, see the <a href="Drivers.htm">Ghostscript -device drivers</a> and the documentation on <a href="Make.htm">how to build -Ghostscript</a>. - -<!-- [1.3 end hint] ======================================================== --> - -<hr> - -<!-- [1.0 end visible header] ============================================== --> - -<!-- [2.0 begin contents] ================================================== --> - -<h2><a name="Description"></a>Description</h2> - -<p> -This device is a basic CMYK 32-bit (8-bits per component) device that uses the <code>downscaler</code> -features to provide post-rendering operations on the raster data produced by Ghostscript. -<p> -It is designed to allow a developer to add code to handle the resulting raster data -and perform any desired formatting and transmission to some destination, for example -DMA to a printer or sending over a network link. -<p> -<hr> - -<h2><a name="Features"></a>Features</h2> - -<p> -The <code>downscaler</code> modules provide for the following optional post-rendering -manipulation: - -<blockquote><dl> -<dt><code>-dDownScaleFactor=<em>factor</em></code> (small non-negative integer; default = 1) -<dd>If this option set then the page is downscaled by the given factor on both -axes. For example rendering with <tt>-r600</tt> and then specifying <tt>-dDownScaleFactor=3</tt> will produce -a 200dpi image. -<p> -2 additional "special" ratios are available, 32 and 34. 32 provides a 3:2 downscale -(so from 300 to 200 dpi, if the resolution is 300 dpi as with <code>-r300</code>). 34 produces a 3:4 upscale (so from 300 to 400 dpi, similarly). -</dl></blockquote> - -<blockquote><dl> -<dt><code>-sPostRenderProfile=<em>path</em></code> (path to an ICC profile) -<dd>If this option set then the page will be color transformed using that -profile <b>after</b> downscaling. -<p> -This is useful when the file uses overprint to separately paint to some -subset of the C, M, Y, and K colorants, but the final CMYK is to be color -corrected for printing or display. -</dl></blockquote> - -<p>The <code>ds32</code> device can perform rudimentary automatic bitmap -'trapping' on the final rendered bitmap. This code is disabled by default; see -the <a href="#trapping_patent_note">note</a> below as to why. - -<p>Trapping is a process whereby the output is adjusted to minimise the -visual impact of offsets between each printed plane. Typically this involves -slightly extending abutting regions that are rendered in different inks. The -intent of this is to avoid the unsightly gaps that might be otherwise be -revealed in the final printout if the different color plates do not exactly -line up. - -<p>This trapping is controlled by 3 device parameters. Firstly the maximum -X and Y offsets are specified using: -<blockquote><dl> -<dt><code>-dTrapX=N</code> -<dd>and -<dt> <code>-dTrapY=N</code> -<dd>(where <code>N</code> is a figure in pixels, <b>before</b> the downscaler is applied). -</dl></blockquote> - -<p>The final control is to inform the trapping process in what order inks -should be processed, from darkest to lightest. For a typical CMYK device -this order would be [ 3 1 0 2 ] (K darker than M darker than C darker than Y). -This is the default. - -<p>To override these defaults, the <code>TrapOrder</code> parameter can be used. Since -this parameter requires an array, it must be specified using a different method. For -example, if Cyan is darker than Magenta: - -<blockquote><code> - gs -sDEVICE=ds32 -dTrapX=2 -dTrapY=2 -c "<< /TrapOrder [ 3 0 1 2 ] >> setpagedevice" -f examples\colorcir.ps -</code></blockquote> - -<h4><a name="trapping_patent_note"></a>Trapping patents</h4> - -<p>Trapping is an technology area encumbered by many patents. Until -we can convince ourselves that our trapping code is not covered by -any of these patents, the functionality is disabled by default.</p> - -<p>It can be enabled by building with the <tt>ENABLE_TRAPPING</tt> -define, but before you do so you should convince yourself that -either:</p> - -<ul> -<li>The trapping code is not covered by any existing patent. -<li>Any patents that do cover the code are invalid in your -jurisdiction. -<li>That you have appropriate patent licenses for any patents - that do apply. -</ul> - -<p>You bear full responsibility for choosing to build with -<tt>ENABLE_TRAPPING</tt>. - -<p> - -<p> -<hr> - -<h2><a name="devs_mak"></a>Changes to devices/devs.mak</h2> - -<p> -The make files used to build Ghostscript use the file devices/devs.mak to -describe what is needed for devices that can be built into the executable, -such as source code files, header files, libraries and dependencies on -other parts of Ghostscript. -<p> -The section below can be added to the end of the devices/devs.mak file: - -<blockquote> -<pre> -### -------- Example 32-bit CMYK downscaled device --------------------- ### -# NB: downscale_ is standard in the lib (LIB1s) -$(DD)ds32.dev : $(DEVOBJ)gdevds32.$(OBJ) $(GLD)page.dev \ - $(GDEV) $(DEVS_MAK) $(MAKEDIRS) - $(SETPDEV2) $(DD)ds32 $(DEVOBJ)gdevds32.$(OBJ) - $(ADDMOD) $(DD)ds32 -include $(GLD)page - -$(DEVOBJ)gdevds32.$(OBJ) : $(DEVSRC)gdevds32.c $(gsicc_cache_h) $(gxdownscale_h) $(AK) \ - $(arch_h) $(gdevprn_h) $(stdio__h) $(stdint__h) $(DEVS_MAK) $(MAKEDIRS) - $(DEVCC) $(DEVO_)gdevds32.$(OBJ) $(C_) $(DEVSRC)gdevds32.c -</blockquote> - -This snippet is also in a commented block at the top of the source code file. -<p> -<hr> - -<h2><a name="Building"></a>Building Ghostscript with the driver</h2> - -<p> -The make system also needs to be told to include the <code>ds32</code> device. This can -either be added to the top level make file on one of the <code>DEVICE_DEVS</code> lines, -for example, in <code>psi/msvc.mak</code> for the Windows build: -<blockquote> -<pre> -DEVICE_DEVS21=$(DD)ds32.dev $(DD)spotcmyk.dev $(DD)devicen.dev $(DD)bmpsep1.dev $(DD)bmpsep8.dev $(DD)bmp16m.dev $(DD)bmp32b.dev $(DD)psdcmyk.dev $(DD)psdrgb.dev $(DD)cp50.dev $(DD)gprf.dev -</blockquote> - -Rather than editing a make file, there is a convenient macro that allows the extra device -to be added to the build command line, <code>DEVICE_DEVS_EXTRA</code>. For example, on -linux: -<blockquote> -<pre> -make DEVICE_DEVS_EXTRA=obj/ds32.dev -</blockquote> -or, on Windows: -<blockquote> -<pre> -nmake -f psi/msvc32.mak DEVICE_DEVS_EXTRA=obj\ds32.dev -</blockquote> -<hr> - -<h2><a name="Source"></a>Source code</h2> - -<p> -The source for this device driver is in: <a href="gdevds32.c">doc/gdevds32.c</a> - -<p> -<hr> - -<!-- [2.0 end contents] ==================================================== --> - -<!-- [3.0 begin visible trailer] =========================================== --> - -<p> - <small>Copyright © 2016-2022 Artifex Software, Inc. All rights reserved.</small> - -<p> -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 that -license. Refer to licensing information at <a href="https://www.artifex.com">https://www.artifex.com</a> -or contact Artifex Software, Inc., 1305 Grant Avenue - Suite 200, -Novato, CA 94945, U.S.A., +1(415)492-9861, for further information. - -<p> -<small>Ghostscript version 10.00.0, 7 September 2022 - -<!-- [3.0 end visible trailer] ============================================= --> - -<!--FINISH EDITING HERE--> - </div><!-- close inner --> - </div><!-- close outer --> - </article> - </main> - <script src="site.js"></script> -</body> -</html> |