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diff --git a/doc/VectorDevices.htm b/doc/VectorDevices.htm deleted file mode 100644 index b567fa748..000000000 --- a/doc/VectorDevices.htm +++ /dev/null @@ -1,1531 +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>High Level Output Devices</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>High Level Output Devices</h1> - -<h2><a name="toc"></a>Table of contents</h2> -<ul class="toc"> - <li><a href="#Overview">Overview</a></li> - <li><a href="#PXL">PCL-XL file output</a></li> - <li><a href="#TXT">Text output</a></li> - <li><a href="#DOCX">DOCX file output</a></li> - <li><a href="#XPS">XPS file output</a></li> - <li><a href="#PDFWRITE">PDF file output</a></li> - <li> - <ul> - <li><a href="#COMMON">Common controls and features</a> - <li><a href="#PSPDF_IN">Controls and features specific to PostScript and PDF input</a> - <li><a href="#PXL_IN">Controls and features specific to PCL and PXL input</a> - <li><a href="#PDF">PDF file output</a> - <li><a href="#PS">PostScript file output</a> - <li><a href="#EPS">EPS file output</a> - </ul> - </li> - <li><a href="#PDFX">PDF/X-3 file output</a></li> - <li><a href="#PDFA">PDF/A file output</a></li> - <li><a href="#PPD">Ghostscript PDF printer description</a></li> - <li><a href="#Extensions">pdfmark extensions</a></li> - <li><a href="#Limitations">Limitations</a></li> -</ul> - -<!-- [1.2 end table of contents] =========================================== --> - -<!-- [1.3 begin hint] ====================================================== --> - -<p>For other information, see the <a href="Readme.htm">Ghostscript overview</a>. - -<!-- [1.3 end hint] ======================================================== --> - -<hr> - -<!-- [1.0 end visible header] ============================================== --> - -<!-- [2.0 begin contents] ================================================== --> - -<h2><a name="Overview"></a>Overview</h2> - -<p> -High level devices are Ghostscript output devices which do not render to a raster, -in general they produce 'vector' as opposed to bitmap output. Such devices currently -include: pdfwrite, ps2write, eps2write, txtwrite, xpswrite, pxlmono, pxlcolor and -docxwrite. -</p> - -<p> -Although these devices produce output which is not a raster, they still work in the -same general fashion as all Ghostscript devices. The input (PostScript, PDF, XPS, PCL -or PXL) is handled by an appropriate interpreter, the interpreter processes the input -and produces from it a sequence of drawing 'primitives' which are handed to the device. -The device decides whether to handle the primitive itself, or call upon the graphics -library to render the primitive to the final raster. -</p> - -<p> -Primitives are quite low level graphics operations; as an example consider the PDF -sequence '0 0 100 100 re f'. This constructs a rectangle with the bottom left -corner at 0,0 which is 100 units wide by 100 units high, and fills it with the current -color. A lower level implementation using only primitives would first move the current -point to 0,0, then construct a line to 0,100, then a line to 100,100, a line to 100, 0 -and finally a line back to 0,0. It would then fill the result. -</p> - -<p> -Obviously that's a simple example but it serves to demonstrate the point. -</p> - -<p> -Now the raster devices all call the graphics library to process primitives (though they -may choose to take some action first) and render the result to a bitmap. The high level -devices instead reassemble the primitives back into high level page description and -write the result to a file. This means that the output, while it should be visually the -same as the input (because it makes the same marks), is <b>not</b> the same as the -original input, even if the output Page Description Language is the same as the input -one was (eg PDF to PDF). -</p> - -<p> -Why is this important ? Firstly because the description of the page won't be the same, -if your workflow relies upon (for example) finding rectangles in the description then -it might not work after it has been processed by a high level device, as the -rectangles may all have turned into lengthy path descriptions. -</p> -<p>In addition, any part of the original input which does not actually make marks on the -page (such as hyperlinks, bookmarks, comments etc) will normally <b>not</b> be -present in the output, even if the output is the same format. In general the PDF -interpreter and the PDF output device (pdfwrite) try to preserve the non-marking -information from the input, but some kinds of content are not carried across, in -particular comments are not preserved. -</p> - -<p> -We often hear from users that they are 'splitting' PDF files, or 'modifying' them, or converting -them to PDF/A, and it's important to realize that this is not what's happening. Instead, -a new PDF file is being created, which should <b>look</b> the same as the original, but -the actual insides of the PDF file are not the same as the original. This may not be a -problem, but if it's important to keep the original contents, then you need to use -a different tool (we'd suggest MuPDF, also available from Artifex). Of course, if the -<b>intention</b> is to produce a modified PDF file (for example, reducing the resolution -of images, or changing the colour space), then clearly you cannot keep the original -contents unchanged, and pdfwrite performs these tasks well. -</p> - - -<hr> -<h2><a name="PXL"></a>PCL-XL (PXL)</h2> - -<p>The <tt>pxlmono</tt> and <tt>pxlcolor</tt> devices output HP PCL-XL, -a graphic language understood by many recent laser printers. - -<h3>Options</h3> -<blockquote> -<dl> -<dt><code>-dCompressMode=<em>1 | 2 | 3</em></code> (default is 1) -<dd>Set the compression algorithm used for bitmap graphics. RLE=1, JPEG=2, DeltaRow=3. -When JPEG=2 is on, it is applied only to full-color images; indexed-color graphics -and masks continues to be compressed with RLE. -</dl></blockquote> - -<hr> -<h2><a name="TXT"></a>Text output</h2> - -<p> The txtwrite device will output the text contained in the original -document as Unicode. - -<h3>Options</h3> -<blockquote> -<dl> -<dt><code>-dTextFormat=<em>0 | 1 | 2 | 3 | 4 </em></code> (default is 3)</dt> - <dd>Format 0 is intended for use by developers and outputs XML-escaped Unicode -along with information regarding the format of the text (position, font name, -point size, etc). The XML output is the same format as the MuPDF output, but -no additional processing is performed on the content, so no block detection.<p></dd> -<dd>Format 1 uses the same XML output format, but attempts similar processing to -MuPDF, and will output blocks of text. Note the algorithm used is not the same -as the MuPDF code, and so the results will not be identical.<p></dd> -<dd>Format 2 outputs Unicode (UCS2) text (with a Byte Order Mark) which -approximates the layout of the text in the original document.<p></dd> -<dd>Format 3 is the same as format 2, but the text is encoded in UTF-8.<p></dd> -<dd>Format 4 is internal format similar to Format 0 but with extra information.<p></dd> -</dl></blockquote> - -<p> - -<hr> -<h2><a name="DOCX"></a>DOCX output</h2> - -<p>The docxwrite device creates a DOCX file suitable for use with applications -such as Word or LibreOffice, containing the text in the original document. -</p> -<p>Rotated text is placed into textboxes. Heuristics are used to group -glyphs into words, lines and paragraphs; for some types of formatting, these -heuristics may not be able to recover all of the original document structure. -</p> -<p>This device currently has no special configuration parameters.</p> - -<p> - -<hr> -<h2><a name="XPS"></a>XPS file output</h2> - -<p>The xpswrite device writes its output according to the Microsoft XML Paper Specification. This -specification was later amended to the Open XML Paper specification, submitted to ECMA International -and adopted as ECMA-388. -</p> -<p>This device currently has no special configuration parameters.</p> -</p> -<p> - -<hr> -<h2><a name="PDFWRITE"></a>The family of PDF and PostScript output devices</h2> - -<blockquote><ul> -<li><a href="#COMMON">Common controls and features</a> -<li><a href="#PSPDF_IN">Controls and features specific to PostScript and PDF input</a> -<li><a href="#PXL_IN">Controls and features specific to PCL and PXL input</a> -<li><a href="#PDF">PDF file output</a> -<li><a href="#PS">PostScript file output</a> -<li><a href="#EPS">EPS file output</a> -</ul></blockquote> - -<h3><a name="COMMON"></a>Common controls and features</h3> -<p> -The PDF and PostScript (including Encapsulated PostScript, or EPS) devices have much of their code -in common, and so many of the controlling parameters are also common amongst the devices. -The pdfwrite, ps2write and eps2write devices create PDF or PostScript files whose visual appearance should match, as closely -as possible, the appearance of the original input (PS, PDF, XPS, PCL, PXL). There are a number of caveats -as mentioned in the <a href="#Overview">overview</a> above. In addition to the general comments there are some additional points that -bear mentioning; -</p> -<p> -PCL has a graphics model which differs significantly from the PostScript or PDF one, in particular it has -a form of transparency called RasterOps, some aspects of which cannot be represented in PDF at a high -level (or at all, in PostScript). The pdfwrite device makes no attempt to handle this, and the resulting PDF file will <b>not</b> match -the original input. The only way to deal with these types of file is to render the whole page to a bitmap -and then 'wrap' the bitmap as a PDF file. Currently we do not do this either, but it is possible that a -future enhancement may do so. -</p> -<p> -If the input contains PDF-compatible transparency, but the ps2write device is selected, or the pdfwrite device -is selected, but has been told to limit the PDF feature set to a version less than 1.4, the transparency -cannot be preserved. In this case the entire page is rendered to a bitmap and that bitmap is 'wrapped up' -in appropriate PDF or PostScript content. The output should be visually the same as the input, but since -it has been rendered it will not scale up or down well, unlike the original, vector, content of the input. -</p> - -<p> -The <em>options</em> in the command line may include any switches that may -be used with the language interpreter appropriate for the input (see <a -href="Use.htm#Options">here</a> for a complete list). In addition the -following options are common to all the pdfwrite family of devices, and should -work when specified on the command line with any of the language interpreters. - -<dl> - -<dt><code>-r</code><em>resolution</em> -<dd>Sets the resolution for pattern fills, for fonts that must be -converted to bitmaps and any other rendering required (eg rendering -transparent pages for output to PDF versions < 14). The default internal -resolution for pdfwrite is 720dpi. - -<dt><code>-dUNROLLFORMS</code><dd>When converting from PostScript, -pdfwrite (and ps2write) preserve the use of Form resources as Form -XObjects in the output. Some badly written PostScript can cause this -to produce incorrect output (the Quality Logic CET tests for example). -By setting this flag, forms will be unrolled and stored in the output -each time they are used, which avoids the problems. Note that the output -file will of course be larger this way. -We do not attempt to preserve Form XObjects from PDF files, unless they -are associated with transparency groups. - -<dt><code>-dNoOutputFonts</code></dt><dd>Ordinarily the pdfwrite device family -goes to considerable lengths to preserve fonts from the input as fonts -in the output. However in some highly specific cases it can be useful to -have the text emitted as linework/bitmaps instead. Setting this switch -will prevent these devices from emitting any fonts, all text -will be stored as vectors (or bitmaps in the case of bitmapped fonts) -in the page content stream. Note that this will produce larger output -which will process more slowly, render differently and particularly -at lower resolution produce less consistent text rendering. Use with -caution. - -<dt><code>-dCompressFonts=</code><em>boolean</em> -<dd>Defines whether <code>pdfwrite</code> will compress embedded fonts in -the output. The default value is <code>true</code>; the -<code>false</code> setting is intended only for debugging as it will result in larger output. - -<dt><code>-dCompressStreams=</code><em>boolean</em> -<dd>Defines whether <code>pdfwrite</code> will compress streams other than those in fonts or pages in -the output. The default value is <code>true</code>; the -<code>false</code> setting is intended only for debugging as it will result in larger output. - -</dl> -<h4><a name="distillerparams"></a>Distiller Parameters</h4> -<p> -<em>Options</em> may also include -<code>-d</code><em>parameter</em>=<em>value</em> or -<code>-s</code><em>parameter</em>=<em>string</em> switches for setting -"distiller parameters", Adobe's documented parameters for controlling the -conversion of PostScript into PDF. The PostScript <code>setdistillerparams</code> and -<code>currentdistillerparams</code> operators are also recognized when -the input is PostScript, and provide an equivalent way to set these -parameters from within a PostScript input file. -</p> -<p>Although the name implies that these parameters are for controlling PDF output, in -fact the whole family of devices use these same parameters to control the conversion into -PostScript and EPS as well. -</p> - -<p> -The pdfwrite family of devices recognize all of the Acrobat Distiller 5 parameters -defined in the DistillerParameters (version 5) document available from the Adobe web site. -Cells in the table below containing '=' mean that the value of the parameter is the same as in the -"default" column. - -<blockquote> -<table> -<tr> -<th align="left" style="width:31%">Parameter name</th> - -<th align="left" style="width:11.5%">Notes</th> - -<th align="left" style="width:11.5%">default</th> - -<th align="left" style="width:11.5%">screen</th> - -<th align="left" style="width:11.5%">ebook</th> - -<th align="left" style="width:11.5%">printer</th> - -<th align="left" style="width:11.5%">prepress</th> -</tr> -<tr valign=top><td><code>AlwaysEmbed</code></td><td><a href="#note_13">(13)</a></td><td>[ ]</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>AntiAliasColorImages</code></td><td><a href="#note_0">(0)</a></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>AntiAliasGrayImages</code></td><td><a href="#note_0">(0)</a></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>AntiAliasMonoImages</code></td><td><a href="#note_0">(0)</a></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>ASCII85EncodePages</code></td><td></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>AutoFilterColorImages</code></td><td><a href="#note_1">(1)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>AutoFilterGrayImages</code></td><td><a href="#note_1">(1)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>AutoPositionEPSFiles</code></td><td><a href="#note_0">(0)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>AutoRotatePages</code></td><td></td><td>/PageByPage</td><td>/PageByPage</td><td>/All</td><td>/None</td><td>/None</td></tr> -<tr valign=top><td><code>Binding</code></td><td><a href="#note_0">(0)</a></td><td>/Left</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>CalCMYKProfile</code></td><td><a href="#note_0">(0)</a></td><td>()</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>CalGrayProfile</code></td><td><a href="#note_0">(0)</a></td><td>()</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>CalRGBProfile</code></td><td><a href="#note_0">(0)</a></td><td>()</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>CannotEmbedFontPolicy</code></td><td><a href="#note_0">(0)</a></td><td>/Warning</td><td>/Warning</td><td>/Warning</td><td>/Warning</td><td>/Error</td></tr> -<tr valign=top><td><code>ColorACSImageDict</code></td><td><a href="#note_13">(13)</a></td><td><a href="#note_7">(note 7)</a></td><td><a href="#note_10">(note 10)</a></td><td><a href="#note_10">(note 10)</a></td><td><a href="#note_8">(note 8)</a></td><td><a href="#note_9">(note 9)</a></td></tr> -<tr valign=top><td><code>ColorConversionStrategy</code></td><td><a href="#note_6">(6)</a></td><td>LeaveColorUnchanged</td><td>RGB</td><td>RGB</td><td>UseDeviceIndependentColor</td><td>LeaveColorUnchanged</td></tr> -<tr valign=top><td><code>ColorImageDepth</code></td><td></td><td>-1</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>ColorImageDict</code></td><td><a href="#note_13">(13)</a></td><td><a href="#note_7">(note 7)</a></td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>ColorImageFilter</code></td><td></td><td>/DCTEncode</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>ColorImageDownsampleThreshold</code></td><td></td><td>1.5</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>ColorImageDownsampleType</code></td><td><a href="#note_3">(3)</a></td><td>/Subsample</td><td>/Average</td><td>/Average</td><td>/Average</td><td>/Bicubic</td></tr> -<tr valign=top><td><code>ColorImageResolution</code></td><td></td><td>72</td><td>72</td><td>150</td><td>300</td><td>300</td></tr> -<tr valign=top><td><code>CompatibilityLevel</code></td><td></td><td>1.7</td><td>1.5</td><td>1.5</td><td>1.7</td><td>1.7</td></tr> -<tr valign=top><td><code>CompressPages</code></td><td><a href="#note_14">(14)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>ConvertCMYKImagesToRGB</code></td><td></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>ConvertImagesToIndexed</code></td><td><a href="#note_0">(0)</a></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>CoreDistVersion</code></td><td></td><td>4000</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>CreateJobTicket</code></td><td><a href="#note_0">(0)</a></td><td>false</td><td>false</td><td>false</td><td>true</td><td>true</td></tr> -<tr valign=top><td><code>DefaultRenderingIntent</code></td><td></td><td>/Default</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>DetectBlends</code></td><td><a href="#note_0">(0)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>DoThumbnails</code></td><td><a href="#note_0">(0)</a></td><td>false</td><td>false</td><td>false</td><td>false</td><td>true</td></tr> -<tr valign=top><td><code>DownsampleColorImages</code></td><td></td><td>false</td><td>true</td><td>true</td><td>false</td><td>false</td></tr> -<tr valign=top><td><code>DownsampleGrayImages</code></td><td></td><td>false</td><td>true</td><td>true</td><td>false</td><td>false</td></tr> -<tr valign=top><td><code>DownsampleMonoImages</code></td><td></td><td>false</td><td>true</td><td>true</td><td>false</td><td>false</td></tr> -<tr valign=top><td><code>EmbedAllFonts</code></td><td></td><td>true</td><td>false</td><td>true</td><td>true</td><td>true</td></tr> -<tr valign=top><td><code>EmitDSCWarnings</code></td><td><a href="#note_0">(0)</a></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>EncodeColorImages</code></td><td></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>EncodeGrayImages</code></td><td></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>EncodeMonoImages</code></td><td></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>EndPage</code></td><td><a href="#note_0">(0)</a></td><td>-1</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>GrayACSImageDict</code></td><td><a href="#note_13">(13)</a></td><td><a href="#note_7">(note 7)</a></td><td><a href="#note_7">(note 7)</a></td><td><a href="#note_10">(note 10)</a></td><td><a href="#note_8">(note 8)</a></td><td><a href="#note_9">(note 9)</a></td></tr> -<tr valign=top><td><code>GrayImageDepth</code></td><td></td><td>-1</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>GrayImageDict</code></td><td><a href="#note_13">(13)</a></td><td><a href="#note_7">(note 7)</a></td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>GrayImageDownsampleThreshold</code></td><td></td><td>1.5</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>GrayImageDownsampleType</code></td><td><a href="#note_3">(3)</a></td><td>/Subsample</td><td>/Average</td><td>/Bicubic</td><td>/Bicubic</td><td>/Bicubic</td></tr> -<tr valign=top><td><code>GrayImageFilter</code></td><td></td><td>/DCTEncode</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>GrayImageResolution</code></td><td></td><td>72</td><td>72</td><td>150</td><td>300</td><td>300</td></tr> -<tr valign=top><td><code>ImageMemory</code></td><td><a href="#note_0">(0)</a></td><td>524288</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>LockDistillerParams</code></td><td></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>LZWEncodePages</code></td><td><a href="#note_2">(2)</a></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>MaxSubsetPct</code></td><td></td><td>100</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>MonoImageDepth</code></td><td></td><td>-1</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>MonoImageDict</code></td><td><a href="#note_13">(13)</a></td><td><<K -1>></td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>MonoImageDownsampleThreshold</code></td><td></td><td>1.5</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>MonoImageDownsampleType</code></td><td></td><td>/Subsample</td><td>/Subsample</td><td>/Subsample</td><td>/Subsample</td><td>/Subsample</td></tr> -<tr valign=top><td><code>MonoImageFilter</code></td><td></td><td>/CCITTFaxEncode</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>MonoImageResolution</code></td><td></td><td>300</td><td>300</td><td>300</td><td>1200</td><td>1200</td></tr> -<tr valign=top><td><code>NeverEmbed</code></td><td><a href="#note_13">(13)</a></td><td><a href="#note_11">(note 11)</a><a href="#note_12">(note 12)</a></td><td><a href="#note_11">(note 11)</a><a href="#note_12">(note 12)</a></td><td><a href="#note_11">(note 11)</a><a href="#note_12">(note 12)</a></td><td>[ ]<a href="#note_12">(note 12)</a></td><td>[ ]<a href="#note_12">(note 12)</a></td></tr> -<tr valign=top><td><code>OffOptimizations</code></td><td></td><td>0</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>OPM</code></td><td></td><td>1</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>Optimize</code></td><td><a href="#note_0">(0</a>,<a href="#note_5">5)</a></td><td>false</td><td>true</td><td>true</td><td>true</td><td>true</td></tr> -<tr valign=top><td><code>ParseDSCComments</code></td><td></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>ParseDSCCommentsForDocInfo</code></td><td></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>PreserveCopyPage</code></td><td><a href="#note_0">(0)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>PreserveEPSInfo</code></td><td><a href="#note_0">(0)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>PreserveHalftoneInfo</code></td><td></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>PreserveOPIComments</code></td><td><a href="#note_0">(0)</a></td><td>false</td><td>false</td><td>false</td><td>true</td><td>true</td></tr> -<tr valign=top><td><code>PreserveOverprintSettings</code></td><td></td><td>false</td><td>false</td><td>false</td><td>true</td><td>true</td></tr> -<tr valign=top><td><code>sRGBProfile</code></td><td><a href="#note_0">(0)</a></td><td>()</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>StartPage</code></td><td><a href="#note_0">(0)</a></td><td>1</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>SubsetFonts</code></td><td></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>TransferFunctionInfo</code></td><td><a href="#note_4">(4)</a></td><td>/Preserve</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>UCRandBGInfo</code></td><td></td><td>/Remove</td><td>/Remove</td><td>/Remove</td><td>/Preserve</td><td>/Preserve</td></tr> -<tr valign=top><td><code>UseFlateCompression</code></td><td><a href="#note_2">(2)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>UsePrologue</code></td><td><a href="#note_0">(0)</a></td><td>false</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>PassThroughJPEGImages</code></td><td><a href="#note_15">(15)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -<tr valign=top><td><code>PassThroughJPXImages</code></td><td><a href="#note_16">(16)</a></td><td>true</td><td>=</td><td>=</td><td>=</td><td>=</td></tr> -</table></blockquote> - -<p> -<a name="note_0">(note 0)</a> -This parameter can be set and queried, but currently has no effect. - -<p> -<a name="note_1">(note 1)</a> -<code>-dAutoFilterxxxImages=false</code> works since Ghostscript version 7.30. -Older versions of Ghostscript don't examine the image to -decide between JPEG and LZW or Flate compression: they always use -Flate compression. - -<p> -<a name="note_2">(note 2)</a> -Because the LZW compression scheme was covered by patents at the time this -device was created, <code>pdfwrite</code> does not actually use LZW compression: -all requests for LZW compression are ignored. -<tt>UseFlateCompression</tt> is treated as always on, but the switch <code>CompressPages</code> -can be set to false to turn off page level stream compression. -Now that the patent has expired, we could change this should it become worthwhile. - -<p> -<a name="note_3">(note 3)</a> -The <code>xxxDownsampleType</code> parameters can also have the value -/Bicubic (a Distiller 4 feature), this will use a Mitchell filter. (older -versions of pdfwrite simply used Average instead). Note; if a non-integer -downsample factor is used the code will clamp to the nearest integer (if -the difference is less than 0.1) or will silently switch to the old bicubic -filter, NOT the Mitchell filter. - -<p> -<a name="note_4">(note 4)</a> -The default for transfer functions is to preserve them, this is because transfer functions are -a device-dependent feature, a set of transfer functions designed for an RGB device will give -incorrect output on a CMYK device for instance. The pdfwrite device does now support /Preserve, -/Apply and /Remove (the previous documentation was incorrect, application of transfer functions -was not supported). PDF 2.0 deprecates the use of transfer functions, and so when producing PDF 2.0 -compatible output if the TransferFunctionInfor is set to /Preserve it will be silently replaced with /Apply. -You can instead specifically set TransferFunctionInfo to /Remove when producing PDF 2.0 in order to -avoid the transfer function being applied. - -<p> - -<a name="note_5">(note 5)</a> -Use the -dFastWebView command line switch to 'optimize' output. -<p> - -<a name="note_6">(note 6)</a> - -The value <code>UseDeviceIndependentColorForImages</code> works the same as -<code>UseDeviceIndependentColor</code>. -The value <code>sRGB</code> actually converts to RGB with the default Ghostscript conversion. -The new Ghostscript-specific value <code>Gray</code> converts all colors to DeviceGray. -With the introduction of new color conversion code in version 9.11 it is no longer necessary to -set <code>ProcessColorModel</code> when selecting <code>Gray</code>, <code>RGB</code> or <code>CMYK</code>. It is also no -longer necessary to set <code>UseCIEColor</code> for <code>UseDeviceIndependentColor</code> to -work properly, and the use of <code>UseCIEColor</code> is now strongly discouraged. -<p> -<a name="note_7">(note 7)</a> - The default image parameter dictionary is -<blockquote><code> -<< /QFactor 0.9 /Blend 1 /HSamples [2 1 1 2] /VSamples [2 1 1 2] >> -</code></blockquote> - -<p> -<a name="note_8">(note 8)</a> -The printer ACS image parameter dictionary is -<blockquote><code> -<< /QFactor 0.4 /Blend 1 /ColorTransform 1 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> -</code></blockquote> - -<p> -<a name="note_9">(note 9)</a> -The prepress ACS image parameter dictionary is -<blockquote><code> -<< /QFactor 0.15 /Blend 1 /ColorTransform 1 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> -</code></blockquote> - -<p> -<a name="note_10">(note 10)</a> -The screen and ebook ACS image parameter dictionary is -<blockquote><code> -<< /QFactor 0.76 /Blend 1 /ColorTransform 1 /HSamples [2 1 1 2] /VSamples [2 1 1 2] >> -</code></blockquote> - -<p> -<a name="note_11">(note 11)</a> -The default, screen, and ebook settings never embed the 14 standard fonts -(Courier, Helvetica, and Times families, Symbol, and ZapfDingbats). -This behaviour is intentional but can be overridden by: -<blockquote><code> -<< /NeverEmbed [ ] >> setdistillerparams -</code></blockquote> - -<p> -<a name="note_12">(note 12)</a> -<code>NeverEmbed</code> can include CID font names. -If a CID font is substituted in <code>lib/cidfmap</code>, -the substitute font name is used when the CID font is embedded, -and the original CID font name is used when it is not embedded. -<code>NeverEmbed</code> should always specify the original CID font -name. - -<p> -<a name="note_13">(note 13)</A> -The arrays <code>AlwaysEmbed</code> and <code>NeverEmbed</code> and -image parameter dictionaries <code>ColorACSImageDict</code>, -<code>ColorACSImageDict</code>, <code>ColorImageDict</code>, - -<code>GrayACSImageDict</code>, <code>GrayImageDict</code>, -<code>MonoImageDict</code> cannot be specified on the command line. -To specify these, you must use PostScript, either by including it in the PostScript source -or by passing the <code>-c</code> command-line parameter to ghostscript as described in <a href="#Limitations">Limitations</A> below. -For example, including the PostScript string in your file <tt>in.ps</tt>: -<blockquote><tt><</AlwaysEmbed [/Helvetica /Times-Roman]>> setdistillerparams</tt></blockquote> -is equivalent to invoking: - -<blockquote><code>gs -dBATCH -dSAFER -DNOPAUSE -q -sDEVICE=pdfwrite -sOutputFile=out.pdf -c -'<</AlwaysEmbed [/Helvetica /Times-Roman]>> setdistillerparams' -f -in.ps</code></blockquote> - -or using the extra parameters in a file: - -<blockquote><code>@params.in</code></blockquote> - -where the file <b>params.in</b> contains: - -<blockquote><code>-c '<</AlwaysEmbed [/Helvetica /Times-Roman]>> setdistillerparams' -f -in.ps</code></blockquote> - -<p> -<a name="note_14">(note 14)</a> -The default value of <code>CompressPages</code> is <code>false</code> for ps2write and eps2write. - -<p> -<a name="note_15">(note 15)</a> -When <code>true</code> image data in the source which is encoded using the DCT (JPEG) filter will not be decompressed -and then recompressed on output. This prevents the multiplication of JPEG artefacts caused by lossy compression. -</code><code>PassThroughJPEGImages</code> currently only affects simple JPEG images. It has no effect on JPX (JPEG2000) encoded images (see below) -or masked images. In addition this parameter will be ignored if the pdfwrite device needs to modify the source data. This can happen if the image -is being downsampled, changing colour space or having transfer functions applied. Note that this parameter essentially overrides -the 'EncodeColorImages' and 'EncodeGrayImages' parameters if they are false, the image will still be written with a DCTDecode filter. NB this -feature currently only works with PostScript or PDF input, it does not work with PCL, PXL or XPS input. - -<p> -<a name="note_16">(note 16)</a> -When <code>true</code> image data in the source which is encoded using the JPX (JPEG 2000) filter will not be decompressed -and then recompressed on output. This prevents the multiplication of JPEG artefacts caused by lossy compression. -</code><code>PassThroughJPXImages</code> currently only affects simple JPX encoded images. It has no effect on JPEG encoded images (see above) -or masked images. In addition this parameter will be ignored if the pdfwrite device needs to modify the source data. This can happen if the image -is being downsampled, changing colour space or having transfer functions applied. Note that this parameter essentially overrides -the 'EncodeColorImages' and 'EncodeGrayImages' parameters if they are false, the image will still be written with a JPXDecode filter. NB this -feature currently only works with PostScript or PDF input, it does not work with PCL, PXL or XPS input. - -<h4><a name="Color_Conversion_and_Management"></a>Color Conversion and Management</h4> -<p> -As of the 9.11 pre-release, the color management in the pdfwrite family has been substantially -altered so that it now uses the same Color Management System as rendering (the default -is LCMS2). This considerably improves the color handling in both pdfwrite and ps2write, -particularly in the areas of Separation and DeviceN color spaces, and Indexed color -spaces with images. -</p> - -<p>Note that while pdfwrite uses the same CMS as the rendering devices, this does not mean that the entire suite of options is available, as described -in the GS9_Colour Management.pdf file. The colour management code has no effect at all unless either ColorConversionStrategy -or ConvertCMYKImagesToRGB is set, or content has to be rendered to an image (this is rare and usually required only when -converting a PDF file with transparency to a version < PDF 1.4). -</p> -<p>Options based on object type (image, text, linework) are not used, all objects are converted using the same scheme. -<code>-dKPreserve</code> has no effect because we will not convert CMYK to CMYK. <code>-dDeviceGrayToK</code> also has no effect; -when converting to CMYK DeviceGray objects are left in DeviceGray since that can be mapped directly to the K channel.</p> - -The <code>ColorConversionStrategy</code> switch can now be set to <code>LeaveColorUnchanged</code>, <code>Gray</code>, <code>RGB</code>, <code>CMYK</code> or -<code>UseDeviceIndependentColor</code>. Note that, particularly for ps2write, <code>LeaveColorUnchanged</code> may still need to convert -colors into a different space (ICCbased colors cannot be represented in PostScript for example). <code>ColorConversionStrategy</code> can be specified either as; a string -by using the <code>-s</code> switch (<code>-sColorConversionStrategy=RGB</code>) or as a name using the <code>-d</code> switch (<code>-dColorConversionStrategy=/RGB</code>). -</p> -<p>ps2write cannot currently convert into device-independent color spaces, and so <code>UseDeviceIndependentColor</code>should not be used with ps2write (oe eps2write). -</p> -<p>All other color spaces are converted appropriately. Separation and DeviceN spaces will be preserved if possible (ps2write cannot preserve DeviceN or Lab) -and if the alternate space is not appropriate a new alternate space will be created. Eg a [/Separation (MyColor) /DeviceRGB {...}] -when the <code>ColorConversionStrategy</code> is set to <code>CMYK</code> would be converted to [/Separation (MyColor) /DeviceCMYK {...}] -The new tint transform will be created by sampling the original tint transform, converting the RGB values into CMYK, and then creating -a function to linearly interpolate between those values.</p> - -The <code>PreserveSeparation</code> switch now controls whether the pdfwrite family of devices will attempt to preserve Separation spaces. If this is set to false then -all Separation colours will be converted into the current device space specified by ProcessColorModel. -</p> - -<h4><a name="Orientation"></a>Setting page orientation</h4> - -<p> -By default Ghostscript determines viewing page orientation based on the dominant -text orientation on the page. Sometimes, when the page has text in several -orientations or has no text at all, wrong orientation can be selected. - -<p> -Acrobat Distiller parameter <code>AutoRotatePages</code> controls the -automatic orientation selection algorithm. On Ghostscript, besides -input stream, Distiller parameters can be given as command line arguments. -For instance: <code>-dAutoRotatePages=/None</code> or -<code>/All</code> or <code>/PageByPage</code>. - -<p> -When there is no text on the page or automatic page rotation is set to -<code>/None</code> an orientation value from setpagedevice is used. -Valid values are: <code>0</code> (portrait), -<code>3</code> (landscape), <code>2</code> (upside down), -and <code>1</code> (seascape). The orientation can be set from the -command line as <code>-c "<</Orientation 3>> setpagedevice"</code> -using Ghostscript directly but cannot be set in <code>ps2pdf</code>. -See <a href="#Limitations">Limitations</a> below. - -<p> -Ghostscript passes the orientation values from DSC comments to the -<code>pdfwrite</code> driver, and these are compared with the -auto-rotate heuristic. If they are different then the DSC value will be used preferentially. -If the heuristic is to be preferred over the DSC comments then comment parsing -can be disabled by setting <code>-dParseDSCComments=false</code>. -<p> - -<h3><a name="PSPDF_IN"></a>Controls and features specific to PostScript and PDF input</h3> -<dl><dt><code>-dPDFSETTINGS=</code><em>configuration</em></dt> -<dd>Presets the "distiller parameters" to one of four predefined settings:</dd> -</dl> -<ul> - -<li><code>/screen</code> selects low-resolution output similar to the -Acrobat Distiller (up to version X) "Screen Optimized" setting.</li> - -<li><code>/ebook</code> selects medium-resolution output similar to the -Acrobat Distiller (up to version X) "eBook" setting.</li> - -<li><code>/printer</code> selects output similar to the Acrobat Distiller -"Print Optimized" (up to version X) setting.</li> - -<li><code>/prepress</code> selects output similar to Acrobat Distiller -"Prepress Optimized" (up to version X) setting.</li> - -<li><code>/default</code> selects output intended to be useful across a -wide variety of uses, possibly at the expense of a larger output file.</li> - -</ul> -<p> -NB Adobe has recently changed the names of the presets it uses in Adobe Acrobat Distiller, -in order to avoid confusion with earlier versions we do not plan to change the -names of the PDFSETTINGS parameters. The precise value for each control is listed -in the table <a href="#distillerparams">above</a>. -</p> - -<dl><dt></dt> -<dd>Please be aware that the <code>/prepress</code> setting does <b>not</b> indicate -the highest quality conversion. Using any of these presets will involve altering the -input, and as such may result in a PDF of poorer quality (compared to the input) than -simply using the defaults. The 'best' quality (where best means closest to the original -input) is obtained by not setting this parameter at all (or by using <code>/default</code>). -</dd> - -<dd>The PDFSETTINGS presets should only be used if you are sure you understand that the -output will be altered in a variety of ways from the input. It is usually better to -adjust the controls individually (see the table below) if you have a genuine requirement to produce, -for example, a PDF file where the images are reduced in resolution. -</dd> -</dl> - -<h3><a name="PXL_IN"></a>Controls and features specific to PCL and PXL input</h3> -<p> -Many of the controls used for <a href="#distillerparams">distiller parameters</a> can be used on the command line with the -d or -s -switches, and these will work correctly with PCL or PXL input. However, some controls (eg /NeverEmbed) do -not take simple numeric or string arguments, and these cannot be set from the command line. When -the input is PostScript or PDF we can use the -c and -f switches to send PostScript through -the interpreter to control these parameters, but clearly this is not possible when the interpreter -does not understand PostScript. In addition some features are controlled using the PostScript -<code>pdfmark</code> operator and again that clearly is not possible unless we are using a PostScript -interpreter to read the input. -</p> -<p> -To overcome this new, GhostPCL-specific, PJL parameters have been added. These parameters are defined -as <code>PDFMARK</code> and <code>SETDISTILLERPARAMS</code>. In order to reduce confusion when using -PostScript and PCL as inputs these PJL parameters take essentially the same PostScript constructs as -the corresponding PostScript operators <code>pdfmark</code> and <code>setdistillerparams</code>. However -it is important to realise that these are <b>not</b> processed by a full PostScript interpreter, and -there are syntactic rules which must be followed carefully when using these parameters. -</p> -<p> -You cannot use arbitrary PostScript operators, only boolean, number, name, string, array and dictionary -objects are supported (but see <code>PUTFILE</code> later). All tokens <b>must</b> be separated by white space, so -while this <code>[/Test(string)]</code> is perfectly valid in PostScript, you must instead write it -as <code>[ /Test (string) ]</code> for PJL parsing. All <code>PDFMARK</code> and <code>SETDISTILLERPARAMS</code> must be set as -DEFAULT, the values must be on a single line, and delimited by "". -</p> -<p> -pdfmarks sometimes require the insertion of file objects (especially for production of PDF/A files) so -we must find some way to handle these. This is done (for the pdfmark case only) by defining a special -(non-standard) pdfmark name <code>PUTFILE</code>, this simply takes the preceding string, and uses -it as a fully qualified path to a file. Any further pdfmark operations can then use the named object -holding the file to access it. -</p> -<p> -The easiest way to use these parameters is to create a 'settings' file, put all the commands in it, -and then put it on the command line immediately before the real input file. For example: -</p> -<code> -./gpcl6 -sDEVICE=pdfwrite -dPDFA=1 -dCompressPages=false -dCompressFonts=false -sOutputFile=./out.pdf ./pdfa.pjl ./input.pcl -</code></p> -<p> -Where pdfa.pjl contains the PJL commands to create a PDF/A-1b file (see example below).</p> -<p> -<h4>Example creation of a PDF/A output file</h4> -<p>For readability the line has been bisected, when used for real this must be a single line. The 'ESC' represents -a single byte, value 0x1B, an escape character in ASCII. The line must end with an ASCII newline (\n, 0x0A) and this must be the only newline following the @PJL. -The line breaks between "" below should be replaced with space characters, the double quote charcters (") are required.</p> -<code> -</p> -<pre> -ESC%-12345X -@PJL DEFAULT PDFMARK = " -[ /_objdef {icc_PDFA} /type /stream /OBJ pdfmark -[ {icc_PDFA} << /N 3 >> /PUT pdfmark -[ {icc_PDFA} (/ghostpdl/iccprofiles/default_rgb.icc) /PUTFILE pdfmark -[ /_objdef {OutputIntent_PDFA} /type /dict /OBJ pdfmark -[ {OutputIntent_PDFA} << /S /GTS_PDFA1 /Type /OutputIntent /DestOutputProfile {icc_PDFA} /OutputConditionIdentifier (sRGB) >> /PUT pdfmark -[ {Catalog} << /OutputIntents [{OutputIntent_PDFA}] >> /PUT pdfmark -[ /Author (Ken) /Creator (also Ken) /Title (PDF/A-1b) /DOCINFO pdfmark -" -</pre> -</code> -<h4>Example using DISTILLERPARAMS to set the quality of JPEG compression.</h4> -<p> -<code> -ESC%-12345X -@PJL DEFAULT SETDISTILLERPARAMS = "<< /ColorImageDict << /QFactor 0.7 /Blend 1 /HSamples [ 2 1 1 2 ] /VSamples [ 2 1 1 2 ] >> >>" -</code> -</p> - -<h3><a name="PDF"></a>PDF file output</h3> -<dl> -<dt><code>-dMaxInlineImageSize=</code><em>integer</em> -<dd>Specifies the maximum size of an inline image, in bytes. For images larger -than this size, <code>pdfwrite</code> will create an XObject instead of embedding -the image into the context stream. -The default value is <code>4000</code>. -Note that redundant inline images must be embedded each time they occur in the -document, while multiple references can be made to a single XObject image. Therefore -it may be advantageous to set a small or zero value if the source document is expected -to contain multiple identical images, reducing the size of the generated PDF.<p></dd> - -<dt><code>-dDoNumCopies</code> -<dd>When present, causes pdfwrite to use the #copies or /NumCopies entry in the page -device dictionary to duplicate each page in the output PDF file as many times as -the 'copies' value. This is intended for use by workflow applications like CUPS -and should not be used for generating general purpose PDF files. In particular any -pdfmark operations which rely on page numbers, such as Link or Outline annotations -will not work correctly with this flag.<p></dd> - -<dt><code>-dDetectDuplicateImages</code> -<dd> Takes a Boolean argument, when set to true (the default) pdfwrite will compare all new - images with all the images encountered to date (NOT small images which are stored in-line) to see if the new image - is a duplicate of an earlier one. If it is a duplicate then instead of writing a new image into the PDF file, - the PDF will reuse the reference to the earlier image. - This can considerably reduce the size of the output PDF file, but increases the - time taken to process the file. - This time grows exponentially as more images are added, and on large input files with - numerous images can be prohibitively slow. Setting this to false will improve performance at the cost of final file size.<p></dd> - -<dt><code>-dFastWebView</code> -<dd> Takes a Boolean argument, default is false. When set to true pdfwrite will -reorder the output PDF file to conform to the Adobe 'linearised' PDF specification. -The Acrobat user interface refers to this as 'Optimised for Fast Web Viewing'. -Note that this will cause the conversion to PDF to be slightly slower and will -usually result in a slightly larger PDF file.</dd> -<dd>This option is incompatible with producing an encrypted (password protected) PDF file.<p></dd> -</dt> -</dl> - -<dl> - <dt><code>-dPreserveAnnots=</code><em>boolean</em> - <dd>We now attempt to preserve most annotations from input PDF files as annotations in the output PDF file (note, not in output PostScript!) - There are a few annotation types which are not preserved, most notably Link and Widget annotations. However, should you wish to revert - to the old behaviour, or find that the new behaviour leads to problems, you can set this switch to false which will cause all annotations to be - inserted into the page content stream, instead of preserved as annotations. - <p> In addition, finer control is available by defining an array - <code>/PreserveAnnotTypes</code>. Annotation types listed in this array will - be preserved, whilst those not listed will be drawn according to the setting os ShowAnnots and ShowAnnotTypes. - By using the controls PreserveAnnots, PreserveAnnotTypes, ShowAnnots and ShowAnnotTypes it is possible to select - by annotation type whether annotations are preserved as annotations, drawn into the page, or simply dropped. - </p> - <p> To use this feature: - <code>-c "/PreserveAnnotTypes [....] def" -f <input file></code> - <br> Where the array can contain one or more of the following names: - <code>/Stamp</code>, <code>/Squiggly</code>, <code>/Underline</code>, <code>/Link</code>, <code>/Text</code>, <code>/Highlight</code>, <code>/Ink</code>, <code>/FreeText</code>, <code>/StrikeOut</code> and <code>/stamp_dict</code>.</p> - <p> For example, adding the follow to the command line: - <code>-c "/PreserveAnnotTypes [/Text /UnderLine] def" -f <input file></code> - <br> would preserve only annotations with the subtypes "Text" and "UnderLine"</p> - </dd> - </dt> -</dl> - -<dl> - <dt><code>-dPreserveMarkedContent=</code><em>boolean</em></dt> - <dd>We now attempt to preserve marked content from input PDF files through to the output PDF file (note, not in output PostScript!) - This does not include marked content relating to optional content, because currently we do not preserve optional content, it is - instead applied by the interpreter. - <p> - This control also requires the PDF interpreter to pass the marked content to the pdfwrite device, this is only done with the - new (C-based) PDF interpreter. The old (PostScript-based) interpreter does not support this feature and will not pass marked - content to the pdfwrite device. - </p> - </dd> -</dl> - -<d1> - <dt><code>-dOmitInfoDate</code><em>boolean</em></dt> - <dd>Under some conditions the CreationDate and ModDate in the /Info dictionary are optional and can be omitted. They are required - when producing PDF/X output however. This control will allow the user to omit the /CreationDate and /ModDate entries in the - Info dictionary (and the corresponding information in the XMP metadata, if present). If you try to set this control when - writing PDF/X output, the device will give a warning and ignore this control. - </dd> -</d1> -<p></p> - -<d1> - <dt><code>-dOmitID</code><em>boolean</em></dt> - <dd>Under some conditions the /ID array trailer dictionary is optional and can be omitted. It is required - when producing PDF 2.0, or encrypted PDFs however. This control will allow the user to omit the /ID entry in the - trailer dictionary. If you try to set this control when writing PDF 2.0 or encrypted PDF output, the device will give a warning and ignore this control. - </dd> -</d1> -<p></p> - -<d1> - <dt><code>-dOmitXMP</code><em>boolean</em></dt> - <dd>Under some conditions the XMP /Metadata entry in the Catalog dictionary is optional and can be omitted. It is required - when producing PDF/A output however. This control will allow the user to omit the /Metadata entry in the - Catalog dictionary. If you try to set this control when writing PDF/A output, the device will give a warning and ignore this control. - </dd> -</d1> -<p></p> - -<p> -The following options are useful for creating PDF 1.2 files: - -<dl> - - <dt><code>-dPatternImagemask=<em>boolean</em></code></dt> - <dd>With <code>CompatibilityLevel < 1.3 </code> it specifies whether - the target viewer handles <code>ImageMask</code> with a pattern color. - Some old viewers, such as Ghostscript 3.30 fail with such constructs. - Setting this option to false, one can get more compatibility, - but the mask interpolation is lost. - With <code>CompatibilityLevel ≥ 1.3 </code> this option is ignored. - Default value is <code>false</code>.<p></dd> - - <dt><code>-dMaxClipPathSize=<em>integer</em></code></dt> - <dd>Specifies the maximum number of elements in the clipping path - that the target viewer can handle. This option is used only with - <code>CompatibilityLevel < 1.3</code> and - <code>PatternImagemask=false</code>, - and only when converting a mask into a clipping path. - If the clipping path exceeds the specified size, - the masked image and the clipping path is decomposed into smaller images. - The value of the option counts straight path segments - (curved segments are not used for representing a mask). - Default value is <code>12000</code>.<p></dd> - - <dt><code>-dMaxShadingBitmapSize=<em>integer</em></code></dt> - <dd>Specifies the maximum number of bytes allowed for representing a shading as a bitmap. - If a shading exceeds this value, the resolution of the output bitmap - is reduced to fit into the specified number of bytes. - Note that the number of bytes depends on the number of color components - in <code>ProcessColorModel</code> or <code>ColorConversionStrategy</code>, assumes 8 bits per sample, - and doesn't consider image compression or downsampling. The image is rendered at the current resolution - as specified by <code>-r</code> or the default of 720 dpi. - - Default value is <code>256000</code>. - In general larger values will result in higher quality, - but the output file size may increase dramatically, particularly with shadings which cover large areas. - - Shadings should generally only be rendered to images if <code>CompatibilityLevel</code> is 1.2 or less - or if <code>ColorCoversionStrategy</code> specifies a color space different to that of the shading.<p></dd> - - <dt><code>-dHaveTrueTypes=<em>boolean</em></code></dt> - <dd>With <code>CompatibilityLevel < 1.3</code> it specifies - whether the target viewer can handle TrueType fonts. - If not, TrueType fonts are converted into raster fonts - with resolution specified in <code>HWResolution</code>. Note that large text at higher resolutions - results in very large bitmaps which are likely to defeat caching in many printers. As a result the - text is emitted as simple images rather than as a (type 3) bitmap font. The PostScript user parameter - MaxFontItem can be used to increase the maximum size of a cache entry which will increase the size/resolution - of the text which can be stored in a font. - With <code>CompatibilityLevel ≥ 1.3</code> this option is ignored. Default value is <code>true</code>. - </dd> -</dl> - -<p> -The following options are useful for creating PDF 1.3 files: -<p> - -<dl> - - <dt><code>-dHaveTransparency=<em>boolean</em></code></dt> - <dd>With <code>CompatibilityLevel ≥ 1.4</code> it specifies - whether the target viewer can handle PDF 1.4 transparency objects. - If not, the page is converted into a single plain image with all - transparency flattened. - Default value is <code>true</code>.</dd> - -</dl> - -<h4>The following option specifies creation of a PDF/X-3 file</h4> - -<dl> -<dt><code>-dPDFX=</code><em>boolean</em> -<dd>Specifies the generated document is to follow the PDF/X-3 standard. -When true, a <code>DefaultRGB</code> <code>ColorSpace</code> resource -must be defined, and options <code>NOSUBSTDEVICECOLORS</code>, -<code>NOCIE</code> must not be specified. -Default value is <code>false</code>. -<p>The pdfwrite device does not currently support PDF/X versions other than 3.</p> -</dl> - -<p> - -When generating a PDF/X-3 document, Ghostscript performs the following -special actions to satisfy the PDF/X-3 standard: -<ul> - <li> All fonts are embedded.</li> - <li> <code>DeviceRGB</code> color space is substituted with - <code>the DefaultRGB</code> color space, - which must be defined in the <code>ColorSpace</code> category. - The easiest way is to provide it in the <code>DefaultRGB</code> file in the resource directory.</li> - <li> <code>DeviceRGB</code> color values are passed unchanged. - If a user needs a non trivial color adjustment, a non trivial - <code>DefaultRGB</code> color space must be defined.</li> - <li> Transfer functions and halftone phases are skipped.</li> - <li> <code>/PS pdfmark</code> interprets the <code>DataSource</code> - stream or file.</li> - <li><code>TrimBox</code> and <code>BleedBox</code> entries - are generated in page descriptions. - Their values can be changed using the - <code>PDFXTrimBoxToMediaBoxOffset</code>, - <code>PDFXSetBleedBoxToMediaBox</code>, and - <code>PDFXBleedBoxToTrimBoxOffset</code> - distiller parameters (see below).</li> -</ul> - - -<h4><a name="Encryption"></a> -The following switches are used for creating encrypted documents : -</h4> - -<dl> -<dt><code>-sOwnerPassword=</code><em>string</em></dt> -<dd>Defines that the document be encrypted with the specified -owner password.</dd> -</dl> - -<dl> -<dt><code>-sUserPassword=</code><em>string</em></dt> -<dd>Defines the user password for opening the document. -If empty, the document can be opened with no password, -but the owner password is required to edit it.</dd> -</dl> - -<dl> -<dt><code>-dPermissions=</code><em>number</em></dt> -<dd>Defines the PDF permissions flag field. Negative values are allowed -to represent unsigned integers with the highest bit set. See the PDF -Reference manual for the meaning of the flag bits.</dd> -</dl> - -<dl> -<dt><code>-dEncryptionR=</code><em>number</em></dt> -<dd>Defines the encryption method revision number - either 2 or 3.</dd> -</dl> - -<dl> -<dt><code>-dKeyLength=</code><em>number</em></dt> -<dd>Defines the length (in bits) of the encryption key. -Must be a multiple of 8 in the interval [40, 128]. -If the length isn't 40, <code>-dEncryptionR</code> must be 3.</dd> -</dl> - - -<h4><a name="Metadata"></a> -The following switches are used for generating metadata according to the Adobe XMP specification : -</h4> - -<dl> -<dt><code>-sDocumentUUID=</code><em>string</em></dt> -<dd>Defines a DocumentID to be included into the document Metadata. -If not specified, Ghostscript generates an UUID automatically. -Otherwise the specified string is copied into the document without -checking its syntax or consistence. -<p> -Note that Adobe XMP specification requires DocumentID must be same -for all versions of a document. Since Ghostscript does not provide -a maintenance of document versions, users are responsible to provide -a correct UUID through this parameter. -<p> -Note that Ghostscript has no assess to the host node ID -due to a minimization of platform dependent modules. -Therefore it uses an MD5 hash of the document contents for generating UUIDs.</p> -</dl> - -<dl> -<dt><code>-sInstanceUUID=</code><em>string</em> -<dd>Defines a instance ID to be included into the document Metadata. -If not specified, Ghostscript generates an UUID automatically. -Otherwise the specified string is copied into the document without -checking its syntax or consistence. -<p> -Note that the Adobe XMP specification requires the instance ID to be unique -for all versions of the document. This parameter may be used to disable -unique ID generation for debug purposes. - -<p> -When none of <code>DocumentUUID</code> -and <code>InstanceUUID</code> are specified, -the generated DocumentID appears same as instance ID. -</dl> - -<dl> -<dt><code>-sDocumentTimeSeq=</code><em>integer</em> -<dd>Defines an integer to be used as a deconflictor for generating -UUIDs, when several invocations of Ghostscript create -several PDF documents within same clock quantum (tick). -Mainly reserved for very fast computers and/or multithreading applications, -which may appear in future. If both <code>DocumentUUID</code> -and <code>InstanceUUID</code> are specified, <code>DocumentTimeSeq</code> is ignored. -</dl> - -<dl> -<dt><code>-sDSCEncoding=</code><em>string</em> -<dd>Defines the name of a Postscript encoding in which -DSC comments in the source document are encoded. -If specified, the comments are converted -from that encoding into Unicode UTF-8 when writing <code>Metadata</code>. -If not specified, the comments are copied to <code>Metadata</code> -with no conversion. Note that Adobe Distiller for -Windows uses the default locale's code page -for this translation, so it's result may differ from Ghostscript. -Adobe Acrobat appears to use <code>PDFDocEncoding</code> when -displaying document's properties, -so we recommend this value. -</dl> - -<dl> - -<dt><a name="UseOCR"></a><code>-sUseOCR=</code><em>string</em> -<dd>Controls the use of OCR in pdfwrite. If enabled this will use an OCR -engine to analyse the glyph bitmaps used to draw text in a PDF file, and -the resulting Unicode code points are then used to construct a ToUnicode -CMap. -<p> -PDF files containing ToUnicode CMaps can be searched, use copy/paste and -extract the text, subject to the accuracy of the ToUnicode CMap. Since not all -PDF files contain these it can be beneficial to create them. -</p> -<p> -Note that, for English text, it is possible that the existing standard character -encoding (which most PDF consumers will fall back to in the absence of Unicode -information) is better than using OCR, as OCR is not a 100% reliable process. -OCR processing is also comparatively slow. -</p> -<p> -For the reasons above it is useful to be able to exercise some control over the -action of pdfwrite when OCR processing is available, and the <code>UseOCR</code> -parameter provides that control. There are three possible values: -</p> -<ul> -<li><code>Never</code> Default - don't use OCR at all even if support is built-in.</li> -<li><code>AsNeeded</code> If there is no existing ToUnicode information, use OCR.</li> -<li><code>Always</code> Ignore any existing information and always use OCR.</li> -</ul> -<p> -Our experimentation with the Tesseract OCR engine has shown that the more text we -can supply for the engine to look at, the better the result we get. We are, unfortunately, -limited to the graphics library operations for text as follows. -</p> -<p> -The code works on text 'fragments'; these are the text sequences sent to the text -operators of the source language. Generally most input languages will try to send -text in its simplest form, eg "Hello", but the requirements of justification, kerning -and so on mean that sometimes each character is positioned independently on the page. -</p> -<p> -So pdfwrite renders all the bitmaps for every charcter in the text document, when -set up to use OCR. Later, if any character in the font does not have a Unicode -value already we use the bitmaps to assemble a 'strip' of text which we then send -to the OCR engine. If the engine returns a different number of recognised characters -than we expected then we ignore that result. We've found that (for English text) -constructions such as ". The" tend to ignore the full stop, presumably because the OCR -engine thinks that it is simply noise. In contrast "text." does identify the full -stop correctly. So by ignoring the failed result we can potentially get a better result -later in the document. -</p> -<p> -Obviously this is all heuristic and undoubtedly there is more we can do to improve the -functionality here, but we need concrete examples to work from. -</p> -</dd> -</dt> -</dl> - -<h3><a name="PS"></a>PostScript file output</h3> -<p> -The <code>ps2write</code> device handles the same set of distiller -parameters as -are handled by the <code>pdfwrite</code> device (and 2 unique extensions, see below). -<p> -The option <code>-dMaxInlineImageSize=</code><em>integer</em> -must not be used with <code>ps2write</code> as all images are inline in PostScript. -</p> - -<a name="AdditionalDistillerParams"></a> -<p> -There are also two additional (not Adobe-standard) Distiller parameters, specific to ps2write: -<dl> -<dt> -<code>/PSDocOptions</code><em> string</em> -<dd>No default value. If defined, the contents of the string will be emitted in the output PostScript prolog -enclosed within %%BeginSetup and %%EndSetup comments. This is intended as a means of introducing device-specific document wide -setup or configuration options into the output. Default media selection, printer resolution etc might be included here. - -<code>/PSPageOptions</code><em> array of strings</em> -</dd> -<dd>No default value. If defined, the contents of the strings in the array will be emitted in the output PostScript at the start -of each page, one string per page, enclosed within %%BeginPageSetup and %%EndPageSetup comments. This is intended as a means of introducing device-specific -setup or configuration options into the output on a page by page basis. The strings are used from the array sequentially, if there are more -pages than strings then we 'wrap round' and start again with the first string. This makes it convenient to do setup for even/odd pages -by simply including 2 strings in the array. - -<p> -Note: executing setpagedevice will reset distiller parameters to the default, if you use any of these options via setdistillerparams, and - expect to execute setpagedevice, you should set /LockDistillerParams true. Ordinarily the PDF interpreter executes setpagedevice for - every page in order to set the media size. -</p> -</dd> -</dt> -</dl> - -<p> -NB the strings contained in PSDocOptions, and the PSPageOptions array, are written verbatim to the output. No error checking is (or can be) performed on these strings -and it is the users responsibility to ensure they contain well formed PostScript which does not cause errors on the target device. -</p> -</p> -<p> -There are also the following ps2write specific options : -<p> - -<dl> -<dt> -<code>-dProduceDSC=</code><em>boolean</em> -<dd> Default value is true. When this value is true the output PostScript file will be constructed in a way which is compatible with the Adobe Document Structuring Convention, and will include a set of comments appropriate for use by document managers. This enables features such as page extraction, N-up printing and so on to be performed. When set to false, the output file will not be DSC-compliant. Older versions of Ghostscript cannot produce DSC-compliant output from ps2write, and the behaviour for these older versions matches the case when <code>ProduceDSC</code> is false. -</dl> - -<dl> -<dt> -<code>-dCompressEntireFile=</code><em>boolean</em> -<dd>When this parameter is true, the <code>LZWEncode</code> -and <code>ASCII85Encode</code> filters will be applied to the entire output file. -In this case <code>CompressPages</code> should be false to prevent a dual compression. -When this parameter is false, these filters will be applied to the initial procset only, -if <code>CompressPages</code> is true. -Default value is <code>false</code>. -</dl> -<p> -Note: It is not possible to set <code>CompressEntireFile</code> when <code>ProduceDSC</code> is true as a single compressed object cannot conform to the DSC. It is possible to set <code>CompressPages</code> which will also compress the ps2write ProcSet. -</p> -<h4><a name="printer_control"></a>Controlling device-specific behavior</h4> - -<p> -A few options can be used to influence the behavior of a printer or -PostScript interpreter that reads the result of ps2ps2. All of these options -are incompatible with DSC-compliant PostScript, in order to use any of them -<code>ProduceDSC</code> must be set to false. - -<dl> -<dt><code>-dRotatePages=</code><em>boolean</em>. -<dd>The printer will rotate pages -for a better fit with the physical size. Default value : <em>false</em>. -Must be <em>false</em> if <code>-dSetPageSize=true</code>. - -<dt><code>-dFitPages=</code><em>boolean</em>. -<dd>The printer will scale pages down -to better fit the physical page size. The rendering quality may be poor due to the scaling, -especially for fonts which Ghostscript had converted into bitmaps -(see the <em>ps2write</em> device parameter <code>HaveTrueTypes</code>; -See <a href="#Options">Options</a> about the <code>PageSize</code> entry of the <code>Policies</code> -dictionary while the conversion step). -Default value : <em>false</em>. -Must be <em>false</em> if <code>-dSetPageSize=true</code> or <code>-dCenterPages=true</code>. - -<dt><code>-dCenterPages=</code><em>boolean</em>. -<dd>The printer will center the page image on the selected media. Compatible with <code>-dRotatePages=true</code>, which may rotate the image on the media if it fits better, and then center it. -Default value : <em>false</em>. -Must be <em>false</em> if <code>-dSetPageSize=true</code> or <code>-dFitPages=true</code>. - -<dt><code>-dSetPageSize=</code><em>boolean</em>. -<dd>The printer will try to set page size from the job. -Only use with printers which can handle random <em>PageSize</em>. -Defaults to <em>true</em>, must be <em>false</em> if <code>-dRotatePages=true</code>, <code>-dCenterPages=true</code> or <code>-dFitPages=true</code>. - -<dt><code>-dDoNumCopies=</code><em>boolean</em>. -<dd>The PostScript emitted by ps2write will try to use copypage to create the number of copies originally requested. Note that this relies on the level 2 semantics for copypage -and will not reliably work on language level 3 devices (such as Ghostscript itself). -Defaults to false. This flag is not compatible with the ProduceDSC flag which will take precedence if set. - -</dl> - -<p> -These correspond to keys in the Postscript <em>userdict</em> -of the target printer's virtual memory to control its behavior while -executing a job generated with <code>ps2write</code>. - -<p> -These keys can be set when executing using the ps2write device, -this 'fixes' the resulting behaviour according to which key has been set. -If these keys are not defined during conversion, the resulting PostScript -will not attempt any form of media selection. - -In this case the behaviour can then be modified by setting the keys, either by modifying the resulting -PostScript or setting the values in some other manner on the target device. - -<p> -See also the distiller params PSDocOptions and PSPageOptions mentioned <a href="#AdditionalDistillerParams">above.</a></p> - -<h3><a name="EPS"></a>Encapsulated PostScript (EPS) file output</h3> - -<p> -The eps2write device is the same as the ps2write device, except that it produces Encapsulated PostScript, which is intended -to be imported into another document and treated as a 'black box'. There are certain restrictions which EPS -files must follow, the primary one being that they must be DSC conformant. This means that you must not set <code>-dProduceDSC</code> -to false. -<p>In addition EPS files may only contain a single page and may not contain device-specific PostScript. You should therefore not -use the <code>PSDocOptions</code> or <code>PSPageOptions</code> or any of the switches noted in the ps2write section -above under <a href="#printer_control">Controlling device specific behaviour</a> -</p> -<hr> -<h2><a name="PDFX"></a>Creating a PDF/X-3 document</h2> - -<p> - -To create a PDF/X-3 document from a Postscript or a PDF file, you should : - -<ul> -<li> Specify the <code>pdfwrite</code> device or use the <code>ps2pdf</code> script. -<li> Specify the <code>-dPDFX</code> option. It provides the document conformity - and forces <code>-dCompatibilityLevel=1.3</code>. -<li> Specify <code>-sColorConversionStrategy=Gray</code>, <code>-sColorConversionStrategy=CMYK</code> - or <code>-sColorConversionStrategy=UseDeviceIndependentColor</code>(<code>RGB</code> is not allowed). - If you plan to create a device-independent color PDF file then you should set the ProcessColorModel - using <code>-sProcessColorModel=DeviceGray</code> or <code>-sProcessColorModel=DeviceCMYK</code>. -<li> Specify a PDF/X definition file before running the input document. - It provides additional information to be included into the output document. - A sample PDF/X definition file may be found in <code>gs/lib/PDFX_def.ps</code>. - You will need to modify the content of this file; in particular you must alter the - /ICCProfile so that it points to a valid ICC profile for your OutputCondition. The - string '(...)' defining the ICCProfile must be a fully qualified device and path - specification appropriate for your Operating System. -<li> If a registered printing condition is applicable, specify its identifier - in the PDF/X definition file. Otherwise provide an ICC profile and - specify it in the PDF/X definition file as explained below. -<li> Provide a <code>DefaultRGB</code> resource file in the ColorSpace resource category. - Either define it in the PDF/X definition file, or provide - a definition of <code>gs/Resource/ColorSpace/DefaultRGB</code> . - <code>gs/Resource/ColorSpace/DefaultRGB</code> is usually - distributed with Ghostscript, its content may not necessarily satisfy your needs, see below. -</ul> - -<p> -NOTE: Unless <code>-dNOSAFER</code> is specified (NOT reccomended!) -the ICC profile will be read using the <code>SAFER</code> file permissions; you must ensure that the profile is -in a directory which is readable according to the <code>SAFER</code> permissions, or that the file itself -is specifically made readable. See Use.htm for details of how to set file permissions for <code>SAFER</code>. -</p> - -<p> -As mentioned above, the PDF/X definition file provides special information, -which the PDF/X-3 standard requires. You can find a sample file in -<code>gs/lib/PDFX_def.ps</code>, and edit it according to your needs. -The file follows Postscript syntax and uses the operator <code>pdfmark</code> -to pass the special information. To ease customisation -the lines likely to need editing in the sample file are marked with the comment <code>% Customize</code>. -They are explained below. - -<dl> -<dt><code>OutputCondition</code> <em>string</em> -<dd>Defines an <code>OutputCondition</code> value for the output intent dictionary. -</dl> - - -<dl> -<dt><code>OutputConditionIdentifier</code> <em>string</em> -<dd>Defines an <code>OutputConditionIdentifier</code> value for the output intent dictionary. -</dl> - -<dl> -<dt><code>ICCProfile</code> <em>string</em> -<dd> May be omitted if <code>OutputConditionIdentifier</code> -specifies a registered identifier of characterized printing condition -(see http://www.color.org/IPA_2003-11_PDFX.pdf). -Defines a file name of an ICC profile file to be included into the output document. -You may specify either an absolute file name, or a relative -path from the working directory. -</dl> - -<dl> -<dt><code>Title</code> <em>string</em> -<dd>Defines the document title. Only useful if the source Postscript file doesn't -define a title with DSC comments. Otherwise remove entire line from definition file. -</dl> - -<dl> -<dt><code>Info</code> <em>string</em> -<dd>Defines an <code>Info</code> value for the output intent dictionary. -</dl> - -<p>The Ghostscript distribution does not contain an ICC profile to be used -for creating a PDF/X-3 document. Users should either create an appropriate one themselves, -or use one from a public domain, or create one with the PDF/X-3 inspector freeware. - -<p>The PDF/X-3 standard requires a <code>TrimBox</code> entry -to be written for all page descriptions. -This is an array of four offsets -that specify how the page is to be trimmed -after it has been printed. -It is set to the same as <code>MediaBox</code> by default -unless the <code>PDFXTrimBoxToMediaBoxOffset</code> -distiller parameter is present. -It accepts offsets to the <code>MediaBox</code> as an array -[<i>left right top bottom</i>], -e.g., the PostScript input code -<code><< /PDFXTrimBoxToMediaBoxOffset -[10 20 30 40] >> setdistillerparams</code> -specifies that 10 points will be trimmed at the left, -20 points at the right, -30 points at the top, -and 40 points at the bottom. - -<p>Another page entry is the <code>BleedBox</code>. -It gives the area of the page -to which actual output items may extend; -cut marks, color bars etc. -must be positioned in the area between the <code>BleedBox</code> -and the <code>MediaBox</code>. -The <code>TrimBox</code> is always contained within the -<code>BleedBox</code>. -By default, -the <code>PDFXSetBleedBoxToMediaBox</code> distiller parameter -is <code>true</code>, -and the <code>BleedBox</code> is set to the same values -as the <code>MediaBox</code>. -If it is set to <code>false</code>, -the <code>PDFXBleedBoxToTrimBoxOffset</code> -parameter gives offset to the <code>TrimBox</code>. -It accepts a four-value array in the same format as the -<code>PDFXTrimBoxToMediaBoxOffset</code> parameter. - -<p> - -Here is a sample command line to invoke Ghostscript for generating a PDF/X-3 document : -<blockquote><code> -gs -dPDFX -dBATCH -dNOPAUSE -sColorConversionStrategy=CMYK -sDEVICE=pdfwrite -sOutputFile=out-x3.pdf PDFX_def.ps input.ps -</code></blockquote> - -<p> -Please also see the <code>PDFACompatibilityPolicy</code> control described under "Creating a PDF/A document" below. The same control is now used to specify the desired behaviour when an input file cannot be converted 'as is' into a PDF/X file. -<p> - -<hr> -<h2><a name="PDFA"></a>Creating a PDF/A document</h2> - -<p> -To create a PDF/A document, please follow the instructions for <a href="#PDFX">creating a PDF/X-3 document</a>, -with the following exceptions : - -<ul> -<li> Specify the <code>pdfwrite</code> device or use the <code>ps2pdf</code> script. -<li> Specify the <code>-dPDFA</code> option to specify PDF/A-1, <code>-dPDFA=2</code> for PDF/A-2 or <code>-dPDFA=3</code> for PDF/A-3 -<li> Specify <code>-sColorConversionStrategy=RGB</code>, <code>-sColorConversionStrategy=CMYK</code> - or <code>-sColorConversionStrategy=UseDeviceIndependentColor</code>. - If you plan to create a device-independent color PDF file then you should set the ProcessColorModel - using <code>-sProcessColorModel=DeviceRGB</code> or <code>-sProcessColorModel=DeviceCMYK</code>. -<li> Specify a PDF/A definition file before running the input document. - It provides additional information to be included in the output document. - A sample PDF/A definition file may be found in <code>gs/lib/PDFA_def.ps</code>. - You will need to modify the content of this file; in particular you must alter the - /ICCProfile so that it points to a valid ICC profile for your OutputIntent. The - string '(...)' defining the ICCProfile must be a fully qualified device and path - specification appropriate for your Operating System. -</ul> - -There is one additional control for PDF/A output: - -<dl> -<dt><code>PDFACompatibilityPolicy</code> <em>integer</em> -<dd>When an operation (eg pdfmark) is encountered which cannot be emitted in a PDF/A compliant file, this policy is consulted, there are currently three possible values: - -<blockquote>0 - (default) Include the feature or operation in the output file, the file will not be PDF/A compliant. Because the document Catalog is emitted before this is encountered, the file will still contain PDF/A metadata but will not be compliant. A warning will be emitted in this case. -</blockquote> -<dd> -<blockquote>1 - The feature or operation is ignored, the resulting PDF file will be PDF/A compliant. A warning will be emitted for every elided feature. -</blockquote> -<dd> -<blockquote>2 - Processing of the file is aborted with an error, the exact error may vary -depending on the nature of the PDF/A incompatibility. -</blockquote> -</dl> - -Here is a sample command line to invoke Ghostscript for generating a PDF/A document : -<blockquote><code> -gs -dPDFA=1 -dBATCH -dNOPAUSE -sColorConversionStrategy=RGB -sDEVICE=pdfwrite -sOutputFile=out-a.pdf PDFA_def.ps input.ps -</code></blockquote> - -<p> - -<hr> -<h2><a name="PPD"></a>Ghostscript PDF Printer Description</h2> -<p> -To assist with creating a PostScript file suitable for conversion -to PDF, ghostscript includes <a href="../lib/ghostpdf.ppd">ghostpdf.ppd</a>, -a PostScript Printer Description (PPD) file. -This allows some <a href="#Options">distiller parameters</a> -to be set when a PostScript file is generated. - -<h3>Windows XP or 2000</h3> -<p> -To install a "Ghostscript PDF" printer on Windows XP, -select the Windows Control Panel, -Printers and Faxes, -Add a Printer, -Local Printer, -Use port FILE: (Print to File), -Have Disk..., -select the directory containing -<a href="../lib/ghostpdf.ppd">ghostpdf.ppd</a> -and -<a href="../lib/ghostpdf.inf">ghostpdf.inf</a>, -select "Ghostscript PDF", -Replace existing driver (if asked), -and answer the remaining questions appropriately. -After installing, open the "Ghostscript PDF" properties, -select the Device Settings tab, -set "Minimum Font Size to Download as Outline" to 0 pixels. -<p> -To set distiller parameters, select the "Ghostscript PDF" -Printing Preferences, then the Advanced button. -The PDF settings are under "Printer Features". - - -<hr> -<h2><a name="Extensions"></a>pdfmark extensions</h2> -<p> -In order to better support the ZugFERD electronic invoice standard (http://www.ferd-net.de/front_content.php?idcat=231&changelang=4) -and potentially other standards in the future, a new non-standard pdfmark has been defined for use by pdfwrite. -</p> -<p> -This pdfmark allows additional Metadata to be defined which will be inserted into the Metadata generated by -the pdfwrite device. This is necessary because the standard requires a PDF/A-3 file be produced, with an extension -schema (and some additional XML data) contained within the Metadata referenced from the Catalog object. -</p> -<p> -While it would be possible to use the existing Metadata pdfmark to write a completely new set of metadata -into the Catalog, creating a conformant set of XML, with all the information synchronised with the /Info -dictionary would be challenging, this pdfmark allows the pdfwrite device to generate all the normal information -leaving the user with only the task of specifying the additional data. - -<code>[ /XML (string containing additional XMP data) /Ext_Metadata pdfmark</code> -</p> - -<hr> -<h2><a name="Limitations"></a>Limitations</h2> - -<p> -<code>The pdfwrite family</code> will sometimes convert input constructs to -lower-level ones, even if a higher-level construct is available. For -example, if the PostScript file uses <code>charpath</code> to set a -clipping path consisting of text, <code>pdfwrite</code> may write the -clipping path as a path in the PDF file, rather than as text, even though -PDF is able to express clipping with text. This is only a performance -issue, and will be improved incrementally over time. - -<p> -Some applications, such as HIGZ, produce PostScript files that use -ridiculously large coordinates. On such files, <code>pdfwrite</code> may -cause a <code>limitcheck</code> error. If this occurs, try reducing the -default internal resolution of 720 dpi by using the <code>-r</code> -switch, e.g., <code>-r300 somefile.ps</code>. - -<p> -<code>pdfwrite</code> ignores the PDF 1.3 (Acrobat 4.x) pdfmarks related to -document content structure: <code>StRoleMap</code>, -<code>StClassMap</code>, <code>StPNE</code>, -<code>StBookmarkRoot</code>, <code>StPush</code>, -<code>StPop</code>, <code>StPopAll</code>, <code>StBMC</code>, -<code>StBDC</code>, <code>EMC</code>, <code>StOBJ</code>, -<code>StAttr</code>, <code>StStore</code>, <code>StRetrieve</code>, -<code>NamespacePush</code>, <code>NamespacePop</code>, and -<code>NI</code>. While this causes some structural information to be -omitted from the output file, the displayed and printed output are normally -not affected. - -<!-- [2.0 end contents] ==================================================== --> - -<!-- [3.0 begin visible trailer] =========================================== --> -<hr> - -<p> -<small>Copyright © 2000-2022 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> |