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diff --git a/filter/api-raster.shtml b/filter/api-raster.shtml deleted file mode 100644 index 6d458a2ed..000000000 --- a/filter/api-raster.shtml +++ /dev/null @@ -1,158 +0,0 @@ -<!-- - Raster API introduction for CUPS. - - Copyright 2007-2013 by Apple Inc. - Copyright 1997-2006 by Easy Software Products, all rights reserved. - - These coded instructions, statements, and computer programs are the - property of Apple Inc. and are protected by Federal copyright - law. Distribution and use rights are outlined in the file "LICENSE.txt" - which should have been included with this file. If this file is - file is missing or damaged, see the license at "http://www.cups.org/". ---> - -<h2 class='title'><a name="OVERVIEW">Overview</a></h2> - -<p>The CUPS raster API provides a standard interface for reading and writing -CUPS raster streams which are used for printing to raster printers. Because the -raster format is updated from time to time, it is important to use this API to -avoid incompatibilities with newer versions of CUPS.</p> - -<p>Two kinds of CUPS filters use the CUPS raster API - raster image processor -(RIP) filters such as <code>pstoraster</code> and <code>cgpdftoraster</code> -(macOS) that produce CUPS raster files and printer driver filters that -convert CUPS raster files into a format usable by the printer. Printer -driver filters are by far the most common.</p> - -<p>CUPS raster files (<code>application/vnd.cups-raster</code>) consists of -a stream of raster page descriptions produced by one of the RIP filters such as -<var>pstoraster</var>, <var>imagetoraster</var>, or -<var>cgpdftoraster</var>. CUPS raster files are referred to using the -<a href='#cups_raster_t'><code>cups_raster_t</code></a> type and are -opened using the <a href='#cupsRasterOpen'><code>cupsRasterOpen</code></a> -function. For example, to read raster data from the standard input, open -file descriptor 0:</p> - -<pre class="example"> -#include <cups/raster.h> - -<a href="#cups_raster_t">cups_raster_t</a> *ras = <a href="#cupsRasterOpen">cupsRasterOpen</a>(0, CUPS_RASTER_READ); -</pre> - -<p>Each page of data begins with a page dictionary structure called -<a href="#cups_page_header2_t"><code>cups_page_header2_t</code></a>. This -structure contains the colorspace, bits per color, media size, media type, -hardware resolution, and so forth used for the page.</p> - -<blockquote><b>Note:</b> - - <p>Do not confuse the colorspace in the page header with the PPD - <tt>ColorModel</tt> keyword. <tt>ColorModel</tt> refers to the general type of - color used for a device (Gray, RGB, CMYK, DeviceN) and is often used to - select a particular colorspace for the page header along with the associate - color profile. The page header colorspace (<tt>cupsColorSpace</tt>) describes - both the type and organization of the color data, for example KCMY (black - first) instead of CMYK and RGBA (RGB + alpha) instead of RGB.</p> - -</blockquote> - -<p>You read the page header using the -<a href="#cupsRasterReadHeader2"><code>cupsRasterReadHeader2</code></a> -function:</p> - -<pre class="example"> -#include <cups/raster.h> - -<a href="#cups_raster_t">cups_raster_t</a> *ras = <a href="#cupsRasterOpen">cupsRasterOpen</a>(0, CUPS_RASTER_READ); -<a href="#cups_page_header2_t">cups_page_header2_t</a> header; - -while (<a href="#cupsRasterReadHeader2">cupsRasterReadHeader2</a>(ras, &header)) -{ - /* setup this page */ - - /* read raster data */ - - /* finish this page */ -} -</pre> - -<p>After the page dictionary comes the page data which is a full-resolution, -possibly compressed bitmap representing the page in the printer's output -colorspace. You read uncompressed raster data using the -<a href="#cupsRasterReadPixels"><code>cupsRasterReadPixels</code></a> -function. A <code>for</code> loop is normally used to read the page one line -at a time:</p> - -<pre class="example"> -#include <cups/raster.h> - -<a href="#cups_raster_t">cups_raster_t</a> *ras = <a href="#cupsRasterOpen">cupsRasterOpen</a>(0, CUPS_RASTER_READ); -<a href="#cups_page_header2_t">cups_page_header2_t</a> header; -int page = 0; -int y; -char *buffer; - -while (<a href="#cupsRasterReadHeader2">cupsRasterReadHeader2</a>(ras, &header)) -{ - /* setup this page */ - page ++; - fprintf(stderr, "PAGE: %d %d\n", page, header.NumCopies); - - /* allocate memory for 1 line */ - buffer = malloc(header.cupsBytesPerLine); - - /* read raster data */ - for (y = 0; y < header.cupsHeight; y ++) - { - if (<a href="#cupsRasterReadPixels">cupsRasterReadPixels</a>(ras, buffer, header.cupsBytesPerLine) == 0) - break; - - /* write raster data to printer on stdout */ - } - - /* finish this page */ -} -</pre> - -<p>When you are done reading the raster data, call the -<a href="#cupsRasterClose"><code>cupsRasterClose</code></a> function to free -the memory used to read the raster file:</p> - -<pre class="example"> -<a href="#cups_raster_t">cups_raster_t</a> *ras; - -<a href="#cupsRasterClose">cupsRasterClose</a>(ras); -</pre> - - -<h2 class='title'><a name="TASKS">Functions by Task</a></h2> - -<h3><a name="OPENCLOSE">Opening and Closing Raster Streams</a></h3> - -<ul class="code"> - - <li><a href="#cupsRasterClose" title="Close a raster stream.">cupsRasterClose</a></li> - <li><a href="#cupsRasterOpen" title="Open a raster stream.">cupsRasterOpen</a></li> - -</ul> - -<h3><a name="READING">Reading Raster Streams</a></h3> - -<ul class="code"> - - <li><a href="#cupsRasterReadHeader" title="Read a raster page header and store it in a version 1 page header structure.">cupsRasterReadHeader</a> <span class="info">Deprecated in CUPS 1.2/macOS 10.5</span></li> - <li><a href="#cupsRasterReadHeader2" title="Read a raster page header and store it in a version 2 page header structure.">cupsRasterReadHeader2</a></li> - <li><a href="#cupsRasterReadPixels" title="Read raster pixels.">cupsRasterReadPixels</a></li> - -</ul> - -<h3><a name="WRITING">Writing Raster Streams</a></h3> - -<ul class="code"> - - <li><a href="#cupsRasterInterpretPPD" title="Interpret PPD commands to create a page header.">cupsRasterInterpretPPD</a></li> - <li><a href="#cupsRasterWriteHeader" title="Write a raster page header from a version 1 page header structure.">cupsRasterWriteHeader</a> <span class="info">Deprecated in CUPS 1.2/macOS 10.5</span></li> - <li><a href="#cupsRasterWriteHeader2" title="Write a raster page header from a version 2 page header structure.">cupsRasterWriteHeader2</a></li> - <li><a href="#cupsRasterWritePixels" title="Write raster pixels.">cupsRasterWritePixels</a></li> - -</ul> |