1<h2 class='title'><a name='BASICS'>Printer Driver Basics</a></h2> 2 3<p>A CUPS raster printer driver consists of a PostScript Printer Description (PPD) file that describes the features and capabilities of the device, one or more <em>filter</em> programs that prepare print data for the device, and zero or more support files for color management, online help, and so forth. The PPD file includes references to all of the filters and support files used by the driver.</p> 4 5<p>Every time a user prints something the scheduler program, <a href='man-cupsd.html'>cupsd(8)</a>, determines the format of the print job and the programs required to convert that job into something the printer understands. CUPS includes filter programs for many common formats, for example to convert Portable Document Format (PDF) files into CUPS raster data. <a href='#FIGURE_1'>Figure 1</a> shows the data flow of a typical print job.</p> 6 7<div class='figure'><table summary='Raster Filter Chain'> 8<caption>Figure 1: <a name='FIGURE_1'>Raster Filter Chain</a></caption> 9<tr><td><img src='../images/cups-raster-chain.png' width='700' height='150' alt='Raster Filter Chain'></td></tr> 10</table></div> 11 12<p>The raster filter converts CUPS raster data into a format the printer understands, for example HP-PCL. CUPS includes several sample raster filters supporting standard page description languages (PDLs). <a href='#TABLE_1'>Table 1</a> shows the raster filters that are bundled with CUPS and the languages they support.</p> 13 14<div class='table'><table summary='Standard CUPS Raster Filters'> 15<caption>Table 1: <a name='TABLE_1'>Standard CUPS Raster Filters</a></caption> 16<thead> 17<tr><th>Filter</th><th>PDLs</th><th>ppdc DriverType</th><th>ppdc #include file</th></tr> 18</thead> 19<tbody> 20<tr><td>rastertoepson</td><td>ESC/P, ESC/P2</td><td>epson</td><td>epson.h</td></tr> 21<tr><td>rastertoescpx</td><td>ESC/P, ESC/P2, EPSON Remote Mode</td><td>escp</td><td>escp.h</td></tr> 22<tr><td>rastertohp</td><td>HP-PCL3, HP-PCL5</td><td>hp</td><td>hp.h</td></tr> 23<tr><td>rastertolabel</td><td>CPCL, Dymo, EPL1, EPL2, Intellitech PCL, ZPL</td><td>label</td><td>label.h</td></tr> 24<tr><td>rastertopclx</td><td>HP-RTL, HP-PCL3, HP-PCL3GUI, HP-PCL5, HP-PCL5c, HP-PCL5e</td><td>pcl</td><td>pcl.h</td></tr> 25</tbody> 26</table></div> 27 28<p>The optional port monitor handles interface-specific protocol or encoding issues. For example, some raster printers use the 1284.4 communications protocol.</p> 29 30<p>The backend handles communications with the printer, sending print data from the last filter to the printer and relaying back-channel data from the printer to the upstream filters. CUPS includes backend programs for common direct-connect interfaces and network protocols, and you can provide your own backend to support custom interfaces and protocols.</p> 31 32<p>The scheduler also supports a special "command" file format for sending maintenance commands and status queries to a printer or printer driver. Command print jobs typically use a single command filter program defined in the PPD file to generate the appropriate printer commands and handle any responses from the printer. <a href='#FIGURE_2'>Figure 2</a> shows the data flow of a typical command job.</p> 33 34<div class='figure'><table summary='Command Filter Chain'> 35<caption>Figure 2: <a name='FIGURE_2'>Command Filter Chain</a></caption> 36<tr><td><img src='../images/cups-command-chain.png' width='575' height='150' alt='Command Filter Chain'></td></tr> 37</table></div> 38 39<p>Raster printer drivers must provide their own command filter.</p> 40 41 42<h2 class='title'><a name='CREATING'>Creating New PPD Files</a></h2> 43 44<p>We recommend using the CUPS PPD compiler, <a href='man-ppdc.html'>ppdc(1)</a>, to create new PPD files since it manages many of the tedious (and error-prone!) details of paper sizes and localization for you. It also allows you to easily support multiple devices from a single source file. For more information see the "<a href='ppd-compiler.html'>Introduction to the PPD Compiler</a>" document. <a href='#LISTING_1'>Listing 1</a> shows a driver information file for several similar black-and-white HP-PCL5 laser printers.</p> 45 46<p class='example'>Listing 1: <a name='LISTING_1'>"examples/laserjet-basic.drv"</a></p> 47 48<pre class='example'> 49<I>// Include standard font and media definitions</I> 50<a href='ref-ppdcfile.html#_include'>#include</a> <font.defs> 51<a href='ref-ppdcfile.html#_include'>#include</a> <media.defs> 52 53<I>// Include HP-PCL driver definitions</I> 54<a href='ref-ppdcfile.html#_include'>#include</a> <pcl.h> 55 56<I>// Specify that this driver uses the HP-PCL driver...</I> 57<a href='ref-ppdcfile.html#DriverType'>DriverType</a> pcl 58 59<I>// Specify the driver options via the model number...</I> 60<a href='ref-ppdcfile.html#ModelNumber'>ModelNumber</a> ($PCL_PAPER_SIZE $PCL_PJL $PCL_PJL_RESOLUTION) 61 62<I>// List the fonts that are supported, in this case all standard fonts...</I> 63<a href='ref-ppdcfile.html#Font'>Font</a> * 64 65<I>// Manufacturer and driver version</I> 66<a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "HP" 67<a href='ref-ppdcfile.html#Version'>Version</a> 1.0 68 69<I>// Supported page sizes and their margins</I> 70<a href='ref-ppdcfile.html#HWMargins'>HWMargins</a> 18 12 18 12 71*<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter 72<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Legal 73<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Executive 74<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Monarch 75<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Statement 76<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> FanFoldGermanLegal 77 78<a href='ref-ppdcfile.html#HWMargins'>HWMargins</a> 18 12.72 18 12.72 79<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Env10 80 81<a href='ref-ppdcfile.html#HWMargins'>HWMargins</a> 9.72 12 9.72 12 82<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4 83<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A5 84<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> B5 85<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> EnvC5 86<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> EnvDL 87<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> EnvISOB5 88<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Postcard 89<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> DoublePostcard 90 91<I>// Only black-and-white output with mode 3 compression...</I> 92<a href='ref-ppdcfile.html#ColorModel'>ColorModel</a> Gray k chunky 3 93 94<I>// Supported resolutions</I> 95<a href='ref-ppdcfile.html#Resolution'>Resolution</a> - 1 0 0 0 "300dpi/300 DPI" 96*<a href='ref-ppdcfile.html#Resolution'>Resolution</a> - 8 0 0 0 "600dpi/600 DPI" 97 98<I>// Supported input slots</I> 99*<a href='ref-ppdcfile.html#InputSlot'>InputSlot</a> 7 "Auto/Automatic Selection" 100<a href='ref-ppdcfile.html#InputSlot'>InputSlot</a> 2 "Manual/Tray 1 - Manual Feed" 101<a href='ref-ppdcfile.html#InputSlot'>InputSlot</a> 4 "Upper/Tray 1" 102<a href='ref-ppdcfile.html#InputSlot'>InputSlot</a> 1 "Lower/Tray 2" 103<a href='ref-ppdcfile.html#InputSlot'>InputSlot</a> 5 "LargeCapacity/Tray 3" 104 105<I>// Tray 3 is an option...</I> 106<a href='ref-ppdcfile.html#Installable'>Installable</a> "OptionLargeCapacity/Tray 3 Installed" 107<a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*OptionLargeCapacity False *InputSlot LargeCapacity" 108 109{ 110 <I>// HP LaserJet 2100 Series</I> 111 <a href='ref-ppdcfile.html#Throughput'>Throughput</a> 10 112 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "LaserJet 2100 Series" 113 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "hpljt211.ppd" 114} 115 116{ 117 <I>// LaserJet 2200 and 2300 series have duplexer option...</I> 118 <a href='ref-ppdcfile.html#Duplex'>Duplex</a> normal 119 <a href='ref-ppdcfile.html#Installable'>Installable</a> "OptionDuplex/Duplexer Installed" 120 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*OptionDuplex False *Duplex" 121 122 { 123 <I>// HP LaserJet 2200 Series</I> 124 <a href='ref-ppdcfile.html#Throughput'>Throughput</a> 19 125 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "LaserJet 2200 Series" 126 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "hpljt221.ppd" 127 } 128 129 { 130 <I>// HP LaserJet 2300 Series</I> 131 <a href='ref-ppdcfile.html#Throughput'>Throughput</a> 25 132 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "LaserJet 2300 Series" 133 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "hpljt231.ppd" 134 } 135} 136</pre> 137 138 139<h2 class='title'><a name='FILTERS'>Using Filters</a></h2> 140 141<p>The standard CUPS raster filters can be specified using the 142<a href='ref-ppdcfile.html#DriverType'><tt>DriverType</tt></a> directive, for example:</p> 143 144<pre class='example'> 145<I>// Specify that this driver uses the HP-PCL driver...</I> 146<a href='ref-ppdcfile.html#DriverType'>DriverType</a> pcl 147</pre> 148 149<p><a href='#TABLE_1'>Table 1</a> shows the driver types for each of the standard CUPS raster filters. For drivers that do not use the standard raster filters, the "custom" type is used with <a href='ref-ppdcfile.html#Filter'><tt>Filter</tt></a> directives:</p> 150 151<pre class='example'> 152<a href='ref-ppdcfile.html#DriverType'>DriverType</a> custom 153<a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 /path/to/raster/filter 154<a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-command 100 /path/to/command/filter 155</pre> 156 157 158<h2 class='title'><a name='COLOR'>Implementing Color Management</a></h2> 159 160<p>CUPS uses ICC color profiles to provide more accurate color reproduction. The <a href='spec-ppd.html#cupsICCProfile'><tt>cupsICCProfile</tt></a> attribute defines the color profiles that are available for a given printer, for example:</p> 161 162<pre class='example'> 163<a href='ref-ppdcfile.html#Attribute'>Attribute</a> cupsICCProfile "ColorModel.MediaType.Resolution/Description" /path/to/ICC/profile 164</pre> 165 166<p>where "ColorModel.MediaType.Resolution" defines a selector based on the corresponding option selections. A simple driver might only define profiles for the color models that are supported, for example a printer supporting Gray and RGB might use:</p> 167 168<pre class='example'> 169<a href='ref-ppdcfile.html#Attribute'>Attribute</a> cupsICCProfile "Gray../Grayscale Profile" /path/to/ICC/gray-profile 170<a href='ref-ppdcfile.html#Attribute'>Attribute</a> cupsICCProfile "RGB../Full Color Profile" /path/to/ICC/rgb-profile 171</pre> 172 173<p>The options used for profile selection can be customized using the <tt>cupsICCQualifier2</tt> and <tt>cupsICCQualifier3</tt> attributes.</p> 174 175<h3><span class='info'>Since macOS 10.5</span>Custom Color Matching Support</h3> 176 177<p>macOS printer drivers that are based on an existing standard RGB colorspace can tell the system to use the corresponding colorspace instead of an arbitrary ICC color profile when doing color management. The <a href='#APCustom'><tt>APSupportsCustomColorMatching</tt></a> and <tt>APDefaultCustomColorMatchingProfile</tt> attributes can be used to enable this mode:</p> 178 179<pre class='example'> 180<a href='ref-ppdcfile.html#Attribute'>Attribute</a> APSupportsCustomColorMatching "" true 181<a href='ref-ppdcfile.html#Attribute'>Attribute</a> APDefaultCustomColorMatchingProfile "" sRGB 182</pre> 183 184 185<h2 class='title'><a name='MACOSX'>Adding macOS Features</a></h2> 186 187<p>macOS printer drivers can provide <a href='spec-ppd.html#MACOSX'>additional attributes</a> to specify additional option panes in the print dialog, an image of the printer, a help book, and option presets for the driver software:</p> 188 189<pre class='example'> 190<a href='ref-ppdcfile.html#Attribute'>Attribute</a> APDialogExtension "" /Library/Printers/Vendor/filename.plugin 191<a href='ref-ppdcfile.html#Attribute'>Attribute</a> APHelpBook "" /Library/Printers/Vendor/filename.bundle 192<a href='ref-ppdcfile.html#Attribute'>Attribute</a> APPrinterIconPath "" /Library/Printers/Vendor/filename.icns 193<a href='ref-ppdcfile.html#Attribute'>Attribute</a> APPrinterPreset "name/text" "*option choice ..." 194</pre> 195
