
 <chapter><title>CUPS and Gimp-Print</title>
   <sect1><title>Introduction</title>
     <para>
       CUPS is an acronym which stands for <emphasis>C</emphasis>ommon
<emphasis>U</emphasis>nix <emphasis>P</emphasis>rinting
<emphasis>S</emphasis>ystem.  It is assumed that the reader has
properly installed the CUPS software and the Gimp-Print software.
This section will discuss adding a printer to CUPS that uses a
Gimp-Print printer driver, as well as how to modify the various
settings supplied by Gimp-Print. This will be a rather quick
explanation, as the CUPS software is quite well documented, and it is
not my intention to attempt to duplicate the CUPS documentation here.
     </para>
   </sect1>

   <sect1><title>CUPS Printer Installation</title>
     <para>
This explanation will use the web interface provided by CUPS. First,
aim your favorite web browser at
<ulink url="http://localhost:631">the CUPS server</ulink>.  The
following screen should appear within your browser.
    </para>

   <figure><title>The CUPS Startup Window</title>
   <mediaobject>
   <imageobject>
   <imagedata scale="45" fileref="figures/cups_startup.png" FORMAT="PNG">
   </imageobject>
   <textobject>
   <phrase>The CUPS Startup Window</phrase>
   </textobject>
   </mediaobject>
   </figure>

   <para>
Now, you may click on either the word <guilabel>Printers</guilabel> in the bar at the top
of the page, or you may click on the <guilabel>Manage Printers</guilabel> text.  In
either case, the next screen you see will look like this one if you
have not yet configured any printers.
   </para>

   <figure><title>The CUPS Printers Window</title>
   <mediaobject>
   <imageobject>
   <imagedata scale="45" fileref="figures/cups_printers.png" FORMAT="PNG">
   </imageobject>
   <textobject>
   <phrase>The CUPS Printers Window</phrase>
   </textobject>
   </mediaobject>
   </figure>

    <para>
At this time, click on the <guibutton>Add Printer</guibutton> button.
You will then see the Admin screen (shown below).
    </para>

   <figure><title>The CUPS Admin Window</title>
   <mediaobject>
   <imageobject>
   <imagedata scale="45" fileref="figures/cups_admin.png" FORMAT="PNG">
   </imageobject>
   <textobject>
   <phrase>The CUPS Admin Window</phrase>
   </textobject>
   </mediaobject>
   </figure>

   <para>
Notice in the screenshot that the three boxes are shown after the
author filled them in for his printer at home.  You will need to fill
in an appropriate name of your printer, its location, and a
description which meets your own needs.  Once this is done, click on
the <guibutton>Continue</guibutton> button, and then this screen will appear.
   </para>

   <figure id="fig-cups-admin-device"><title>The CUPS Admin Device Window</title>
   <mediaobject>
   <imageobject>
   <imagedata scale="35" fileref="figures/cups_admin_device.png" FORMAT="PNG">
   </imageobject>
   <textobject>
   <phrase>The CUPS Admin Device Window</phrase>
   </textobject>
   </mediaobject>
   </figure>

   <para>
Click on the drop down menu next to the word
<guilabel>Device</guilabel> and a list of possible printer devices
appears.  Select the device appropriate for your printer.  Note that
there are a range of serial, parallel, USB, and other devices from
which to choose.  Once the selection is made, click the
<guibutton>Continue</guibutton> button.  Now, this screen appears.
   </para>

   <figure><title>The CUPS Admin Model/Driver Window</title>
   <mediaobject>
   <imageobject>
   <imagedata scale="35" fileref="figures/cups_admin_make.png" FORMAT="PNG">
   </imageobject>
   <textobject>
   <phrase>The CUPS Admin Model/Driver Window</phrase>
   </textobject>
   </mediaobject>
   </figure>

   <caution>
   <title>Caution Regarding USB Printers</title>

   <para>
CUPS versions 1.1.11 and later <emphasis>REQUIRE</emphasis>
the user to insure that the desired USB printer is powered on
<emphasis>AND</emphasis> physically connected to the USB bus
<emphasis>BEFORE</emphasis> starting the CUPS software.  
   </para>
   <para>
CUPS must see the USB printer when the software starts.  The CUPS software
is typically started when the computer boots.  Note that one cannot
simply plug in the USB printer and power it on after CUPS has started.
(Note that this does not apply to parallel port printers).
   </para>
   <para>
If the USB printer was not connected and powered on at the time CUPS was
started, there will not be a USB printer shown in the
list of devices on the CUPS Admin Device Window (see 
<xref linkend="fig-cups-admin-device">).  In this event, stop the CUPS
software, properly connect and power on the USB printer, and restart
the CUPS software.
   </para>
   <para>
From the list of devices shown in the CUPS Admin Device Window
(see <xref linkend="fig-cups-admin-device">), a clever user might
attempt to avoid this issue by selecting 
<guimenuitem>Internet Printing Protocol</guimenuitem> 
and then enter something similar to 'usb:/dev/usblp0' in the next
screen.  However, this fails later in the configuration process with a
"client_error_not_possible" error message with no other explanation.
Note that entering 'file:/dev/usblp0' will not work either. While CUPS
will allow this, printing will not actually work in some situations.
   </para>
   <para>
CUPS versions 1.1.10 and earlier exhibit similar behavior with regard
to not displaying the USB printer if it was not connected to the USB
bus and powered up prior to starting the CUPS software.  However,
these versions of CUPS will indeed allow the user to enter the name of
the USB connection, unlike versions 1.1.11 and later.
   </para>
   </caution>

   <para>
Select the manufacturer of your printer and click the
<guibutton>Continue</guibutton> button.  A window will appear which
asks you to select the specific model number for your printer.
   </para>

   <para>
Scroll through the long list and find the model number for your
printer.  Notice carefully that there are many different languages
supported for each printer, as denoted by the initials in parenthesis.
(en) would be for English, (da) for Danish, (sv) for Swedish, (fr) for
French, (no) for Norwegian, (pl) for Polish, and (en_GB) for British
English (see <xref linkend="fig-cups-admin-model">).  Also take note
of the Gimp-Print revision for the driver, and ensure that it is
indeed the version of Gimp-Print which you have most recently
installed.  Once you have made the proper selection, click on the
<guibutton>Continue</guibutton> button. 
   </para>

   <figure id="fig-cups-admin-model"><title>The 2nd CUPS Admin Model/Driver Window</title>
   <mediaobject>
   <imageobject>
   <imagedata scale="55" fileref="figures/cups_admin_model.png" FORMAT="PNG">
   </imageobject>
   <textobject>
   <phrase>The 2nd CUPS Admin Model/Driver Window</phrase>
   </textobject>
   </mediaobject>
   </figure>

   <figure><title>The CUPS Admin Success Window</title>
   <mediaobject>
   <imageobject>
   <imagedata scale="39" fileref="figures/cups_admin_success.png" FORMAT="PNG">
   </imageobject>
   <textobject>
   <phrase>The CUPS Admin Success Window</phrase>
   </textobject>
   </mediaobject>
   </figure>

   <para>
Congratulations!  You should now see the CUPS window indicating that
your printer was successfully installed.  Notice the sentence which
reads "Printer your_printer has been added successfully".  Click on
your_printer, which will be the underlined name for your printer.
   </para>

   <figure id="fig-cups-my-printer"><title>The CUPS Window for Your Printer</title>
   <mediaobject>
   <imageobject>
   <imagedata scale="65" fileref="figures/cups_my_printer.png" FORMAT="PNG">
   </imageobject>
   <textobject>
   <phrase>The CUPS Window for Your Printer</phrase>
   </textobject>
   </mediaobject>
   </figure>

   <para>
After clicking on your_printer (epson_870 in this example), a window
will appear similar to that shown in <xref linkend="fig-cups-my-printer">.
It would probably be a good idea at this point to click on the
<guibutton>Print Test Page</guibutton> button to ensure that
everything is working properly.  Take note of the Gimp-Print revision
printed on this screen and confirm once again that it is the expected
revision.
   </para>

   </sect1>

   <sect1><title>Configuring your Printer in CUPS</title>

     <para>
With reference to <xref linkend="fig-cups-my-printer">, click
on the <guibutton>Configure Printer</guibutton> button.  A partial
screenshot of the printer configuration window appears in
<xref linkend="fig-cups-printer-config-window">.
The contents of this window will vary depending on precisely which
printer you selected when you configured CUPS for your printer.  The
screenshot shows the selections made by the author for his printer.
The individual selections will not be explained in detail here, as
they are the same selections which are available when using the
Gimp-Print plugin to the GIMP.  These selections are explained in
detail in various sections of <xref linkend="ch-gimp-and-gimp-print">.
   </para>

   <figure id="fig-cups-printer-config-window"><title>The CUPS Printer Cofiguration Window</title>
   <mediaobject>
   <imageobject>
   <imagedata scale="30" fileref="figures/cups_config_printer.png" FORMAT="PNG">
   </imageobject>
   <textobject>
   <phrase>The CUPS Printer Configuration Window</phrase>
   </textobject>
   </mediaobject>
   </figure>


   </sect1>

   <sect1><title>Using CUPS from the Command Line</title>

   <para>
    It is possible to use the CUPS printing system from the command
line.  While this document will not delve into all of the specifics of
the CUPS command line interface, there are portions of this interface
which are specific to the Gimp-Print software.
   </para>

   <para>
The command line is in some cases a more convenient way to generate
printed output (e.g. when printing from a script).  However, most
people (including the author) cannot easily predict what a command
line option of "-o stpCyan=1350" will do to the output.  It is
therefore a good idea to use the GIMP to view the image and the
Gimp-Print plugin to preview these settings before relying on the
command line.
   </para>

   <para>
When using CUPS from the command line, the command will have this
general format:

   <programlisting>
   <![ CDATA [
     lpr -P my_printer_name \
         -o option1=<choice1> \
         -o option2=<choice2> \
         /path/to/printfile
     ]]>
   </programlisting>

When typing the command directly onto the command line, put all of the
command line options on one line, and do not type the "\" characters.
The list of possible options which are specific to Gimp-Print,
followed by some of the supported choices, are shown below:

   <programlisting>
   <![ CDATA [
   -o PageSize=<...| A3 | A4 | A4 | ...>
   -o InputSlot=<Roll | Standard>
   -o MediaType=< ..| Inkjet | Plain | GlossyPaper | ...>
   -o Resolution=<360sw | 360swuni ...| 1440x720 >
   -o ColorModel=<Black | RGB | Gray | CMYK>
   -o stpBrightness=<0...2000>
   -o stpContrast=<0...2000>
   -o stpCyan=<0...4000>
   -o stpDensity=<0...2000>
   -o stpDither=<0...4000>
   -o stpGamma=<0...4000>
   -o stpImageType=<LineArt | Continuous | SolidTone>
   -o stpInkType=<PhotoCMY | CMYK | PhotoCMYK | RGB>
   -o stpMagenta=<0...4000>
   -o stpSaturation=<0...9000>
   -o stpYellow=<0...4000>
   ]]>
   </programlisting>

For more detailed information, consult the appropriate sections of <xref linkend="ch-gimp-and-gimp-print">.
   </para>

   </sect1>

 </chapter>
