<chapter id="ch-gimp-and-gimp-print"><title>GIMP and Gimp-Print</title>
<sect1>
<title>Running the GIMP</title>
<para>
This section assumes that you have the GIMP version 1.2 installed
and working properly on your computer, and that you have an image of
some type that you desire to print. To get started quickly, log into
your system, start the X window system, and bring up your favorite terminal
window. At the $ prompt, type:
<programlisting>
<![ CDATA [
$ gimp &
]]>
</programlisting>
This should start the GIMP for you. If it does not, check that
you have installed the GIMP properly, and that its binary is located
in one of the directories listed in your $PATH environment
variable. On the assumption that this worked, the screen should now
look something like this:
<figure><title>The Startup Window for The GIMP</title>
<mediaobject>
<imageobject>
<imagedata fileref="figures/gimp_startup.png" FORMAT="PNG">
</imageobject>
<textobject>
<phrase>Startup window for The GIMP</phrase>
</textobject>
</mediaobject>
</figure>
</para>
<para>
At this point, you should use the
<menuchoice>
<guimenu>File</guimenu>
<guimenuitem>Open</guimenuitem>
</menuchoice>
menu option to open your favorite picture. We will print this picture
shortly. Your picture should be displayed next to the GIMP startup
window, perhaps looking similar to the following (sssh! Don't tell
anybody the secret!):
<figure><title>A Sample Image Displayed by The GIMP</title>
<mediaobject>
<imageobject>
<imagedata scale="50" fileref="figures/gimp_image.png" FORMAT="PNG">
</imageobject>
<textobject>
<phrase>A Sample Image displayed by The Gimp</phrase>
</textobject>
</mediaobject>
</figure>
</para>
</sect1>
<sect1><title>The Gimp-Print Graphical User Interface</title>
<para>
Now that the GIMP is displaying your picture, put your mouse over
the picture and click the right mouse button. A menu will appear.
Choose the
<menuchoice>
<guimenu>File</guimenu>
<guimenuitem>Print</guimenuitem>
</menuchoice>
menu option. This will cause the Gimp-Print GUI window to appear (see
<xref linkend="fig-gimp-print-gui">). Move the mouse cursor
over the various parts of the Gimp-Print GUI window, and notice that
if you leave your mouse in one place for a short time without clicking
any buttons, a small box appears. This box contains helpful text.
These small boxes are called "tooltips" and are intended to remind you
about the function of each part of the graphical interface.
</para>
<para>
The next several sections will continuously refer to
<xref linkend="fig-gimp-print-gui"> and
<xref linkend="fig-gimp-print-gui-1">. The difference between
the two figures can be seen in the top right corner of the window.
Notice that there are two tabs, one which reads
<guilabel>Printer Settings</guilabel> and another which reads
<guilabel>Image/Output Settings</guilabel>. Notice also that the
window is divided into several major sections which directly map to
the major sections of this document:
<itemizedlist>
<listitem>
<para><link linkend="sec-preview">Preview</link></para>
</listitem>
<listitem>
<para><link linkend="sec-printer-settings">Printer Settings</link></para>
</listitem>
<listitem>
<para><link linkend="sec-printer-settings">Image/Output Settings</link></para>
</listitem>
<listitem>
<para><link linkend="sec-position">Position</link></para>
</listitem>
<listitem>
<para><link linkend="sec-scaling">Size</link></para>
</listitem>
<listitem>
<para><link linkend="sec-printing-and-saving-settings">Printing and Saving Settings</link></para>
</listitem>
</itemizedlist>
</para>
<figure id="fig-gimp-print-gui"><title>The Gimp-Print Graphical User Interface 1 (GUI)</title>
<mediaobject>
<imageobject>
<imagedata scale="40" fileref="figures/gimp-print-gui.png" FORMAT="PNG">
</imageobject>
<textobject>
<phrase>The GIMP Print GUI showing printer settings</phrase>
</textobject>
</mediaobject>
</figure>
<figure id="fig-gimp-print-gui-1"><title>The Gimp-Print Graphical User Interface 2 (GUI)</title>
<mediaobject>
<imageobject>
<imagedata scale="40" fileref="figures/gimp-print-gui-1.png" FORMAT="PNG">
</imageobject>
<textobject>
<phrase>The GIMP Print GUI showing image/output settings</phrase>
</textobject>
</mediaobject>
</figure>
<sect2><title id="sec-printer-settings">Printer Settings</title>
<indexterm id="idx-printer-settings"><primary>Printer Settings</primary></indexterm>
<sect3><title>Printer</title>
<para>
Click on the <guilabel>Printer Settings</guilabel> tab near the
top right hand corner of the window (see
<xref linkend="fig-gimp-print-gui">). Then, click on the downward
facing arrow to the right of the <guilabel>Printer</guilabel> combo
box to see a list of the system printer queues. Select the queue to which
you would like the printed image to be sent. One may also print the
image directly to a file by selecting <guimenuitem>File</guimenuitem>.
In this event, the user will be prompted for the filename when either the
<guibutton>Print</guibutton> button or the <guibutton>Print and Save
Settings</guibutton> button is clicked.
</para>
<para>
When either the <guibutton>Print and Save Settings</guibutton> button
or the <guibutton>Save Settings</guibutton> button is clicked,
the settings are saved in a file called
<filename>~/.gimp-1.2/printrc</filename>. The user is cautioned about
hand editing this file since it is generated by Gimp-Print (although
it was the only way that the author found for removing bogus entries
created while playing with the <guibutton>New Printer</guibutton> button).
</para>
</sect3>
<sect3><title>Setup Printer</title>
<para>
Before any useful printing can occur, the user needs to associate
the named printer with the
actual make and model of the printer. Click the
<guibutton>Setup Printer</guibutton> button in
the <guilabel>Printer</guilabel> section of the window (the upper
right, and just below the Printer display box). When this is done, the
following window appears:
<figure><title>The Setup Printer Window</title>
<mediaobject>
<imageobject>
<imagedata scale="60" fileref="figures/gimp-print-setup.png" FORMAT="PNG">
</imageobject>
<textobject>
<phrase>The Setup Printer Window</phrase>
</textobject>
</mediaobject>
</figure>
</para>
<para>
Scroll through the Printer Model section of the window until you
find a printer which matches yours. If you cannot find the precise
model, pick something close and hope for the best. There are selections
for a wide array of Postscript, inkjet, and laser printers. After you
have selected a printer, you will see the printer command displayed.
</para>
<para>
The Gimp-Print software does all of the necessary conversion of the
image to be printed into the language of your printer. It is
unnecessary and undesirable for any other sofware to manipulate this
data. (This is why the command contains the "-l" switch or the "-o
raw" switch). Please use care if you feel the need to edit this
command. Once you are satisfied with your selection, click the
<guibutton>OK</guibutton> button.
</para>
</sect3>
<sect3><title>New Printer</title>
<para>
In the previous sections, the user selected an existing printer
queue and associated a particular type of printer to that queue. For
most cases, this is probably all that is required. However, some
situations might require more detailed control over the handling of
the printer data.
</para>
<para>
Click the <guibutton>New Printer</guibutton> button to tell the
software that you wish to create a new name. In this case, the new
name may actually be an existing printer with different settings that
you wish to save, or it may simply be a name associated with a
particular command for handling the printer data. A window will
appear thus:
<figure><title>The New Printer Window</title>
<mediaobject>
<imageobject>
<imagedata fileref="figures/gimp-print-new-printer.png" FORMAT="PNG">
</imageobject>
<textobject>
<phrase>The New Printer Window</phrase>
</textobject>
</mediaobject>
</figure>
Type a name into the window and click <guibutton>OK</guibutton>
(or <guibutton>Cancel</guibutton> if you wish not to do this).
Notice that the new name now appears as the selected <guilabel>Printer</guilabel>.
As you change settings in the rest of the Gimp-Print GUI, they will be
associated with this printer name. When the settings are saved,
they can be recovered easily by simply selecting this named printer
from the Printer combo box.
</para>
<para>
One example where this feature might be used is as follows. The
author frequently prints photos on Epson 4x6 photo paper. Note that
this paper is physically larger than 4x6 and it has perforations on
all four sides. The author dislikes printing part of the image on the
perforated parts of the paper which will be removed after
printing the photo. By selecting the proper scaling percentage,
printing can be constrained to the 4x6 part of the paper which will
remain after the perforated sections are removed. The author has
saved this setting using this feature of the Gimp-Print software.
</para>
</sect3>
<sect3><title>Media Size</title>
<para>
The term <emphasis>media</emphasis> refers to paper, card stock,
envelopes, or whatever you have put into your printer onto which
something will be printed. Click the arrow to the right of the
<guilabel>Media Size</guilabel> box to see a long list of different
sizes of media. Choose the size that matches the media which you have
loaded into your printer. Once you have made your choice, the drop
down menu will disappear, and your choice will be shown in the
<guilabel>Media Size</guilabel> box. The available paper sizes will
vary depending upon the printer model you have selected.
</para>
<para>
Some printers support arbitrary (within limits!) paper sizes.
These printers will let you select <emphasis>Custom</emphasis>
or <emphasis>Roll</emphasis> paper sizes. When you select such a
printer, one or both of the <guilabel>Dimensions</guilabel> boxes
will let you enter your paper size (in inches or centimetres). The
boxes will not let you enter sizes that your printer cannot handle.
</para>
</sect3>
<sect3><title>Media Type</title>
<para>
The type of media onto which your image will be printed should be
selected here. Click on the arrow to the right of the <guilabel>Media
Type</guilabel> box to see a long list of the different types of media
onto which you may print your image. Media types include such things
as plain paper, postcards, photo quality paper, transparencies, and
more! Once you have made your choice, the drop down menu will
disappear, and your choice will be shown in the <guilabel>Media
Type</guilabel> box. The choices available will vary depending upon
the printer model you have selected.
</para>
</sect3>
<sect3><title>Media Source</title>
<para>
The <guilabel>Media Source</guilabel> box allows the user to
choose the paper source, sometimes called <emphasis>Input
Slot</emphasis>, that the paper will be fed from. Many printers
only have one available input source (such as the standard paper
tray), in which case this entry will be grayed out. If your printer
does support multiple input sources, you may specify the source of
your choice here. Some Epson printers offer a roll feed option in
addition to the standard paper tray, and many HP LaserJet printers
have multiple paper trays.
</para>
</sect3>
<sect3><title>Ink Type</title>
<para>
Some printers offer a choice of different types of ink or ink
cartridges. Many Canon and Lexmark printers support various
combinations of cartridges, such as black only, black and color,
photo color, and so forth. Most Epson printers let you choose
between three and four color printing (three color uses only color
ink, while four color uses black ink as well). Epson printers that
support six color photo printing allow you to choose five and six
color printing as well.
</para>
</sect3>
<sect3><title>Resolution</title>
<para>
Click on the arrow to the right of the
<guilabel>Resolution</guilabel> box to see a long list of resolutions
at which you can print your image. The list is written with the
lowest resolution at the top, with increasing resolution (and
generally improved printing quality) as you approach the bottom of the
list. Different printers support different resolution options, and
many printers support different quality choices using the same basic
resolution. In this menu are a few terms which may be unfamiliar to
you, and they will now be explained.
</para>
<sect4><title>DPI</title>
<para>
DPI is an acronym which stands for <emphasis>D</emphasis>ots
<emphasis>P</emphasis>er <emphasis>I</emphasis>nch. This term refers
to the number of dots that your printer will print in a space of one
inch (approximately 2.54 cm). This is highly dependent upon the
capability of your printer. Resolutions below 300 DPI are
used for draft quality. For general purpose printing, select
300 - 360 DPI. Higher quality printing can be achieved by
selecting 600 - 720 DPI. Settings higher than this are used for the
highest possible quality for printing photographs and other high
quality graphics. Experiment with your printer and these settings
with different types of graphics and photographs to see what
results you can obtain with your printer. High resolutions (large
numbers of dots per inch) require substantial image processing time,
and the print files can be very large; it's not uncommon for a full
page, 1440x720 DPI image to require 100 MB of temporary storage!
</para>
</sect4>
<sect4><title>Draft or Fast Economy Draft</title>
<para>
When this text appears next to the resolution, it refers to the
fact that the quality will be relatively low, but suitable for rough
drafts. Draft quality is higher than fast economy draft. These
options will give you the fastest printing speed. Economy Draft uses
less ink, and as a result the image will be pale. These modes are
generally not very useful for printing photographs.
</para>
</sect4>
<sect4><title>Unidirectional</title>
<para>
When printing an image, you have probably noticed the print
head inside the printer moving back and forth across the print media.
Many printers are capable of putting ink on the page regardless of
which direction the print head is moving. However, quality can
sometimes be improved by only putting ink on the page when the printer
head is moving in one direction. The
<guimenuitem>Unidirectional</guimenuitem> setting instructs the
software to only place ink on the page when the print head is moving
one way. When the print head returns, it will not place ink on the
page. On many printers, the print quality is better, at the expense
of printing speed.
</para>
</sect4>
<sect4><title>High(est) Quality</title>
<para>
With lower quality print modes, one may see an effect where
the printed image looks like it has rows of stripes with a small
separation between the stripes. This effect is called "banding" and
is undesirable. In the <emphasis>high</emphasis> and
<emphasis>highest</emphasis> quality modes, the printer will make more
passes over the same part of the page in order to improve quality and
(reduce or) eliminate banding. This requires more temporary disk
space and prints more slowly, but does not require significantly more
processing time.
</para>
</sect4>
<sect4><title>Microweave</title>
<para>
Certain Epson printers (older models mostly) support a printing
mode called <emphasis>Microweave</emphasis>. This mode uses
special software within the printer to improve the print quality.
Microweave print modes will usually produce better quality
output than non-Microweave modes, with only a small performance
penalty. If Microweave is not listed at your chosen
resolution, fear not. In those cases, the non-Microweave print
modes offer similar printing quality improvements.
</para>
</sect4>
<sect4><title>DMT</title>
<para>
DMT is an acronym which stands for <emphasis>D</emphasis>ot
<emphasis>M</emphasis>odulation
<emphasis>T</emphasis>echnology.
This term refers to a print mode used by certain Canon printers
to improve the quality of the printed output. Unfortunately,
at this time, all of the available DMT modes do not work
correctly. The cases which do work correctly will offer
significantly improved printing quality.
</para>
</sect4>
</sect3>
</sect2>
<sect2><title id="sec-preview">Preview</title>
<para>
Notice in the upper left of the window is a preview of your image.
This preview is a representation of where your picture will print on
the selected media, and approximately what it will look like. This
preview will be updated as you modify selections in the
<guilabel>Position</guilabel>, <guilabel>Size</guilabel>,
<guilabel>Media Size</guilabel>, and <guilabel>Output Type</guilabel>
portions of the window. You may also select the image with your mouse
and move it manually if you wish. In doing so, you will note that the
<guilabel>Position</guilabel> settings are updated accordingly. Take
note of the arrow, which points toward the top of the media, where top
is the first part of the media to enter the printer.
</para>
<para>
The preview may be moved around the page as follows:
</para>
<itemizedlist>
<listitem><para> Clicking and dragging the <emphasis>left</emphasis>
(primary) mouse button moves the image around the page as you would
expect; the image moves with the mouse. </para></listitem>
<listitem><para> Clicking and dragging the
<emphasis>middle</emphasis> mouse button moves the image around the
page in a finer fashion, such that each pixel of mouse movement
moves the image by one point (1/72 inch). This allows very fine
placement of the image on the page. </para></listitem>
<listitem><para> Clicking and dragging the
<emphasis>right</emphasis> (secondary) mouse button moves the image
around the page much the same as with the left button, but the image
will only move in units of the image size. Thus, if the image is
one inch wide and two inches tall, the image will not move at all
until you have moved the mouse far enough so that the image would be
moved one inch vertically and two inches horizontally. This is
handy if you wish to print multiple images of the same size on one
piece of paper.</para></listitem>
<listitem><para> If you hold down the <emphasis>shift</emphasis> key
on the keyboard when you click and drag the mouse, the image will
only move in the horizontal or vertical direction (depending upon
which way you first move the mouse). This allows you to constrain
motion to the horizontal or vertical. </para></listitem>
<listitem><para> If you click another button while dragging the
mouse, the image will immediately return to the position it was in
before you clicked the mouse the first time. This allows you to
not move the image if you have started moving it and have decided
that you don't want to move it. The preview will not respond to the
mouse until you release all of the mouse buttons and click and drag
afresh. </para></listitem>
</itemizedlist>
</sect2>
<sect2><title id="sec-position">Position</title>
<sect3><title>Orientation</title>
<para>
The Orientation menu allows the user to choose the orientation
of the paper. The menu selections are
<guimenuitem>Auto</guimenuitem>, <guimenuitem>Portrait</guimenuitem>,
<guimenuitem>Landscape</guimenuitem>, <guimenuitem>Upside
down</guimenuitem>, and <guimenuitem>Seascape</guimenuitem>. Click on
the rectangular tab to see these choices
and make your selection. When you have done so, the pulldown menu
will have disappeared, and your choice will appear. Also, note that
the preview image will have changed accordingly.
</para>
<para>
When set to <guimenuitem>Auto</guimenuitem>, the software will make an
intelligent choice of orientation based on the dimensions of the image
to be printed. <guimenuitem>Portrait</guimenuitem> orients the print media
with the longest edge going from top to bottom, while
<guimenuitem>Landscape</guimenuitem> orients the paper with the longest edge
going from side to side. <guimenuitem>Upside down</guimenuitem> and
<guimenuitem>Seascape</guimenuitem> orient the paper the same as
<guimenuitem>Portrait</guimenuitem> and <guimenuitem>Landscape</guimenuitem>
respectively, with the difference being that the image is rotated 180 degrees.
</para>
</sect3>
<sect3><title>Automatic Centering</title>
<para>
There are three buttons that deal with centering an image. The
leftmost button is the <guibutton>Vertically</guibutton> button, the
middle button is the <guibutton>Both</guibutton> button, and
the rightmost button is the <guibutton>Horizontally</guibutton>
button. Use the <guibutton>Both</guibutton> button to center your
image both horizontally and vertically. This will cause the top and
bottom borders to be equal, and the left and right borders to be
equal. If you have placed your image manually by using the mouse
button, then you may center the image in the horizontal direction only
by clicking on the <guibutton>Horizontally</guibutton> button.
Likewise, to adjust the image only in the vertical direction, click on
the <guibutton>Vertically</guibutton> button. Note that in
each case, the image is centered with regard to the edges of the
media, and without regard to the printable portion of the media. Many
printers are incapable of printing to each edge of the media. Some
media may have edges which detach. Consult your printer documentation
for more details regarding your printer's capabilities in this regard.
</para>
</sect3>
<sect3><title>Manual Settings</title>
<para>
You will notice that there are six boxes that contain numbers
just below the Orientation menu and just above the GUI buttons related
to centering an image. When you move the preview image manually with
the mouse, or when you click on one of the centering buttons, the
preview image moves and these six boxes get updated.
</para>
<sect4><title>Left</title>
<para>
The number appearing in the <guimenuitem>Left</guimenuitem> box denotes
the number of units (cm or inches) that the left side of the image
will be printed away from the left edge of the media. You may select
the units by clicking the <guibutton>Inch</guibutton> or
<guibutton>cm</guibutton> buttons in the <guilabel>Units</guilabel> section just below
these GUI boxes.
</para>
</sect4>
<sect4><title>Right</title>
<para>
The number appearing in the <guimenuitem>Right</guimenuitem> box denotes
the number of units (cm or inches) that the right side of the image
will be printed away from the left edge of the media. You may select
the units by clicking the <guibutton>Inch</guibutton> or
<guibutton>cm</guibutton> buttons in the <guilabel>Units</guilabel> section just below
these GUI boxes.
</para>
</sect4>
<sect4><title>Right Border</title>
<para>
The number appearing in the <guimenuitem>Right Border</guimenuitem> box denotes
the number of units (cm or inches) that the right side of the image
will be printed away from the right edge of the media. You may select
the units by clicking the <guibutton>Inch</guibutton> or
<guibutton>cm</guibutton> buttons in the <guilabel>Units</guilabel> section just below
these GUI boxes.
</para>
</sect4>
<sect4><title>Top</title>
<para>
The number appearing in the <guimenuitem>Top</guimenuitem> box denotes
the number of units (cm or inches) that the top side of the image
will be printed away from the top edge of the media. You may select
the units by clicking the <guibutton>Inch</guibutton> or
<guibutton>cm</guibutton> buttons in the <guilabel>Units</guilabel> section just below
these GUI boxes.
</para>
</sect4>
<sect4><title>Bottom</title>
<para>
The number appearing in the <guimenuitem>Bottom</guimenuitem> box denotes
the number of units (cm or inches) that the bottom side of the image
will be printed away from the top edge of the media. You may select
the units by clicking the <guibutton>Inch</guibutton> or
<guibutton>cm</guibutton> buttons in the <guilabel>Units</guilabel> section just below
these GUI boxes.
</para>
</sect4>
<sect4><title>Bottom Border</title>
<para>
The number appearing in the <guimenuitem>Bottom Border</guimenuitem> box denotes
the number of units (cm or inches) that the bottom side of the image
will be printed away from the bottom edge of the media. You may select
the units by clicking the <guibutton>Inch</guibutton> or
<guibutton>cm</guibutton> buttons in the <guilabel>Units</guilabel> section just below
these GUI boxes.
</para>
</sect4>
</sect3>
</sect2>
<sect2><title id="sec-scaling">Size</title>
<sect3><title>Slider Bar and Spin Box</title>
<para>
The slider bar can be moved as desired by the user. Notice
that while sliding this bar, the preview image changes accordingly.
One will also note that several boxes in the Gimp-Print GUI change values when this bar is moved.
These boxes are the six position boxes (left, right, right border,
top, bottom, bottom border), the two size boxes (width and height),
and the spin box to the right of the slider bar.
</para>
<para>
This slider bar is used to scale the image to a desirable size, but the same effect can
be obtained by either clicking an arrow on the spin box to the right of this
slider bar, or by manually typing a number into this spin box. Notice
that by setting the spin box in this way, the slider bar is also
moved. All of the described methods will cause the image to be
scaled accordingly.
</para>
</sect3>
<sect3><title>Scale by Percent or PPI</title>
<para>
One may choose to scale the image by a percentage, or by PPI,
which means "<emphasis>p</emphasis>ixels <emphasis>p</emphasis>er
<emphasis>i</emphasis>nch". Click the radio button
next to the word to set the desired scaling factor.
</para>
<para>
When scaling by a percentage, the number reflected in the spin
box next to the slider bar represents the percentage relative
to the full size of the selected print medium. For example, with this spin box
set to 50, the image will be scaled to 50% of the size of the print
medium. When set to 100, the image will attempt to fill the print
medium, within the constraints of maintaining the proper aspect ratio
and the margins of the selected print medium. This effect can be seen
in the preview window.
</para>
<para>
When scaling by PPI, the number reflected in the spin box next to
the slider bar represents the number of pixels that will be
printed per inch. For example, if the user is printing a 640x480
image at a size of 6.4x4.8 inches (as measured by the size boxes), the
image will be printed at 100 DPI.
</para>
</sect3>
<sect3><title>Use Original Image Size</title>
<para>
By clicking this button, the image will be scaled to as close
to the native size of the image as possible. This effect can
immediately be seen in the preview image.
</para>
<para>
The native image size may be found or set in the GIMP by
selecting <guimenuitem>Image/Scale Image</guimenuitem> in the
GIMP. Under the <guilabel>Print Size and Display Unit</guilabel>
group in the <guilabel>Scale Image</guilabel> dialog, you can
determine (or change) the width and height of the image, or
choose the resolution.
</para>
</sect3>
<sect3><title>Width and Height</title>
<para>
These boxes show the size of the printed image in either inches
or centimeters (depending on which unit is selected). The user may
choose to manually modify these values. When one value is modified,
the other value is automatically modified in order to maintain the
aspect ratio (the ratio of width to height). This effect can be
immediately seen in the preview image.
</para>
</sect3>
<sect3><title>Units</title>
<para>
The units can be set to inches or centimeters by clicking the appropriate
radio button next to the desired unit. This setting effects the
values printed in the six position boxes (left, right, right border,
top, bottom, bottom border) and the two size boxes (width and height).
</para>
</sect3>
</sect2>
<sect2><title id="sec-image-settings">Image/Output Settings</title>
<para>
By clicking on the tab labeled <guilabel>Image/Output
Settings</guilabel>, the Gimp-Print window will appear as shown in
<xref linkend="fig-gimp-print-gui-1">. Notice that there are
two sections to this portion of the window, namely,
<guilabel>Image Type</guilabel> and
<guilabel>Output Type</guilabel>.
</para>
<sect3><title>Image Type</title>
<sect4><title>Line Art</title>
<para>
This setting tells the printer driver to generate color
quickly. The color is bold and bright, but color accuracy is not very
good. There may also be some unexpectedly sharp transitions in
colors. This mode is acceptable for printing text with small amounts
of color, and may be acceptable for presentation graphics.
</para>
</sect4>
<sect4><title>Solid Colors</title>
<para>
This mode produces color which is considerably more accurate
than the <guilabel>Line Art</guilabel> mode, but with a reduction in performance. In
general, hues will be accurate but tonalities may not be accurate.
There should be no sharp transitions in colors. This mode is good for
printing presentation graphics in most cases.
</para>
</sect4>
<sect4><title>Photograph</title>
<para>
This mode produces the most accurate colors and tonalities at a
greater cost in performance. This is the mode to use when printing
high quality photographs or other high quality images.
</para>
</sect4>
</sect3>
<sect3><title>Output Type</title>
<para>
The user is given the choice of color, black and white, and
grayscale. Color is selected when the desired output is to be in
color. Greyscale will result in the printed image having various
shades of grey. Black and white is just that. The effect of this
setting can be seen in the preview window.
</para>
</sect3>
<sect3><title>Adjust Output</title>
<para>
Clicking on this button causes the <guilabel>Print Color Adjust</guilabel> window to
appear (see <xref linkend="fig-gimp-print-color-adjust">). In
this window, one will see a representation of the image to be printed
as well as several slider bars. These slider bars collectively adjust
many different aspects of the image. The values can also be adjusted
by clicking the arrows or by typing a value into the appropriate spin
box on the right side of each slider bar.
</para>
<figure id="fig-gimp-print-color-adjust"><title>The Print Color Adjust Window</title>
<mediaobject>
<imageobject>
<imagedata scale="50" fileref="figures/gimp-print-print-color-adjust.png" FORMAT="PNG">
</imageobject>
<textobject>
<phrase>>The Print Color Adjust Window</phrase>
</textobject>
</mediaobject>
</figure>
<sect4><title>Brightness</title>
<para>
Adjust the brightness of the image. A setting of 0.0 gives a fully black
image, while a 2.0 setting gives a fully white image. Values greater than 1.0 will result in
black not being solid and highlights turning white; values less than
1.0 will result in white not being perfectly clear and shadows turning
black.
</para>
</sect4>
<sect4><title>Contrast</title>
<para>
Adjust the contrast of the image. A setting of 0.0 gives a solid gray for the
entire image, the exact gray depending upon the brightness chosen.
</para>
</sect4>
<sect4><title>Cyan, Magenta, Yellow</title>
<para>
These three options allow specification of the cyan, magenta, and
yellow levels independently, for rebalancing the levels. Normally,
these should be adjusted to yield neutral gray, but they can be used
for other effects.
</para>
</sect4>
<sect4><title>Saturation</title>
<para>
Adjust the brilliance of colors. A setting of 0.0 results in pure grayscale.
A saturation setting of less than 1.0 results in more muted colors. A
saturation setting of greater than 1.0 results in more vibrant colors. Very high
saturation often results in very strange effects, including
posterization and banding that might not be expected. For normal
purposes, the saturation should generally be set to a value less than 1.5.
</para>
</sect4>
<sect4><title>Density</title>
<para>
Adjust the amount of ink deposited on the paper. If you have chosen the
correct paper type and are getting ink bleeding through the paper
or puddling, try reducing the density to the lowest value you
can while still achieving solid black. If black is not solid
black, even with the contrast and brightness at 1.0, try increasing
the density. Note that changes to this setting will not be visible in
the image preview.
</para>
<para>
All of the supported printers actually need less than 100% ink
density in most cases, so the actual density is something other than
the nominal density setting. The effective density setting cannot go
above 100%, so if a value specified will result in an excessively high
density level, it will be silently limited to a setting of 1.0.
</para>
</sect4>
<sect4><title>Gamma</title>
<para>
Adjust the gamma of the image, over and above the printer-specific
correction. Gamma less than 1.0 will result in a darker image; gamma
greater than 1.0 will result in a lighter image. Unlike brightness,
gamma adjustment does not change the endpoints; it merely changes the
shape of the input->output curve.
</para>
</sect4>
<sect4><title>Dither Algorithm</title>
<para>
The recommended dither algorithm is <guimenuitem>Adaptive
Hybrid</guimenuitem> (which is the default) for text or other fine
black detail, or if this is mixed with continuous tone images. The
<guimenuitem>Ordered</guimenuitem> dithering algorithm is just as good
(and somewhat faster) for pure continuous-tone images and photographs,
but may yield poor results with text or other fine detail,
particularly at high printing resolutions.
</para>
<para> The <guimenuitem>Fast</guimenuitem> algorithm gives the
fastest results at the expense of color accuracy. It is a simplified
ordered dither. On simple four color printers (or other printers used
in four color mode), the quality is similar to
<guimenuitem>Ordered</guimenuitem>, although dark gray rendition is
not as good due to a simpler transfer between black and colored ink.
With six-color printers, color rendition is somewhat worse, but it
should be quite usable in cases where optimum quality is not critical.
In black and white, it is an efficient way to render grayscale, but it
may not give best results when used with variable dot size printers
(modern Epson printers, or Canon printers using DMT). On rare three
color printers (CMY only) the results should be identical to ordered
dither.
</para>
<para> <guimenuitem>Very Fast</guimenuitem> is even faster than
<guimenuitem>Fast</guimenuitem>, with even more loss of quality.
Color and grayscale output will show strong patterning that resembles
screening, although it isn't. On laser printers, and possibly on
certain kinds of text and line art, <guimenuitem>Very
Fast</guimenuitem> dithering may actually yield the best quality.
</para>
<para>
Error diffusion algorithms (<guimenuitem>Hybrid
Floyd-Steinberg</guimenuitem> is such an algorithm) perform very well
at high densities, and are capable of
rendering very fine detail rather well, but they tend to exhibit artifacts in
the form of "waves" or "worms" of dots which results in noticeable
texturing in pale areas. Furthermore, pale areas immediately adjacent
to white take a while to "build up" sufficient error to print at all.
This is sometimes called "tearing" or "waterfalling".
</para>
</sect4>
<sect4><title>Set Defaults and Close</title>
<para>
When the <guibutton>Set Defaults</guibutton> button is clicked,
the slider bar settings will return to their default values. The
dither algorithm setting is uneffected. The <guilabel>Print Color
Adjust</guilabel> window will close when the
<guibutton>Close</guibutton> button is clicked.
</para>
</sect4>
</sect3>
</sect2>
<sect2><title id="sec-printing-and-saving-settings">Printing and Saving Settings</title>
<para>
At the bottom of the Gimp-Print window, there are five buttons labeled
<guibutton>About</guibutton>,
<guibutton>Print and Save Settings</guibutton>,
<guibutton>Save Settings</guibutton>,
<guibutton>Print</guibutton>,
and <guibutton>Cancel</guibutton>. The <guibutton>About</guibutton>
button will show information about the Gimp-Print software, such as
the version number, authors names, project web site, and software
licensing. After clicking on the <guibutton>About</guibutton>, read
the information, and then close the window by pressing the
<guibutton>OK</guibutton> button.
</para>
<para>
The <guibutton>Print and Save Settings</guibutton> button will
save the current settings and then print the desired image. Recall
that these settings are saved in <filename>~/.gimp-1.2/printrc</filename>. The
<guibutton>Save Settings</guibutton> button will only save the
settings. The <guibutton>Print</guibutton> button will print the
image only. The <guibutton>Cancel</guibutton> will close the
Gimp-Print GUI window.
</para>
</sect2>
</sect1>
</chapter>