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<h2><b>spectro/dispread</b> </h2>
<h3>Summary</h3>
Display test patches on a monitor, read the colorimetric value
result with the colorimeter, and create the chart readings file. The
type of instrument is determined by the communication port selected.
Emission and display measurement instruments are supported.<br>
<br>
If you want to read a display manually rather than automatically,
see <a href="chartread.html">chartread</a> and the <a
href="chartread.html#d">-d</a> option.<br>
<h3>Usage</h3>
<small style="font-family: monospace;">dispread [-options]<i>
inoutfile</i><br>
<a href="#v">-v</a>
Verbose mode<br>
</small><font size="-1"><a style="font-family: monospace;"
href="#display">-display displayname</a><span
style="font-family: monospace;"> [X11 only] Choose X11 display
name<br>
</span></font><font size="-1"><span style="font-family:
monospace;"> <a href="#dnm">-d n[,m]</a>
[X11 only]Choose the display from the following list (default
1),<br>
and
optionally
choose
a
different
display
m
for VideoLUT access.</span></font><br>
<font size="-1"><span style="font-family: monospace;"> <a
href="#d">-d n</a>
Choose
the
display
from
the
following
list
(default 1)</span></font><small style="font-family: monospace;"><br>
</small><span style="font-family: monospace;"> <a href="#dweb">-dweb[:port]</a>
Display via a web server at port (default 8080)</span><br>
<small style="font-family: monospace;"> <span style="font-family:
monospace;"> </span><a style="font-family: monospace;"
href="#c">-c listno</a><span style="font-family: monospace;">
Set
communication port from the following list (default 1)<br>
</span></small><font size="-1"><span style="font-family:
monospace;"> <a href="#p">-p</a>
Use projector mode (if available)</span></font><br>
<font size="-1"><span style="font-family: monospace;"><a
href="#y">-y X</a>
Display
type - instrument specific list to choose from.</span></font><br>
<small style="font-family: monospace;"> <span
style="text-decoration: underline;">-</span><a href="#k">k
file.cal</a>
Load calibration file into display while reading<br>
</small><small style="font-family: monospace;"> <span
style="text-decoration: underline;">-</span><a href="#K">K
file.cal</a>
Apply
calibration file to test values while reading</small><br>
<small style="font-family: monospace;"> <a href="#s">-s</a>
Save spectral information (default don't
save)<br>
</small><font style="font-family: monospace;" size="-1"> <a
href="#P">-P ho,vo,ss</a>
Position test window and scale it<br>
ho,vi:
0.0
=
left/top,
0.5
=
center,
1.0 = right/bottom etc.<br>
ss:
0.5
=
half,
1.0
=
normal,
2.0 = double etc.<br>
</font><font size="-1"><span style="font-family: monospace;"><a
href="#F">-F</a>
Fill whole screen with black background</span></font><br
style="font-family: monospace;">
<small style="font-family: monospace;"> <span
style="text-decoration: underline;"></span><a href="#n">-n</a>
[X11
only]
Don't
set
override
redirect
on test window<br>
</small><small style="font-family: monospace;"> <a href="#J">-J</a>
Run calibration first</small><br>
<font size="-1"><span style="font-family: monospace;"> <a
href="#N">-N</a>
Disable auto calibration of instrument<br>
</span></font><font size="-1"><span style="font-family:
monospace;"> </span><a style="font-family: monospace;"
href="#H">-H</a><span style="font-family: monospace;">
Use high resolution spectrum mode (if
available)<br>
</span></font><font size="-1"><span style="font-family:
monospace;"> </span><a style="font-family: monospace;"
href="#V">-V</a><span style="font-family: monospace;">
Use adaptive measurement mode (if
available)<br>
<a href="#w">-w</a>
Disable
normalisation
of
white
to
Y
=
100</span></font><small><span style="font-family: monospace;"></span></small><br>
<font size="-1"><span style="font-family: monospace;"><a
href="#X1">-X file.ccmx</a>
Apply Colorimeter Correction Matrix</span></font><br>
<span style="font-family: monospace;"> <a href="#X2">-X
file.ccss</a>
Use
Colorimeter
Calibration
Spectral Samples for calibration</span><br style="font-family:
monospace;">
<span style="font-family: monospace;"> <a href="#X3">-X N</a>
0:
Technology
(Display
description)</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
1: etc.</span><font size="-1"><span style="font-family:
monospace;"><br>
</span></font><small><span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#Q">-Q <i>observ</i></a><span
style="font-family: monospace;">
Choose CIE Observer for spectrometer or CCSS
colorimeter data:</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
1931_2 </span></small><small><span
style="font-family: monospace;">(def.)</span></small><small><span
style="font-family: monospace;">, 1964_10, S&B 1955_2, shaw,
J&V 1978_2, 1964_10c</span></small><br>
<small><span style="font-family: monospace;"> <a
href="dispread.html#I">-I b|w</a>
Drift
compensation,
Black:
-Ib,
White:
-Iw,
Both:
-Ibw</span></small><br>
<font size="-1"><span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#C">-C "command"</a><span
style="font-family: monospace;">
Invoke shell
"command" each time a color is set<br>
</span></font><font size="-1"><span style="font-family:
monospace;"> </span><a style="font-family: monospace;"
href="#M">-M "command"</a><span style="font-family: monospace;">
Invoke shell
"command" each time a color is measured</span></font><br>
<font size="-1"><span style="font-family: monospace;"> <a
href="#W">-W n|h|x</a>
Override
serial
port
flow
control:
n
=
none, h = HW, x = Xon/Xoff</span></font><br>
<small style="font-family: monospace;"> <a href="#D">-D [level]</a>
Print debug
diagnostics to stderr</small><br>
<small style="font-family: monospace;"> <a href="#p1"><i>inoutfile</i></a>
Base name for input[<a href="File_Formats.html#.ti1">.ti1</a>]/output[<a
href="File_Formats.html#.ti3">.ti3</a>] file.<br>
</small> <br>
<b>Examples</b><br>
<br>
dispread -c1 -i92 mycrt<br>
<h3>Comments<br>
</h3>
This is the tool for exercising a display, in order to measure its
color characteristics. The device test colors are defined by the
outfile.ti1 file, while the resulting device+colorimetric and
optional spectral readings are stored in the outfile.ti3 file.
Display calibration curves can be applied during the measurements,
and the curves included in the resulting .ti3 data file using the <span
style="font-weight: bold;">-k</span>flag. See <a
href="dispcal.html">dispcal</a> for information on how to
calibrate the display before profiling it. For best results, you
should run this against a neutral grey desktop background, and avoid
having any bright images or windows on the screen at the time you
run it.<br>
<br>
<a name="v"></a> The <b>-v</b> flag reports progress information.<br>
<br>
<a name="display"></a><span style="font-weight: bold;">-display</span>:
When running on a UNIX based system that used the X11 Windowing
System, <b>dispread</b> will by default use the $DISPLAY
environment variable to determine which display and screen to read
from. This can be overridden by supplying an X11 display name to the
<span style="font-weight: bold;">-display</span> option. Note that
if Xinerama is active, you can't select the screen using $DISPLAY or
-display, you have to select it using the <span style="font-weight:
bold;">-d</span> parameter.<br>
<br>
<a name="d"></a> <span style="font-weight: bold;">-d</span>: By
default the main display will be the location of the test window. If
the system has more than one display or screen, an alternate
display/screen can be selected with the <span style="font-weight:
bold;">-d</span> parameter. If you invoke <span
style="font-weight: bold;">dispread</span> so as to display the
usage information (i.e. "dispread -?" or "dispread --"), then the
discovered displays/screens will be listed. Multiple displays may
not be listed, if they appear as a single display to the operating
system (ie. the multi-display support is hidden in the video card
driver). On UNIX based system that used the X11 Windowing System,
the <span style="font-weight: bold;">-d</span> parameter will
override the screen specified by the $DISPLAY or <span
style="font-weight: bold;">-display</span> parameter.<br>
<br>
On X11 the inability to access VideoLUTs could be because you are
trying to access a remote display, and the remote display doesn't
support the XF86VidMode extension, or perhaps you are running
multiple monitors using NVidia TwinView, or MergedFB, and trying to
access anything other than the primary monitor. TwinView and
MergedFB don't properly support the XF86VidMode extension for
multiple displays. You can use <a href="dispwin.html#r">dispwin -r</a>
to test whether the VideoLUTs are accessible for a particular
display. See also below, on how to select a different display for
VideoLUT access. Also note that dispcal will fail if the Visual
depth doesn't match the VideoLUT depth. Typically the VideoLUTs have
256 entries per color component, so the Visual generally needs to be
24 bits, 8 bits per color component.<br>
<br>
<a name="dnm"></a>Because of the difficulty cause by TwinView and
MergedFB in X11 based systems, you can optionally specify a separate
display number after the display that is going to be used to present
test patches, for accessing the VideoLUT hardware. This must be
specified as a single string, e.g. <span style="font-weight: bold;">-d
1,2</span> . Some experimentation may be needed using <a
href="dispwin.html">dispwin</a> on such systems, to discover what
screen has access to the VideoLUT hardware, and which screens the
test patches appear on. You may be able to calibrate one screen, and
then share the calibration with another screen. Profiling can be
done independently to calibration.<br>
<br>
<a name="dweb"></a><span style="font-weight: bold;">-dweb</span> or
<span style="font-weight: bold;">-dweb:port</span> starts a
standalone web server on your machine, which then allows a local or
remote web browser to display the the color test patches. By default
port <span style="font-weight: bold;">8080</span> is used, but this
can be overridden by appending a <span style="font-weight: bold;">:</span>
and the port number i.e. <span style="font-weight: bold;">-dweb:8001</span>.
The URL will be <span style="font-weight: bold;">http://</span>
then name of the machine or its I.P. address followed by a colon and
the port number - e.g something like <span style="font-weight:
bold;">http://192.168.0.1:8080</span>. If you use the verbose
option (<span style="font-weight: bold;">-v</span>) then a likely
URL will be printed once the server is started, or you could run <span
style="font-weight: bold;">ipconfig</span> (MSWin) or <span
style="font-weight: bold;">/sbin/ifconfig</span> (Linux or OS X)
and identify an internet address for your machine that way.<br>
<br>
Note that if you use this method of displaying test patches, that
there is no access to the display VideoLUTs and that the colors will
be displayed with 8 bit per component precision, and any
screen-saver or power-saver will not be disabled. You will also be
at the mercy of any color management applied by the web browser, and
may have to carefully review and configure such color management.
See the <a href="dispcal.html#o">-o</a> flag for an explanation of
the implications of having no access to the VideoLUTs.<br>
<br>
<a name="c"></a> <span style="font-weight: bold;">-c</span>: The
instrument is assumed to communicate through a USB or serial
communication port, and the port can be selected with the <b>-c</b>
option, if the instrument is not connected to the first port. If you
invoke <span style="font-weight: bold;">dispread</span> so as to
display the usage information (i.e. "dispread -?" or "dispread --"),
then the discovered USB and serial ports will be listed. On
UNIX/Linux, a list of all possible serial ports are shown, but not
all of them may actually be present on your system.<br>
<br>
<a name="p"></a>The <span style="font-weight: bold;">-p</span> flag
allows measuring in projector mode, using instruments that support
this.<br>
<br>
<a name="y"></a>The <span style="font-weight: bold;">-y</span> flag
allows setting the Display Type. Most colorimeters need this
parameter set to operate correctly. The selection typically
determines two aspects of of the instrument operation: <span
style="font-weight: bold;">1)</span> It may set the measuring mode
to suite <a
href="http://en.wikipedia.org/wiki/Comparison_of_display_technology"><span
style="font-weight: bold;">refresh</span> or <span
style="font-weight: bold;">non-refresh</span> displays</a>.
Typically only LCD (Liquid Crystal) displays have a non-refresh
nature. <span style="font-weight: bold;">2)</span> It may select an
instrument calibration matrix suitable for a particular display
type. The selections available depends on the type and model of
instrument, and a list of the options for the discovered instruments
will be shown in the <a href="ArgyllDoc.html#CmdLine">usage</a>
information. For more details on what particular instruments support
and how this works, see <a href="instruments.html">Operation of
particular instruments</a>.<br>
<br>
<a name="s"></a><span style="font-weight: bold;">-s</span>: By
default only the colorimetric information (XYZ value) will be saved,
but for instruments that support spectral readings (such as the
Gretag Spectrolino), the <b>-s</b> option will save the spectral
readings to the .ti3 file as well.<br>
<br>
<a name="k"></a> <span style="font-weight: bold;">-k: </span>If a
display video lookup table calibration <a
href="File_Formats.html#.cal">.cal</a> file is provided, it will
be loaded into the display <span style="font-weight: bold;">ViedoLUTs</span>
while the measurements are being taken, thereby being applied to the
measurement values, and the calibration will also included in the
resulting .ti3 data file, so that <a href="colprof.html">colprof</a>
can include it as a <span style="font-weight: bold;">vcgt</span>
tag in the resulting profile. This is the <span style="font-weight:
bold;">normal</span> way to profile a calibrated display. The
calibration file has usually been created using <a
href="dispcal.html">dispcal</a>. If a calibration file is not
created, then the display will be read in whatever calibration state
it is in. If the calibration file indicates that the displays
VideoLUTs are not accessible, or if they prove not to be accessible,
then dispread will switch to <span style="font-weight: bold;">-K</span>
mode (see below). <span style="font-weight: bold;">NOTE</span> that
the calibration is loaded into the display hardware just before the
instrument starts measurement, after the test window first appears.<br>
<br>
<a name="K"></a> <span style="font-weight: bold;">-K: </span>If a
display video lookup table calibration <a
href="File_Formats.html#.cal">.cal</a> file is provided, it will
be applied to the test values for each measurement, and also
included in the resulting .ti3 data file, so that <a
href="colprof.html">colprof</a> can include it as a <span
style="font-weight: bold;">vcgt</span> tag in the resulting
profile. This is <span style="font-weight: bold;">NOT</span>
normally the best way to profile a calibrated display, since the
frame buffer may have lower precision than the VideoLUTs output
values.<br>
<br>
<a name="P"></a> The <span style="font-weight: bold;">-P</span>
parameter allows you to position and size the test patch window. By
default it is places in the center of the screen, and sized
appropriately for the type of instrument. The <span
style="font-weight: bold;">ho</span> and <span
style="font-weight: bold;">vo</span> values govern the horizontal
and vertical offset respectively. A value of 0.0 positions the
window to the far left or top of the screen, a value of 0.5
positions it in the center of the screen (the default), and 1.0
positions it to the far right or bottom of the screen. The <span
style="font-weight: bold;">ss</span> parameter is a scale factor
for the test window size. A value of 0.5 for instance, would produce
a half sized window. A value of 2.0 will produce a double size
window. Note that the ho,vo,ss numbers must be specified as a single
string (no space between the numbers and the comma). For example, to
create a double sized test window at the top right of the screen,
use <span style="font-weight: bold;">-P 1,0,2</span> .<br>
<br>
<a name="F"></a> The <span style="font-weight: bold;">-F</span>
flag causes the while screen behind the test window to be masked
with black. This can aid black accuracy when measuring CRT displays
or projectors.<br>
<br>
<a name="n"></a><span style="font-weight: bold;">-n</span>: When
running on a UNIX based system that used the X11 Windowing System, <b>dispread</b>
normally selects the override redirect so that the test window will
appear above any other windows on the display. On some systems this
can interfere with window manager operation, and the <b>-n</b>
option turns this behaviour off.<br>
<br>
<a name="J"></a> The -<span style="font-weight: bold;">J</span>
option runs through the black and sensor relative calibration
routines for the Xrite DTP92 and DTP94 instrument, the black level
calibration for the Eye-One Display 1, and a CRT frequency
calibration for the Eye-One Display 2. For the black calibration the
instrument should be placed on an opaque, black surface, and any
stray light should be avoided by placing something opaque over the
instrument. If a Spectrolino is being used, then a white and black
calibration will always be performed before the instrument can be
placed on the display, unless the <a href="#N">-N</a> flag is used.
Generally it is not necessary to do a calibration every time an
instrument is used, just now and again. There is no point in
doing a CRT frequency calibration, as this will be done
automatically at the commencement of patch reading.<br>
<br>
<a name="N"></a>The <b>-N</b> flag disables any automatic
instrument calibration (used for the Gretag Spectrolino for
instance). This would be used when the instrument is being used for
a series of measurements, and it is inconvenient to place it on it's
calibration tile between measurements. The instrument should be
calibrated at least once for each measurement session though.<br>
<br>
<a name="H"></a> The -<span style="font-weight: bold;">H</span>
option turns on high resolution spectral mode, if the instrument
supports it. See <a href="instruments.html">Operation of particular
instruments</a> for more details. This may give better accuracy
for display measurements.<br>
<br>
<a name="V"></a> The -<span style="font-weight: bold;">V</span>
option uses adaptive emission measurement mode, if the instrument
supports it, such as the Eye-One Pro. This may give better accuracy
for low level measurements, but may be more inconsistent overall due
to the varying integration times. Overall measurement time will
probably be longer.<br>
<br>
<a name="w"></a>The <b>-w</b> flag disables the normalisation of
the white patch value to 100.0, resulting in values that are in
cd/m^2. This is mainly for diagnostic purposes.<br>
<br>
<a name="X1"></a> The -<span style="font-weight: bold;">X <span
style="font-style: italic;">file.ccmx</span></span> option reads
a <a href="File_Formats.html#.ccmx">Colorimeter Correction Matrix</a>
from the given file, and applies it to the colorimeter instruments
readings. This can improve a colorimeters accuracy for a particular
type of display. A list of contributed <span style="font-weight:
bold;">ccmx</span> files is <a href="ccmxs.html">here</a>.<br>
<br>
<a name="X2"></a> The -<span style="font-weight: bold;">X <span
style="font-style: italic;">file.ccss</span></span> option reads
a <a href="File_Formats.html#.ccss">Colorimeter Calibration
Spectral Sample</a> from the given file, and uses it to set the
colorimeter instruments calibration. This will only work with
colorimeters that rely on sensor spectral sensitivity calibration
information (ie. the X-Rite <span style="font-weight: bold;">i1d3</span>,
or the DataColor <span style="font-weight: bold;">Spyder4</span>).This
can
improve
a
colorimeters accuracy for a particular type of display.<br>
<br>
<a name="X3"></a> The -<span style="font-weight: bold;">X <span
style="font-style: italic;">N</span></span> option selects a <a
href="File_Formats.html#.ccss">Colorimeter Calibration Spectral
Sample</a> from the list of installed ccss files, rather than
specifying a specific ccss files as in the above usage. The CCSS
file that came with the i1d3 colorimeters can be installed using <a
href="i1d3ccss.html">i1d3ccss</a>, or one can be created and
installed using <a href="ccxxmake.html">ccxxmake</a>.<br>
<br>
<a name="Q"></a> The <b>-Q</b> flag allows specifying a tristimulus
observer, and is used to compute PCS (Profile Connection Space)
tristimulus values from spectral readings or using a colorimeter
that has CCSS capability. The following choices are available:<br>
<b> 1931_2</b> selects the standard CIE 1931 2 degree
observer. The default.<br>
<b>1964_10</b> selects the standard CIE 1964 10 degree
observer.<br>
<b>1955_2</b> selects the Stiles and Birch 1955 2 degree
observer<br>
<b>1978_2 </b>selects the Judd and Voss 1978 2 degree
observer<br>
<b>shaw</b> selects the Shaw and Fairchild 1997 2 degree
observer<br>
<b>1964_10c</b> selects a version of the CIE 1964 10 degree
observer that has been adjusted using a 3x3 matrix to better agree
with the 1931 2 degree observer.<br>
<br>
<span style="font-weight: bold;">NOTE</span> that if you select
anything other than the default 1931 2 degree observer, that the Y
values will not be cd/m^2, due to the Y curve not being the CIE 1924
photopic V(λ) luminosity function.<br>
<br>
<a name="I"></a> The -<span style="font-weight: bold;">I <span
style="font-style: italic;">b|w</span></span> options invoke
instrument black level, and display white level compensation
(respectively). Instrument black level drift compensation attempts
to combat instrument black calibration drift by using a display
black test patch as a reference. If an instrument is not
acclimatised sufficiently to the measurement conditions, changes in
temperature can affect the black readings. Display white level drift
compensation attempts to combat changes in display brightness as it
warms up by measuring a white patch every so often, and using it to
normalise all the other readings. If just instrument black drift
compensation is needed, use <span style="font-weight: bold;">-Ib</span>.
If just display white level compensation is needed, use <span
style="font-weight: bold;">-Iw</span>. If both are needed, use <span
style="font-weight: bold;">-Ibw</span> or <span
style="font-weight: bold;">-Iwb</span>.<span style="font-weight:
bold;"> <br>
<br>
</span><a name="C"></a> The -<span style="font-weight: bold;">C</span>
<span style="font-weight: bold;">"command" </span>option allows a
method of relaying each test value to some other display than that
on the system running dispread (for instance, a photo frame, PDA
screen etc.), by causing the given command to be invoked to the
shell, with six arguments. The first three arguments are the RGB
test color as integers in the range 0 to 255, the second three
parameters are the RGB test color as floating point numbers in the
range 0.0 to 1.0. The script or tool should relay the given color to
the screen in some manner (e.g. by generating a raster file of the
given color and sending it to the display being profiled), before
returning. Note that a test window will also be created on the
system running dispread.<br>
<br>
<a name="M"></a> The -<span style="font-weight: bold;">M</span> <span
style="font-weight: bold;">"command" </span>option allows a
method of gathering each test value from some external source, such
as an instrument that is not directly supported by Argyll. The given
command is involked to the shell, with six arguments. The first
three arguments are the RGB test color as integers in the range 0 to
255, the second three parameters are the RGB test color as floating
point numbers in the range 0.0 to 1.0. The script or tool should
create a file called <span style="font-weight: bold;">"command.meas</span>"
that contains the XYZ values for the given RGB (or measured from the
test window) in cd/m^2 as three numbers separated by spaces, before
returning. If the command returns a non-zero return value, dispread
will abort. Note that a test window will also be created on the
system running dispread.<br>
<br>
<a name="W"></a>The <b>-W</b> <span style="font-weight: bold;">n|h|x</span>
parameter overrides the default serial communications flow control
setting. The value <span style="font-weight: bold;">n</span> turns
all flow control off, <span style="font-weight: bold;">h</span>
sets hardware handshaking, and <span style="font-weight: bold;">x</span>
sets Xon/Xoff handshaking. This commend may be useful in workaround
serial communications issues with some systems and cables. <br>
<br>
<a name="D"></a>The <b>-D</b> flag causes communications and other
instrument diagnostics to be printed to stdout. A level can be set
between 1 .. 9, that may give progressively more verbose
information, depending on the instrument. This can be useful in
tracking down why an instrument can't connect.<br>
<br>
<a name="p1"></a> The final parameter on the command line is the
base filename for the <a href="File_Formats.html#.ti1">.ti1</a>
input file, and the <a href="File_Formats.html#.ti3">.ti3</a>
output file. <b>dispread</b> will add the .ti1 and .ti3 extensions
automatically.<br>
<br>
<span style="font-weight: bold;">NOTE</span> that on an X11 system,
if the environment variable <span style="font-weight: bold;">ARGYLL_IGNORE_XRANDR1_2</span>
is set (ie. set it to "yes"), then the presence of the XRandR 1.2
extension will be ignored, and other extensions such as Xinerama and
XF86VidMode extension will be used. This may be a way to work around
buggy XRandR 1.2 implementations.<br>
<br>
<hr style="width: 100%; height: 2px;"><br>
If a large number of patches is being read, the screensaver on many
systems can interfere with the operation of dispread. It is
therefore advisable in these cases to manually turn off the
screensaver before commencing the measurements.<br>
<br>
If communications break down with a USB connected instrument, you
may have to unplug it, and plug it in again to recover.<br>
<br>
Some systems (Apple OSX in particular) have a special set of user
interface controls ("Universal Access") that allows altering the
display in ways designed to assist visually impaired users, by
increasing contrast etc. This will interfere badly with any attempts
to calibrate or profile such a system, and must be turned off in
order to do so. Note that certain magic keyboard sequences can turn
this on by accident.<br>
<br>
<br>
<br>
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