<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>colprof</title>
<meta http-equiv="content-type"
content="text/html; charset=ISO-8859-1">
<meta name="author" content="Graeme Gill">
</head>
<body>
<h2> profile/colprof</h2>
<h3>Summary</h3>
Create an <a href="File_Formats.html#ICC">ICC</a> profile from
the <a href="File_Formats.html#.ti3">.ti3</a> test chart patch
values.<br>
<h3>Usage Summary</h3>
<small><span style="font-family: monospace;">colprof [-</span><i
style="font-family: monospace;">options</i><span
style="font-family: monospace;">] outfile</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#v">-v</a><span
style="font-family: monospace;">
Verbose mode</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#A">-A "manufacturer"</a><span
style="font-family: monospace;"> Set the manufacturer
description string</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#M">-M "model"</a><span
style="font-family: monospace;">
Set the model
description string</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#D">-D "description"</a><span
style="font-family: monospace;"> Set the
profile Description string (Default "</span><span
style="font-style: italic; font-family: monospace;">inoutfile</span><span
style="font-family: monospace;">")</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#C">-C "copyright"</a><span
style="font-family: monospace;"> Set the copyright
string</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#q">-q lmhu</a><span
style="font-family: monospace;">
Quality - Low, Medium (def),
High, Ultra</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#b">-b [lmhun]</a><span
style="font-family: monospace;">
Low quality B2A table - or specific B2A quality or none for
input device</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#y">-y</a><span
style="font-family: monospace;">
Verify A2B profile</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#ni">-ni</a><span
style="font-family: monospace;">
Don't
create input (Device) shaper curves<br>
</span></small><small><span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="colprof.html#np">-np</a><span
style="font-family: monospace;">
Don't create input (Device) grid position
curves</span></small><br style="font-family: monospace;">
<small><span style="font-family: monospace;"></span><span
style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#no">-no</a><span
style="font-family: monospace;">
Don't
create output (PCS) shaper curves<br>
</span></small><small><span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="colprof.html#nc">-nc</a><span
style="font-family: monospace;">
Don't put the input .ti3 data in the profile</span></small><br
style="font-family: monospace;">
<small><span style="font-family: monospace;"></span><span
style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#k">-k zhxr</a><span
style="font-family: monospace;">
Black generation: z = zero K,</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
h = 0.5 K (def), x = max K, r = ramp K</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#kp">-k p stle stpo enpo enle
shape</a><br style="font-family: monospace;">
<span style="font-family: monospace;">
stle: K level at White 0.0 -
1.0</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
stpo: start point of
transition Wh 0.0 - Bk 1.0</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
enpo: End point of transition
Wh 0.0 - Bk 1.0</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
enle: K level at Black 0.0 -
1.0</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
shape: 1.0 = straight,
0.0-1.0 concave, 1.0-2.0 convex</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="xicclu.html#K">-K parameters</a><span
style="font-family: monospace;"> Same as
-k, but target is K locus rather than K value itself</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#l">-l <i>tlimit</i></a><span
style="font-family: monospace;">
override CMYK
total ink limit, 0
- 400% (default from .ti3)</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#L">-L <i>klimit</i></a><span
style="font-family: monospace;">
override
black ink limit, 0 - 100% (default from .ti3)</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#a">-a lxgs</a><span
style="font-family: monospace;">
Algorithm type override</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
l = Lab clut (def.), x = XYZ lut</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
g = gamma+matrix, s = shaper+matrix</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
G = single gamma+matrix,
S = single shaper+matrix</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#u">-u</a><span
style="font-family: monospace;">
If
Lut input profile, make it absolute (non-standard)</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#i">-i <i>illum</i></a><span
style="font-family: monospace;">
Choose illuminant
for print/transparency spectral data:</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
A, D50 (def.), D65, F5,
F8, F10 or file.sp</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#o">-o <i>observ</i></a><span
style="font-family: monospace;">
Choose CIE Observer for spectral
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</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#f">-f</a><span
style="font-family: monospace;">
Use
Fluorescent Whitening Agent compensation</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#r">-r avgdev</a><span
style="font-family: monospace;">
Average deviation of device+instrument readings as a
percentage (default 0.5%)</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#s">-s src.icc</a><span
style="font-family: monospace;">
Apply gamut mapping to perceptual B2A table for given source</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#S">-S src.icc</a><span
style="font-family: monospace;">
Apply gamut mapping to perceptual and saturation B2A table<br>
<a href="#nP">-nP</a>
Use colormetric source gamut to make perceptual table<br>
<a href="#nS">-nS</a>
Use colormetric source gamut to make saturation table<br
style="font-family: monospace;">
</span><span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#g">-g src.gam</a><span
style="font-family: monospace;">
Use source
image gamut as well for gamut mapping</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#p">-p aprof.icm</a><span
style="font-family: monospace;">
Incorporate abstract profile into output tables</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#t">-t intent</a><span
style="font-family: monospace;">
Override gamut mapping
intent for perceptual table:</span><br style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#T">-T intent</a><span
style="font-family: monospace;">
Override gamut mapping
intent for saturation table:</span><br style="font-family: monospace;">
<span style="font-family: monospace;"></span></small><small><span
style="font-family: monospace;">
a -
Absolute Colorimetric (in Jab) [ICC
Absolute Colorimetric]<br>
aw - Absolute Colorimetric (in
Jab) with scaling to fit white point<br style="font-family: monospace;">
</span><span style="font-family: monospace;">
aa - Absolute Appearance</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
r - White Point
Matched Appearance [ICC
Relative Colorimetric]</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
la - Luminance matched Appearance</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
p - Perceptual (Preferred)
[ICC Perceptual]</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
ms - Saturation</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
s - Enhanced Saturation [ICC
Saturation]</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
al - Absolute Colorimetric (Lab)</span></small><small><span
style="font-family: monospace;"></span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#c">-c viewcond</a><span
style="font-family: monospace;">
set input viewing conditions for CIECAM02 gamut mapping,</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
either an enumerated choice, or a parameter</span><br
style="font-family: monospace;">
<span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#d">-d viewcond</a><span
style="font-family: monospace;">
set output viewing conditions for CIECAM02, gamut mapping</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
either an enumerated choice, or a parameter:value change</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
Also sets out of gamut clipping CAM space.</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
Enumerated Viewing Conditions:</span><br style="font-family: monospace;">
<span style="font-family: monospace;"></span></small><small><span
style="font-family: monospace;">
pp - Practical Reflection Print</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
pe - Print evaluation environment</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
mt - Monitor in typical work environment</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
mb - Monitor in bright work environment</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
md - Monitor in darkened work
environment</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
jm - Projector in dim environment</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
jd - Projector in dark environment</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
pcd - Photo CD - original scene
outdoors</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
ob - Original scene - Bright Outdoors</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
cx - Cut Sheet Transparencies on a viewing
box</span></small><small><span style="font-family: monospace;"></span><span
style="font-family: monospace;"></span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
s:surround a =
average, m = dim, d = dark,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
c = transparency (default average)</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
w:X:Y:Z Adapted white point
as XYZ (default media white)</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
w:x:y Adapted white
point as x, y</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
a:adaptation Adaptatation
luminance in
cd.m^2
(default 50.0)</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
b:background
Background % of image luminance (default 20)</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
f:flare Flare
light % of image luminance (default 1)</span><br
style="font-family: monospace;">
<span style="font-family: monospace;">
f:X:Y:Z Flare color
as XYZ (default media white)</span><br style="font-family: monospace;">
<span style="font-family: monospace;">
f:x:y Flare color as x,
y<br>
<a href="#P">-P</a>
Create gamut gammap_p.wrl and gammap_s.wrl diagostics<br
style="font-family: monospace;">
</span><span style="font-family: monospace;"> </span><a
style="font-family: monospace;" href="#p1"><i>inoutfile</i></a><span
style="font-family: monospace;">
Base name for input.ti3/output.icc file</span></small><br>
<h3>Options<br>
</h3>
<b><a name="v"></a>-v</b> Turn on verbose mode. Gives progress
information as the profile is created. Since colprof can take a long
time to generate, this is often useful to monitor progress. If used in
combination with the <b>-y</b> flag, the error of each test point to
the resulting profile will be printed out.<br>
<br>
<a name="A"></a>The <b>-A</b> parameter allows setting of the device
manufacturer description tag. The parameter should be a string that
identifies the manufacturer of the device being profiled. With most
command line shells, it will be necessary to enclose the parameter
with double quotes, so that spaces and other special characters are
included in the parameter, and not mistaken for the start of another
flag, or as a final command line parameters. By default no manufacturer
description string tag will be generated for the profile.<br>
<br>
<a name="M"></a>The <b>-M</b> parameter allows setting of the device
mode description tag. The parameter should be a string that identifies
the particular model of device being profiled. With most command line
shells, it will be necessary to enclose the parameter with double
quotes, so that spaces and other special characters are included in the
parameter, and not mistaken for the start of another flag, or as a
final command line parameters. By default no model description string
tag will be generated for the profile.<br>
<br>
<a name="D"></a>The <b>-D</b> parameter allows setting of the profile
description tag. The parameter should be a string that describes the
device and profile. On many systems, it will be this string that will
be used to identify the profile from a list of possible profiles. With
most command line shells, it will be
necessary to enclose the parameter with double quotes, so that spaces
and other special characters are included in the parameter, and not
mistaken for the start of another flag, or as a final command line
parameter. Many programs that deal with ICC profiles use the
description tag to identify a profile, rather than the profile
filename, so using a descriptive string is important in being able to
find a profile. By default, the base name of the resulting profile will
be used as the description.<br>
<br>
<a name="C"></a>The <b>-C</b> parameter allows setting of the profile
copyright tag. The parameter should be a string that describes the
copyright (if any) claimed on the profile being generated.. With most
command line shells, it will be necessary to enclose the parameter
with double quotes, so that spaces and other special characters are
included in the parameter, and not mistaken for the start of another
flag, or as a final command line parameters. By default a generic
copyright string will be generated for the profile.<br>
<br>
<a name="q"></a> The <b>-q</b> parameter sets the level of
effort and/or detail in the resulting profile. For table based profiles
("lut" profiles), it sets the main lookup table size, and hence
quality in the resulting profile. It is highly recommended that <span
style="font-weight: bold;">-qm</span> be used as a starting point, and
other settings only tried after this has been evaluated. <span
style="font-weight: bold;">-qu</span> should almost never be used,
except to prove that it should almost never be used.<br>
<br>
<a name="b"></a> The <b>-b</b> flag overrides the <b>-q</b>
parameter, and sets the lut resolution for the BtoA (inverse) to a low
value. The creation of the B2A table is fairly time consuming, and if
the profile is only going to be used by <a href="targen.html">targen</a>,
or if it will only be used as an input space profile, or if it will
only
be linked as an output profile using Argyll's <a
href="collink.html"> collink</a> utility using the <b>-G</b> option
(inverse AtoB option), then a high quality BtoA table is not required,
and some time and profile space can be saved. If the profile is to be
used
as an output space profile with another CMS, or is going to be linked
using
the simple (-s) or mapping mode (-g) options, then the -b flag should
NOT
be set. Optionaly, a specific B2A table quality can be set.<br>
<br>
For input devices, the presence of a B2A table is not mandatory,
and it can be omitted entirely from the profile by using <span
style="font-weight: bold;">-bn</span>.<br>
<br>
<a name="y"></a> The <b>-y</b> flag does a verification check on the
AtoB profile. This is done by comparing what CIE colors the
profile predicts for the test chart test patches, and comparing them
to the actual values. A summary of the average and maximum Lab delta
E's will be printed out if this flag is set. If the <b>-v</b> flag is
also set, then information for each patch will also be printed.<br>
<br>
<a name="ni"></a><a name="np"></a><a name="no"></a>Normally Lut base
profiles are
generated with three major elements:-
per
device channel (shaper) input curves, the multi-dimensional lut table,
and per PCS channel (shaper) output curves. The Using the <b>-ni</b>
flag disables the creation of the per device channel curves, while
using the <b>-no</b> flag disables the creation
of the per PCS channel curves.<br>
For LUT based profiles, the input curves that are written to the
profile are composed of two components, a shape to best match the
detailed shape of the device behavior, and a shape to distribute the
input values evenly across the LUT input indexes. The <span
style="font-weight: bold;">-no</span> flag disables the former, while
the <span style="font-weight: bold;">-np</span> flag disables the
latter. <br>
<br>
<a name="nc"></a><span style="font-weight: bold;">-nc </span>Normally
the device and CIE/spectral sample data used to create a profile is
stored in a text tag in the resulting ICC profile. To suppress this and
make the resulting profile smaller, use the <span
style="font-weight: bold;">-nc </span>flag.<br>
<br>
<a name="k"></a> -<b>k</b> parameter sets the target level of black (K)
when creating a B2A CMYK output tables. This is often called a black
level, a black inking rule, black generation, or under color
removal. These set the target black level.<br>
<br>
Possible arguments to the <b>-k</b> flag are:<br>
<br>
<b> -kz</b> selects minimum black (0.0)<br>
<b> -kh</b> selects a black value of 0.5<br>
<b> -kx</b> selects the maximum possible black (1.0)<br>
<b> -kr</b> selects a linear black ramp, starting at minimum black for
highlight, and maximum black for shadow (equivalent to -kp 0 0 1 1 1).
This is the default.<br>
<br>
<b><a name="kp"></a>-k p stle stpo enpo enle shape</b> allows an
arbitrary black value ramp to be defined, consisting of a starting
value (stle) for highlights, a breakpoint L value (stpo) where it
starts to transition to the shadow level, an end breakpoint L (enpo)
where it flattens out again, and the finishing black level (enle) for
the shadows. There is also a curve parameter, that modifies the
transition from stle to enle to either be concave (ie. the
transition starts gradually and and finished more abruptly) using
values 0.0-1.0, with 0.0 being most concave, or convex (the transition
starts more abruptly but finishes gradually), using values 1.0-2.0,
with 2.0 being the most convex.<br>
<br>
Typical black value generation curve with parameters something
like: -kp 0 .1 .9 1 .5<br>
<br>
<tt> 1.0 K |
enpo<br>
| _______
enle<br>
| /<br>
| /<br>
| /<br>
| /<br>
stle
| ------/<br>
+-------------------<br>
0.0 K
0.0 stpo 1.0<br>
White
Black<br>
</tt>
<br>
For minimum sensitivity of printed output to the lighting spectrum, it
currently seems best to use the maximum possible black, but other black
generation levels (ie. 0.3 to 0.5) may well be preferred if one wants
to
minimize the noisy appearance of black on an inkjet device, or
if the banding behaviour or other rendering flaws of the printer is to
be minimized. <br>
<br>
The <a href="xicclu.html">xicclu</a> utility can be used to plot out
the resulting black level for a given set of parameters, by using the <a
href="xicclu.html#g">-g</a> flag of a profile already created from the
same .ti3 file.<br>
<br>
<a name="K"></a> <span style="font-weight: bold;">-K parameters.</span>
Any of the <span style="font-weight: bold;">-k</span> options above
can use the <span style="font-weight: bold;">-K</span> version, in
which rather than a black value target being defined by the inking
rule, a black <span style="text-decoration: underline;">locus</span>
target is defined. For each lookup, the minimum possible black level
and the maximum possible black level is determined, the former
corresponding to a locus target of 0, and the latter corresponding to a
locus target of 1. For instance, at
the
white point, no black will be used in the output, even if the black
locus specifies a maximum (since the maximum amount of black that
can be used to print white is actually zero). Similarly, at the black
point, black may well be used, even if the black locus specifies
zero black (since a certain amount of black is needed to achieve the
desired density of color). <br>
<tt> </tt><br>
<a name="l"></a> The <b>-l</b> <i>tlimit</i> parameter sets the total
ink limit (TAC, Total Area Coverage) for the CMYK separation, as a
total percentage from 0% to 400%, and overrides any ink limit specified
in the .ti3 file. The limit value should generally be set a little
below the value used in the test chart generation, to avoid the very
edges of the gamut. If the test chart ink limit has been chosen to be a
little beyond an acceptable level, then this number should be the
acceptable level. Although
limits can be set below 200%, this will generally restrict the color
gamut
noticeably, as fully saturated secondary colors will not be reproduced.
Values are between 220% and 300% for typical printing devices.<br>
<br>
<a name="L"></a> The <b>-L</b> <i>klimit</i> parameter sets the black
channel ink limit for the CMYK separation, as a total percentage from
0%
to 100%. For printing press like devices, this can be used to prevent
the
black channel screening pattern "filling in". Typical values might be
from
95% to 99%. Note that with the current implementation this can slow
down the creation of the profile quite noticeably, so do not use <span
style="font-weight: bold;">-L</span> unless you really need to.<br>
<br>
<a name="a"></a> The <b>-a</b> parameter allows choosing an alternate
profile type. By default (equivalent
to <b>-al</b>) profile creates a <span style="font-weight: bold;">lut</span>
based table profile with a PCS
(Profile Connection Space) of L*a*b*, which generally gives the most
accurate results, and allows for the four different rendering intents
that ICC profiles
can support. A lut base table profile using a PCS of XYZ can be created
if <b>-ax</b> is used. For RGB input or display profiles, a simpler
type
of profile using either a gamma curves or a general shaper curves,
combined
with a matrix can be created, although such a profile cannot support
perceptual
or saturation intents. Gamma curve and matrix profiles can be created
by
specifying <b>-ag</b> or <b>-aG</b>, the former creating three
independent
gamma curves, one for each device channel, and the latter creating one
common curve for all the device channels. The latter may be needed with
certain applications that will not accept different gamma curves for
each
channel. General shaper curve and matrix profiles (which are superior
to
gamma curve profiles) can be created by specifying <b>-as</b> or <b>-aS</b>,
the former creating three independent shaper curves, one for each
device channel, and the latter creating one common curve for all the
device channels. The latter may be needed with certain applications
that will not accept
different shaper curves for each channel.<br>
<br>
<a name="u"></a> Lut style input profiles will normally be created
such that the white point of the test chart, will be mapped to perfect
white when used with any of the non-absolute colorimetric intents. This
is the expected behaviour for input profiles. If such a profile
is then used with a sample that has a lighter color than the original
test chart, the profile will clip the value, since it cannot be
represented in the lut table. Using the <b>-u</b> flag causes the lut
based input profile to be constructed so that the lut table contains
absolute color values, and the white of the test chart will map to its
absolute value, and any values whiter than that, will not be clipped by
the profile. The profile effectively operates in an absolute intent
mode, irrespective of what intent is selected when it is used.
This flag can be useful when an input profile is needed for using a
scanner as a "poor mans" colorimeter, or if the white point of the test
chart doesn't represent the white points of media
that will be used in practice, and that white point adjustment will be
done individually in some downstream application.<br>
<br>
<a name="i"></a> The <b>-i</b> flag allows specifying a standard or
custom illumination spectrum, applied to spectral .ti3 data to compute
PCS (Profile Connection Space) tristimulus values. <b>A</b>, <b>D50</b>,
<b>D65</b>, <b>F5</b>, <b>F8</b>, <b>F10</b> are a selection of
standard illuminant spectrums, with <b>D50</b> being the default. If a
filename is specified instead, it will be assumed to be an Argyll
specific <a href="File_Formats.html#.sp">.sp</a> custom spectrum file.
This only works if spectral data is available. Illuminant details are:<br>
<br>
A CIE tungsten
filament lamp 2848K<br>
D50 CIE daylight 5000K<br>
D65 CIE daylight 6500K<br>
F5 CIE Fluorescent
6350K, CRI 72<br>
F8 CIE Fluorescent
5000K, CRI 95<br>
F10 CIE Fluorescent 5000K,
CRI 81<br>
<br>
Custom illuminants are most often used when a fluorescent tube base
viewing booth is going to be used to view results. Other
illuminant reference files could be created using a suitable measuring
instrument such as a spectrocam, or an eyeone, although such
instruments do not provide the necessary response down to Ultra Violet
that is needed for accurate operation of Fluorescent Whitening Agent
compensation.<br>
Note that if an illuminant other than D50 is chosen, the resulting ICC
profile will not be standard, and cannot be freely interchanged with
other profiles that that us the standard D50 illuminant, particularly
if the absolute rendering intent is used. Profiles
should generally be linked with other profiles that have the same
illuminant
and observer.<br>
<br>
<a name="o"></a> The <b>-o</b> flag allows specifying a tristimulus
observer, and is used to compute PCS (Profile Connection Space)
tristimulus values. 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>
<br>
Note that if an observer other than 1931 2 degree is chosen, the
resulting ICC profile will not be standard, and cannot be freely
interchanged with other profiles that that us the standard 1931 2
degree
observer. Profiles should only be linked with other profiles that have
the same illuminant and observer. The <b>1978_2</b> observer or <span
style="font-weight: bold;">shaw</span> observer may give slightly
better results than the <b>1931_2</b> observer.<br>
<br>
<a name="f"></a> The <b>-f</b> flag enables Fluorescent Whitening
Agent (FWA) compensation. This only works if spectral data is
available, and
allows the effects of different levels of Ultra Violet in the viewing
illuminant from that used by the instrument, be compensated for. This
will only work accurately if you specify the <span
style="text-decoration: underline;">actual
illuminant spectrum
you are using to view the print</span>, using the <span
style="font-weight: bold;"><span style="font-weight: bold;">-i</span></span>
flag. If you are doing
proofing, you need to apply this to <span
style="text-decoration: underline;">both your
source profile, and your
destination profile</span>. Note that it is not sufficient to specify
an illuminant with the same white point as the one you are using, you
should specify the spectrum
of the illuminant you are <span style="text-decoration: underline;">actually
using</span> for the proofing,
including its <span style="text-decoration: underline;">Ultra Violet</span>
spectral content, otherwise FWA compensation won't work properly (but
see the note above about non-standard illuminants and observers). This
means you ideally need to measure your illuminant spectrum using an
instrument that can measure down to 300nm. Such instruments are not
easy to come by. An alternative is to simply try different illuminant
spectra in the directory,
and see if one gives you the result you are after. The ref/D50_X.X.sp
set of illuminant spectra are the D50 spectrum with different levels of
U.V. added or subtracted, ref/D50_1.0.sp being the standard D50
illuminant, and may be somewhere to start. Note that using the
ref/D50_0.0.sp spectrum with <span style="font-weight: bold;">-f</span>
gives a result that is comparable to that of a U.V. cut filter. See
also the discussion <a href="FWA.html">About Fluorescent Whitening
Agent compensation</a>.<br>
[Note: Generally using <span style="font-weight: bold;">-f</span>
with the standard D50 illuminant spectrum will predict that the device
will produce bluer output than the default of not FWA compensation.
This is because most instruments use an incandescent illuminant, which
has lower relative levels of U.V. than D50, so the FWA compensation
simulates the effect of the greater U.V. in the D50. Also note that in
an absolute colorimetric color transformation, the more a profile
predicts the output device will have blue output, the yellower the
result will be, as the overall color correction compensates for the
blueness. The opposite will happen for an input profile.]<br>
<br>
<a name="r"></a> The <b>-r</b> parameter specifies the average
deviation of device+instrument readings from the perfect, noiseless
values as a percentage. Knowing the uncertainty in the reproduction and
test patch reading can allow the profiling process to be optimized in
determining the behaviour of the underlying system. The lower the
uncertainty, the more each individual test reading can be relied on to
infer the underlying systems color behaviour at that point in the
device space. Conversely, the higher the uncertainty, the less the
individual readings can be relied upon, and the more the collective
response will have to be used. In effect, the higher the uncertainty,
the more the input test patch values will be smoothed in determining
the devices response. If the perfect, noiseless test patch values had a
uniformly distributed error of +/- 1.0% added to them, then this would
be
an average deviation of 0.5%. If the perfect, noiseless test patch
values had a normally distributed error with a standard deviation
of 1% added to them, then this would correspond to an average deviation
of 0.564%. For a lower quality instrument (less than say a Gretag
Spectrolino or Xrite DTP41), or a more variable device (such as a
xerographic print engine, rather than a good quality inkjet), then you
might be advised to increase the <span style="font-weight: bold;">-r</span>
parameter above its default value (double or perhaps 4x would be good
starting values.) <br>
<br>
<a name="S"></a><a name="s"></a><span style="font-weight: bold;">-s
-S </span>In order to generate perceptual and
saturation intent B2A tables, it is
necessary to specify at least one profile to define what source gamut
should be used in the source to destination gamut mapping. [For more
information on <span style="text-decoration: underline;">why</span> a
source gamut is needed, see <a href="iccgamutmapping.html">About ICC
profiles and Gamut Mapping</a>] The
<b>-S</b> parameter is used to do this, and doing so causes perceptual
and saturation tables to be generated. If only a perceptual
intent is needed, then the <b>-s</b> flag can be
used,
and the saturation intent will use the same table as the perceptual
intent.
Note that a input, output, display or device colororspace profile
should be
specified, not a non-device colorspace,
device
link, abstract or named color profile.<br>
If no source gamut is specified for a Lut Display profile, then an ICC
Version 2.2.0 profile will be created with only an A2B0 and B2A0 tag.
If a source gamut is specified, then an ICC Version 2.4.0 profile will
be created with a full complement of B2A tags to support all
intents. The source gamut is created from the corresponding intent
table of the provided profile to the output table being created. A TIFF
file containing an embedded ICC profile may be supplied as the argument.<br>
<br>
<a name="nP"></a><span style="font-weight: bold;">-nP</span>: Normally
when a source profile is provided to define the source gamut for the
perceptual table gamut mapping, the perceptual source table is used to
determine this gamut. This is because some profile have gamut
transformations in their perceptual A2B tables that is not in the
colorimetric A2B table, and this needs to be taken into account in
creating the perceptual B2A table, so that when the two profiles are
linked together with the perceptual intent, the gamut mapping works as
intended. The <span style="font-weight: bold;">-nP</span> option
causes the source gamut to be taken from the source profile
colorimetric table instead, causing the perceptual gamut mapping
created for the perceptual table to be from the natural source
colorspace gamut to the output space gamut.<br>
<br>
<a name="nS"></a><span style="font-weight: bold;">-nS</span>: Normally
when a source profile is provided to define the source gamut for the
saturation table gamut mapping, the saturation source table is used to
determine this gamut. This is because some profile have gamut
transformations in their saturation A2B tables that is not in the
colorimetric A2B table, and this needs to be taken into account in
creating the saturation B2A table, so that when the two profiles are
linked together with the saturation intent, the gamut mapping works as
intended. The <span style="font-weight: bold;">-nS</span> option
causes the source gamut to be taken from the source profile
colorimetric table instead, causing the saturation gamut mapping
created for the saturation table to be from the natural source
colorspace gamut to the output space gamut.<small><span
style="font-family: monospace;"></span></small><br>
<br>
<a name="g"></a>The <span style="font-weight: bold;">-g</span> flag
and its argument allow the use of a source gamut to use instead of that
of the source
profile. This is to allow optimizing the gamut mapping to a source
gamut of a particular image, which can give slightly better
results that gamut mapping from the gamut of the source colorspace.
Such a source image gamut can be created using the <a
href="tiffgamut.html"> tiffgamut</a> utility. The gamut provided to
the <span style="font-weight: bold;">-g</span> <span
style="font-weight: bold;"></span> flag should be in the
same colorspace that <span style="font-weight: bold;">colprof</span>
is using internally to connect the two profiles. For all intents except
the last one (no. <span style="font-weight: bold;">7</span>),
the space should be Jab appearance space, with the viewing
conditions generally being those of the input profile viewing
conditions. The input profile will normally be the one used to create a
source image gamut using <span style="font-weight: bold;">tiffgamut</span>.<br>
<br>
<b><a name="p"></a></b>The <b>-p</b> option alows specifying an
abstract
profile be applied to all of the output tables, after any gamut
mapping. An abstract
profile is a way of specifying a color adjustment in a device
independent way. The abstract profile might have been created using one
of the <span style="font-weight: bold;">tweak</span> tools, such as <a
href="refine.html">refine</a>.<br>
<br>
One strategy for getting the best perceptual results when using ICC
profiles with systems that don't accept device link profiles, is as
follows: Specify a gamut mapping profile of opposite type to the type
of device being profiled, and when linking, use the relative
colorimetric intent if the two profiles are of the same type, and
perceptual intent if the two profiles are of the opposite type. For
instance, if you are
creating a CMYK output profile, specify an RGB profile for the <b>-s</b>
or <b>-S</b> parameter. If linking that profile with a CMYK source
profile,
use relative colorimetric intent, or if linking with an RGB profile,
use
the perceptual intent. Conversely, if creating an RGB output profile,
specify
a CMYK profile for the <b>-s</b> or <b>-S</b> parameter, and if
linking
that profile with an RGB source profile, use relative colorimetric
intent,
or if linking with a CMYK profile, use the perceptual intent.<br>
<br>
<a name="t"></a><a name="T"></a>Normally, the gamut mapping used in
creating the perceptual and
saturation intent tables is set to perceptual and saturation gamut
mapping (as would be expected), but it is possible to override this
default selection for each intent using the <b>-t</b> and <b>-T</b>
flags. The <b>-t</b> flag can be used to set the
gamut mapping for the perceptual table, and the <b>-T</b>
flag can be used to set the gamut mapping for the saturation table. A
more detailed description of the different intents is given in <a
href="collink.html#i">collink</a>. Note that selecting any of the
absolute intents will
probably not function as expected, since the perceptual and saturation
tables are inherently relative
colorimetric in nature.<br>
<br>
<a name="c"></a><b><a name="d"></a></b>Since appearance space is used
in the gamut mapping (just as it
is in <a href="collink.html"> collink</a>), the viewing conditions
for the source and destination colorspaces should really be specified.
The
source colorspace is the profile specified with the <b>-s</b> or <b>-S</b>
flag, and the destination is the profile being created. The <b>-c</b>
and <b>-d</b> options allow specification
of their respective, associated viewing conditions. The viewing
condition
information is used to map the profile PCS (Profile Connection Space,
which
us either XYZ or L*a*b*) color into appearance space (CIECAM02), which
is
a better colorspace to do gamut mapping in. The viewing conditions
allow
the conversion into appearance space to take account of how color will
be
seen under particular viewing conditions. <br>
<br>
Viewing conditions can be specified in two basic ways. One is to select
from the list of "pre canned", enumerated viewing conditions, choosing
one that is closest to the conditions that are appropriate for the
media type and situation. Alternatively, the viewing conditions
parameters can be specified individually. If both methods are
used, them the chosen enumerated condition will be used as a base, and
its parameters will then be individually overridden.<br>
<br>
Appearance space is also used to provide a space to map any remaining
out of gamut colors (after a possible gamut mapping has been applied)
into the device gamut. <br>
<br>
<b><a name="P"></a></b>The <b>-P</b> option causes diagnostic 3D <a
href="File_Formats.html#VRML">VRML</a> plots to be created that
illustrate the gamut mappings generated for the perceptual and
saturation intent tables.<span style="font-weight: bold;"></span><br>
<br>
<a name="p1"></a> The final parameter is the file base name for the <a
href="File_Formats.html#.ti3">.ti3</a> input test point data, and the
resulting <a href="File_Formats.html#ICC">ICC</a> output profile (.icm
extension on the MSWindows platform, .icc on Apple or Unix platforms).<br>
<h3>Discussion</h3>
Note that monochrome profiling isn't currently supported. It may be
supported sometime in the future.<br>
<br>
If the <b>-v</b> flag is used (verbose), then at the end of creating a
profile,
the maximum and average fit error of the input points to the resulting
profile
will be reported. This is a good guide as to whether things have gone
smoothly
in creating a profile. Depending on the type of device, and the
consistency
of the readings, average errors of 5 or less, and maximum errors of 15
or
less would normally be expected. If errors are grossly higher than
this,
then this is an indication that something is seriously wrong with the
device
testing, or profile creation.<br>
<br>
Given a .ti3 file from a display device that contains display RAMDAC
calibration information (generated by <a href="dispcal.html">dispcal</a>,
passed through <a href="dispread.html">dispread</a>), <span
style="font-weight: bold;">colprof</span> will convert this into a <span
style="font-weight: bold;">vcgt</span> tag in the resulting profile,
so that the operating system utilities can configure the display
hardware appropriately, whenever the profile is used.<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
</body>
</html>
distrib
>
Mandriva
>
2010.0
>
i586
>
media
>
contrib-release
>
by-pkgid
>
56e231b080a119bc733fcd74872c9f3d
>
files
>
237
