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+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<html>
+ <head>
+ <title>refine</title>
+ <meta http-equiv="content-type" content="text/html;
+ charset=ISO-8859-1">
+ <meta name="author" content="Graeme Gill">
+ </head>
+ <body>
+ <h2><b>tweak/refine</b></h2>
+ <h3>Summary</h3>
+ <span style="font-weight: bold;">Refine</span> creates an abstract
+ profile, by comparing CIE measurement values from two test charts.
+ The charts will usually be in <a href="File_Formats.html#.ti3">.ti3</a>
+ format, but only XYZ, Lab or spectral values will be used (ie. all
+ device space values are ignored). Typically the charts would be
+ printed on a target system (the one being emulated, say a printing
+ press), and the proofing system (the one that is being profiled).
+ The abstract profile that <span style="font-weight: bold;">refine</span>
+ produces will be a correction that makes the proofing system behave
+ more like the target. This can then be used to recreate the proofing
+ systems ICC profile, or device link. By feeding a previous abstract
+ correction profile in as well, iterative improvement can be made to
+ the proofing reproduction.<br>
+ <br>
+ <a href="verify.html">verify</a> is a useful tool to use on the two
+ test charts, to check how well the refinement is proceeding. If a
+ white point relative match is being created (refine -R), then use
+ veryify -N.<br>
+ <h3>Usage Summary</h3>
+ <tt><small>usage: refine [-options] cietarget ciecurrent [outdevicc]
+ [inabs] outabs<br>
+ &nbsp;-v&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
+ Verbose<br>
+ &nbsp;-c&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Create
+
+ initial abstract correction profile<br>
+ &nbsp;-g&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Don't
+
+ impose output device gamut limit<br>
+ &nbsp;-r res&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Set
+ abstract profile clut resolution (default 33)<br>
+ &nbsp;-d factor&nbsp;&nbsp;&nbsp;&nbsp; Override default damping
+ factor (default 0.950000)<br>
+ &nbsp;-R&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Aim
+
+ for white point relative match rather than absolute<br>
+ &nbsp;</small></tt><tt><small><small></small><small><small>-f
+ [illum]&nbsp;&nbsp;&nbsp; Use Fluorescent Whitening Agent
+ compensation [opt. simulated inst. illum.:<br>
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
+
+ M0, M1, M2, A, C, D50 (def.), D50M2, D65, F5, F8, F10 or
+ file.sp]<br>
+ &nbsp;-i illum&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Choose
+ illuminant for computation of CIE XYZ from spectral data
+ &amp; FWA:<br>
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
+
+ A, C, D50 (def.), D50M2, D65, F5, F8, F10 or file.sp</small></small><br>
+ &nbsp;-o observ&nbsp;&nbsp;&nbsp;&nbsp; Choose CIE Observer for
+ spectral data:<br>
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+1931_2,
+
+ 1964_10, S&amp;B 1955_2, J&amp;V 1978_2 (def.)<br>
+ &nbsp;<span style="font-style: italic;">cietarget&nbsp;</span>&nbsp;&nbsp;&nbsp;
+ Target CIE or spectral values, CGATS file (e.g. .ti3)<br>
+ &nbsp;<span style="font-style: italic;">ciecurrent</span>&nbsp;&nbsp;&nbsp;
+ Actual CIE or spectral values, CGATS file (e.g. .ti3)<br>
+ &nbsp;[<span style="font-style: italic;">outdevicc</span>]&nbsp;&nbsp;
+ Output device ICC profile to set gamut limit (not used if -g)<br>
+ &nbsp;[<span style="font-style: italic;">inabs</span>]&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Previous
+
+ abstract correction ICC profile (not used if -c)<br>
+ &nbsp;<span style="font-style: italic;">outabs</span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Created/refined
+
+ abstract correction ICC profile</small></tt><br>
+ <h3>Usage Details</h3>
+ <b>refine</b> provides a way of improving the profile accuracy of a
+ proofing system.<br>
+ <br>
+ The <b>-v</b> flag prints out extra information during the
+ checking, and prints each patch value, rather than just a summary.<br>
+ <br>
+ The <b>-c</b> option is used when refine is being used for the
+ first time, and there is no previous abstract profile to continue
+ refining. If <span style="font-weight: bold;">-c</span> is used,
+ then the name of the previous abstract correction profile should not
+ be supplied.<br>
+ <br>
+ If the <b>-g </b>flag indicates that an output device profile is
+ not being supplied, and that corrections should be attempted, even
+ if the colors are outside the devices gamut. Normally an output
+ device profile is supplied, and corrections aren't applied to colors
+ outside the devices gamut, since this will not achieve anything
+ useful, and can distort the results.<br>
+ <br>
+ If the <b>-r </b>parameter overrides the resolution of the CLUT
+ grid used in the abstract profile. By default the value is 33, but
+ other<br>
+ values can be chosen. An odd number is recommended. <br>
+ <br>
+ If the <b>-d </b>parameter sets how aggressively refine should try
+ and correct errors. Normally it will try and exactly compensate for
+ the color errors revealed in comparing the two measurement files,
+ but if the device behaviour is unusual, or not very repeatable, this
+ may result in successive applications of refine making things worse,
+ rather than better. If this is the case, try using a smaller number,
+ such as 0.8, or 0.5.<br>
+ <br>
+ If the <span style="font-weight: bold;">-R</span> flag is used,
+ then refine creates an abstract profile for improving the match of
+ the patch values when&nbsp; interpreted in a white point relative
+ (ie. Relative Colorimetric) intent. If used to create a corrected
+ device link profile using <a href="collink.html">collink</a>,
+ remember to create a Relative colorimetric intent device link
+ profile.<br>
+ <br>
+ The <b>-f</b> flag enables Fluorescent Whitening Agent (FWA)
+ compensation. This only works if spectral data is available and, the
+ instrument is not UV filtered.&nbsp; FWA compensation adjusts the
+ spectral samples so that they appear to have been measured using an
+ illuminant that has a different level of Ultra Violet to the one the
+ instrument actually used in the measurement. The optional
+ illumination parameter allows specifying a standard or custom
+ illumination spectrum to be used as the similated instrument
+ illuminant, overriding the default <b>D50</b> or CIE computation
+ illuminant used for FWA (see <b>-i</b> below<b>). </b>See <a
+ href="file:///D:/src/argyll/doc/colprof.html#f">colprof -f</a> for
+ a fuller explanation. The same value should be used as was used
+ during the creation of the profile.<br>
+ <br>
+ The <b>-i</b> flag allows specifying a standard or custom
+ illumination spectrum, applied to the spectral test point values to
+ compute CIE tristimulus values. <b>A</b>, <b>D50</b>, <b>D50M2,
+ 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:///D:/src/argyll/doc/File_Formats.html#.sp">.sp</a>
+ spectrum file. If FWA compensation is used during measurement, this
+ illuminant will be used by default as the simulated instrument
+ illuminant. The same value should be used as was used during the
+ creation of the profile.<br>
+ <br>
+ The <b>-o</b> flag allows specifying a tristimulus observer, and is
+ used to compute CIE tristimulus values. The following choices are
+ available:<br>
+ <b>&nbsp; 1931_2</b> selects the standard CIE 1931 2 degree
+ observer.<br>
+ &nbsp; <b>1964_10</b> selects the standard CIE 1964 10 degree
+ observer.<br>
+ &nbsp; <b>1955_2</b> selects the Stiles and Birch 1955 2 degree
+ observer<br>
+ &nbsp; <b>1978_2 </b>selects the Judd and Voss 1978 2 degree
+ observer<br>
+ &nbsp; <b>shaw</b> selects the Shaw and Fairchild 1997 2 degree
+ observer<br>
+ <br>
+ If both CIE and spectral values are present in the input files, the
+ CIE values will be used by default. Using the <span
+ style="font-weight: bold;">-i</span>, <span style="font-weight:
+ bold;">-o</span> or <span style="font-weight: bold;">-f</span>
+ flag will force spectral values to be used. The the <span
+ style="font-weight: bold;">-i</span>, <span style="font-weight:
+ bold;">-o</span> or <span style="font-weight: bold;">-f</span>
+ flags will apply to both the target and measured input files.<br>
+ <br>
+ <span style="font-style: italic; font-weight: bold;">cietarget</span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Is
+
+ the filename of the target CIE or spectral values. This is a <a
+ href="File_Formats.html#CGATS">CGATS</a> file (e.g. a <a
+ href="File_Formats.html#.ti3">.ti3</a> made using <a
+ href="chartread.html">chartread</a>). These are the color values
+ wanted for each patch in the test chart, typically the product of
+ the target print system.<br>
+ <br>
+ <span style="font-style: italic; font-weight: bold;">ciecurrent</span>
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Is the filename of the
+ actual, current measured CIE or spectral values. This is a <a
+ href="File_Formats.html#CGATS">CGATS</a> file (e.g. a <a
+ href="File_Formats.html#.ti3">.ti3</a> made using <a
+ href="chartread.html">chartread</a>). The errors between these
+ patches and the patches in the <span style="font-style: italic;
+ font-weight: bold;">cietarget</span> file will be used to create a
+ correction profile.<br>
+ <br>
+ &nbsp;[<span style="font-style: italic; font-weight: bold;">outdevicc</span>]&nbsp;&nbsp;&nbsp;&nbsp;
+If
+
+ the <span style="font-weight: bold;">-g</span> flag is not used,
+ then the output device ICC profile should be supplied here, to allow
+ <span style="font-weight: bold;">refine</span> to limit its
+ corrections to colors that are within the gamut of the device.<br>
+ <br>
+ &nbsp;[<span style="font-weight: bold; font-style: italic;">inabs</span>]&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+After
+
+ the first correction has been created, subsequent corrections need
+ to improve upon previous ones, so the previous correction profile
+ should be provided here. For the first correction, the <span
+ style="font-weight: bold;">-c</span> flag should be used, and this
+ argument is omitted.<br>
+ <br>
+ &nbsp;<span style="font-weight: bold; font-style: italic;">outabs</span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+The
+
+ name of the created or refined abstract correction ICC profile<br>
+ <br>
+ <h3> Discussion</h3>
+ <span style="font-weight: bold;">Refine</span> is typically used in
+ a proofing situation, in which a verification chart is being used to
+ check the accuracy of a proofing system. (It might also be used for
+ more arbitrary color alterations by created two test chart files by
+ hand.) By using the errors between the target chart and the measured
+ values, refine attempts to improve the match between the proofing
+ system and its target.<br>
+ <br>
+ There is facility in <a href="collink.html">collink</a>, <a
+ href="colprof.html">colprof</a> and <a href="revfix.html">revfix</a>
+ to incorporate an abstract profile. <br>
+ <br>
+ For systems using two device profiles or a device link to convert
+ between the target space printing files and the proofing device
+ space, the following would be a typical scenario:<br>
+ <br>
+ <div style="margin-left: 40px;">We have a reference set of test
+ chart values, read from the target system <span
+ style="font-weight: bold;">reference.ti3</span>. The ICC profile
+ for the target system is <span style="font-weight: bold;">target.icm</span>.
+ The ICC profile for the proofing system is <span
+ style="font-weight: bold;">proofer.icm</span>. If using a device
+ link, the device link used to print proofer test charts is
+ currently <span style="font-weight: bold;">target_proofer.icm</span>:<br>
+ <br>
+ <br>
+ First we print the test chart out on the proofing system and read
+ it in, resulting in a <span style="font-weight: bold;">chart1.ti3</span>
+ file.<br>
+ <br>
+ Lets check how well the proofing system current matches using
+ verify:<br>
+ <br>
+ &nbsp;&nbsp;&nbsp; verify&nbsp; reference.ti3 chart1.ti3<br>
+ <br>
+ We then create our initial abstract correction fix profile <span
+ style="font-weight: bold;">fix1.icm</span> using refine:<br>
+ <br>
+ &nbsp;&nbsp;&nbsp; refine -v -c&nbsp; reference.ti3 chart1.ti3
+ proofer.icm fix1.icm<br>
+ <br>
+ Applying this to your process for creating the proofer device
+ profile or target to proofing device link (choose one of the three
+ options below, depending whether you are using the proofer profile
+ and just want to alter its colorimetric B2A table using <span
+ style="font-weight: bold;">revfix</span>, whether you are going
+ to recreate the proofer file from the original measurement data
+ using&nbsp; <span style="font-weight: bold;">colprof</span>, or
+ whether you are using a device link profile created using <span
+ style="font-weight: bold;">collink</span>):<br>
+ <br>
+ &nbsp;&nbsp;&nbsp; revfix -v -1 -ke -p fix1.icm proofer.icm
+ proofer_fix1.icm<br>
+ or<br>
+ &nbsp;&nbsp;&nbsp; copy proofer.ti3 proofer_fix1.ti3<br>
+ &nbsp;&nbsp;&nbsp; colprof -v -p fix1.icm proofer_fix1<br>
+ or<br>
+ &nbsp;&nbsp;&nbsp; collink -v -s -ia -oa -p fix1.icm target.icm
+ proofer.icm target_proofer_fix1.icm<br>
+ <br>
+ Note that the above example is a simple one - you should use all
+ the same options as you used to create your initial <span
+ style="font-weight: bold;"><span style="font-weight: bold;"></span>proofer.icm&nbsp;
+
+ </span>or <span style="font-weight: bold;">target_proofer.icm</span>,
+ with the addition of the "-p fix1.icm" option to specify the
+ abstract correction profile be applied.<br>
+ <br>
+ Use the <span style="font-weight: bold;">proofer_fix1.icm</span>
+ or <span style="font-weight: bold;">target_proofer_fix1.icm</span>
+ to print out the test chart again, and read it in, resulting in <span
+ style="font-weight: bold;">chart2.ti3</span> file.<br>
+ <br>
+ Lets check how well the proofing system matches after this first
+ round of refinement using verify:<br>
+ <br>
+ &nbsp;&nbsp;&nbsp; verify&nbsp; reference.ti3 chart2.ti3<br>
+ <br>
+ <br>
+ <span style="font-weight: bold;"><span style="font-weight: bold;">&gt;&gt;&gt;</span></span><br>
+ <span style="font-weight: bold;"><span style="font-weight: bold;"></span></span><br>
+ <span style="font-weight: bold;"><span style="font-weight: bold;">&nbsp;</span></span>We
+can
+
+ then start another round of improvement:<br>
+ <br>
+ We refine our previous abstract correction fix profile using
+ refine:<br>
+ <br>
+ &nbsp;&nbsp;&nbsp; refine -v&nbsp; reference.ti3 chart2.ti3
+ proofer.icm fix1.icm fix2.icm<br>
+ <br>
+ Applying this new abstract profile to our process for creating the
+ proofing device profile or link again:<br>
+ <br>
+ &nbsp;&nbsp;&nbsp; revfix -v -1 -ke -p fix2.icm proofer.icm
+ proofer_fix2.icm<br>
+ or<br>
+ &nbsp;&nbsp;&nbsp; copy proofer.ti3 proofer_fix2.ti3<br>
+ &nbsp;&nbsp;&nbsp; colprof -v -p fix2.icm proofer_fix2<br>
+ or<br>
+ &nbsp;&nbsp;&nbsp; collink -v -s -ia -oa -p fix2.icm target.icm
+ proofer.icm target_proofer_fix2.icm<br>
+ <br>
+ Use the <span style="font-weight: bold;">proofer_fix2.icm</span>
+ or <span style="font-weight: bold;">target_proofer_fix2.icm</span>
+ to print out the test chart again, and read it in, resulting in <span
+ style="font-weight: bold;">chart3.ti3</span> file.<br>
+ <br>
+ Check again how well the proofing system matches after this first
+ round of refinement using verify:<br>
+ <br>
+ &nbsp;&nbsp;&nbsp; verify&nbsp; reference.ti3 chart3.ti3<br>
+ <br>
+ Rounds of improvements can be continues by looping back to <span
+ style="font-weight: bold;">&gt;&gt;&gt;</span>, being careful to
+ increment the names of the <span style="font-weight: bold;">fixN.icm</span>,&nbsp;
+
+ <span style="font-weight: bold;">proofer_fixN.icm</span> or <span
+ style="font-weight: bold;">target_proofer_fixN.icm</span> and <span
+ style="font-weight: bold;">chartN.ti3</span>files. Stop when
+ exhausted, or if it looks like things are getting worse, rather
+ than better. If the latter happens, it might be good to revert to
+ the results from a previous round.<br>
+ </div>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ </body>
+</html>