summaryrefslogtreecommitdiff
path: root/doc/printcal.html
diff options
context:
space:
mode:
authorJörg Frings-Fürst <debian@jff-webhosting.net>2014-09-01 13:56:46 +0200
committerJörg Frings-Fürst <debian@jff-webhosting.net>2014-09-01 13:56:46 +0200
commit22f703cab05b7cd368f4de9e03991b7664dc5022 (patch)
tree6f4d50beaa42328e24b1c6b56b6ec059e4ef21a5 /doc/printcal.html
Initial import of argyll version 1.5.1-8debian/1.5.1-8
Diffstat (limited to 'doc/printcal.html')
-rw-r--r--doc/printcal.html399
1 files changed, 399 insertions, 0 deletions
diff --git a/doc/printcal.html b/doc/printcal.html
new file mode 100644
index 0000000..89264c5
--- /dev/null
+++ b/doc/printcal.html
@@ -0,0 +1,399 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<html>
+ <head>
+ <title>printcal</title>
+ <meta http-equiv="content-type" content="text/html;
+ charset=ISO-8859-1">
+ <meta name="author" content="Graeme W. Gill">
+ </head>
+ <body>
+ <h2> profile/printcal</h2>
+ <h3>Summary</h3>
+ Create a printer linearization calibration file from <a
+ href="File_Formats.html#.ti3">.ti3</a> test chart patch values.<br>
+ <h3>Usage Summary</h3>
+ &nbsp;<span style="font-family: monospace;">printcal</span><small
+ style="font-family: monospace;"> [-<i>options</i>] [prevcal]
+ inoutfile<br>
+ &nbsp;<a href="#v">-v verbosity</a> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+ Set verbosity level<br>
+ </small><small style="font-family: monospace;">&nbsp;<a href="#p">-p</a>
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;
+ &nbsp; Plot graphs.<br>
+ &nbsp;<a href="#i">-i</a>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+&nbsp;
+
+ &nbsp; &nbsp; &nbsp;&nbsp; Initial calibration, set targets,
+ create .cal<br>
+ </small><small style="font-family: monospace;">&nbsp;<a href="#r">-r</a>
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;
+ &nbsp;&nbsp; Re-calibrate against previous .cal and create new
+ .cal</small><br style="font-family: monospace;">
+ <span style="font-family: monospace;"></span><small
+ style="font-family: monospace;">&nbsp;<a href="#e">-e</a>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+&nbsp;
+&nbsp;
+
+ &nbsp; &nbsp;&nbsp; Verify against previous .cal<br>
+ </small><small style="font-family: monospace;">&nbsp;<a href="#I">-I</a>
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;
+ &nbsp;&nbsp; Create imitation target from .ti3 and null
+ calibration</small><br>
+ <small style="font-family: monospace;">&nbsp;<a href="#d">-d</a>
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;
+ &nbsp;&nbsp; Go through the motions but don't write any files</small><br
+ style="font-family: monospace;">
+ <small><span style="font-family: monospace;">&nbsp;</span><a
+ style="font-family: monospace;" href="#A">-A "manufacturer"</a><span
+ style="font-family: monospace;">&nbsp; Set the manufacturer
+ description string</span><br style="font-family: monospace;">
+ <span style="font-family: monospace;">&nbsp;</span><a
+ style="font-family: monospace;" href="#M">-M "model"</a><span
+ style="font-family: monospace;">
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Set the model
+ description string</span><br style="font-family: monospace;">
+ <span style="font-family: monospace;">&nbsp;</span><a
+ style="font-family: monospace;" href="#D">-D "description"</a><span
+ style="font-family: monospace;">&nbsp;&nbsp; Set the profile
+ Description string </span><br style="font-family: monospace;">
+ <tt>&nbsp;</tt><tt><a href="#C">-C "copyright"</a></tt><tt>
+ &nbsp;&nbsp;&nbsp; Set the copyright string</tt><tt><br>
+ </tt><tt> </tt><tt>&nbsp;</tt><tt><a href="#x">-x# percent</a></tt><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Set
+initial
+
+ maximum device % target (override auto)</tt><tt><br>
+ </tt></small><small><span style="font-family: monospace;"><small>&nbsp;<a
+ href="#m">-m# percent</a>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
+ Set initial dev target to % of auto maximum<br>
+ </small>&nbsp;<a href="#n">-n# deltaE</a>
+ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Set initial white
+ minimum deltaE target<br>
+ &nbsp;<a href="#t">-t# percent</a>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Set
+initial
+
+ 50% transfer curve percentage target<br style="font-family:
+ monospace;">
+ <span style="font-family: monospace;">&nbsp;&nbsp; # = c, r,
+ 0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; First channel</span><br
+ style="font-family: monospace;">
+ <span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+m,
+g,
+1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
+ Second channel</span><br style="font-family: monospace;">
+ <span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+y,
+b,
+2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
+ Third channel</span><br style="font-family: monospace;">
+ <span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+k,&nbsp;&nbsp;&nbsp;
+3&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Fourth
+
+ channel, etc.<br>
+ &nbsp;<a href="#a">-a</a>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Create
+an
+
+ Adobe Photoshop .AMP file as well as a .cal<br
+ style="font-family: monospace;">
+ </span><span style="font-family: monospace;">&nbsp;</span><a
+ style="font-family: monospace;" href="#p1">prevcal</a><span
+ style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Base
+name
+
+ of previous .cal file for recal or verify.</span><br
+ style="font-family: monospace;">
+ <span style="font-family: monospace;">&nbsp;</span><a
+ style="font-family: monospace;" href="#p2">inoutname</a><span
+ style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+Base
+name
+
+ of input .ti3 file, output .cal file</span><br>
+ </span><span style="font-family: monospace;"></span></small><small><span
+ style="font-family: monospace;"></span><span style="font-family:
+ monospace;"></span><span style="font-family: monospace;"></span></small><br>
+ <h3>Options<br>
+ </h3>
+ <b><a name="v"></a>-v</b>&nbsp; Turn on verbose mode. Gives progress
+ information as the calibration is created. An argument greater than
+ 1 increases the verbosity. Will also report the ideal power value to
+ apply to the test chart in targen.<br>
+ <br>
+ <a name="p"></a><span style="font-weight: bold;">-p</span> Turns on
+ plot mode. This causes various graphs to be plotted as the
+ calibration is created. The channels will be plotted in the graph
+ colors: Blue, Red, Yellow, Black, Green, Purple, Brown, Orange,
+ Grey, White.<br>
+ <br>
+ <a name="i"></a><span style="font-weight: bold;">-i</span> Select
+ initial calibration mode. Initial calibration mode allows setting
+ the targets for the calibration, such as maximum device percentage,
+ minimum white level, and the transfer curve shape. The second last
+ parameter <span style="font-weight: bold;"><span
+ style="font-weight: bold;"></span>prevcal</span> is not used in
+ this mode.<br>
+ <br>
+ <a name="r"></a><span style="font-weight: bold;">-r</span> Turns on
+ re-calibration mode. This is used for calibrations after the initial
+ one, where the aim is to return the devices response to the same
+ state as it was after the initial caibration. Parameters that affect
+ the calibration targets are ignored. The second last parameter <span
+ style="font-weight: bold;"><span style="font-weight: bold;"></span>prevcal</span>
+ is used to establish what the targets for the calibration are.<br>
+ <br>
+ <a name="e"></a><span style="font-weight: bold;">-e</span> Turns on
+ verify mode. In this mode the test chart input is verified agains
+ the expected response in the <span style="font-weight: bold;"><span
+ style="font-weight: bold;"></span>prevcal</span> file.<br>
+ <br>
+ <a name="I"></a><span style="font-weight: bold;">-I</span> Similar
+ to <span style="font-weight: bold;">-i</span>, except that rather
+ than creating a linear target curve and corresponding calibration,
+ it takes the given behaviour as an absolute target and create a
+ corresponding null set of calibration curves. This .cal can then be
+ used to recalibrate a similar device (or the same device at some
+ other time) to imitate the behaviour of the initial device. The
+ second last parameter <span style="font-weight: bold;"><span
+ style="font-weight: bold;"></span>prevcal</span> is not used in
+ this mode. Parameters that affect the calibration targets are
+ ignored.<br>
+ <br>
+ <a name="d"></a><span style="font-weight: bold;">-d</span> Disables
+ the writing of any files, causing printcal to go through the motions
+ without changing anything.<br>
+ <br>
+ <a name="A"></a>The <b>-A</b> parameter allows setting of the
+ device manufacturer description string in the calibration file. 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 device manufacturer description
+ string will be put in the calibration file.<br>
+ <br>
+ <a name="M"></a>The <b>-M</b> parameter allows setting of the
+ device mode description string in the calibration file. 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 will be put
+ in the calibration file.<br>
+ <br>
+ <a name="D"></a>The <b>-D</b> parameter allows setting of the
+ profile description string in the calibration file. 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. By default no profile description
+ string will be put in the calibration file.<br>
+ <br>
+ <a name="C"></a>The <b>-C</b> parameter allows setting of the
+ profile copyright string in the calibration file. 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 no copyright string will be put in the
+ calibration file.<br>
+ <br>
+ <a name="x"></a> The <b>-x</b> parameter allows overriding the
+ default auto maximum device target value computed from the raw
+ device response for the initial calibration. The default uses a
+ heuristic to decide when the response of the device to each channels
+ colorant value reaches the point of diminishing returns, while the <span
+ style="font-weight: bold;">-x</span> parameter allows this default
+ to be overridden. The <span style="font-weight: bold;">-x</span>
+ paramater can be used multiple times, once for each channel that is
+ being set. The <span style="font-weight: bold;">-x</span> should be
+ followed by the channel number between 0 and 15, or the aliases <span
+ style="font-weight: bold;">r</span>, <span style="font-weight:
+ bold;">g</span> or <span style="font-weight: bold;">g</span>, or
+ <span style="font-weight: bold;">c</span>, <span
+ style="font-weight: bold;">m</span>, <span style="font-weight:
+ bold;">y</span> or <span style="font-weight: bold;">k,</span> and
+ the channel number should then be followed by the device value as a
+ percentage. <span style="font-weight: bold;">NOTE</span> that you
+ will probably get sub-optimal results if you force a device maximum
+ that is beyond the point of maximum response of a device channel,
+ since this will have the effect of <span style="text-decoration:
+ underline;">reducing</span> the device response. If you want to
+ set a conservative target to allow for recalibration later, see the
+ <b>-m</b> flag below.<br>
+ <br>
+ <a name="m"></a> The <b>-m</b> parameter allows modifying the
+ default auto maximum device target value for the initial
+ calibration. The auto maximum is computed as described above, and is
+ then scaled by the <b>-m</b> parameter value. Typically this will
+ be a scale down (ie. <b>90%</b>) to allow some margin to increase
+ the channel value if the channel density drops in a future
+ recalibration. Scaling the maximum down will reduce gamut, but
+ allows scope for stable behaviour using calibration. The <span
+ style="font-weight: bold;">-m</span> paramater can be used
+ multiple times, once for each channel that is being set. The <span
+ style="font-weight: bold;">-m</span> should be followed by the
+ channel number between 0 and 15, or the aliases <span
+ style="font-weight: bold;">r</span>, <span style="font-weight:
+ bold;">g</span> or <span style="font-weight: bold;">g</span>, or
+ <span style="font-weight: bold;">c</span>, <span
+ style="font-weight: bold;">m</span>, <span style="font-weight:
+ bold;">y</span> or <span style="font-weight: bold;">k,</span> and
+ the channel number should then be followed by the deltaE value.<span
+ style="font-family: monospace;"></span><br>
+ <br>
+ <a name="n"></a> The <b>-n</b> parameter allows overriding the
+ default minimum deltaE of a colorant to white of 0. This can be used
+ to set a minimum colorant level in order to emulate media darker or
+ of a different tint. The <span style="font-weight: bold;">-n</span>
+ paramater can be used multiple times, once for each channel that is
+ being set. The <span style="font-weight: bold;">-n</span> should be
+ followed by the channel number between 0 and 15, or the aliases <span
+ style="font-weight: bold;">r</span>, <span style="font-weight:
+ bold;">g</span> or <span style="font-weight: bold;">g</span>, or
+ <span style="font-weight: bold;">c</span>, <span
+ style="font-weight: bold;">m</span>, <span style="font-weight:
+ bold;">y</span> or <span style="font-weight: bold;">k,</span> and
+ the channel number should then be followed by the deltaE value.<span
+ style="font-family: monospace;"></span><br>
+ <br>
+ <a name="t"></a> The <b>-t</b> parameter allows setting a target
+ linearization curve that is other than purely visual linear. The
+ default is to create a calibration curve that results in a perfectly
+ even change in output for each change in the calibrated device
+ value, as measured by steps in delta E94. The <span
+ style="font-weight: bold;">-x</span> parameter allows setting a
+ target curve above or below the perfectly visual linear, by setting
+ the aim value at 50% input. An aim higher than 50% will cause that
+ channel to become more intense by the 50% mark, while a value lower
+ than 50% will cause the channel to become less intense by the 50%
+ mark than perfectly linear.The <span style="font-weight: bold;">-x</span>
+ should be followed by the channel number between 0 and 15, or the
+ aliases <span style="font-weight: bold;">r</span>, <span
+ style="font-weight: bold;">g</span> or <span style="font-weight:
+ bold;">g</span>, or <span style="font-weight: bold;">c</span>, <span
+ style="font-weight: bold;">m</span>, <span style="font-weight:
+ bold;">y</span> or <span style="font-weight: bold;">k,</span> and
+ the channel number should then be followed by the device value as a
+ percentage.<br>
+ <br>
+ <a name="a"></a><span style="font-weight: bold;">-a</span> Creates
+ an Adobe Photoshop <span style="font-weight: bold;">.AMP</span>
+ format curves file as well as a .cal.<br>
+ <span style="font-weight: bold;"></span><br>
+ <a name="p1"></a> The optional second last parameter is the file
+ base name for a previous <a href="File_Formats.html#CAL">.cal</a>
+ calibration file, used as the target reference for recalibrate and
+ verify modes. <br>
+ <br>
+ <a name="p2"></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#CAL">.cal</a> calibration
+ file output. <br>
+ <h3><a name="DISCUSSION"></a>Discussion</h3>
+ <span style="font-weight: bold;">Printcal</span> is a tool for
+ creating per device channel linearization curves for printing
+ devices.<br>
+ <br>
+ As input it takes a .ti3 file containing the results of printing a
+ test chart on the <span style="text-decoration: underline;">non-color
+
+ managed</span>, <span style="text-decoration: underline;">non-calibrated</span>
+ device, and measuring it. The test chart consists of step wedges for
+ each of the device primary colors, from the media white to full
+ individual colorant intensity.<br>
+ <br>
+ For the initial calibration (<span style="font-weight: bold;">-i</span>),
+the
+range
+
+ of device values to be used and the shape of the target
+ linearization curve are established, as well as creating the first
+ set of calibration curves. For subsequent re-calibrations (<span
+ style="font-weight: bold;">-r</span>), the calibration curves aim
+ to reproduce the same response as the original calibration. If a
+ test chart is printed with calibration enabled and then is measured,
+ it can be used to verify the calibration against the expected
+ response (<span style="font-weight: bold;">-e</span>).<br>
+ <br>
+ As each colorant steps through the test wedge patches from media
+ white, they trace out a measured locus in CIE L*a*b* colorspace.
+ Each channel response is evaluated by computing the CIE DeltaE to
+ media white of the response to a change in each individual channel
+ of each locus. This measure is used to determine when the devices
+ response to a colorant level is reaching diminishing returns,
+ setting a maximum colorant value. This measure can also be used to
+ set a minimum colorant value for the purposes of emulating a
+ different media color. The default maximum and minimum values for
+ each colorant can be overridden using the <span style="font-weight:
+ bold;">-x</span> and <span style="font-weight: bold;">-n</span>
+ parameters. The automatically determined maximum may be modified
+ (scaled) using the <b>-m</b> parameter, which can be useful in
+ allowing some margin for future calibrations to compensate for a
+ drop in density.<br>
+ <br>
+ The actual linearization uses a subtly different measure, which is
+ the CIE DelataE 94 along each colorant response locus, ensuring that
+ after linearization each step in colorant value is subjectively
+ even. The linearization aim can be altered from a purely linear
+ curve by using the <span style="font-weight: bold;"><span
+ style="font-weight: bold;">-t</span></span> parameters.<br>
+ <br>
+ After the initial calibration, the device can be re-calibrated (<span
+ style="font-weight: bold;">-r</span>) by printing a calibration
+ test chart under the same conditions as the initial one, but with
+ the calibration aimed at reproducing the same response as the
+ initial calibration, rather that setting new targets.<br>
+ <br>
+ The calibration can be verified (<span style="font-weight: bold;">-e</span>)
+ by printing a calibration test chart on <span
+ style="text-decoration: underline;">non-color managed</span>, <span
+ style="text-decoration: underline;"></span>but calibrated device,
+ the verification evaluating any discrepancy between the device
+ response achieved, and the device response expected. For a numerical
+ evaluation the verbose flag (<span style="font-weight: bold;">-v</span>)
+ should be used, and for a visual evaluation the plot flag (<span
+ style="font-weight: bold;">-p</span>) should be used.<br>
+ <br>
+ If there are several devices of the same or similar model, then one
+ device can be used to set the initial calibration target, and then
+ the other devices can be re-calibrated against the same .cal file,
+ to create matching responses. An alternative to creating an initial
+ linear target for calibration, is to use the <span
+ style="font-weight: bold;">-I</span> option with an initial
+ device, which sets the initial target to be that devices absolute
+ response. Naturally the corresponding calibration will be linear
+ (null). The calibration target can then be used to later return that
+ device to its initial response, or to make another similar device
+ have the same response. Note though, that bad things will happen if
+ the imitated devices response is non-monotonic, or if on
+ re-calibration the device is unable to reach the same density
+ levels.<br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ <br>
+ </body>
+</html>