# Argyll CMS documentation index (V1.8.3)

Date: 26th October 2015
Author: Graeme Gill

## Introduction

ArgyllCMS is an ICC compatible color management system, available as Open Source. It supports accurate ICC profile creation for scanners, cameras and film recorders, and calibration and profiling of displays and RGB & CMYK printers. Device Link can be created with a wide variety of advanced options, including specialized Video calibration standards and 3dLuts. Spectral sample data is supported, allowing a selection of illuminants observer types, and paper fluorescent whitener additive compensation. Profiles can also incorporate source specific gamut mappings for perceptual and saturation intents. Gamut mapping and profile linking uses the CIECAM02 appearance model, a unique gamut mapping algorithm, and a wide selection of rendering intents. It also includes code for the fastest portable 8 bit raster color conversion engine available anywhere, as well as support for fast, fully accurate 16 bit conversion. Device color gamuts can also be viewed and compared with a modern Web browser using X3DOM . Comprehensive documentation is provided for each major tool, and a general guide to using the tools for typical color management tasks is also available. A mailing list provides support for more advanced usage.

This is Version 1.8.3, a bug fix update to V1.8.2. The first public release of icclib was in November 1998, and of Argyll was in October 2000. Code development commenced in 1995. See Changes Summary for an overview of changes since the last release. Changes between revisions is detailed in the log.txt file that accompanies the source code.

The latest source code is available from here.

Please note that instruments are being driven by ArgyllCMS drivers, and that any problems or queries regarding instrument
operation should first be directed to the Argyll's author(s) or the Argyll mailing list, and not to any other party.

## An Introduction to Color Management

A great introduction for non technical people is Steve Upton's The Color of Toast.

I present here a more technical but concise discussion of what color management is, and why we need it, together with a brief overview of the ICC profile format.

## Operating Environments

##

Argyll is known to compile and run in at least the following environments:

1) MSWindows XP system using Microsoft VC++ 6.0 compiler
2) MSWindows XP system using Microsoft VC++ 8.0 Express compiler + Platform SDK Feb. 2003
3) MSWindows XP system using Microsoft VC++ 9.0 Express compiler + Platform SDK Feb. 2003
4) MSWindows XP system using Microsoft VC++ 10.0 Express compiler + Platform SDK Feb. 2003
5) MSWindows XP system using Microsoft VC++ 11.0 Express compiler
6) MSWindows XP system using the MingW port of the GCC compiler
7) Linux on Fedora Core 8, 32 bit using gcc
8) Linux on Fedora Core 8, 64 bit using gcc
9) Apple OS X 10.3 PPC using GCC
10) Apple OS X 10.4, 10.5, 10.6 Intel using GCC
11) Apple OS X10.7 Intel using Clang
Additionally it is also known to run on:
MSWindows 2000, Vista & Windows 7 32 bit.
MSWindows Vista 64bit, Windows 7, 8, 8.1 64 bit.
Linux Ubuntu 7.10
Linux Kubuntu 7.10
Linux Mandriva 2008.0
Linux OpenSuSE 10.3
Linux Whitebox 4.2/2

but may well compile and run correctly in many more than this, including OS X 10.8, 10.9 and 10.10 & MSWin 10.

This is a command line terminal only environment. Those unfamiliar with command line environments should consult an appropriate tutorial for their environment if they are interested in using this software. See the listing of tutorials below.
The following color measuring instruments are directly supported:
JETI:
specbos 1211 & 1201 - Tele-Spectro-Radiometer
Image Engineering:
EX1 - Tele-Spectro-Radiometer
Klein:
K10-A - Display Colorimeter. Reported also to work with the K-1, K-8 and K-10.
X-Rite:
DTP20 "Pulse" - "swipe" type reflective spectrometer, that can be used untethered.
DTP22 Digital Swatchbook - spot type reflective spectrometer.
DTP41 - spot and strip reading reflective spectrometer.
DTP41T - spot and strip reading reflective/transmissive spectrometer.
DTP51 - strip reading reflective colorimeter.
DTP92 - CRT display colorimeter.
DTP94 "Optix XR" or "Optix XR2" or "Optix Pro"- display colorimeter.
ColorMunki Design or Photo - spot and "swipe" reflective/emissive spectrometer (UV cut only).
ColorMunki Create or Smile - display colorimeter. (Similar to an Eye-One Display 2)
Lenovo W - built in laptop Huey display colorimeter.
Eye-One Display 3 - Xrite i1 DisplayPro and ColorMunki Display
[ The OEM i1Display Pro, NEC SpectraSensor Pro,
Quato Silver Haze 3 OEM and HP DreamColor i1d3 are also reported to work.]
Eye-One Pro2 - spot and "swipe" reflective/emissive spectrometer.
Gretag-Macbeth (now X-Rite):
Spectrolino - spot reflective/emissive spectrometer.
SpectroScan - spot reflective/emissive, XY table reflective spectrometer .
SpectroScanT - spot reflective/emissive/transmissive, XY table reflective spectrometer.
Eye-One Pro "EFI ES-1000" - spot and "swipe" reflective/emissive spectrometer.
Eye-One Monitor - spot and "swipe" emissive spectrometer.
Eye-One Display 1 or 2 or LT - display colorimeter.
HP DreamColor or APS - display colorimeter. (Treated as a Eye-One Display 2)
CalMAN X2 - display colorimeter. (Treated as a Eye-One Display 2)
Huey - display colorimeter.
Sequel imaging (Now X-Rite):
MonacoOPTIX - display colorimeter (Treated as an Eye-One Display 1)
[The Sequel Chroma 4 may also work.]
Lacie Blue Eye: - see Eye-One Display
DataColor ColorVision:
Spyder 2 - display colorimeter (Note that the user must supply firmware)
[The Spyder 1 has also been reported as working, but this has not been confirmed.]
Spyder 3 - display colorimeter.
Spyder 4 - display colorimeter (Note that the user must supply calibration data)
Spyder 5 - display colorimeter (Note that the user must supply calibration data)
Other:
Colorimètre HCFR - display colorimeter
ColorHug - display colorimeter
Palette/SwatchMate Cube - reflective colorimeter
See Operation of particular instruments for more instrument specific detail.
Other instruments can be supported indirectly, since patch result files created by other packages can be imported into Argyll.
Please note the installation instructions for each platform - they contain important information for getting your instruments working.

If you've decided to buy a color instrument because Argyll supports it, please let the dealer and manufacturer know that "You bought it because Argyll CMS supports it" - thanks.

Please note that instruments are being driven by ArgyllCMS drivers, and that any problems or queries regarding instrument
operation should be directed to the Argyll's author(s) or the Argyll mailing list, and not to any other party.

There is a list of contributed ccmx (Colorimeter Correction Matrix) files for some display/colorimeter combinations.

## Copyright, Licensing & Trade Mark:

Most of the source code and provided executable files are copyrighted works, licensed under the Affero GNU Version 3 license, and therefore they (or works derived from them) can't be copied, sold or made available to users interacting with them remotely through a computer network, without providing the source code. Nothing other than your agreement and compliance with the Affero GNU License grants you permission to use, modify or distribute ArgyllCMS source code, executables or its derivative works. You could be sued for copyright infringement if you use or distribute ArgyllCMS without a valid license. The Affero GNU license prohibits extending these tools (i.e. by combining them with other programs or scripts that make use of, depend on, or work with the ArgyllCMS code) and distributing them, unless all the elements of the extensions are also made available under a GPL compatible license. It is permissible to provide ArgyllCMS tools with other non GPL components if the elements of the package are not related, such that the packaging is mere aggregation. For all the gory details, please read the accompanying license.

Note that unlike many commercial ICC profiling tools, the profiles created using ArgyllCMS, are not subject to any claims or restrictions of ArgyllCMS's author(s), but are assumed to be the copyright property of the person who gathers the characterization data, and causes the profiles to be created.

The ArgyllCMS is Copyright 1995 - 2015 Graeme W. Gill, and is made available under the terms of the Affero GNU General Public License Version 3, as detailed in the License.txt file. Documentation is licensed under the terms of the GNU Free Documentation License, Version 1.3. The author asserts his moral rights over this material in relationship to the attribution and integrity of these works. In particular, if these works are modified in a way that materially changes their functionality, then the modified works should be renamed in a way that clearly distinguishes them from "Argyll" or "ArgyllCMS" so that the effects of such changes do not reflect on the original works integrity or the original authors reputation. A subset of files (those that are related to the color instrument drivers, and are collected together into the instlib.zip archive by the spectro/instlib.ksh script + xicc/ccmx.h and xicc/ccmx.c) are licensed under the General Public License Version 2 or later, as detailed in the License2.txt file.

Portions of the ColorHug instrument library (spectro/colorhug.[ch]) are Copyright 2011, Richard Hughes, and is licensed under the General Public License Version 2 or later, as detailed in the License2.txt file.

The tool spectro/spec2cie.c is Copyright 2005 Gerhard Fuernkranz, and is made available under the terms of the GNU General Public License Version 2 or later, and is licensed here under the Version 3 license, as detailed in the License3.txt file.

The Win32 USB library libusb-win32 kernel drivers are included in this distribution in the usb/driver and usb/bin directories, and are copyright Stephan Meyer and Travis Robinson, and are licensed under the GNU Version 2 or later (the drivers, services, installer). See usb/driver/License.txt, libusbw/COPYING_LGPL.txt and libusbw/COPYING_GPL.txt for details. Additional terms noted on the website are "This license combination explicitly allows the use of this library in commercial, non-Open-Source applications."

The icc library in icc/, the CGATS library in cgats/, the jcnf library in jcnf/, the files spectro/xdg_bds.*, spectro/aglob.* and the ucmm library in ucmm/ are Copyright 1995 - 2015 Graeme W. Gill, and available according to the "MIT" license granted in the icc/License.txt and cgats/License.txt files, and the licenses at the top of ucmm/ucmm.c and jcnf/jcnf.c.

The yajl library in jcnf/yajl is Copyright (c) 2007-2014, Lloyd Hilaiel <me@lloyd.io> and is used under an ISC License granted in the yajl/COPYING files. The yajl library has been repackaged and modified slightly to adds some features and for packaging and build convenience.

The TIFF library included in this distribution for convenience, has its own copyright and license detailed in tiff/COPYRIGHT (an "MIT"/"BSD" like license).

The Independent JPEG Group's JPEG library included in this distribution for convenience, has its own copyright and license detailed in jpg/README (an "MIT"/"BSD" like license). Executables that include JPEG format support are based in part on the work of the Independent JPEG Group.

xicc/iccjpeg.h and xicc/iccjpeg.c are from lcms and they are Copyright (c) 1998-2010 Marti Maria Saguer and is licensed under an "MIT"/"BSD" like license. See the top of the iccjpeg.c file for the detailed copyright and licensing conditions.

The mongoose web server software is Copyright (c) 2004-2011 Sergey Lyubka, and is licensed under an "MIT" license.

The axTLS library is Copyright (c) 2008, Cameron Rich, and the license is detailed in ccast/axTLS/LICENSE file (an "MIT"/"BSD" like license).
It is not used for any security sensitive purpose, but is used purely to communicate with the ChromeCast.

The X3DOM x3dom.css and x3dom.js files are Copyright (C) 2009 X3DOM and licensed dual "MIT" and "GPL" license. See plot/X3DOM_LICENSE.txt.

"ArgyllCMS" is a trade mark. It is permissible to refer to copies or derivatives of this software as being the same as ArgyllCMS if they are materially unchanged, and retain all the functionality provided by the software made available at www.argyllcms.com. Modified versions of this software that are materially changed or have missing functionality must be clearly marked as such, so as not to to be confused with ArgyllCMS.

## What sort of project is this ? (re: contributions)

This is essentially my private project, that I've made available under GNU licensing conditions. Because I license my code under other licenses as well, there is a limit to what I will accept in the way of code contributions back into this project. For me to accept contributions into the distribution, it either has to a non-core (side) project, or has to be offered to me with copyright conditions that are compatible with my other uses (i.e.. a "BSD" like license, or assigning or licensing the copyright to me), or has to be so trivial (say a one line bug fix), that it can't be the subject of copyright.
Of course there is nothing to stop someone setting up a real free software, community project based on the GNU licensed code made available here, that would be able to take GNU licensed contributions from everyone and would essentially be a "fork" of this code base.

# Compiling

How to build the software from the source if you want to.
Note that you don't need to do this if you are using one of the binary installations.

# Installing

Important notes on installing the binary software on various platforms.

## Graphic User Interfaces

ArgyllCMS does not directly support a graphic user interface, but several people have written GUI based front ends for it. A popular front end that supports display calibration and profiling is dispcalGUI by Florian Höch. Others can be found with a suitable search.

## Main Tools and the command line

These are all command line ("DOS" shell) tools, and each tool require appropriate options to be set, followed by filename arguments. Sometimes the filenames will have to include the usual extensions, sometimes they are implicit. To get a brief listing of the possible arguments and usage of any of the tools, run it with just an "-?" argument, i.e. targen -? (or some other unrecognized flag, if the "?" character is treated specially in your shell, i.e. try "--" on OS X zsh).
Note that in general the arguments consist of possible flags or options followed by file name arguments. All arguments need to be separated by whitespace. (If you need to specify a string with embedded white space, double quote the string). A flag consists of a dash attached to a single letter, the letter identifying the flag, and is usually case sensitive. An option is a flag that has an associated parameter or parameters. The parameter can be separated from the flag by white space, or may come directly after the flag. So if a tool has a usage that looks like this:
tool -?
usage: tool [options] infile outfile
-v Verbose mode
-d n Choose a depth 0-4
-r Use a random depth
-f [nn] Use full range. nn optional range 0 - 100.
-M Manual
infile Input file
outfile Output file
then there are 5 flags/options, and two filename arguments. Notice that square braces [] denote optional items. The first flag/option is a flag. The second is an option that has a numerical argument in the range 0 to 4. The third is a flag. the fourth is an option with an optional argument. The fourth is a flag. The flags and options can generally be in any order, but must be before the file name arguments. (For a few special tools you actually specify a sequence of flags and files where the flags apply just to the following file.) So example invocations may look like:
tool -v testin testout
tool -d3 -M testin1 testout2
tool -f infile outfile
tool -f 45 infile outfile
tool -d 3 -f67 infile outfile

In order to make use of the tools, it is necessary to keep track of where various files are, and what they are called. There are many possible ways of doing this. One way is to put each source profile and all its associated files (test charts, spectrometer values etc.) in one set of directories for each source profile type. Similarly the device profiles could be stored in a hierarchy of directories ordered by device type, media, resolution, device mode etc. Naturally you will want to set your $PATH so that you can run the tools from whichever directory you are in, as well as specify any necessary directory paths for file arguments so that the tools are able to open them.

Note that there are two ways the Argyll tools deal with filename extensions. In one you supply the extension (ie. you supply the whole file name), so the extension is up to you. In the other (used where one name is used for input and output files, or where there are multiple output files), the program adds the extension. In the documentation this should be indicated by calling it a "base name".

For more information on using a command line environments, consult an appropriate tutorial:

MS Windows :
<http://www.bleepingcomputer.com/tutorials/tutorial76.html>
<http://www.pcstats.com/articleview.cfm?articleid=1723&page=1>
<http://www.voidspace.org.uk/python/articles/command_line.shtml>
To find more: <http://www.google.com/search?hl=en&q=windows+command+prompt+tutorial>
OS X:
<http://www.osxfaq.com/Tutorials/LearningCenter/>
<http://www.atomiclearning.com/macosxterminalx.shtml>
<http://www.oreillynet.com/pub/a/mac/2001/12/14/terminal_one.html>
To find more: <http://www.google.com/search?hl=en&q=OS+X+shell+tutorial>
Linux:
<http://www.linuxcommand.org/index.php>
<http://www.tuxfiles.org/linuxhelp/shell.html>
<http://www.ee.surrey.ac.uk/Teaching/Unix/>
To find more: <http://www.google.com/search?q=linux+command+line+shell+tutorial>

Note that since OS X is based on UNIX, there is much in common between the OS X and Linux command line environments, and many of the UNIX tutorials may be useful:

<http://www.rain.org/~mkummel/unix.html>

## Tutorial: Typical usage scenarios and examples

A guided tour of the major tools, applied to typical CMS jobs, such as calibrating displays, creating device profiles, calibrating printers, linking profiles, and converting color spaces of raster files.
Although it is is a couple of years old now, this tutorial may also be of interest.

### Topical Discussions

Discussions about particular topics:
About Fluorescent Whitening Agent compensation
Operation of particular instruments
About ICC profiles and Gamut Mapping
About display monitor settings and targets
About display "Gamma"
What's the difference between Calibration and Characterization ?
Why doesn't my Colorimeter work well on my Wide Gamut display ?
My blacks get crushed on my display - why ? How do I fix it ?
How can I have confidence in the i1pro Driver ?
Does the i1pro High Resolution mode improve accuracy ?
Evaluating input targets
ArgyllCMS's Absolute to media Relative Transform Space matrix ('arts') ICC tag

## Flow diagram of Major Tools:

## Main Tools by category:

### Calibrating devices

dispcal Adjust, calibrate and profile a display.
printcal Create a printer calibration .cal file from a .ti3 data file.

### Creating test targets for profiling or print calibration

targen Generate a profiling test target values .ti1 file.
filmtarg Create film recorder TIFF files from Argyll .ti1 file.
printtarg Create a PS, EPS or TIFF file containing test patch values, ready for printing.

### Obtaining test results for profiling or print calibration

chartread Read a test chart using an instrument to create a .ti3 data file.
dispread Test and read colorimetric values from a display
filmread Read film colorimetric values using a SpectroScanT (Deprecated ?)
scanin Convert a TIFF image of a test chart into .ti3 device values.
illumread Use an instrument to measure an illuminant spectrum, and estimate its UV content.
fakeread Fake the reading of a device using an ICC or MPP profile.
synthread Fake the reading of a device using a synthetic device model.
cb2ti3 Convert Colorblind format CMY/RGB test chart into Argyll .ti3 CGATS format.
kodak2ti3 Convert Kodak Colorflow format CMYK test chart into Argyll .ti3 CGATS format.
txt2ti3 Convert Gretag/Logo/X-Rite/Barbieri or other format RGB or CMYK test chart results into Argyll .ti3 CGATS format.
ls2ti3 Convert LightSpace format RGB .bcs test chart results into Argyll .ti3 CGATS format.
fakeCMY Create a fake Argyll .ti3 CMY data file from a CMYK profile, as a basis of creating a CMY to CMYK separation
average Average or Merge two or more measurement data files, or average patches within a single file.

### Creating Device Profiles

colprof Create an ICC profile from the .ti3 test data.
mppprof Create a Model Printer Profile (MPP) from the .ti3 test data.
revfix Regenerate a device profiles B2A table data by inverting the A2B table.

### Creating Device Link Profiles

collink Link two device ICC profiles to create a device link profile.

### Converting colors or applying print calibration

cctiff Color convert a TIFF or JPEG file using a sequence of ICC device, device link, abstract profiles and calibration files.
applycal Apply calibration curves to an ICC profile.
icclu Lookup individual color values through any ICC profile table.
xicclu Lookup individual color values forward or inverted though an ICC profile or CAL table.
mpplu Lookup individual color values though an MPP profile. Also create MPP gamut files/views.
greytiff Convert a TIFF file to monochrome using an ICC device profile

### Color Tweaking tools

refine Creates an abstract profile from two chart readings, useful for refining proofing profiles.

### Creating gamut views

iccgamut Create a gamut file or VRML file of the color gamut of an ICC profile.
tiffgamut Create a gamut file or VRML file of the color gamut of a TIFF or JPEG image.
viewgam Convert one or more gamuts into a VRML 3D visualization file. Compute an intersection.

### Diagnostic and test tools

iccdump Dump the contents of an ICC profile as text.
profcheck Check an ICC profile against .ti3 test chart data, create pruned .ti3 file.
invprofcheck Check ICC forward against inverse lookup.
splitsti3 Split a CGATS file (ie. a .ti3) into two parts randomly to verify profiling.
timage Create TIFF test images.
mppcheck Check an MPP profile against .ti3 test chart data.
spotread Use an instrument to read a single spot color value.
colverify Verify matching of CIE in two CGATS/.ti3 files (also view differences as VRML)
synthcal Create a synthetic input, display or output calibration (.cal)file.

### Other Tools

ccxxmake Use a Spectrometer to create a Colorimeter Correction Matrix (CCMX) or a Colorimeter Calibration Spectral Set (CCSS) for a particular display.
extracticc Extract an embedded ICC profile from a TIFF or JPEG file.
extractttag Extract a text tag (ie. CGATS .ti3 data or CAL) from an ICC profile.
dispwin Install or uninstall display profile, set display calibration from profile or .cal file, test displace and dispwin access to a display.
oeminst Install Instrument manufacturers files for the Spyder 2, EDR or CCSS calibration files for i1d3 or Spyder 4 or 5, CCMX files for colorimeters.
specplot Plot a spectrum (.sp, .cmf, .ccss) and calculate CCT and VCT.
spec2cie Convert reflective spectral .ti3 readings into CIE XYZ and D50 L*a*b* readings. Apply FWA, plot spectrums.

## Main Tools Alphabetic Listing:

applycal Apply calibration curves to an ICC profile.
average Average or Merge two or more measurement data files, or average patches within a single file.
cb2ti3 Convert Colorblind format CMY/RGB test chart into Argyll .ti3 CGATS format.
cctiff Color convert a TIFF or JPEG file using a sequence of ICC device, device link, abstract profiles and calibration files.
ccxxmake Use a Spectrometer to create a Colorimeter Correction Matrix (CCMX) or a Colorimeter Calibration Spectral Set (CCSS) for a particular display.
chartread Read a test chart using an instrument to create a .ti3 data file.
collink Link two device ICC profiles to create a device link profile.
colprof Create an ICC profile from the .ti3 test data.
colverify Verify matching of CIE in two CGATS/.ti3 files (also view differences as VRML)
dispcal Adjust, calibrate and profile a display.
dispread Test and read colorimetric values from a display
dispwin Install or uninstall display profile, set display calibration from profile or .cal file, test displace and dispwin access to a display.
extracticc Extract an embedded ICC profile from a TIFF or JPEG file.
extractttag Extract a text tag (ie. CGATS .ti3 data or CAL) from an ICC profile.
fakeCMY Create a fake Argyll .ti3 CMY data file from a CMYK profile, as a basis of creating a CMY to CMYK separation
fakeread Fake the reading of a device using an ICC or MPP profile.
filmread Read film colorimetric values using a SpectroScanT (Deprecated ?)
filmtarg Create film recorder TIFF files from Argyll .ti1 file.
greytiff Convert a TIFF file to monochrome using an ICC device profile
iccdump Dump the contents of an ICC profile as text.
iccgamut Create a gamut file or VRML file of the color gamut of an ICC profile.
icclu Lookup individual color values through any ICC profile table.
illumread Use an instrument to measure an illuminant spectrum, and estimate its UV content.
invprofcheck Check ICC forward against inverse lookup.
kodak2ti3 Convert Kodak Colorflow format CMYK test chart into Argyll .ti3 CGATS format.
ls2ti3 Convert LightSpace format RGB .bcs test chart results into Argyll .ti3 CGATS format.
mppcheck Check an MPP profile against .ti3 test chart data.
mpplu Lookup individual color values though an MPP profile. Also create MPP gamut files/views.
mppprof Create a Model Printer Profile (MPP) from the .ti3 test data.
oeminst Install Instrument manufacturers files for the Spyder 2, EDR or CCSS calibration files for i1d3 or Spyder 4 or 5, CCMX files for colorimeters.
printcal Create a printer calibration .cal file from a .ti3 data file.
printtarg Create a PS, EPS or TIFF file containing test patch values, ready for printing.
profcheck Check an ICC profile against .ti3 test chart data, create pruned .ti3 file.
refine Creates an abstract profile from two chart readings, useful for refining proofing profiles.
revfix Regenerate a device profiles B2A table data by inverting the A2B table.
scanin Convert a TIFF image of a test chart into .ti3 device values.
spec2cie Convert reflective spectral .ti3 readings into CIE XYZ and D50 L*a*b* readings. Apply FWA, plot spectrums.
specplot Plot a spectrum (.sp, .cmf, .ccss) and calculate CCT and VCT.
splitsti3 Split a CGATS file (ie. a .ti3) into two parts randomly to verify profiling.
spotread Use an instrument to read a single spot color value.
synthcal Create a synthetic input, display or output calibration (.cal)file.
synthread Fake the reading of a device using a synthetic device model.
targen Generate a profiling test target values .ti1 file.
tiffgamut Create a gamut file or VRML file of the color gamut of a TIFF or JPEG image.
timage Create TIFF test images.
txt2ti3 Convert Gretag/Logo/X-Rite/Barbieri or other format RGB or CMYK test chart results into Argyll .ti3 CGATS format.
viewgam Convert one or more gamuts into a VRML 3D visualization file. Compute an intersection.
xicclu Lookup individual color values forward or inverted though an ICC profile or CAL table.

## Environment Variables

Performance/memory tuning hints, plus tweaks for scipting.

## Performance Tuning

Performance hints.

## Overview

Overview of the software and its aims and functionality.

## Limitations

Limitations of the current functionality.

## Organization

How directories are organized, what they contain.

## Source

Any detailed documentation on how the software works, or what algorithms it is based on. (Very incomplete.)

## Minor Tools

A very brief description of minor tools and test harnesses.

## File formats that Argyll uses

Argyll uses a number of file formats for its operation, some that are external standards, and some that are unique to Argyll.
.ti1 Device test values
.ti2 Device test values & chart layout
.ti3 Device test values & CIE tristimulus/spectral results Format details.
.cal Device calibration information. Format details.
.cht Test chart recognition template. Format details.
.gam 3D gamut surface description
.sp Illuminant spectral description
.cmf Color Matching Functions
.ccmx Colorimeter Correction Matrix
.ccss Colorimeter Calibration Spectral Set
CGATS Standard text based data exchange format
ICC International Color Consortium profile format
MPP Model device profile format
TIFF Tag Image File Format raster files.
JPEG Joint Photographic Experts Group, JPEG File Interchange Format raster files.
ucmm Unix micro Color Management Module convention and configuration file format and Profile Locations.
VRML Virtual Reality Modelling Language 3D file format.
X3D Open standards file format to represent 3D scenes using XML.
X3DOM Open-source framework and runtime for 3D graphics on the Web.

## Errors, Corrections and Omissions:

If you notice any errors, corrections needed or omissions in the current documentation, please contact the author.