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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Target Information 3 Format File (.ti3)</title>
<meta http-equiv="content-type" content="text/html;
charset=windows-1252">
<meta name="author" content="Graeme Gill">
</head>
<body>
<h2>Description of the .ti3 format</h2>
This is an ASCII text, <a href="File_Formats.html#CGATS">CGATS</a>,
Argyll specific format, used to hold device value and CIE/Spectral
value pairs, the raw information needed to create device profiles.
This file is typically created using the <a href="chartread.html">chartread</a>, <a
href="dispread.html"> dispread</a>, <a href="filmread.html">filmread</a>,
<a href="scanin.html"> scanin</a>, <a href="fakeread.html">
fakeread</a> or one of the conversion tools such as <a
href="cb2ti3.html">cb2ti3</a>, <a href="kodak2ti3.html">kodak2ti3</a>,
<a href="txt2ti3.html">txt2ti3</a>.<br>
<br>
While fully compatible with the CGATS.5 Data Exchange Format, the
particular required keywords and fields are unique to Argyll, hence
an Argyll specific file identifier <span style="font-weight: bold;">CTI3</span>
is used to avoid confusion with standard ANSI or CGATS files.<br>
<br>
The <span style="font-weight: bold;">.ti3</span> format changes
from time to time with new releases, to add new functionality, but
generally retains backwards compatibility. Note that in the
description below, the word "may" indicates an optional component,
while the word "shall" indicates a necessary component.<br>
<br>
Generally a .ti3 file contains only one table, the table containing
the colorimetric information. The exception is for a display in
which a set of RAMDAC values (most likely the result of display
calibration, or simply the video LUT (RAMDAC) values present in the
display when the test values were read) are recorded in a second
table.<br>
<br>
<br>
The first table contains the following:<br>
<br>
The file identifier (First 7 characters) shall be <span
style="font-weight: bold;">CTI3</span>.<br>
<br>
A <span style="font-weight: bold;">#</span> character introduces a
comment.<br>
<br>
<span style="font-weight: bold;"><span style="font-weight: bold;"><span
style="font-weight: bold;"></span></span></span>There may be <span
style="font-weight: bold;">DESCRIPTOR</span>, <span
style="font-weight: bold;">ORIGINATOR</span>, or <span
style="font-weight: bold;">CREATED</span> keywords and values (as
per CGATS).<br>
<br>
There shall be a <span style="font-weight: bold;">DEVICE_CLASS</span>
keyword that has a value of <span style="font-weight: bold;">"OUTPUT</span>",
"<span style="font-weight: bold;">DISPLAY</span>", <span
style="font-weight: bold;">"INPUT"</span> or <span
style="font-weight: bold;">"EMISINPUT"</span>.<br>
This indicates to the profile program what type of device the color
information is from. (An OUTPUT device is typically a printer. An
INPUT device is typically a Scanner or Camera with data from a
reflective reference chart. An EMISINPUT is a camera with emissive
rather than reflective reference data. ).<br>
<br>
An <span style="font-weight: bold;">"OUTPUT"</span> type device may
have a <span style="font-weight: bold;">TOTAL_INK_LIMIT</span>
keyword that has a numeric value indicating the maximum sum of the
device channel values as a percentage (T.A.C.), used in creating the
test chart. This will be used by the profiler as a value indicating
what the valid device gamut is, and what total ink limit should be
used in creating the profile tables.<br>
<br>
An <span style="font-weight: bold;">"OUTPUT"</span> type device may
have an <span style="font-weight: bold;">ILLUMINANT_WHITE_POINT_XYZ</span>
keyword that contains the XYZ of the illuminant used to compute the
CIE values from spectral reflectance or transmittance values. If
this tag is absent, the illuminant is assumes to be ICC standard
D50.<br>
<br>
A <span style="font-weight: bold;">"DISPLAY"</span> type device may
have a <span style="font-weight: bold;">LUMINANCE_XYZ_CDM2</span>
keyword that contains the absolute XYZ value of white in candelas
per meter squared, e.g. <span style="font-weight: bold;">"112.334770
119.657745 121.474236".<br>
<br>
</span>A display device may also have a <span style="font-weight:
bold;">NORMALIZED_TO_Y_100</span> keyword that must have a value
of "<span style="font-weight: bold;">NO</span>" or "<span
style="font-weight: bold;">YES</span>", to indicate whether the
CIE values have been normalised so that the largest has a Y value of
100. If this is a display type device and there is no <span
style="font-weight: bold;">NORMALIZED_TO_Y_100</span> keyword,
then it can be assumed that the value <span style="font-weight:
bold;">are</span> normalized to Y = 100. If the values are
normalized to Y = 100, then the absolute values can be restored by
multiplying the XYZ values by the <span style="font-weight: bold;">LUMINANCE_XYZ_CDM2</span>
Y value and dividing by 100.<br>
<br>
There may be a keyword <span style="font-weight: bold;">TARGET_INSTRUMENT</span>
which will identify the instrument used to read the test values.
This is used by the profiling program to determine the spectral
characteristics of the instrument illuminant if Fluorescent Whitener
Compensation is desired. The value shall be one of:<br>
<blockquote> <b>"X-Rite DTP20"</b><br>
<b>"X-Rite DTP22"</b><br>
<b>"X-Rite DTP41"</b><br>
<b>"X-Rite DTP51"</b><br>
<b>"X-Rite DTP92"</b><br>
<b>"X-Rite DTP94"</b><br>
<b>"GretagMacbeth Spectrolino"</b><br>
<b>"GretagMacbeth SpectroScan"</b><br>
<b>"GretagMacbeth SpectroScanT"</b><br>
<b>"Spectrocam"</b><br>
<b>"GretagMacbeth i1 Display 1"</b><br>
<b>"GretagMacbeth i1 Display 2"</b><br>
<b>"X-Rite i1 DisplayPro, ColorMunki Display"</b><br>
<b>"GretagMacbeth i1 Monitor"</b><br>
<b>"GretagMacbeth i1 Pro"</b><br>
<b>"X-Rite i1 Pro 2"</b><br>
<b>"X-Rite ColorMunki"</b><br>
<b>"Colorimtre HCFR"</b><br>
<b>"ColorVision Spyder1"</b><br>
<b>"ColorVision Spyder2"</b><br>
<b>"Datacolor Spyder3"</b><br>
<b>"Datacolor Spyder4"</b><br>
<b>"Datacolor Spyder5"</b><br>
<b>"GretagMacbeth Huey"</b><br>
<b>"ColorMunki Smile"</b><br>
<b>"JETI specbos 1201"</b><br>
<b>"JETI specbos"</b><br>
<b>"Klein K-10"</b><br>
<b>"Image Engineering EX1"</b><br>
</blockquote>
All instruments except the Spectrocam are assumed to have an "A"
type illuminant (incandescent lamp of 2850 degrees Kelvin.)<br>
<br>
There may be a <span style="font-weight: bold;">INSTRUMENT_TYPE_SPECTRAL</span>
keyword that must have a value of "<span style="font-weight: bold;">NO</span>"
or "<span style="font-weight: bold;">YES</span>", to indicate
whether the instrument is based on spectral measurement or not.<br>
<br>
There may be a <span style="font-weight: bold;">DISPLAY_TYPE_REFRESH</span>
keyword that must have a value of "<span style="font-weight: bold;">NO</span>"
or "<span style="font-weight: bold;">YES</span>", to indicate
whether the instrument was used in a display refresh mode during
measurement.<br>
<br>
There may be a <b>DEVCALSTD</b> keyword that must have a value of <b>"XRDI"</b>
or <b>"GMDI"</b> or <b>"XRGA"</b>, to indicate which X-Rite
calibration standard the data has been measured.<br>
<br>
There may be a <b>INSTRUMENT_FILTER</b> keyword that must have a
value of <b>"POLARIZED"</b> or <b>"D65"</b> or <b>"UVCUT"</b> to
indicate whay if any filter was present during measurement.<br>
<br>
There may be keywords with associated values <span
style="font-weight: bold;">SINGLE_DIM_STEPS</span>, <span
style="font-weight: bold;">COMP_GREY_STEPS</span>, <span
style="font-weight: bold;">MULTI_DIM_STEPS</span> or <span
style="font-weight: bold;">FULL_SPREAD_PATCHES</span>, that
document the composition of the test chart patches.<br>
<br>
There shall be a keyword <span style="font-weight: bold;">COLOR_REP</span>
that has a value that indicates what colorspaces the test values
connect. The colorspaces shall be encoded with one or two
letters per component, and the two color spaces shall then separated
by an <span style="font-weight: bold;"><span style="font-weight:
bold;">_</span></span> (underscore) character. For output and
display devices, the device space shall come first, followed by the
PCS space. For an input device, the PCS shall come first, followed
by the device space. The PCS space shall be either XYZ space,
indicated by <span style="font-weight: bold;">XYZ</span>, or D50
while point L*a*b* space, indicated by <span style="font-weight:
bold;">LAB</span>. The device spaces shall use the following
letter encoding:<br>
<br>
<span style="font-weight: bold;"><span style="font-weight: bold;"></span></span>
Cyan
C<br>
Magenta
M<br>
Yellow
Y<br>
Black
K<br>
Orange
O<br>
Red
R<br>
Green
G<br>
Blue
B<br>
White
W<br>
Light Cyan
c<br>
Light
Magenta
m<br>
Light
Yellow
y<br>
Light
Black
k<br>
Medium Cyan
2c<br>
Medium Magenta
2m<br>
Medium Yellow
2y<br>
Medium Black
2k<br>
Light Light Black 1k<br>
<br>
There may be an a previx <span style="font-weight: bold;">i</span>
preceeding the device space letter encoding, indicating that
although the space appears to be an additive space, it is in fact a
subtractive device.<br>
<br>
Typical values might be: "<span style="font-weight: bold;">RGB_XYZ</span>"
or "<span style="font-weight: bold;">RGB_LAB</span>" for an RGB
display, "<span style="font-weight: bold;">iRGB_XYZ</span>" or "<span
style="font-weight: bold;">iRGB_LAB</span>" for an RGB printer, "<span
style="font-weight: bold;">CMYK_XYZ</span>" for a printer, "<span
style="font-weight: bold;">XYZ_RGB"</span> for an RGB scanner.<br>
<br>
If spectral values are going to be included in the file, the
following keywords and values shall be used:<br>
<br>
<span style="font-weight: bold;"> SPECTRAL_BANDS</span> shall
contain the number of spectral bands in the readings, e.g. <span
style="font-weight: bold;">"36"</span>.<br>
<span style="font-weight: bold;">SPECTRAL_START_NM</span>
shall contain the wavelength in nanometers of the first band, e.g. <span
style="font-weight: bold;"><span style="font-weight: bold;"><span
style="font-weight: bold;">"380.0"</span></span></span>.<br>
<span style="font-weight: bold;">SPECTRAL_END_NM</span>
shall contain the wavelength in nanometers of the last band, e.g. <span
style="font-weight: bold;">"730.0"</span>.<br>
<br>
The <span style="font-weight: bold;">NUMBER_OF_FIELDS</span>
keyword shall have a value that indicates the number of fields in
each data set, e.g. <span style="font-weight: bold;">43</span> (as
per CGATS).<br>
<br>
The start of the declaration of the fields shall be marked by the <span
style="font-weight: bold;">BEGIN_DATA_FORMAT</span> keyword (as
per CGATS).<br>
Then shall follow the names of the fields. Standard CGATS field
names such as:<br>
<br>
<span style="font-weight: bold;"> SAMPLE_ID</span>, <span
style="font-weight: bold;">RGB_R</span>, <span
style="font-weight: bold;">RGB_G</span>, <span
style="font-weight: bold;">RGB_B</span>, <span
style="font-weight: bold;">CMYK_C</span>, <span
style="font-weight: bold;">CMYK_M</span>, <span
style="font-weight: bold;">CMYK_Y</span>, <span
style="font-weight: bold;">CMYK_K</span>, <span
style="font-weight: bold;">XYZ_X</span>, <span
style="font-weight: bold;">XYZ_Y</span>, <span
style="font-weight: bold;">XYZ_Z</span>, <span
style="font-weight: bold;">LAB_L</span>, <span
style="font-weight: bold;">LAB_A</span> or <span
style="font-weight: bold;">LAB_B</span><br>
<br>
shall be used where appropriate. Other device fields shall use the
appropriate pattern, e.g. <span style="font-weight: bold;">CMYKOG_G</span>
etc. Spectral band values shall be named <span style="font-weight:
bold;">SPEC_XXX</span>, where <span style="font-weight: bold;">XXX</span>
is the nearest integer values of the number of nanometers of the
band.<br>
<br>
Optional patch location information shall use the <span
style="font-weight: bold;">SAMPLE_LOC</span> field and shall be of
quoted string type.<br>
<br>
The definition of the fields shall be terminated by the <span
style="font-weight: bold;">END_DATA_FORMAT</span> keyword (as per
CGATS).<br>
<br>
The <span style="font-weight: bold;">NUMBER_OF_SETS</span> keyword
shall have a value that indicates the number of sets of data, e.g. <span
style="font-weight: bold;">1000</span> (as per CGATS).<br>
<br>
The start of the values of the data sets shall be marked by the <span
style="font-weight: bold;">BEGIN_DATA</span> keyword (as per
CGATS).<br>
<br>
Each set of data shall be on one line, and shall be separated by
white space. All device values shall be percentages (e.g. values
from 0.0 to 100.0). XYZ values shall normalized to a Y value of
100.0. L*a*b* values will have their normal range (L* 0.0 to 100.0,
a* and b* typically -128.0 to 128.0).<br>
<br>
The end of the values of the data sets shall be marked by the <span
style="font-weight: bold;">END_DATA</span> keyword (as per CGATS).<br>
<br>
Generally any other keywords and values will be ignored.<br>
<br>
If a second table is present, and it is a display RAMDAC
calibration, printers or input devices per channel calibration
curves, and will be of the <a href="cal_format.html">CAL file
format</a>..<br>
<br>
</body>
</html>
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