summaryrefslogtreecommitdiff
path: root/doc/spec2cie.html
blob: 79119486b2f19d0f2f5e6859f83cf135db2103ee (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <title>fakeread</title>
    <meta http-equiv="content-type" content="text/html;
      charset=windows-1252">
    <meta name="author" content="Graeme Gill">
  </head>
  <body>
    <h2><b>spectro/</b><span style="text-decoration: underline;"></span>spec2cie</h2>
    <h3>Summary</h3>
    Convert reflective spectral <a href="File_Formats.html#.ti3">.ti3</a>
    readings into CIE XYZ and D50 L*a*b* readings. Apply FWA, plot
    spectrums.<br>
    <h3>Usage</h3>
    <tt><small>spec2cie [options] <span style="font-style: italic;">input.ti3



          output.ti3<br>
          &nbsp;</span></small></tt><tt><small>-v
        &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
        Verbose mode</small></tt><br>
    <tt><small><small>&nbsp;<a href="spec2cie.html#I">-I <i>illum</i></a>&nbsp;&nbsp;



          &nbsp;&nbsp; Override actual instrument illuminant in .ti3
          file:<br>
          &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
          &nbsp; &nbsp;&nbsp; A, C, D50, D50M2, D65, F5, F8, F10 or
          file.sp<br>
          &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;



          (only used in conjunction with <span style="font-weight:
            bold;">-f</span>)<br>
        </small></small></tt><tt><small><small>&nbsp;<a
            href="colprof.html#f">-f [<i>illum</i>]</a> &nbsp;&nbsp; Use
          Fluorescent Whitening Agent compensation [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>
        </small></small></tt><tt><small><small><small>&nbsp;<a
              href="spec2cie.html#i">-i <i>illum</i></a>&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; A, C, D50 (def.), D50M2, D65, F5,
            F8, F10 or file.sp<br>
            &nbsp;</small></small><a href="#o">-o <i>observ</i></a>&nbsp;



        &nbsp;&nbsp; Choose CIE Observer for spectral data:<br>
        &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&nbsp;
&nbsp;&nbsp;



        1931_2 </small></tt><tt><small> (def.)</small></tt><tt><small>,
        1964_10, S&amp;B 1955_2, shaw, J&amp;V 1978_2 or file.cmf<br>
        &nbsp;<a href="#p">-n</a>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Don't
output



        spectral values<br>
      </small></tt><tt><small>&nbsp;<a href="#p">-p</a>
        &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
        Plot each values spectrum</small></tt><tt><br>
    </tt><tt> </tt><tt><small>&nbsp;<span style="font-style: italic;">input.ti3</span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Measurement



        file<br>
        &nbsp;<span style="font-style: italic;">output.ti3</span>&nbsp;&nbsp;&nbsp;&nbsp;



        Converted measurement file</small></tt><br>
    <h3>Comments</h3>
    This program takes the (usually reflective) spectral data in a .ti3
    file, converts them to XYZ and D50 L*a*b* and fills the XYZ_[XYZ]
    and LAB_[LAB] columns in the output .ti3 file. If the columns
    XYZ_[XYZ] and/or LAB_[LAB] are missing in the input file, they are
    added to the output file.<br>
    <br>
    If FWA correction is applied, then the spectra saved will be FWA
    corrected, as well as the XYZ and D50 L*a*b* values.<br>
    <br>
    All other columns are copied from the input to the output .ti3 file.<br>
    <br>
    Setting an actual instrument/simulated instrument/CIE illuminant
    only has an effect for reflective/transmissive spectra. Emissive
    spectra don't have an illuminant, and will simply be converted to
    XYZ using the given observer. <br>
    <br>
    <br>
    <a name="I"></a>The <b>-I</b> parameter allows specifying a an
    illumination spectrum for the actual instrument illuminant,
    overriding that computed from the type of instrument (recorded in
    the .ti3 file). This is rarely used. This parameter is can only be
    used in combination with the <span style="font-weight: bold;">-f</span>
    flag. 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. Illuminant details are:<br>
    <br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; A&nbsp;&nbsp; CIE
    tungsten filament lamp 2848K<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; D50 CIE daylight 5000K<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; D65 CIE daylight 6500K<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; F5&nbsp; CIE Fluorescent
    6350K, CRI 72<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; F8&nbsp; CIE Fluorescent
    5000K, CRI 95<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; F10 CIE Fluorescent
    5000K, CRI 81<br>
    <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, 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="colprof.html#f">colprof -f</a> for a fuller explanation. <br>
    <br>
    <a name="i"></a>The <b>-i</b> parameter 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>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; A&nbsp;&nbsp; CIE
    tungsten filament lamp 2848K<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; D50 CIE daylight 5000K<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; D65 CIE daylight 6500K<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; F5&nbsp; CIE Fluorescent
    6350K, CRI 72<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; F8&nbsp; CIE Fluorescent
    5000K, CRI 95<br>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; F10 CIE Fluorescent
    5000K, CRI 81<br>
    <br>
    Custom illuminants are most often used when a&nbsp; viewing booth or
    other known viewing conditions is going to be used to view results.
    Other illuminant reference files could be created using a suitable
    measuring instrument such as a spectrolino, or an eyeone using <a
      href="spotread.html">spotread</a>, although such instruments do
    not themselves provide the necessary response down to Ultra Violet
    that is needed for accurate operation of Fluorescent Whitening Agent
    compensation. The best way of measuring a custom illuminant is to
    use <a href="illumread.html">illumread</a>, since it uses a special
    method to estimate the illuminant UV in a way that complements FWA
    compensation. (See the discussion above for the <b>-f</b> flag).<br>
    <br>
    Note that if an illuminant other than D50 is chosen, the resulting
    ICC profile will not be standard, and may not work perfectly with
    other profiles that that use&nbsp; the standard ICC 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>&nbsp; 1931_2</b> selects the standard CIE 1931 2 degree observer
    (the default).<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>
    or a .cmf file can be provided as an argument.<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.<br>
    <br>
    <br>
    <a name="n"></a>The <span style="font-weight: bold;">-n</span> flag
    disables the output of the spectral values. If just the XYZ and D50
    L*a*b* values are needed, this makes for a smaller, easier to read
    file.<br>
    <br>
    <a name="p"></a>The <span style="font-weight: bold;">-p</span> flag
    causes each spectrum to be plotted. If FWA compensation is used,
    then the before/after compensation spectruma will be shown.<br>
    <br>
    <br>
    <br>
    <br>
    <br>
    <br>
  </body>
</html>