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DIFFUSED PROFILES:
-
Max: maximum of the profiles
-
Integral: area under the curve
1
st
reflection (SHINE) PROFILE:
-
Max: maximum of the shine peak
-
W
1/2
(deg) : width of the shine peak at Max/2
-
Integral: area under the shine peak
-
Shift to 0 (deg): angle between the center of the image (0 angle) and the Max of
the shine peak
2
nd
reflection (CHROMA) PROFILES:
-
W
1/2
(deg) : width of the chroma at Max/2
-
Max: maximum of the chroma profiles
-
Integral: area under the chroma profiles
-
Shift to 0 (deg): angle between the center of the image (0 angle) and the Max of
the chroma profile
-
Δ/shine (deg): angle between the max of the shine and the max of the chroma
7.5.
Step 4: Computation of Lusters
From the characterization of the specular and diffused profiles, we compute different
luster formulae.
In all the following formulae, S and D are the integral values from the specular and
diffused profiles respectively
.
Reich-Robbins
0
.
.
100
D
S
L
RR
TRI
0
.
.
)
(
.
100
ref
TRI
D
S
S
L
Where θ
ref
corresponds to the θ
0
obtained when measuring on the calibration sample.
Stamm
(
does not take the band width into account)
S
D
S
L
Stamm
.
100
Guiolet
(
does not take the band width into account)
D
S
L
Guiolet
.
100
