21 Perceptual relation bettween shadow, reflectance and luminance under aambiguous illuminations. 1100302 2010 3 1
2 1 ( ) 2 ( ) i
Abstract Perceptual relation bettween shadow, reflectance and luminance under aambiguous illuminations. Syoichi Shinoda In this research we tested how the surface reflectance and the illuminant affect the perception of shadow. And also we tested how the shadow affects our perception of the reflectance and the brightness of object s surface. We conducted two types of experiments to reveal above things. The first experiment, which examined how the perception affects what people think is the shadow of a different intensity of light spotlighting the floor with different reflectivity. As a result, perception seems to shadow, otherwise the results are in contrast with the case decided by the people. The strength of the shadows and sounds that people are not simply determined by brightness, surface color (reflectivity) went on to say that determine perceived light intensity and spotlighting. The second experiments, and investigated whether any influence on the perception of color and brightness of illumination light spots on the surface of the shadow. As a result, by that body and its shadow, Compared to the object and its shadow when there is no perception of light is spotlighting, The results obtained may be stronger than the brightness constancy. The study, perception of sounds and shadows of people are not only determined by a simple brightness, the color (reflectivity) of the surface have decided on the perception of light intensity and spotlighting. Also, some suggesting that it is possible that the ii
perception of brightness by the shadow. key words Shadow, Spotlight, Reflectance, Contrast iii
1 1 1.1...................................... 1 1.2...................................... 2 2 3 2.1................................ 3 2.2................................... 4 3 1 5 3.1................................... 5 3.1.1................................. 5 3.2...................................... 6 3.3................................... 7 3.4.................................... 7 3.5...................................... 8 3.5.1 S.S........................... 8 3.5.2 K.I........................... 9 3.5.3 Q.Q.......................... 9 3.5.4 S.M.......................... 10 3.5.5 R.T.......................... 10 3.6...................................... 11 3.6.1....................... 11 3.6.2..................... 16 4 2 17 iv
4.1................................... 17 4.1.1......................... 17 4.2...................................... 18 4.3................................... 19 4.4.................................... 20 4.5...................................... 20 4.5.1 Q.Q.......................... 21 4.5.2 S.M.......................... 22 4.5.3 R.T.......................... 23 4.5.4 R.T.......................... 24 4.6...................................... 25 5 27 28 29 v
2.1.................................... 3 2.2 1..................... 4 3.1 1..................... 6 3.2 S.S 1.......................... 8 3.3 K.I 1.......................... 9 3.4 Q.Q 1.......................... 9 3.5 S.M 1.......................... 10 3.6 R.T 1.......................... 10 3.7............ 11 3.8...................... 12 3.9.......................... 13 3.10 ( R.T)...................................... 15 3.11............ 16 4.1 2.................... 18 4.2 Q.Q 2 (Whiteness)................... 21 4.3 Q.Q 2 (Brightness).................. 21 4.4 S.M 2 (Whiteness)................... 22 4.5 S.M 2 (Brightness)................... 22 4.6 R.T 2 (Whiteness)................... 23 4.7 R.T 2 (Brightness)................... 23 4.8 T.N 2 (Whiteness)................... 24 vi
4.9 T.N 2 (Brightness)................... 24 4.10 None Object-Shadow................... 25 vii
3.1 1................................. 6 3.2.................... 11 3.3 α β...... 14 4.1 2 BG1.............................. 19 4.2 2 BG2.............................. 19 viii
1 1.1, [1] ( ) ( ) ( ),,,. Cast Shadow [2][3] 1 2 1
1.2 1.2 2 2
2 2.1., (Epson EMP-74 LCD projector). 2.1 2.1 2 3
2.2 2.2 1 2.2 2.2 3 0 Project Area RGB (0,0,0) 4
3 1 1 1 3.1 1, (Method of adjustment) 3.1.1 (Method of average error) (Method of reproduction)., ( ).,.,,.,,.,,, [4]. 1 RGB 5
3.2 3.2 1 (Object) 1cm Object 6cm 14cm 6cm 8cm 2cm 3.1 3.1 1 9.5%(C1) 88.3%(C2) 2 3 ( S1 S2 S3) 3.1 3.1 (cd/m 2 ) S1 S2 S3 C1 1.44 8.89 13.02 C2 13.36 82.63 121.0 S3C1 S1C2 6
3.3 3.3 1 3.1 12 6 3.4 1 5 S.S ( ) K.I ( ) Q.Q ( ) S.M ( ) R.T ( ) 7
3.5 3.5 1 12 UpLim(Upper Limit) LowLim(Lower Limit) App(Appropriate).B 9.5%(Black).W 88.3%(White) 3.5.1 S.S S.S 1 3.2 88.3% 3.2 S.S 1 8
3.5 3.5.2 K.I K.I 1 3.3 3.3 K.I 1 3.5.3 Q.Q Q.Q 1 3.4 3.4 Q.Q 1 9
3.5 3.5.4 S.M S.M 1 3.5 3.5 S.M 1 3.5.5 R.T R.T 1 3.6 3.6 R.T 1 10
3.6 3.6 3.6.1 ( 3.7(a) ) ( 3.7(b) ) 3.7 (a) (b) (a) S.M (b) Q.Q 3.2 3.2 S.S C2 I.K S.M R.T Q.Q 11
3.6 RGB (0,0,0) 3.8 1 3.8 ( Q.Q) E All E I = αe All + β (3.1) α β 12
3.6 R L c L s L c = E All R (3.2) L s = E I R = (αe All + β)r (3.3) 3.9 3.9 L s L c Contrast = L s L c (3.4) 3.4 3.2 3.3 Contrast = β R L c + α (3.5) 13
3.6 3.5 3.5 α β α β 3.3 3.3 α β α β S.S C2 Observer C1(9.5%) C2(88.3%) R.T α 0.3 0 β 2 1.5 Q.Q α 0.3 0 β 5.8 7 I.K α 0.13 0.05 β 0 0 S.M α 0.25 0.2 β 0 0 S.S α 0.07 - β 0.09 - R.T 3.10 3.3 α β α R.T Q.Q α β α C1 C2 0.3 0 I.K S.M S.M α C1 C2 0.25 0.2 R.T Q.Q α C1 C2 14
3.6 3.10 3.5 α β 3.3 α β C1 α C2 α α 0 β 0 I.K S.M C1 C2 β 0 15
3.6 3.6.2 2 S3C1 S1C2( 3.1 ) S3C1 S1C2 2 ( ) 3.11 3.11 UpLim LowLim AproShadow 16
4 2 2 1 4.1 2 (Magnitude estimastion) 4.1.1 ( ) 100 70 S R R = ks n (4.1) R S n [5] 17
4.2 2 100 0 (Whiteness) (Brightness) 4.2 2 3 L R T 4.1 4.1 2 Bar Bar L Bar 2 T (None) 1 Object (Object-Shadow) 2 RGB T 6 (C1 C6) 5 (S1 S5) 2 (BG1 BG2) 60 BG1 S1C6 59 4.1 4.2 Object-Shadow 18
4.3 S1 Object-Shadow BG1 23 BG2 24 47 4.1 BG1 (cd/m 2 ) Object-Shadow S1 (None 29 Object-Shadow 23 ) S1 S2 S3 S4 S5 C1 0.110 0.115 0.440 0.980 - C2 0.118 0.226 1.710 5.877 15.790 C3 0.264 0.683 4.380 15.073 44.053 C4 0.430 0.054 8.283 29.670 79.850 C5 0.638 1.786 12.733 44.577 133.043 C6 0.828 2.180 10.810 54.910 163.737 4.2 BG2 (cd/m 2 ) Object-Shadow S1 (None 30 Object-Shadow 24 ) S1 S2 S3 S4 S5 C1 0.115 0.343 0.513 1.374 2.432 C2 0.298 1.100 2.047 5.833 14.773 C3 0.796 2.610 5.087 16.547 36.507 C4 1.406 5.160 10.153 28.917 66.330 C5 2.067 7.863 15.597 44.503 114.070 C6 2.687 10.043 19.883 56.167 144.053 4.3 2?? L R T None (Whiteness) 4.1 4.2 59 19
4.4 (Brightness) Object-Shadow None (Whiteness) (Brightness) 6 4.4 2 4 Q.Q ( ) S.M ( ) R.T ( ) T.N ( ) 4.5 2 6 T 20
4.5 4.5.1 Q.Q Q.Q 2 (Whiteness) 4.2 (Brightness) 4.3 4.2 Q.Q 2 (Whiteness) 4.3 Q.Q 2 (Brightness) 21
4.5 4.5.2 S.M S.M 2 (Whiteness) 4.4 (Brightness) 4.5 4.4 S.M 2 (Whiteness) 4.5 S.M 2 (Brightness) 22
4.5 4.5.3 R.T R.T 2 (Whiteness) 4.6 (Brightness) 4.7 4.6 R.T 2 (Whiteness) 4.7 R.T 2 (Brightness) 23
4.5 4.5.4 R.T R.T 2 (Whiteness) 4.8 (Brightness) 4.9 4.8 T.N 2 (Whiteness) 4.9 T.N 2 (Brightness) 24
4.6 4.6 None T S.M R.T NoneBG1 R.T ( 4.6NoneBG1 ) None Object-Shadow T 4.10 4.10 R.T 2 None Object-Shadow None Object-Shadow Britghtness Object Object 25
4.6 Object T Object 26
5 1 2 None Object-Shadow Object 27
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[1] CD 2000 [2] Vol.55 No.11 pp.1492-1498 2001 [3] 12 2000 [4] pp.22-23 2004 [5] pp.55-56 2004 29