A Study on the Simulation of Map Colors for the Color Vision Impaired*, ** Hyu-seok Shin*** Hyeon-jeong Cho**** Key-ho Park*****. GIS ArcGIS ArcObject. 216 99%. CIE xy (RGB, CIE xyy, HSV).., CIE XYZ, CIE xy,, srgb Abstract : The purpose of this paper is to examine the methods of simulating map color appearance for the color vision impaired and then to develop the visual impairment simulator. The simulator is developed using ArcObject components of ArcGIS products. The simulator validity was verified, with approximately 99 percent accuracy, by a series of experiments on color vision impaired subjects where colors selected among 216 web safe colors were compared before and after simulation. To enhance its utility, the simulator displays the CIE xyy coordinates of the colors before and after simulation and also presents the color confusion lines for each type of color vision impairment. The simulator also records the values of color components(rgb, CIE xyy, HSV) to ensure the objectivity of these color analyses. The outcomes of this paper can serve as a basic tool for map color researches on color vision impairment. Key Words : simulation of color vision impairment, CIE XYZ color system, CIE xy chromatic diagram, confusion lines, srgb color space.. ( ) (geographic features) * 2009 ( ) (KRF-2009-327-B00849). ** 2010 11 (, 2010). *** (Ph.D. Candidate, Department of Geography, Seoul National University, kevin52@snu.ac.kr) ***** (Ph.D. Candidate, Department of Geography, Seoul National University, hjcho94@snu.ac.kr) ***** (Professor, Department of Geography, Seoul National University, khp@snu.ac.kr)
(Mersey, 1990). (, 2006;, 2009). (graphicacy) 1)., 4.16-5.9%, 0.31-0.4% (, 1980; Kim HB et al,. 1989), 4%~8% (Wyszecki and Stiles 1982:464, Birch, J. 1993, Sharpe et al. 1999). 2)..,..., 3.. Esri ArcGIS ArcObject VBA. ArcGIS.. Red, Green, Blue RGB, ( : Color Gamut).. srgb.. CIE xyy x, y 2 CIE xy (Confusion lines). 596
( : ), ( : )., L (long wavelength 564nm : ), M (middle wavelength 533nm : ), S (short wavelength 437nm : )..,.. 1. L R(Red), M G(Green), S B(Blue). 3., L(Red) 564nm M(Green) ( 1 ) L(Red) ( 1 ). 2 2. 3 (three elements of color) (source of light), (object), (visual system)..,. (color system). 1931 (CIE:Commission internationale de l éclairage) CIE XYZ RGB (, 2006). CIE XYZ CIE xy. CIE xy CIE XYZ X, Y, Z ( 597
(a) (b) (c) (a) (b) (c) 2(a) ) 1 3 ( 2(b) ) x,y ( 2(c) ) 3). Y., CIE xy CIE XYZ 3. Y = Y... (1) x = X/(X + Y + Z) y = Y/(X + Y + Z) (Confusion point) (Wyszecki and Stiles, 1982).. (dichromat) 4),,. Pitt(1935) Scheibner and Boynton(1967), Nimeroff(1970), Smith and Pokorny(1972, 1975), Walraven(1974), Scheibner and Paulus(1978) (Oleari et al. 1996 ). 0.01 10 598
CIE xy CIE xy x y 0.75 0.25 1.4-0.4 0.18 0. 3 Travis(1991) ( 1 ) CIE xy. 4.. L, M, S (spectral sensitivity) 3 LMS. LMS L M S 3 RGB. LMS L M S. Meyer and Greenberg(1988) Brettel et al.(1997). Meyer and Greenberg(1988) LMS L M S CIE XYZ (dichromat). Meyer and Greenberg(1988). Brettel et al.(1997) 2 L M S. L M S, (neutrals) 5), 575nm 475nm, 660nm 485nm. 3. Brettel et al.(1997) (Vienot et al., 1999; Mollon and Regan, 2001; Kovalev, 2006; Jenny and Kelso, 2007; Linhares et al., 2008). Vischek, Colorfield Digital Media Colorfield Insight, Fujitsu Color Doctor. Brettel et al.(1997) (Wachtler et 599
al. 2004) Brettel et al.(1997). Brettel et al.(1997). Q LMS Q RGB LMS, RGB.. Q LMS (L Q, M Q, S Q ) (2) Stockman et al.(1993). _ L Q = k j Q (l)l (l)dl, M Q = k j Q (l)m _ (l)dl, M Q = k j Q (l)s _ (l)dl,...(2), _ j Q (l) : (spectral power distribution) l (l), m _ (l), _ s (l) : (spectral weighting function) Q (P R, P G, P B ) (3) R Q, G Q, B Q 0 1. Q = R Q P R + G Q P G + B Q P B...(3) LMS Q P i LMS (4) (5) T, V Q (6). L Q M Q S Q L i M i S i Q = ( ) P i = ( ) L R L G L B M R M G M B S R S G S B (i = R, G, B)...(4) R Q G Q B Q T = [ ] V = ( )...(5) Q = TV, V = T _1 Q...(6) Q Q (6) V. Q Q 5. LMS Q 2 Q (Q p: 1, Q d: 2 ). Microsoft VBA(Visual Basic for Applications) Esri ArcGIS(9.x). 6. ArcGIS RGB LMS RGB. 2 LMS 2 R G B.,,, 4. 600
RGB to XYZ var_r = ( R / 255) var_g = (G / 255) var_b = (B / 255) if (var_r > 0.04045) var_r = ((var_r + 0.055) / 1.055) ^ 2.4 else var_r = var_r / 12.92 if (var_g > 0.04045) var_g = ((var_g + 0.055) / 1.055) ^ 2.4 else var_g = var_g / 12.92 if (var_b > 0.04045) var_b = ((var_b + 0.055) / 1.055) ^ 2.4 else var_b = var_b / 12.92 var_r = var_r * 100 var_g = var_g * 100 var_b = var_b * 100 X = var_r * 0.4124 + var_g * 0.3576 + var_b * 0.1805 Y = var_r * 0.2126 + var_g * 0.7152 + var_b * 0.0722 Z = var_r * 0.0193 + var_g * 0.1192 + var_b * 0.9505 XYZ to xyy Y = Y x = X / (X + Y + Z) y = Y / (X + Y + Z) RGB to XYZ XYZ to xyy (gamma) 6). CIE xyy 2 CIE xy (Confusion lines) RGB HSV(Hue, Saturation, Value). RGB CIE xyy, RGB XYZ II-2 (1) ( 2 ). 7. 601
Gretag Macbeth Eye-One Display 2 srgb. SyncMaster 177T WinFast PX9600(NVIDIA). : (%) 1 ( ) 2 ( ) 3 ( ) 2 ( ) 3 ( ) 3 14 0 0 17( 85) 1 2 0 0 3( 15) 4(20) 16(80) 0 0 20(100). (20 ~31 ) 20 3. 2 16 ( 80%) 17 3. Farnsworth Dichotomous Test(D-15). 1:1 216. 216. 216 ( 8-a ) ( 8-b ). 2 2 ( ) 1 (1~2 ) 1 1 (a) (b). 1 1 ( ). 2 2 ( ). 99%. 67%. Brettel et al.(1997). 7). Brettel et al.(1997) RGB LMS 602
. 67% 93%~97%... 2005. 9 1 3 RGB CIE xy. 9-a 1... CIE xy, 9-b 1. 8). 3 9-a 1. - -. 9-b 3..,. (Olson and Brewer, 1997).. 10 CIE xy ( 10-a ) ( 10-b )... RGB,, HSV. CIE xyy Y. 11-a CIE xy Y. (5 ) (1, 2, 3, 4 ) (6, 7, 8, 9 603
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(a) (b) ). 11-a. 1 11-b 11-b (Hue: 50~51). (5 ) (1 ). (, : 0.1, : 0.07). 11-c 11-c 3 3.. 4, 5 11-c. 605
...., (RGB, CIE xyy, HSV)..., (color tolerance).,. CIE xyy CIE Lab CIE Lch.,.....,.. (, )... 1) (1998). 2) 2008 220 330, 2 7 5 4. 606
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