Digital Image Processing Color Model Dr.Ji Zhen Faculty of Information Engineering, SZU 2003.01 1
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400-700 nm ( ) CIE " " 380 780 nm " " 400 nm ( ) 700 nm ( ) 4
( ) A: B: C: D: E: 5
Hue (Saturation) (Brightness) ( ) " " 6
Original Image Increase Decrease Brightness 7
Contrast( ) Original Image Increase Contrast Decrease Contrast 8
A: B: C: 9
" " 5,000 4,000 6,500 6,500 10
( 5,000 ) 11
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1.RGB (CRT, ) 2.CMY ( ) 3.HSV ( ) 4.CIE 14
1. Tri-Original Color 400-500 nm ( ) 500-600 nm 600-700 nm RGB 100% 0% 15
B b=(0,0,1) c=(0,1,1) m=(1,0,1) w=(1,1,1) k=(0,0,0) G g=(0,1,0) R r=(1,0,0) y=(1,1,0) 16
1. 100% ( ) 17
2.CMYK (C) (M) (Y) (K) CMYK 18
2. CMYK 19
3.HSV 1854 (H.Grassmann) Hue (Saturation ) (Brightness) (Hue) (Saturation) (Brightness, Value) CRT 20
4.CIE CIE XYZ CIE L*a*b 21
4.CIE -CIE XYZ CIE XYZ 1931 CIE XYZ x y CIE XYZ 22
4.CIE -CIE XYZ X,Y,Z, x=x/(x+y+z), y=y/(x+y+z), z=z/(x+y+z),x+y+z=1 400nm 700nm 2 2 23
4.CIE -CIE XYZ C 1/3 P x=0.48, y=0.40. C P Q 590nm P 590nm Q P C 66 66 24
(CIE ) A: B: C: D: RGB CMY CMY RGB CMYK CMYK 25
4.CIE -CIE L*a*b L: a: b: CIE L*a*b CIE XYZ 1931 CIE 1976 CIE L*a*b L*a*b L( ) a( ) b( ) XYZ CIE L*a*b* CIE L*a*b* L a b CIE L*a*b CIE L*a*b* 26
4.CIE -CIE L*a*b ( ) Photoshop Lab (L) 0 100 a - b - +120-120 Lab Photo CD PostScript(R) Level 2 Level 3 Lab PostScript CMYK Lab Photoshop 27
Photoshop Photoshop Photoshop Photoshop HSB RGB CMYK CIE L*a*b* Photoshop 28
HSB HSB 0 360 0% 100% 0% 100% 0 29
RGB Photoshop RGB RGB RGB 0 255 R 246 G 20 B 50 255 0 RGB R G B 256 1670 30
RGB ( ) RGB RGB 24bit RGB CMYK CMYK RGB CMYK 31
CMYK RGB CMYK CMYK (C) (M) (Y) (K) K B 32
CMYK ( ) (CMY) (RGB) Photoshop CMYK 2% 93% 90% 0% CMYK 0% CMYK RGB CMYK RGB CMYK RGB CMYK CMYK CMYK 33
(C) (M) (Y) 100% (K) CMYK RGB CMYK ( ) 34
GCR( ) CMY 35
Indexed Indexed 8bit 256 Photoshop Photoshop 36
Hue Photoshop Brightness RGB= (43,23,33) HSB=(330,46,17) RGB= (207,112,159) HSB=(330,46,81) Saturation 37
Photoshop = RGB + + R G B 38