computer graphics systems color principles
DESCRIPTION
Donald House Artist’s slides by Lynette House. Computer Graphics Systems Color principles. Color from Physics Viewpoint. Color from Physiological Viewpoint. 3 cone response curves Luminance efficiency. Color from Artist’s Viewpoint. Hue Saturation Value. Hue - Paint Mixing. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Computer Graphics Systems Color principles](https://reader035.vdocuments.us/reader035/viewer/2022062308/56812d92550346895d92ade2/html5/thumbnails/1.jpg)
Computer Graphics SystemsColor principles
Donald House
Artist’s slides by Lynette House
![Page 2: Computer Graphics Systems Color principles](https://reader035.vdocuments.us/reader035/viewer/2022062308/56812d92550346895d92ade2/html5/thumbnails/2.jpg)
Color from Physics Viewpoint
![Page 3: Computer Graphics Systems Color principles](https://reader035.vdocuments.us/reader035/viewer/2022062308/56812d92550346895d92ade2/html5/thumbnails/3.jpg)
Color from Physiological Viewpoint
3 cone response curves Luminance efficiency
![Page 4: Computer Graphics Systems Color principles](https://reader035.vdocuments.us/reader035/viewer/2022062308/56812d92550346895d92ade2/html5/thumbnails/4.jpg)
Color from Artist’s Viewpoint
• Hue• Saturation• Value
![Page 5: Computer Graphics Systems Color principles](https://reader035.vdocuments.us/reader035/viewer/2022062308/56812d92550346895d92ade2/html5/thumbnails/5.jpg)
Hue - Paint Mixing
• Physical mix of opaque paints
• Primary: RYB• Secondary: GOV• Neutral: R + Y + B
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Hue - Ink Mixing
• Subtractive mix of transparent inks
• Primary: CMY• Secondary: RGB• ~Black: C + M + Y• Actually use CMYK
to get true black
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Hue - Ink Mixing
Assumption: ink printed on pure white paper
CMY = White – RGB:C = 1 – R, M = 1 – G, Y = 1 – B
CMYK from CMY:K = min(C, M, Y)
C = C – K, M = M – K, Y = Y - K
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Hue - Light Mixing
• Additive mix of colored lights
• Primary - RGB• Secondary - CMY• White - R + G + B• Show demonstration
of optical mixing
![Page 9: Computer Graphics Systems Color principles](https://reader035.vdocuments.us/reader035/viewer/2022062308/56812d92550346895d92ade2/html5/thumbnails/9.jpg)
Saturation
• Purity of color
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Value
• Luminance• Dark to Light• Value range
– High key– Middle key– Low key
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RGB Color Wheel
• Warm/Cool• Complements • Split Complement• Analogous
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HSV Color Model
HSV is a projection of the RGB space
RGB cube HSV top view HSV cone
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HSV Color Model
Hue, an angular measure (0 - 360)
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HSV Color Model
Saturation, a fractional measure (0 - 1)
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HSV Color Model
Value, a fractional measure (0 - 1)
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CIE 1931 Study
Color Matching Experiment
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CIE Color Matching Functions
CIE RGB Matching Functions CIE XYZ Matching Functions
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RGB from Spectrum
RGB = x d
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XYZ from Spectrum
XYZ = x d
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CIE xyY color model is used to catalog colors:
x = X / (X + Y + Z)y = Y / (X + Y + Z)
Y = luminance
CIE xyY from CIE XYZ
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CIE xyY Color Cone
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CIE xyY Typical Display Gamut
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CIE Lu*v* and Lab Perceptually Uniform Spaces
Lu*v* rescales xyY Lab color opponents
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Color Picker
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