A overview of Color Models for Undergraduate Students

1. COLOR MODELS
Adri Jovin J.J.
Assistant Professor
Department of Information Technology
Sri Ramakrishna Institute of Technology
Coimbatore.

2. RGB Color Model
• Based on “tristimulus theory of vision”
– eyes perceive color through the stimulation of
three visual pigments in the cones of the retina
– peak sensitivity at wavelengths of about 630 nm
(red), 530 nm (green), and 450 nm (blue)
• Represented as a unit cube defined on R, G, B
axes
• Color Ck = RR + GG + BB
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3. RGB Color Model (Contd..)
"Cie Chart with sRGB gamut by spigget" by Spigget - Own work. Licensed
under Creative Commons Attribution-Share Alike 3.0 via Wikimedia
Commons -
http://commons.wikimedia.org/wiki/File:Cie_Chart_with_sRGB_gamut_
by_spigget.png#mediaviewer/File:Cie_Chart_with_sRGB_gamut_by_spig
get.png
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4. YIQ Color Model

R



R
G
0.299 0.587 0.144



0.299 0.587 0.144
0.596 0.275 0.321



Y
  





G



0.596 0.275 0.321




  



• National Television System Committee (NTSC)
color model for forming the composite video
signal
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









Y




B
I

Q
0.212 0.528 0.311










B
I
Q
0.212 0.528 0.311

5. YIQ Color Model (Contd…)
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"YIQ IQ plane" by Tonyle - Own work. Licensed under
Creative Commons Attribution-Share Alike 3.0 via
Wikimedia Commons -
http://commons.wikimedia.org/wiki/File:YIQ_IQ_plane.s
vg#mediaviewer/File:YIQ_IQ_plane.svg

6. CMY Color Model
• Defined with the primary colors cyan,
magenta, and yellow
• Useful for describing color output to hard-copy
devices
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7. CMY Color Model (Contd…)
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8. HSV Color Model
• Color parameters in this model are hue ( H ) ,
saturation( S ) and value( V )
• 3D representation is derived from RGB Cube.
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9. Reference
• Donald Hearn, Pauline Baker, Computer
Graphics – C Version, Second Edition, Pearson
Education, 2004.
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