Questions on Color Model

1. State the difference between CMY and HSV color models.
The HSV (Hue,Saturation,Value) model is a color model which uses color descriptions that have a
more intuitive appeal to a user. To give a color specification, a user selects a spectral color and the
amounts of white and black that is to be added to obtain different shades, tint, and tones.
A color model defined with the primary colors cyan, magenta, and yellow is useful for describing
color output to hard-copy devices.

2. What are the subtractive colors?
RGB model is an additive system, the Cyan-Magenta-Yellow (CMY) model is a subtractive color
model. In a subtractive model, the more that an element is added, the more that it subtracts from
white. So, if none of these are present the result is white, and when all are fully present the result is
black.
3. Define - YIQ Color Model.
In the YIQ color model, luminance (brightness) information in contained in the Y parameter,
chromaticity information (hue and purity) is contained into the I and Q parameters.
A combination of red, green and blue intensities are chosen for the Y parameter to yield the
standard luminosity curve. Since Y contains the luminance information, black and white TV
monitors use only the Y signal.
4.What is a color model?
A color model is a method for explaining the properties or behavior of color within some particular
context. Example: XYZ model, RGB model.
5.How is the color of an object determined?
When white light is incident upon an object, some frequencies are reflected and some are absorbed
by the object. The combination of frequencies present in the reflected light determines what we
perceive as the color of the object.
6. Define -Primary Colors.
The two or three colors used to produce other colors in a color model are referred to as primary
colors.
7.State the use of chromaticity diagram.
Comparing color gamuts for different sets of primaries. Identifying complementary colors.
Determining dominant wavelength and purity of a given color.
8.What is Color Look up table?
In color displays, 24 bits per pixel are commonly used, where 8 bits represent 256 level for each
color. It is necessary to read 24- bit for each pixel from frame buffer. This is very time consuming.
To avoid this video controller uses look up table to store many entries to pixel values in RGB
format. This look up table is commonly known as colour table.
9.Explain in detail the basic illumination models.
10.Explain in detail on RGB color model. 
11.Explain in detail on YIQ color model. 
12.Explain in detail the HSV color model. 
13.Compare and contrast the RGB and CMY. 
 RGB is based on projecting. Red light plus Green light plus Blue light all projected together
create white. Black is encoded as the absence of any color.
 CMYK is based on ink. Superimpose Cyan ink plus Magenta ink plus Yellow ink, and you
get black, although this format also encodes Black (K) directly. White is encoded by the
absence of any color.
 Prism uses RGB internally. Exporting in RGB will give you results very close to what you
see on screen.
 Even though it uses one more number to encode a color, the CMYK scheme encodes a
smaller "color space" than does RGB.
 When a color is converted from RGB to CMYK, the appearance may change. Most
noticeably, bright colors in RGB will look duller and darker in CMYK
14.Explain in detail the conversion between HSV and RGB color models.