1.4.3 The YIQ Color Model

This is used for color TV. Here $Y$ is the luminance (the only component necessary for B&W-TV). The conversion from RGB to YIQ is given by

$$\begin{pmatrix} Y \\ I \\ Q \end{pmatrix}= \begin{pmatrix} 0.30 &... ...& -0.52 & 0.31 \\ \end{pmatrix}\cdot \begin{pmatrix} R \\ G \\ B \end{pmatrix}$$

for standard NTSC RGB phosphor with chromaticity values

	R	G	B
x	0.67	0.21	0.14
y	0.33	0.71	0.08

The advantage of this model is that more bandwidth can be assigned to the Y-component (luminance) to which the human eye is more sensible than to color information. So for NTSC TV there are 4MHz assigned to $Y$, $1.5$MHz to $I$ and $0.6$MHz to $Q$.