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Image processing[edit]




Previous conditions[edit]

In the following formulas must be complied this supposition:

R, G, B, Y \in \left[ 0, 1 \right], \quad I \in \left[-0.5957, 0.5957\right], \quad Q \in \left[-0.5226, 0.5226\right]

From RGB to YIQ[edit]

\begin{bmatrix} Y \\ I \\ Q \end{bmatrix}
  0.299    &  0.587    &  0.114 \\
  0.595716 & -0.274453 & -0.321263 \\
  0.211456 & -0.522591 &  0.311135

From YIQ to RGB[edit]

  1 &  0.9563 &  0.6210 \\
  1 & -0.2721 & -0.6474 \\
  1 & -1.1070 &  1.7046

Two things to note regarding the RGB transformation matrix:

  • The top row is identical to that of the YUV color space
  • \begin{bmatrix} R \\ G \\ B \end{bmatrix} = \begin{bmatrix} 1 \\ 1 \\ 1 \end{bmatrix} \implies \begin{bmatrix} Y \\ I \\ Q \end{bmatrix} = \begin{bmatrix} 1 \\ 0 \\ 0 \end{bmatrix}

FCC version of NTSC standard[edit]


\left \{
\right .

in matrix notation, that equation system is written as:

\begin{bmatrix} E_Y^\prime \\ E_I^\prime \\ E_Q^\prime \end{bmatrix}
  0,30    &  0,59    &   0,11 \\
  0,599   & -0,2773  &  -0,3217 \\
  0,213   & -0,5251 &    0,3121
\begin{bmatrix} E_R^\prime \\ E_G^\prime \\ E_B^\prime \end{bmatrix}


  • E_Y^\prime is the gamma-corrected voltage of luma.
  • E_R^\prime, E_G^\prime and E_B^\prime are the gamma-corrected voltages corresponding to red, green, and blue signals.
  • E_I^\prime and  E_Q^\prime are the amplitudes of the orthogonal components of the chrominance signal.



The equivalent bandwidth assigned prior to modulation to the color difference signals EQ′ and EI′ are as follows:

Q-channel bandwidth: At 400 kHz less than 2 dB down. At 500 kHz less than 6 dB down. At 600 kHz at least 6 dB down.

I-channel bandwidth: At 1.3 MHz less than 2 dB down. At 3.6 MHz at least 20 dB down.


  1. ^ "TV transmission standards". U.S. Government Printing Office. 2013. p. 210. Retrieved 11 July 2014. 

External links[edit]