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SMPTE-240M Y'PbPr

This one of the developments of NTSC component coding, in which the B primary and white point were changed. The CRT gamma law is assumed to be 2.2. The white point is D65, chromaticity coordinates are:

    R:      xr=0.67     yr=0.33
    G:      xg=0.21     yg=0.71
    B:      xb=0.15     yb=0.06
    White:  xn=0.312713 yn=0.329016
The conversion equations for linear signals are:

    X = 0.567*R + 0.190*G + 0.193*B
    Y = 0.279*R + 0.643*G + 0.077*B
    Z = 0.000*R + 0.073*G + 1.016*B

    R = 2.042*X - 0.565*Y - 0.345*Z
    G =-0.894*X + 1.815*Y + 0.032*Z
    B = 0.064*X - 0.129*Y + 0.912*Z

The coding equations for non-linear signals are:

   Y'= 0.2122*R' + 0.7013*G' + 0.0865*B'
   Pb=-0.1162*R' - 0.3838*G' + 0.5000*B'
   Pr= 0.5000*R' - 0.4451*G' - 0.0549*B'

   R'= Y + 0.0000*Pb + 1.5756*Pr
   G'= Y - 0.2253*Pb + 0.5000*Pr
   B'= Y + 1.8270*Pb + 0.0000*Pr

The conversion equations relating SMPTE 240 RGB to EBU and 709 primaries are:

    R240= 0.7466*Re + 0.2534*Ge + 0.0000*Be
    G240= 0.0187*Re + 0..9813*Ge + 0.0000*Be    
    B240= 0.0185*Re + 0.0575*Ge + 0.9240*Be

    Re= 1.3481*R240 - 0.3481*G240 + 0.0000*B240
    Ge=-0.0257*R240 + 1.0257*G240 + 0.0000*B240
    Be=-0.0254*R240 - 0.0568*G240 + 1.0822*B240

and:

    R240= 0.7151*R709 + 0.2849*G709 + 0.0000*B709
    G240= 0.0179*R709 + 0.9821*G709 + 0.0000*B709
    B240= 0.0177*R709 + 0.0472*G709 + 0.9350*B709

    R709= 1.4086*R240 - 0.4086*G240 + 0.0000*B240
    G709=-0.0257*R240 + 1.0457*G240 + 0.0000*B240
    B709=-0.0254*R240 - 0.0440*G240 + 1.0695*B240