RGBPrime2YPrimePbPrFunctor< T > Class Template Reference

Convert non-linear (gamma corrected) R'G'B' into Y'PbPr color difference components. More...

#include <vigra/colorconversions.hxx>

Public Types
typedef TinyVector< T, 3 >	argument_type

typedef NumericTraits< T > ::RealPromote	component_type

typedef TinyVector < component_type, 3 >	result_type

typedef TinyVector < component_type, 3 >	value_type

Public Member Functions
template<class V >
result_type	operator() (V const &rgb) const

	RGBPrime2YPrimePbPrFunctor ()

	RGBPrime2YPrimePbPrFunctor (component_type max)

Detailed Description

template<class T>
class vigra::RGBPrime2YPrimePbPrFunctor< T >

Convert non-linear (gamma corrected) R'G'B' into Y'PbPr color difference components.

#include <vigra/colorconversions.hxx>
Namespace: vigra

According to ITU-R Recommendation BT.601, the functor realizes the transformation

$\begin{array}{rcl} Y' & = & 0.299\enspace R / R_{max} + 0.587\enspace G / G_{max} + 0.114\enspace B / B_{max}\\ Pb & = & -0.1687358916\enspace R / R_{max} + 0.3312641084\enspace G / G_{max} + 0.5\enspace B / B_{max} \\ Pr & = & 0.5\enspace R / R_{max} + 0.4186875892\enspace G / G_{max} + 0.0813124108\enspace B / B_{max} \end{array}$

By default, $R_{max} = G_{max} = B_{max} = 255$ . This default can be overridden in the constructor. Y' represents the luminance ("brightness") of the color, and Pb and Pr are the blue (B'-Y') and red (R'-Y') color difference components. The transformation is scaled so that the following bounds apply: