C. OLEARI and R. REVERBERI
Tristimulus-space transformations and luminance-coefficient computation in RGB colour mixing
Received: 18 May 1999
Mathematics Subject Classification: 92J30 - 68U10 - 92C05
Abstract: Luminace is a quantity that contributes to the colour specification, either directly or indirectly. Its simplest definition is given in the XYZ system, proposed as a standard by the Commission Internationale de l'Éclairage (CIE). However usually, in the informatics systems with cathodic-ray-tube, plasma or liquid-crystal displays, the colour is specified in the RGB reference frame. This reference frame is obtained by proper linear transformations, that are summarised in this paper with the aim to compute the luminance by means of a simple operation. Here, the CIE 1931 Standard Observer is considered, but this treatment holds for CIE 1964 Standard Observer and the Judd-Vos one, too.