25

The CIE system of colorimetry

The Commission Internationale de L’Éclairage (CIE) has defined a system that maps a spectral power distribution (SPD) of physics into a triple of numerical values – CIE XYZ tristimulus values – that form the mathematical coordinates of colour space. In this chapter, I describe the CIE system. In the following chapter, Colour science for video, I will explain how these XYZ tristimulus values are related to linear-light RGB values.

Colour coordinates are analogous to coordinates on a map (see Figure 25.1). Cartographers have different map projections for different functions: Some projections preserve areas, others show latitudes and longitudes as straight lines. No single map projection fills all the needs of all ...

Get Digital Video and HD, 2nd Edition now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.