Color in Image and Video

Abstract

In this chapter, color and color spaces are introduced; without excellent color, images and video would look unacceptable. But how is this accomplished in the real world, light bounces off surfaces and the resulting spectrum enter the eye. Retinal sensors then take over, forming a trio of signal values in (combinations of) red, green, and blue. But if a camera is used instead, then the question arises of just what values should properly be stored, with the objective of eventually perceiving the right colors when the image is viewed on a display. Given that the display itself has spectral characteristics, and again the eye’s sensors come into play, what is the pipeline for producing pleasing-looking images, when starting off from camera images? This chapter sets out the basics of Color Science, which is the science of human vision. It then goes on to consider image formation in the eye and in cameras, arriving at the question of specifications for color display screens. The mismatch between human vision and display systems brings up the notion of out-of-gamut colors and white point correction, as well as perceptual color. Finally, other color-coordinate schemes are introduced, including color in printers and video.