This book is aimed at those using colour image processing or researching new applications or techniques of colour image processing. It has been clear for some time that there is a need for a text dedicated to colour. We foresee a great increase in the use of colour over the coming years, both in research and in industrial and commercial applications. We are sure this book will prove a useful reference text on the subject for practicing engineers and scientists, for researchers, and for students at doctoral and, perhaps masters, level. It is not intended as an introductory text on image processing, rather it assumes that the reader is already familiar with basic image processing concepts such as image representation in digital form, linear and non-linear filtering, trans forms, edge detection and segmentation, and so on, and has some experience with using, at the least, monochrome equipment. There are many books cov ering these topics and some of them are referenced in the text, where appro priate. The book covers a restricted, but nevertheless, a very important, subset of image processing concerned with natural colour (that is colour as per ceived by the human visual system). This is an important field because it shares much technology and basic theory with colour television and video equipment, the market for which is worldwide and very large; and with the growing field of multimedia, including the use of colour images on the Inter net.