1. A method of augmented reality comprising the steps of: providing a book having blue or green pages; capturing a video image of a scene comprising the book; for each pixel in at least a sub-region of the captured video image, classifying the pixel as either a skin or non-skin pixel responsive to whether the colour of the pixel exceeds a predetermined threshold ratio of red to blue or green; generating a mask based upon the classification of the pixels of the captured video; generating an image layer comprising a virtual entity to superpose on the book in the captured video image of the scene comprising the book; and generating an augmented image of the scene comprising the book by superposing the image layer on the captured video image of the scene comprising the book; in which the pixels of the image layer that correspond to skin pixels in the mask are masked out to retain skin pixels in the augmented image.