An image display apparatus and method is disclosed that can prevent shot-sneaking
of an image displayed by a projector apparatus. The projector apparatus embeds
a display image portion in which the same color is represented with another color
space of R, Cy, and B by color space conversion as a shot-sneaking preventing image
portion into an original image as a display image for which a color space of R,
G, and B is used to reproduce a color. The shot-sneaking preventing image portion
appears to the visual sense of the human being as the same color as that of the
oringinal image. However, the color component values of R and B are different in
terms of the color component values of R and B between the color space of R, G,
and B and the color space of R, Cy, and B. Therefore, for example, if a camera
that picks up an image in accordance with the R, G, B method is used to pick up
an image of the display image, then the picked-up display image is reproduced in
a color different from the original color.