1. < data , graphics > Data representing a two-dimensional scene. A digital image is composed of pixels arranged in a rectangular array with a certain height and width. Each pixel may consist of one or more bit s of information, representing the brightness of the image at that point and possibly including colour information encoded as RGB triples.
Images are usually taken from the real world via a digital camera , frame grabber , or scanner ; or they may be generated by computer, e.g. by ray tracing software.
See also image formats , image processing .
2. The image (or range) of a function is the set of values obtained by applying the function to all elements of its domain . So, if f : D -> C then the set f(D) = \ f(d) | d in D \ is the image of D under f. The image is a subset of C, the codomain .