ABSTRACT
To understand issues regarding the capture, use, delivery, storage and preservation of digital images, it is necessary to understand the fundamental aspects of how digital images function. Given that the majority of digital images created by the home or professional user are bitmaps (see Chapters 5 and 6), this chapter details the fundamental characteristics of bitmap images and the underlying principles which drive bitmap representation: the individual pixels within the grid; the colour information stored about each pixel (bit depth); the spacing of individual pixels (resolution); changing image size (interpolation); and issues regarding file size and the compression of bitmap information. It also highlights various issues of relevance to the information professional working with digital image data.
