ABSTRACT
Digital images have two different resolutions. One is the intensity resolution which is the number of intensity levels that any pixel can realize. The second is spatial resolution which is the number of distinct pixels in each dimension. The intensity resolution of an image refers to the number of gray levels that each pixel can realize. Quite commonly a pixel in a grayscale image will have 256 different intensity levels. A bitmap image stores that image with one byte per pixel for grayscale images and three bytes per pixel for color images. Each of the formats has a few bytes at the beginning of the file to store information such as the dimensions of the image. The Joint Photographic Experts Group (JPEG) format is commonly used for photographs. The JPEG compression converts the image from red, green and blue to YCbCr, and the two chroma channels are reduced to half of their original size.
