Joint Photograph Experts Group
A common format developed by the Joint Photographic Experts Group for compressing image files in RGB mode, using which file sizes of images can be reduced by up to 95 percent.
Though it involves a loss of image information, the degree of compression can be selected so that the losses remain within acceptable limits. JPEG requires no license and is internationally standardized (ISO 10918).
It uses the “Discrete Cosine Transformation” (DCT) method, where image sections of 64 pixels each are processed.
A new compression method, known as JPEG 2000, is currently being developed, which uses what are known as “wavelets” and is said to be able to compress images by 20 percent more than JPEG with better image quality. JPEG 2000 will support non-lossy compression, as well as other color modes (such as CMYK) and color management.