On Implementing The Jpeg Still-Picture Compression Algorithm
Rangarajan Aravind, Glenn L. Cash, J. P. Worth · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1989
In this paper, we discuss an implementation of a compression technique for still images that is currently being proposed as a standard by the Joint Photographic Experts Group (JPEG), a specialists group working under the aegis of the International Organization for Standardization (ISO) and the CCITT. We discuss first the overall configuration of the compression system, and then we describe the general implementation of the encoder and decoder. The system we pay most attention to is a hierarchical system which encodes an image in three stages. Last, we focus on a DSP-based system that can perform the decoding operation in real-time for a channel data-rate of 64 kbps. This hardware has been built with only off-the-shelf boards. It is capable of decoding and displaying a coarse first-stage image compressed to 0.25 bits/pixel in about one second, a second-stage update compressed to 0.5 bits/pixel in roughly two seconds, and finally a third-stage update compressed to 1.5 bits/pixel (for a total overall bit-rate of 2.25 bits/pixel) in five seconds.