Transmitting and controlling images from small satellites using MPEG image compression

摘要

Abstract: The limited data rate of low-power small satellites often requires that images be data-compressed before transmission. Several data compression techniques are currently being developed and improved. These methods include: vector quantization (VQ), Lempel-Ziv, fractal encoding, and discrete-cosine transform (DCT) methods such as JPEG and MPEG. JPEG (Joint Photographic Experts Group) is a still-image compression system. MPEG (Motion Picture Experts Group) is a compression and communications protocol which defines a syntax for transmitting several data types, including audio, user-data, and full-motion compressed video. MPEG allows `tolerable' NTSC full-motion video transmission at data rates as low as 1.2 Mbps, and video-conference-quality transmission at rates as low as 56 Kbps. However, since the MPEG standard includes JPEG as a subset, it allows the transmission of compressed still images as well. !4