Implementation Aspects of a Decompressor for Compressed METEOSAT Data on a VME/68000 System

摘要

The results are presented of a feasibility study into some aspects of a proposed METEOSAT image data compression unit. For the considered algorithms, an estimate of the needed processing power based on the 68000 instruction set was made. This showed that a multiprocessor 68000 system would be capable of performing this task. For the estimate it was necessary to code part of the decompression algorithms. The coding of the algorithms has to be done in assembler to utilize the 68000 optimal and reach the required speed. The varying effective compression ratio of the considered algorithms and the limited output rate of the decompression require a buffer to store the incoming data. The required buffer size depends on the in- and output speed of the decompressor and the compression ratio of the incoming data.