Compression procedure for seismic sampling data has two part data word

摘要

Compression of seismic numerical sample data where the data samples are stored or transmitted in cells which are composed of data words of variable length, with the useful data being in a variable length part and a prefix coding part which gives the length of the data and is of fixed length. The different possible lengths for the data part of the data word are chosen using a statistical function based on the distribution of lengths of the data part of the word in such a way as to optimise the average data word length including the prefix part. The prefix part of each cell is such that cells less likely to occur have a longer prefix part, while those more likely to occur have a shorter prefix part. The sample data is time coded.