Analysis of variable-length codes for integer encoding in hyperspectral data compression with the k²-raster compact data structure

This paper examines the various variable-length encoders that provide integer encoding to hyperspectral scene data within a k²-raster compact data structure. This compact data structure leads to a compression ratio similar to that produced by some of the classical compression techniques. This compact data structure also provides direct access for query to its data elements without requiring any decompression. The selection of the integer encoder is critical for obtaining a competitive performance considering both the compression ratio and access time. In this research, we show experimental results of different integer encoders such as Rice, Simple9, Simple16, PForDelta codes, and DACs. Further, a method to determine an appropriate k value for building a k²-raster compact data structure with competitive performance is discussed.