Inertial sensor data compression using modified ADPCM

This paper is concerned with compression of multiple inertial sensor data. The compressed data consists of ADPCM compressed data and an adaptive refinement data. Each sensor data is first compressed using ADPCM. To reduce the quantization errors, refinement quantizers are then used, where the total number of bits for the refinement quantizers is fixed. Which inertial sensor data should be further refined is adaptively determined based on quantization error bounds. In the proposed method, total number of bits for the compressed data is fixed; however the number of bits for individual inertial sensor is adaptively determined. Through experiments, it is shown that the proposed method provides better compression quality than the standard ADPCM with the same total number of bits.