A compression scheme for radio data in high performance computing

TL;DR

This paper introduces a novel compression scheme for astronomical radio data that combines a nearly lossless rounding step with a new lossless compression algorithm, achieving significant size reduction and high decompression speeds for high-performance computing applications.

Contribution

The paper presents a new compression pipeline using a calibration-independent rounding method and the Bitshuffle algorithm, optimized for high throughput in radio astronomy data processing.

Findings

Data compressed to 28% of original size

Decompression speeds exceed 1 GB/s on a single core

Applicable to data from CHIME Pathfinder telescope

Abstract

We present a procedure for efficiently compressing astronomical radio data for high performance applications. Integrated, post-correlation data are first passed through a nearly lossless rounding step which compares the precision of the data to a generalized and calibration-independent form of the radiometer equation. This allows the precision of the data to be reduced in a way that has an insignificant impact on the data. The newly developed Bitshuffle lossless compression algorithm is subsequently applied. When the algorithm is used in conjunction with the HDF5 library and data format, data produced by the CHIME Pathfinder telescope is compressed to 28% of its original size and decompression throughputs in excess of 1 GB/s are obtained on a single core.