Method and system for lossy compression and decompression of computed tomography data

摘要

A compressor and decompressor for CT scanner data first performs a lossless compression of individual CT sample value. After this compression, the compression ratio CR is calculated. This is compared to a target compression ratio. If the target compression ratio is larger or equal than the achieved compression ratio, and additional lossy compression is performed by reducing the number of bits of the lossless compressed values. Immediately after such a lossy compression a lossy decompression is performed within the compressor and the decompressed values stored as history for the compressor keeping the compressor and decompressor in sync. This allows for a better quality of decompressed data while achieving a higher compression ratio.