Full-frame cosine transform-based compression of CT, MR, and US images

Compression algorithms based on full-frame discrete cosine transforms have achieved compression ratios as high as 10:1 to 20:1 with almost imperceptible image degradation, when applied to projection radiographs digitized with 2,048 x 2,048 x 8-bit matrices. Images from CT, MR imaging, and US are smaller, have lower signal-to-noise ratios, and in the case of CT, have larger dynamic range. This results iin qualitatively different spectral properties. The authors present the results of a study on the efficiency of the full-frame technique applied to images from these digital modalities. In summary, they find that they can achieve excellent results with compression ratios in the neighborhood of 5:1. The study was performed on a hardware implementation of their algorithm that can compress a 512 x 512 image in less than 1.5 seconds