An evaluation of JPEG and JPEG 2000 irreversible compression algorithms applied to neurologic computed tomography and magnetic resonance images

We performed visual comparison of 200 head magnetic resonance (MR) and 200 head computed tomography (CT) images compressed at two levels using standar d Joint Photographic Experts Group (JPEG) irreversible compression and a pr eliminary version of the JPEG 2000 irreversible algorithm. Blinded evaluati ons by neuroradiologists compared original versus either JPEG or JPEG 2000. We found that this version of JPEG 2000 did not perform as well as the cur rent JPEG for head CTs, but for MR images, JPEG 2000 performed as well or b etter. Around 7:1 compression ratio seemed to be a conservative point where there was no perceptible difference. Copyright (C) 2000 by W.B. Saunders C ompany.