Hardware implementation and clinical evaluation of irreversible image compression

A new technology for irreversible medical-image compression (modified two-dimensional DCT and bit-allocation technique) was developed to implement a picture archiving and communications system. Image degradation is minimized by taking care of the coefficients lost during the process. Using this method, the authors report that they were able to display various kinds of reconstructed computed radiography images with various compression ratios on a 1,536-line cathode ray-tube monitor. Radiologists evaluated the comparative quality of these images. Receiver operating characteristic studies were also carried out to determine the agreeable compression ratio for clinical use. Acceptable compression ratios depended on the type of target lesion