Medical image compression apparatus, a target image is a medical image to be compressed, the compression target acquisition unit that acquires the observation data of the target image (100), based on the findings information, divides the target image into area of each pathology pathological range acquiring section that (130), for any pixel, the prediction knowledge database that holds corresponding to the pixel value included in around a predetermined range, the frequency distribution of the pixel values of an arbitrary pixel in each pathology (180) Referring to, condition of the prediction target pixel, and based on the frequency distribution of the pixel values of the predicted pixel, the pixel value predicting unit for calculating the predicted probability of the pixel value of the prediction target pixel as (190), the pixel value Based on the prediction probability of the prediction unit (190) is a pixel value calculated, an encoding unit for encoding the pixel value of a predicted pixel (200), predicted after being encoded by the encoding unit (200) It comprises an output section for outputting a code of a pixel and the (210).医用画像圧縮装置は、圧縮対象の医用画像である対象画像と、対象画像の所見情報とを取得する圧縮対象取得部(100)と、所見情報に基づいて、対象画像を病態毎の領域に分割する病態範囲取得部(130)と、任意の画素について、予め定められた周辺範囲に含まれる画素値に対応する、任意の画素の画素値の頻度分布を病態毎に保持している予測知識データベース(180)を参照し、予測対象画素の病態、及び予測対象画素の画素値の頻度分布に基づいて、予測対象画素の画素値の予測確率を算出する画素値予測部(190)と、画素値予測部(190)が算出した画素値の予測確率に基づいて、予測対象画素の画素値を符号化する符号化部(200)と、符号化部(200)により符号化された後の予測対象画素の符号を出力する出力部(210)とを備える。
