Problem to be solved: to provide an image processing apparatus, an operation method of the image processing apparatus, and an image processing program to emphasize the change in color of the mucosa, etc., which may occur when atrophy of the stomach due to atrophic gastritis.Solution: an endoscope image constituted by an image signal including a narrow band image signal is acquired, and a color difference vector p from the reference color s representing the color of the normal portion of the endoscope image to the color P of each of the target pixels in the endoscope image is obtained in the color space containing the luminance, and the color P of each of the target pixels is color difference beak The color difference expansion processing which converts the color difference expansion vector added in the same direction as the Torr p to the color Q added to the reference color is carried out.An image is obtained by extending the color difference between the normal portion and the abnormal part, which has been subjected to the color difference expansion processing to all pixels of the endoscopic image.Diagram【課題】萎縮性胃炎による胃の萎縮時に起こり得る粘膜等の色の変化を強調するための画像処理装置、画像処理装置の作動方法、および画像処理プログラムを提供する。【解決手段】狭帯域画像信号を含む画像信号により構成された内視鏡画像を取得し、輝度を含む色空間において、内視鏡画像の正常部の色を表す基準色Ｓから内視鏡画像中の各注目画素の色Ｐまでの色差ベクトルｐを取得して、各注目画素の色Ｐを、色差ベクトルｐと同一方向に強調量を加えた色差拡張ベクトルを基準色に加算した色Ｑに変換する色差拡張処理を施す。色差拡張処理を内視鏡画像の全ての画素に施した正常部と異常部の色差を拡張した内視鏡画像を出力する。【選択図】図５
