Abstract: In a sharpening process of image data using a Laplacian operation, a parameter k for controlling the size of a Laplacian to be subtracted from an original image, a parameter ? for suppressing influences of noise and a parameter ? for suppressing an overshoot and an undershoot are respectively provided, and these parameters are altered in accordance with the state of an original image. Thus, it becomes possible to carry out the sharpening process on the image data without causing emphasized noise and occurrences of an overshoot and an undershoot.

Abstract: In a sharpening process of image data using a Laplacian operation, a parameter k for controlling the size of a Laplacian to be subtracted from an original image, a parameter &thgr; for suppressing influences of noise and a parameter &lgr; for suppressing an overshoot and an undershoot are respectively provided, and these parameters are altered in accordance with the state of an original image. Thus, it becomes possible to carry out the sharpening process on the image data without causing emphasized noise and occurrences of an overshoot and an undershoot.

Abstract: A photographic copying apparatus has a DX code reader for reading a DX code or identification code on negative film, a film scanner for acquiring density information of the negative film, and an exposure station for exposing printing paper. The exposure station is controlled based on exposure information derived from conversion information selected with reference to the identification and density information. A reference film is test-coped for correction purposes, and conversion information for plural types of film is corrected based on density of the test copy and density of the reference film measured by the film scanner.