Patent ID: 6072913
Filing Date: 2000-06-06
Classification: G06T

Abstract:
An image processing method, wherein a signal concerning high frequency components of an original image signal, which represents an original image, is added to the original image signal, the high frequency components of the original image signal being thereby emphasized, and wherein a signal concerning low frequency components of the original image signal is added to the original image signal, the dynamic range of the original image signal being thereby compressed, the method comprising the steps of:i) forming a plurality of unsharp mask image signals, which have different frequency response characteristics, from the original image signal,ii) forming a plurality of band-limited image signals, each of which represents one of signals falling within a plurality of different frequency bands of the original image signal, from the original image signal and the plurality of said unsharp mask image signals, or from the plurality of said unsharp mask image signals,iii) obtaining the signal concerning the high frequency components of the original image signal by:carrying out a first converting process on at least one band-limited image signal, which is among the plurality of said band-limited image signals, such that at least a portion of the band-limited image signal becomes small, a plurality of first converted image signals being thereby formed, andintegrating the plurality of said first converted image signals,iv) obtaining the signal concerning the low frequency components of the original image signal by:carrying out a second converting process on at least one band-limited image signal, which is among the plurality of said band-limited image signals, such that at least a portion of the band-limited image signal becomes small, a plurality of second converted image signals being thereby formed,integrating the plurality of said second converted image signals, an integration signal being thereby formed,subtracting said integration signal from the original image signal, a difference signal being thereby formed, andconverting said difference signal, andv) adding the signal concerning the high frequency components and the signal concerning the low frequency components to the original image signal, thereby the high frequency components of the original image signal are emphasized and the dynamic range of the original image signal is compressed.