1. An image processing method comprising the steps of: i) carrying out a morphology operation on an original image signal Dorg, which represents an image, by using a multiply structure element Bi and a scale factor .lambda., a morphology signal Dmor being thereby obtained, said morphology signal Dmor representing whether each of picture elements constituting said image is or is not an element corresponding to an image portion at which said original image signal Dorg fluctuates in a spatially narrower range than said multiply structure element Bi, and ii) carrying out image emphasis processing on said original image signal Dorg and in accordance with said morphology signal Dmor; wherein the image emphasis processing in accordance with said morphology signal Dmor is carried out with Formula (2) EQU Dproc=Dorg+.alpha.f(Dmor) (2) wherein .alpha. represents the emphasis coefficient, and f(Dmor) represents the function of Dmor; and the function f(Dmor) in accordance with said morphology signal Dmor is an unsharp mask signal corresponding to super-low frequency of said morphology signal Dmor as represented by Formula (4) EQU f(Dmor)=(.SIGMA..SIGMA.Dmor)/N.sup.2 ( 4) wherein .SIGMA..SIGMA. Dmor represents the sum of the morphology signal values with respect to the picture elements located within a picture element matrix, which has a size of N columns.times.N rows (where N represents an odd number) and has its center at the picture element, that is associated with the morphology signal Dmor, in a two-dimensional array of picture elements.