摘要 |
<p>A new image (S min ij) is generated from an image signal (Sij) by determining whether the configuration of the distribution of the image signal (Sij) at a point of interest (i, j) is upwardly convex, or a downwardly convex, or otherwise, employing, as the new image signal (S min ij), the original image signal (Sij) at the point of interest (i, j) if the configuration is upwardly convex or downwardly convex, and employing, as the new image signal (S min ij), an unsharp signal (Uij) if the configuration is otherwise. A differential signal (Sij - Uij), or an absolute signal ¦Sij Uij¦, or a square signal ((Sij - Uij)<2>), or a Laplacian signal ( NABLA <2>Sij) is compared with a threshold signal (T) to determine whether the configuration of the distribution of the image signal (Sij) at a point of interest (i, j) is upwardly convex, or a downwardly convex, or otherwise. The unsharp signal (Uij) comprises an average signal (Uaveij) or a median signal (Umedij) in a region including the point of interest (i, j). A sharpness emphasizing signal (S*ij) is calculated from the new image signal (S min ij) and the unsharp signal (Uij) according to the equation: S*ij = S min ij + K(S min ij - Uij) where K is a coefficient signal.</p> |