Result and Discussion - Segmentation of Hand Bone for Bone Age Assessment - page 104

Fig. 4.2 The radiograph is diffused by different algorithm for comparison. a Original image.
b Gaussian filter. c Average filter. d Wiener filter. e Symmetric Nearest Neighbor ( SNN ) filter.
f Anisotropic diffusion

Table 4.1 Comparison of expected image homogeneity of different age group before and after
the anisotropic diffusion processing
Age group Image homogeneity Image homogeneity

Before anisotropic diffusion After anisotropic diffusion

0-2 0.7056 0.8235

3-6 0.6984 0.8245

7-9 0.7132 0.8365

10-12 0.7189 0.8423

13-15 0.7028 0.8212

16-18 0.6927 0.8234

the edge has not been diffused and thus details are retained. Edges of structures, thus,
are intensified to facilitate identification. Moreover, the anisotropic diffusion is able to
manipulate the intensity and direction of diffusion to prevent diffusion across the edges;
instead it enables diffusion in direction parallel along the edges; therefore, edges are
preserved and are enhanced simultaneously. This is important in distinguishing the ana-
tomical structures outlines in medical image processing.