Fractional Directional Differentiation and Its Application for Multiscale Texture Enhancement

Figure 7

Texture-enhancement capability comparison. (a) original image, (b) the nonlinearly enhancing the high-frequency components by Butterworth filter, (c) general fractional differentiation of 0.6 order, (d) enhanced image by FDD operator of 0.8 order, (e) original image, (f) the nonlinearly enhancing the high-frequency components by Butterworth filter, (g) general fractional differentiation of 0.8 order, (h) enhanced image by FDD operator of 0.8 order, (i) original image, (j) the nonlinearly enhancing the high-frequency components by Butterworth filter, (k) general fractional differentiation of 0.7 order, (l) enhanced image by FDD operator of 0.3 order, (m) original image, (n) the nonlinearly enhancing the high-frequency components by Butterworth filter, (o) general fractional differentiation of 0.6 order, and (p) enhanced image by FDD operator of 0.9 order.

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