Fundamentals of Digital Image Processing - Control of Color Imaging Systems: Analysis and Design - page 84

FIGURE 2.51 Original LENA image.

FIGURE 2.52 Blurred noisy LENA image.

The blurred and noisy image is shown in Figure 2.52. The restored image using
the inverse

filter is shown in Figure 2.53. As shown, the inverse filter ampli es the

noise to an extent that the image is not visible. The restored image using

the Wiener filter reduces the noise

effect and the resulting image is closer to the original image than the inverse

filter is shown in Figure 2.54. The Wiener

filtered image. The best result is obtained when a ¼ 0 : 01 in the Wiener filter.

2.10 IMAGE HALFTONING
Digital image halftoning converts a gray scale image to a binary image for display
and printing on binary devices. Most of the printed images in this topic are halftone
images. Halftone images appear as if they are gray scale images. This is due to local