Olympus FLUOVIEW FV300 - Noise Reduction

APPLIED OPERATIONS/Image Processing
IV. OPERATION INSTRUCTIONS
IV . 2-229
Page
5 Prewitt filter
This filter enhances the contours of image grains in a similar way to the Sobel filter, but
more strongly than it. It has two filter formats, X and Y, as shown below. The format
providing the larger value after filtering is used.
XY
-2 -2 -2 -2 0 2
000 -202
222 -202
The operation method is identical to Laplacian filtering except for the following point. See
section 2-6-1-1-1, “Laplacian filter”.
z Click the <Prewitt> button.
2-6-1-2 Noise Reduction
When random noise interferes with an image, its irregularity increases and it become
harder to see. Such noise can be reduced by means of filtering. Three kinds of filters are
available for noise reduction.
1 Averaging filter
The averaging filter is used to eliminate details in image or reduce noise. However, as it
makes everything in an image smooth, it also makes the edge sections dull, which
sometimes result in the image resolution deterioration. The filter format is as shown
below.
111
111
111
The operation method is identical to Laplacian filtering except for the following point. See
section 2-6-1-1-1, “Laplacian filter”.
z Click the <Average> button.
<Prewitt> button
<Average> button
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