Article

Some applications in image procession with wavelets

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Abstract

This paper introduces some applications in image processing with wavelets, such as edge detection, pattern recognition and image segmentation. Edge detection includes contour extraction and background removal for an illustration of gray - level, extraction of tumor region in color image and enlargement of type size of Chinese character. As for recognition of Chinese character or character at first, we can reduce the dimensionality of two dimensional patterns to one dimensional sign, then do wavelets decomposition for these one dimensional patterns, at last compute fractal dimension of each sub - pattern, so feature vectors can be obtained and used to recognition. The characters after affine transformation can also be recognized by a dyadic wavelet affine invariant function. At last we introduce two means of image segmentation. One is based on energy analysis, another is singularity analysis.

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... (3) becomes binary wavelet transform [11]: ...
... They are the first-order derivative of the smoothening image along horizontal and vertical direction respectively and can be viewed as two components of the gray gradient vector of image f(x,y) smoothed by function 2 ( , ) j x y . The modulus and phase angle of gray gradient vector are [11]: ...
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