In this study, a new method, called adaptive image enhancement (AIE), is used to enhance
handwritten document images, such as historical documents. An AIE method is proposed to denoise
handwritten documents in a wavelet domain, which differs from others methods in two aspects: Firstly,
modified contrast limited adaptive histogram equalization (MCLAHE) is used to equalize the contrast
of an image by cutting the histogram at some threshold, and then equalization is used. Secondly, the
image is improved by using directional discrete wavelet transform (D2
WT) enhancing for foreground
and interfering strokes, respectively. As a result, this method not only removes the interfering strokes
or visible watermarks in the background information, but also significantly increases the readability of
handwritten document images.
關聯:
Journal of Applied Science and Engineering19(3), pp.357-370