On the multiresolution enhancement of document images using fuzzy logic approach

Presents a method for enhancing document images that is based on the wavelet transform and fuzzy logic approach. The document image to be enhanced is obtained as a blurred binary image from a scanner and corrupted by additive noise. This type of image occurs in many situations when the quality of the documents including checks, hand-written text, credit card receipts become noisy and low-contrast images after scanning. Our problem is to improve such images by reducing noise and increasing the contrast of the text. This can be achieved by incorporating the wavelet transform, fuzzy logic and a contrast enhancement operator. The improvement is demonstrated by using simulation examples and compared in terms of visual enhancement with the more conventional approaches