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Enhancement of historical documents by image processing techniques

Historical documents are valuable source of information but commonly suffer from degradation problem. The task is to keep these documents alive to preserve the important information and the heritage of a country. The main aim of this paper is to transform them into digital form and enhance the quality and visualization of the historical images. Image processing techniques such as noise filtering, histogram equalization and power law transformation have been used to result in better representation of images. To evaluate the quality of resultant image, two performance assessment parameters; entropy and standard deviation, have been used. Matlab results indicate the efficacy of proposed technique to remove the background noise and thereby improving the quality of historical degraded images. The proposed method is much easier and may help to archive the documents in digital images with improved quality.