Image enhancement and binarization method research for the Dai palm leaf manuscripts

In order to solve the problem that the background of Dai palm leaf manuscripts was not uniform and the contrast between character and the background was low,a method combining image enhancement and Sauvola algorithm was proposed.Firstly,the homomorphic filtering was applied to remove the inhomogeneity in the background of Dai palm leaf manuscripts.Subsequently,the linear gray transform was performed to enhance the contrast of the Dai palm leaf manuscripts' image.Finally,the Sauvola algorithm was applied to binarize the Dai palm leaf manuscripts' image.Experiment results showed that the proposed method could solve the uneven background and low contrast of Dai palm leaf manuscripts' image effectively and obtained a clear binary image.Furthermore,the proposed method,combined Sauvola algorithm with the homomorphic filtering and linear gray transform,was more suitable for Dai palm leaf manuscript image binarization compared with the traditional methods.