Research And Implementation Of Automatic Font Outline Generation For NÇšshu

Nǚshu is the only female character in the world which does not belong to any nationor rely on any kind of religions. At present Nǚshu is inherited by the way of handwritten.As the heritors of Nǚshu died, Nǚshu is in endangered status. Digital processing whichcan store, display and process Nǚshu in computers conveniently, is of great significanceto the heritage and development of Nǚshu.According to the characteristics of Nǚshu character, a curve-outline generationsystem for Nǚshu is designed and implemented in this paper based on the relatedtechnologies at home and abroad. The implemented system can be used to standardizeNǚshu characters and generate the high-precision curve-outline characters of Nǚshu.The major research content in this paper is as follows:(1) A method for standardizing Nǚshu character based on skeleton is proposed for thephenomenon of inconsistent stroke width and edge burrs in Nǚshu character. Firstly, forthe disadvantage of ZS thinning algorithm, a post-processing step by identifying thecrucial patterns is applied so as to produce one pixel thick skeleton. Secondly, a burrremoving iteration algorithm is used to remove the burrs which affect the topologicalstructure of Nǚshu character in the skeleton. And then in the process of distortion pointcorrection, Quadratic-Bezier curve is introduced to connect the feature points in order toform smooth and continuous skeleton. At last morphological dilation is used on theskeleton. The result shows that for some Nǚshu samples, the standard Nǚshu characterswhich have identical stoke width and the same topology as the original fonts can begotten by the proposed method.(2) For the disadvantages of bitmap font, such as large storage, the quality ofzooming is hard to guarantee, an approach for auto-generating curve-outline characterfrom bitmap based on straight lines and Cubic-Bezier curves is designed and realizedfor Nǚshu. The main idea of the implementation is to extract the contour data of Nǚshucharacter firstly, Secondly, three direction tracking templates are introduced in order tomake the contour points ordered. And then a simple approach for detecting featurepoints based on feature point suppression is proposed to divide contour segmentsaccurately. At last, the contour segments are fitted by straight lines or Cubic-Beziercurves. The result shows that the generated curve is basically the same as the originalcontour, the burrs caused by hand-writing also can be eliminated and the storage spacein computer can be reduced greatly. (3) In order to alter the shape of the Cubic-Bezier curve, the control points must bechanged, for this disadvantage, a Cubic-Bezier curve with two parameters is introducedto fit the contour of Nǚshu characters which have the smooth contours, and the geneticalgorithm is used to solve the parameter optimization. Firstly, the mathematical modelbased on least square fitting for Cubic λμ-Bezier curve is established. And then thegenetic algorithm is introduced to calculate the best parameters adaptively forgenerating high-precision fitting curves. The result shows that the fitting precision ofNǚshu font generated by the proposed method is improved, and the characteristic ofNǚshu characters is reserved precisely. The dynamic fonts of Nǚshu can be generatedbased on the existing fonts by the characteristic of two shape parameters, and theproposed method lays the foundation of realizing deformation of Nǚshu fontsautomatically.