Multi-fractal Modeling for On-line Text-Independent Writer Identification

The aim of this paper is to address the task of writer Identification of on-line handwriting. A new method for analytical on-line writer identification is proposed. However, although it is possible to measure the degree of handwriting irregularity thanks to the fractal dimension, the fractal analysis with a single exponent is not enough sufficient to characterize handwriting styles variation, instead, a continuous spectrum of exponents is necessary. In this purpose Multi-Fractal analysis was used to characterize styles of writing of writers. The main objective of this study is to explore the utility of this novel statistical tool for the purpose of distinguishing styles of on-line writings. Furthermore, a new method to estimate Multi-Fractal dimensions for on-line handwriting is presented and a procedure to find the most distinctive graphemes is elaborated. To evaluate our method, we have used the writings of 100 writers from the ADAB database. Our experimental results demonstrate the effectiveness of our proposed method and show a large capability of Multi-fractal features to characterize on-line handwriting styles.