Online Text-independent Writer Identification Based on Temporal Sequence and Shape Codes

In this paper we present a novel method for online text-independent writer identification. Most of the existing writer identification techniques require the data to be from a specific text which is not applicable to cases where such text is not available, such as in criminal justice systems when text documents with different content need to be compared. Text-independent approaches often require a large amount of data to be confident of good results. We propose temporal sequence and shape codes to encode online handwriting. Temporal sequence codes (TSC) are to characterize trajectory in speed and pressure change in writing, and shape codes (SC) are to characterize direction of trajectory in writing handwriting. For TSC, we use two different codes to encode speed and pressure to codebook: stroke temporal sequence codes (STSC) and neighbor temporal sequence codes (NTSC). At identification stage, we implement decision and fusion strategy to identify writer. Experimental results show that our proposed method can improve the identification accuracy with a small number of characters. Moreover, we find that the proposed method is even effective for cross-language (English & Chinese) writer identification.