Abstract A pseudolinear directional diffusion filter is proposed to enhance the fingerprint images according to their directional infomation. In this paper, the defects of coherent diffusion expressed in a divergence form are discussed which produce a artificial structure and a new nonlinear directional diffusion PDE is proposed to overcome its drawbacks. The new algorithm outperforms the coherent diffusion based image enhancement in denoising ability and structure information preservation. Finally, a pseudolinear expression of the method is proposed and discussed to decrease the computational burden. The pseudolinear method is more suitable to the realtime fingerprint recognition system because of its efficiency.
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2006, Vol. 19 
