关键词: 指纹图像, 纹理, 方向场, 偏微分方程, 图像修复

Abstract: This paper presented a new Partial Differential Equation (PDE) model for fingerprint image restoration, which was an effective method for fingerprint image automatic inpainting. The existing solutions to image inpainting have some drawbacks: satisfactory inpainting results for fingerprint image cannot be provided by common image inpainting models, usually due to the lack of geometric information of the direction field; or because of the introduction of geometric information of the direction field, error results, such as different ridge lines connected to each other, will appear during inpainting process. The main principle of the presented model was to employ the orientation field to act as the constraint of the diffusion directions after comparing and analyzing the existing solutions, and the gray information could be propagated into the inpainting domain along a local fix orientation in the inpainting process, which characterized the orientation of the ridges. The presented model improved normal PDE models for fingerprint image inpainting. The numerical experimental results show that the proposed model is superior to common models at inpainting fingerprint images.

Key words: fingerprint, texture, orientation field, Partial Differential Equation (PDE), image inpainting