Amincissement-sans-segmentation et rehaussement des images de niveau de gris par un filtre de chocs utilisant des champs de diffusion

Amincissement-sans-segmentation et rehaussement des images de niveau de gris par un filtre de chocs utilisant des champs de diffusion

Segmentation-Free Thinning and Enhancement of Grayscale Images by Shock Filter and Diffusion Fields

Mohamed Cheriet Vincent Doré 

Laboratoire d'imagerie, de vision et d'intelligence artificielle, École de technologie supérieure 1100 Notre-Dame Ouest,Montréal, PQ-H3C-1K3, Canada

Corresponding Author Email: 
mohamed.cheriet@livia.etsmtl.ca
Page: 
79-94
|
Received: 
10 January 2006
|
Accepted: 
N/A
|
Published: 
28 February 2006
| Citation

OPEN ACCESS

Abstract: 

In the scope of gray-level image processing and understanding, thinning is certainly a central shape descriptor for image analysis and pattern recognition. Enhancement is also an essential tool in facilitating the visual interpretation and understanding of images, especially for noisy and blurry ones. The lack of general unified frameworks necessitates the investigation of these problems in a coherent fashion, using partial differential equations. In this paper, we present a method for thinning and enhancing images by using a shock filter derived from our previously work introduced on enhancement. This new filter incorporates specific diffusion fields and since each such field is characteristic of a given application, it brings a new degree of freedom to the shock filters, in order to address problems of greater practical interests. Probative results on handwritten documents illustrate the performance and efficiency of our model. Other applications have been added in order to highlight its efficiency.

Résumé

L’amincissement est assurément un descripteur de forme majeur pour l’analyse d’image et la reconnaissance de forme. Le rehaussement est aussi un outil essentiel pour faciliter l’interprétation visuelle et la compréhension des images de documents notamment celles qui sont bruitées et floues. Nous décrivons dans cet article une méthode d’amincissement et de rehaussement utilisant un filtre de chocs dérivant de celui introduit par Remaki et Cheriet pour le rehaussement. Ce nouveau filtre utilise un champ de diffusion spécifique initial. L’utilisation de tels champs apporte un nouveau degré de liberté aux filtres de chocs, puisque ceux-ci sont spécifiques aux applications (amincissement, rehaussement) et permettent ainsi au même filtre d’être utilisé pour différentes applications. Nous illustrons la performance de notre méthode par des résultats probants obtenus sur des images manuscrites.

Keywords: 

Partial Differential Equations (PDE’s), thinning, enhancement, diffusion field, mathematical morphology, grayscale images

Mots clés

Équation aux dérivées partielles (EDP), amincissement, rehaussement, champ de diffusion, morphologie mathématique, images manuscrites

1. Introduction
2. Rappels Des Travaux Précédents
3. Extension Du Modèle
4. L’amincissement
5. Résultats Et Discussion
5. Conclusion
  References

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