Abstract    This paper proposes a new hybrid method based on Homomorphic filtering and anisotropicdiffusion equations for image denoising. In this method, the Homomorphic filtering extracts the reflectionand illumination components of a noisy image. Then a suitable image denoising method based onanisotropic diffusion is applied to each components with its special user-defined parameters .This hybridscheme donates a flexibility and customizability to the method, due to its ability to separately enhanceeach component properly. In order to evaluate the proposed method effectiveness, a number ofexperiments have been performed and the results have been compared with the results of other pioneeringmethods. The good results indicate superiority of proposed method.

Keywords    Image denoising, Image smoothing, Anisotropic diffusion, Homomorphic filtering, Hybrid image enhancement

چکیده    در این مقاله، یک روش ترکیبی جدید مبتنی بر فیلتر همومورفیک و معادلات انتشار حرارت نامتقارن برای حذف نویز تصویر پیشنهاد شده است. در روش پیشنهادی با استفاده از فیلتر همومورفیک، تصویر نویزی به دو مولفۀ روشنایی و انعکاس تفکیک می­شود. سپس هر یک از این دو مؤلفه، بطور جداگانه و با پارامترهای خاص آن مولفه، که توسط کاربر تعریف شده‌اند، تحت تأثیر توابع نامتقارن انتشار حرارت قرار گرفته، نویززدایی می­شوند. این روش ترکیبی، بدلیل توانایی آن در بهسازی بهینۀ هر یک از مؤلفه­ها بصورت تفکیک شده، و امکان تأکید بر اهمیت و تأثیرگذاری هر مؤلفه بطور خاص، انعطاف پذیری و آزادی عمل بالایی را فراهم می‌کند. به منظور ارزیابی روش پیشنهادی، تعدادی آزمایش انجام و نتایج آن با چندین روش پیشرو مقایسه شد. نتایج این آزمایشات نشان می­دهند که روش پیشنهادی نسبت به الگوریتم­های کلاسیک این حوزه عملکرد بهتری از خود نشان می­دهد.

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