Open Access

ARTICLE

An Optimized Implementation of a Novel Nonlinear Filter for Color Image Restoration

by Turki M. Alanazi^*

Department of Electrical Engineering, College of Engineering, Jouf University, Sakaka, Saudi Arabia

* Corresponding Author: Turki M. Alanazi. Email:

(This article belongs to the Special Issue: Optimization Problems Based on Mathematical Algorithms and Soft Computing)

Intelligent Automation & Soft Computing 2023, 37(2), 1553-1568. https://doi.org/10.32604/iasc.2023.039686

Received 11 February 2023; Accepted 11 April 2023; Issue published 21 June 2023

Abstract

Image processing is becoming more popular because images are being used increasingly in medical diagnosis, biometric monitoring, and character recognition. But these images are frequently contaminated with noise, which can corrupt subsequent image processing stages. Therefore, in this paper, we propose a novel nonlinear filter for removing “salt and pepper” impulsive noise from a complex color image. The new filter is called the Modified Vector Directional Filter (MVDF). The suggested method is based on the traditional Vector Directional Filter (VDF). However, before the candidate pixel is processed by the VDF, the MVDF employs a threshold and the neighboring pixels of the candidate pixel in a 3 × 3 filter window to determine whether it is noise-corrupted or noise-free. Several reference color images corrupted by impulsive noise with intensities ranging from 3% to 20% are used to assess the MVDF’s effectiveness. The results of the experiments show that the MVDF is better than the VDF and the Generalized VDF (GVDF) in terms of the PSNR (Peak Signal-to-Noise Ratio), NCD (Normalized Color Difference), and execution time for the denoised image. In fact, the PSNR is increased by 6.554% and 12.624%, the NCD is decreased by 20.273% and 44.147%, and the execution time is reduced by approximately a factor of 3 for the MVDF relative to the VDF and GVDF, respectively. These results prove the efficiency of the proposed filter. Furthermore, a hardware design is proposed for the MVDF using the High-Level Synthesis (HLS) flow in order to increase its performance. This design, which is implemented on the Xilinx Zynq XCZU9EG Field-Programmable Gate Array (FPGA), allows the restoration of a 256 × 256-pixel image in 2 milliseconds (ms) only.

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