Evaluating the Impact of Iris Image Preprocessing on CNN-Based Biometric Recognition Performance
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Abstract
Iris-based biometric recognition is a reliable identification technique because the iris pattern is unique and remains stable throughout an individual's lifetime. However, the quality of iris images significantly affects the accuracy of recognition systems, particularly when images are degraded by noise, uneven illumination, and occlusions caused by eyelashes and eyelids. This study investigates the impact of several image preprocessing techniques on the performance of an iris biometric recognition system. The preprocessing pipeline consists of image resizing, pixel value normalization, contrast enhancement using Contrast Limited Adaptive Histogram Equalization (CLAHE), and noise reduction through Gaussian filtering. The CASIA-IrisV1 dataset was employed for model development and evaluation, while a Convolutional Neural Network (CNN) was used as the classification model. Experimental results demonstrate that the proposed preprocessing pipeline improves the iris recognition accuracy from 91.2% to 96.4%. These findings indicate that image quality enhancement through appropriate preprocessing plays a crucial role in improving the robustness and accuracy of CNN-based iris biometric recognition systems.
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