An Iterative Image Restoration Scheme for Degraded Face Images

Abstract: Image restoration is a technique which restore the degraded face images such as faxed images, scanned passport photos and printed images by removing noise in the image. The degradations include half toning, dithering and security watermarks. An iterative image restoration scheme is used to restore the severely degraded face images which improve the recognition performance and the quality of the restored image. In this paper, we study Viola and Jones face detection algorithm which is to localize the spatial extent of the face and determine its boundary. In next step, geometric normalization is applied to both original and degraded images. It holds two processes namely automatic eye detection and affine transformation that matches the images in the database and constructs the canonical faces. Low pass filtering is done using Wiener filter which reduces the noise in the image and the invariant wavelet transform reduces artefacts. Then, the quality of the image is checked using some of the quality metrics and it is restored if the quality is good. Image identification before and after restoration is achieved using certain classification tools and methods. The experimental results demonstrate that our proposed system improved the recognition performance and quality of the image.

Keywords: Face restoration, face recognition, quality metrics, k-nearest neighbour classifier, neural network classifier.