<title>Image quality metrics based on scale</title>

Abstract

This paper presents a method to evaluate image quality using the continuous wavelet transform. The method utilizes a bank of filters tuned to different scales and orientations to extract the image details. The filters are designed according to the criterion suggested by Antoine and Murenzi.1 The wavelet transform of a given image and the reconstructed images at various quality levels are represented in the form of energy density plots. These density plots highlight image features such as edges, object boundaries and texture. Thus, they represent the details contained in the image. A quality metric is proposed based on the absolute difference between the energy densities corresponding to the original and reconstructed images. The proposed metric is used to measure the relative quality of the image. In addition, the metric is also used to study the performance of a specific ATR (automatic target recognition) algorithm as a function of image quality.