Anisotropic blind image quality assessment: Survey and analysis with current methods

The Anisotropic Quality Index (AQI) was previously introduced by the authors as a non-distortion-specific, no-reference image quality measure. AQI is based on measuring the variance of the expected entropy of a given image over a predefined set of orientations. In this paper, a statistical evaluation of AQI is provided using standard benchmarking parameters showing good match with observer's response. Some AQI extensions are proposed for tackling ill-posed noise types that provide fair or poor performance. A comparison with other no-reference methods has been included showing good competitiveness with many of them.