Evaluation of Image Quality Assessment Metrics: Color Quantization Noise

Although color quantization noise is frequently met in practice, it has not been given too much attention in color image visual quality assessment. In this paper, a new image database for the evaluation of image quality metrics over color quantization noise is described. It contains 25 reference images and 875 test images produced by five popular quantization algorithms. Each of the quantized images was evaluated by 22 human subjects and more than 19200 individual human quality judgments were carried out to obtain the final mean opinion scores. A comparative analysis of several well-known image quality metrics is presented and their correlation with the human opinion scores is evaluated. This image database has been made freely available for downloading for research in image quality assessment and other applications [10].