摘要 |
An apparatus and method are described for predicting a subjective quality rating associated with a reference image compressed at a given level. My apparatus includes means for, and my method includes steps of, storing a digitized color image representing a reference image in memory (110) and compressing (120, 620) at a given level and decompressing (130, 630) the reference image to produce a processed image. My apparatus and method also entail converting the reference image and the processed image each to a grayscale image (140, 640, and 740) and dividing each grayscale image into an array of blocks (150, 650, and 750). My apparatus and method further entail generating a first intensity variance array corresponding to the array of blocks of the grayscale reference image (160, 760) and a second intensity variance array corresponding to the array of blocks of the grayscale processed image (160, 660). Lastly, my apparatus and method entail a variance ratio based on the first and second intensity variance arrays (170, 670) determining a block variance loss based on the variance ratio (180, 680), and generating the subjective quality rating indicated by the impairement level which is based on the variance loss (190, 690).
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