| 摘要 |
PROBLEM TO BE SOLVED: To estimate the quantity of the granularity of an image. SOLUTION: A wavelet converting means 10 performs wavelet conversion for source image data S representing a source image to obtain image data HH0, HL0, LH0, and HH1 representing images for frequency bands. A comparing means 11 compares pixel values of respective pixels of the image data HL0, LH0, and HH1 with specific threshold values Th1, Th2, and Th3 respectively and extracts pixels corresponding to pixels satisfying HL0<Th1, LH0<Th2, and HH1<Th3 from the image data HH0. A dispersion value calculating means 12 finds dispersion values B of pixel values of the extracted pixels and an estimating means 13 estimates the granularity of the source image to be large when the dispersion value B is larger than a threshold value (a) and small when the dispersion value B is smaller than the threshold value (a). |
