| 摘要 |
PURPOSE:To automatically decide the picture quality with high accuracy by providing a variance detecting part to output the variance value of the picture signals of an image process subject and estimating the noise level based on the variance value. CONSTITUTION:A picture quality deciding device is provided with a variance detecting part 12 which outputs the variance value of the picture signals of an image process subject and a picture quality deciding part 14 which decides the picture quality of the subject based on the variance value. For instance, the picture signals of a white ground and the character lines are obtained if the picture data on a white ground form where the characters are written contain no noise. Then the picture signals of the white ground and the character lines are obtained if the picture data includes the noises. The variance of the picture signals is increased with the picture data including noises compared with the picture data including no noise. Thus the noise level can be estimated based on the detected variance value of the picture signals and the picture quality can be decided. |
