| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a luminance value arithmetic unit with which accurate luminance value of image can be calculated, even when contrast is not clear and S/N ratio is poor, and to provide a data reproduction device that uses the unit. <P>SOLUTION: The arithmetic unit is provided with a histogram generation means 105 for generating a histogram of luminance in a prescribed range of a digital image 101 obtained, by photographing a medium in which binary data are recorded two-dimensionally, in which the existence ratio of first data and second data is a specific ratio; an average value generation means 106 for generating the average value of the luminance in the prescribed range of the digital image 101; a dark value arithmetic means 107 for obtaining dark value that is a relatively low luminance value, corresponding to data of high existence frequency based on the histogram; and a light value arithmetic means for obtaining a light value that is a relatively high luminance value, corresponding to data of low existence frequency based on the dark value, the average value and the existence ratio. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
