| 摘要 |
PURPOSE:To stably detect the inclination angle of a line or a character even concerning an image, for which a background noise is mixed or a character is not clear, by using a value calculating difference between a maximum value and a minimum value from the total sum as an evaluation amount from a histogram prepared to the predictive inclination angle, and using the value of theta taking the maximum value as the inclination angle. CONSTITUTION:A cumulative black picture element histogram Htheta (x) is calculated in a step 102 by performing precise scanning in the direction of the predictive inclination angle theta, an xi is set to an initial value xs in a step 103, and an evaluation amount Ctheta is set at '0'. In a step 104, the maximum and minimum values of the cumulative black picture element histogram Htheta(x) for a prescribed block are calculated and in a step 105, the evaluation amount Ctheta is defined as a value adding the difference between the maximum and minimum values of the cumulative black picture element histogram H (x) to the initial value of the evaluation amount Ctheta. In a step 106, it is updated into xi=xi+1, and the calculation is repeatedly performed within the prescribed block. Then, the value of theta with the maximum value of the evaluation amount Ctheta calculated like this is used as the inclination angle. |
