| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a technique for enabling an image of good image quality to be obtained even if pixel position correction relating to keystone correction is performed. <P>SOLUTION: A CPU 101 generates an inverse projection image by performing, for an input image, inverse projection transformation using the inverse matrix of a projection transformation matrix for enlarging the size of the input image. When a target pixel position on the input image is transformed into a target inverse projection pixel position on the inverse projection image by the inverse projection transformation, the CPU calculates the ratio of a distance between pixels around the target inverse projection pixel position to a distance between pixels around the target pixel position. The CPU calculates filter coefficients of a low-pass filter whose cutoff frequency is a product of the Nyquist frequency of the input image and the ratio. The CPU calculates the sum of results obtained by multiplying the pixel values of respective pixels in a pixel array including the target pixel position in the input image by the respective low-pass filter coefficients as the pixel value at the target pixel position in a filter-processed image. <P>COPYRIGHT: (C)2012,JPO&INPIT |
