In the invention, a particular-region such as red-eye region of a photographed image is detected, the image including a person as an object. At first a particular region candidate satisfying detection conditions for the particular region candidate is detected from the image. Then, a face region of the person satisfying detection conditions for the face region of the person is detected and the particular region candidate is specified as a particular region to be detected, in a condition that the particular region candidate is included in the detected face region. On the other hand, the image is divided into first and second regions at least before the detecting of the face region of the person. The detection conditions used for the detection for the particular region candidate or the detection for the face region of the person are changed between the first region and the second region of the image.