1. A method of processing image data comprising: rotating at least one of a template and the image data to adjust a relative angle between an original orientation of the template and an original orientation of the image data to exclude an angle range including 180 degrees, the template being previously provided in a storage and used in detecting a human face; examining a matching between a part of the image data and the template to identify a region in the image data containing an image of the human face; correcting the image data in accordance with a condition of the image of the human face; detecting angle information contained in the image data and indicative of an orientation of an image capturing device when an image in the image data is captured; and determining the relative angle based on the angle information, wherein at least one of rotating, examining, and correcting is performed by an image processor.