1. An imaging apparatus for correcting inclination of one or more subjects in a captured image by applying a rotational transform to the captured image, the imaging apparatus comprising: an imaging unit operable to capture an image; a sensor operable to detect a physical inclination angle of the imaging unit; an image processing unit operable to determine an angle range that includes the physical inclination angle detected by the sensor when the imaging unit has captured the image and a width determined from measurement errors of the sensor, and then to detect a plurality of angular components in one or more subjects appearing in the image captured by the imaging unit, the plurality of angular components individually falling within the angle range; and a correction processing unit operable to measure a frequency distribution of the plurality of angular components to select one of angular components as a rotation angle for the rotational transform based on the frequency distribution, and then to apply the rotational transform to the image.