Patent ID: 7561195

Claim:
An image sensing apparatus that outputs an image of an object, comprising: an image sensing device including a photoelectric conversion element that photoelectrically converts an optical image to acquire image data, and a readout control unit that reads out, in accordance with a supplied readout rule, the image data acquired by the photoelectric conversion element; an image scaling ratio selection unit that selects a scaling ratio of the image to be output; a readout scheme selection unit that selects, in accordance with the selected image scaling ratio, a readout scheme of the image data to be read out from the photoelectric conversion element by the readout control unit; and a readout rule supply unit that supplies, to the readout control unit, a readout rule corresponding to the readout scheme selected by the readout scheme selection unit; wherein a thinning readout mode is selectable as the readout scheme by the readout scheme selection unit, and an image signal output from the image sensing device includes a plurality of frames; and wherein the image sensing apparatus further comprises: a distortion correction unit that executes distortion correction for the image signal output from the image sensing device in the thinning readout mode; a readout phase control unit that changes, for each frame, a reference position of an area of the image data to be read out from the photoelectric conversion element by the readout control unit in the thinning readout mode; and an image area selection processing unit that selects an area of a region common to all frames of the corrected image signal output from the distortion correction unit based on the reference position of the readout area that is changed for each frame by the readout phase control unit in the thinning readout mode.