An image display system comprising: an object device being moved, the object device being an aircraft, a motor vehicle, or a watercraft, wherein the object device is remotely controlled by a user; an image capturing device comprising a camera configured to capture an omnidirectional image or a wide-angle image as a camera image, a first sensor unit configured to detect a posture angle of the camera, a first posture angle calculation unit configured to calculate a first quaternion (q c) indicating the posture angle of the camera, and a first communication unit configured to transmit the camera image and the first quaternion (q c) to an image processing device, the image capturing device being mounted on the object device; a display device that is configured to be used while being fixed to a head or a face of the user, and to display a display image; a head motion tracking device comprising a second sensor unit configured to detect a posture angle of the head of the user, a second posture angle calculation unit configured to calculate a second quaternion (q h) indicating the posture angle of the head of the user, and a second communication unit configured to transmit the second quaternion (q h) to the image processing device; and the image processing device comprising: a third communication unit that is configured to receive the second quaternion (q h) from the head motion tracking device, to receive the camera image and the first quaternion (q c) from the image capturing device, and to transmit the display image to the display device; and an image rendering processor that is configured to correct the second quaternion (q h) using the first quaternion (q c) and to generate the display image by clipping a region from the camera image depending on the corrected second quaternion (q h *), wherein each of the first quaternion (q c) and the second quaternion (q h) consists of a vector indicating an axis of rotation and a scalar indicating an angle of rotation, wherein the corrected second quaternion (q h *) is determined by multiplying the second quaternion (q h) by a multiplicative inverse of the first quaternion (q c) from the left hand, and wherein each of the first and second quaternion use the same reference coordinate system. an object device being moved, the object device being an aircraft, a motor vehicle, or a watercraft, wherein the object device is remotely controlled by a user; an image capturing device comprising a camera configured to capture an omnidirectional image or a wide-angle image as a camera image, a first sensor unit configured to detect a posture angle of the camera, a first posture angle calculation unit configured to calculate a first quaternion (q c) indicating the posture angle of the camera, and a first communication unit configured to transmit the camera image and the first quaternion (q c) to an image processing device, the image capturing device being mounted on the object device; a display device that is configured to be used while being fixed to a head or a face of the user, and to display a display image; a head motion tracking device comprising a second sensor unit configured to detect a posture angle of the head of the user, a second posture angle calculation unit configured to calculate a second quaternion (q h) indicating the posture angle of the head of the user, and a second communication unit configured to transmit the second quaternion (q h) to the image processing device; and the image processing device comprising: a third communication unit that is configured to receive the second quaternion (q h) from the head motion tracking device, to receive the camera image and the first quaternion (q c) from the image capturing device, and to transmit the display image to the display device; and an image rendering processor that is configured to correct the second quaternion (q h) using the first quaternion (q c) and to generate the display image by clipping a region from the camera image depending on the corrected second quaternion (q h *), a third communication unit that is configured to receive the second quaternion (q h) from the head motion tracking device, to receive the camera image and the first quaternion (q c) from the image capturing device, and to transmit the display image to the display device; and an image rendering processor that is configured to correct the second quaternion (q h) using the first quaternion (q c) and to generate the display image by clipping a region from the camera image depending on the corrected second quaternion (q h *), wherein each of the first quaternion (q c) and the second quaternion (q h) consists of a vector indicating an axis of rotation and a scalar indicating an angle of rotation, wherein the corrected second quaternion (q h *) is determined by multiplying the second quaternion (q h) by a multiplicative inverse of the first quaternion (q c) from the left hand, and wherein each of the first and second quaternion use the same reference coordinate system.