Patent ID: 8416913

Claim:
An X-ray computed tomography (CT) system, comprising: an X-ray tube configured to irradiate an X-ray; an X-ray detector situated so as to face the X-ray tube and configured to detect the X-ray having passed through an object; a scan controller configured to scan the object by rotating the X-ray tube and the X-ray detector around the object in order to obtain X-ray transmission data by means of the X-ray tube and the X-ray detector, the X-ray transmission data including an entire contour of the object; an outline calculator configured to calculate an outline of the object from the X-ray transmission data; a correction part configured to correct a distortion of the entire contour of the object indicated by the X-ray transmission data based on the outline calculated by the outline calculator; and a reconstructing part configured to reconstruct image data of an inside of the object based on the X-ray transmission data corrected by the correction part, wherein the outline calculator includes a converter configured to execute fan-parallel conversion on the X-ray transmission data obtained by the scan controller; an extracting part configured to extract X-ray transmission data of two specific directions orthogonal to each other from the X-ray transmission data to which the fan-parallel conversion is applied; and a calculator configured to calculate the outline of the object by calculating a major diameter, a minor diameter, a shift amount in a major diameter direction, and a shift amount in a minor diameter direction of the object based on the X-ray transmission data of the two specific directions, wherein the calculator is configured to weight and normalize the major diameter, the minor diameter, the shift amount in the major diameter direction, and the shift amount in the minor diameter direction at each tomographic position at which the outline is calculated based on distances between each tomographic position at which the outline is calculated and a tomographic position at which the outline is to be interpolated, in order to interpolate the outline.