摘要 |
A method and apparatus for three dimensional (3D) computerized tomographic (CT) imaging of an object, wherein image reconstruction processing is applied to a plurality of sets of 2D cone beam projection data, each set being acquired on a 2D detector at a corresponding plurality of scan path source positions. A first image reconstruction processing step comprises applying a mask to each set of the projection data so that data inside the boundaries of each mask form a corresponding plurality of masked 2D data sets. Next, the data inside each masked 2D data set is processed along line segments formed in the masked 2D data set, and having their endpoints determined by the mask boundaries, to develop a first 2D estimate of data determined from a given set of the 2D cone beam projection data. The next step comprises developing 2D correction data for each of the first 2D estimates of data by by perfoming a one-dimensional (1D) convolving process.on portions of the masked projection data to develop said 2D correction data. The final step comprises combining each of the first estimates of data and the 2D correction data calculated therefore, in a process which reconstructs an exact 3D image of the object. |