1. A method of generating an automatic object display of volumetric Computed Tomography (CT) data representing one or more objects and reconstructed from x-ray projection data acquired from x-ray detectors for on-screen threat resolution, wherein a label image defining each object as a plurality of voxels of said volumetric CT data is also provided, and wherein said label image contains at least one object, the method comprising: A. Processing said volumetric CT data and said label image and obtaining visualization parameters for each object, wherein the visualization parameters for each object include at least an opening plane and an orientation vector normal to the opening plane; B. Automatically generating at least one display image with respect to a selected object using the corresponding visualization parameters, wherein automatically generating at least one display image comprises (i) rotating the bag according to said orientation vector to optimally align the selected object to operators viewing the object display so as to define an optimally aligned and virtually opened 3D bag image, (ii) removing the front portion of the bag image according to said opening plane, and (iii) rendering the optimally aligned and virtually opened 3D bag image into a display image; and C. Displaying each automatically generated display image from Step B on a display device for on-screen threat resolution.