Abstract: A method and apparatus for generating a two-dimensional output image of a slab multi-planar reformatting (MPR) volume data set from a selectable view point and view direction is described. The method comprises factorising a view transform matrix into an intermediate transform matrix and a warp transform matrix. The intermediate transform matrix is such that voxels in the volume data set map to pixels in an intermediate image in which neighbouring voxels in a plane of the volume data set which is most parallel to tie plane of the output image are separated by an integer number of pixel along each of tie axes of the intermediate image. The intermediate transform matrix is applied to the data set to provide an intermediate data set. A projection of the intermediate data set along the view direction is performed according to a desired projection algorithm to provide the intermediate image. The wrap transform matrix is then applied to the intermediate image to provide the output image.

Abstract: A computer automated process is presented for accelerating the rendering of sparse volume data on Graphics Processing Units (GPUs). GPUs are typically SIMD processors, and thus well suited to processing continuous data and not sparse data. The invention allows GPUs to process sparse data efficiently through the use of scatter-gather textures. The invention can be used to accelerate the rendering of sparse volume data in medical imaging or other fields.

Abstract: A computer program and a computer-implemented system and method for generating a two-dimensional image of a volume data set representing an object volume from a selectable viewpoint. An object volume data set includes voxel values ordered by voxels along a row that extends in a first direction, rows across a plane that extends in the first direction and a second direction, and planes through an object volume that extend in the first and second directions and a third direction. In response to the definition of a view vector defining a view direction with respect to a viewpoint, shear and warp mappings are determined, as is which of the first, second and third directions is closest to the view vector. Pixels of a two-dimensional sheared image having a plurality of lines of pixels are then determined from voxel values of the object volume data set identified by the shear mapping.

Abstract: A user interface for a computer-implemented Multi-Planar Reformatting (MPR) system comprises three display areas in which are displayed three orthogonal MPR images of the volume data set; a curve drawing tool to allow a user to define a curve through the volume data set; six selectable icons each representing one of six possible combinations of a plane parallel to one of the orthogonal MPR images and a direction substantially normal to a plane parallel to one of the other two MPR images, using which the user selects an approximate direction for the curve; and a fourth display area displaying a curve-related MPR image related to one or more points along the curve. The icons may be individually selectable to allow user input of adequate orientational information for a curved MPR image, or selectable in pairs for input of directional information for a cross-curve MPR image. Alternatively, three icons may be provided for a cross-curve MPR system.

Abstract: A computer automated method for setting visualization parameter boundaries in a preset for displaying an image from a 3D data set applicable to magnetic resonance (MR) data, computer tomography (CT) data and other 3D data sets obtained in medical imaging is described. In one example the visualization parameter boundaries are color boundaries. A histogram of data values of voxels within a user-selected volume of interest (VOI) is generated and an analysis of a convex hull spanning the histogram is made to provide one or more visualization thresholds which divide the histogram into sub-regions. The sub-regions relate to different tissue types within the VOI and color boundaries are set based on the visualization thresholds for displaying the different tissue types in different colors. The method allows color boundaries in a preset to be set objectively and automatically so that images can be displayed consistently and with less user manipulation.