Abstract: A computer program for manipulating diagnostic images obtained with computed tomography or magnetic resonance systems spatially compresses acquired non-isotropic data to isotropic coordinates as stored in computer memory. A view axis along which a projected image is to be displayed is adjusted to reflect this distortion. After projecting the voxel data to pixels of an image, the data is decompressed to remove any distortion. The decompression operates over the limited number of pixels rather than the entire set of voxels providing faster image generation.

Abstract: A method and apparatus for manipulating diagnostic images obtained with computed tomography or magnetic resonance systems calculates the rotation of the data around two orthogonal axes and then compresses the data to a plane before rotating it about a third axis normal to the plane. Although apparently less efficient that the rotation about all three axes at once, this procedure is uniquely adapted to the limitations of computer memory access and the calculation speed limits of current computer hardware. Bifurcation of the rotation allows data to be accessed at consecutive addresses speeding memory operations. The bifurcation also permits some calculations to be preperformed and recalled for subsequent voxels. The compressed data is displayed as an image having a particular viewing angle determined by the rotations of the data.

Abstract: A computer program for manipulating diagnostic images obtained with computed tomography or magnetic resonance systems stores acquired voxel data in addresses in an electronic memory related to the spatial location of the voxels. Sample lines are identified in the space of the voxels and interpolated values are determined for points along these sample lines by accessing the volume data in the electronic memory as a "tube" which includes voxel data having spatial coordinates which vary only in the dimension of the sample line. The tube of data may be more easily accessed from the electronic memory than would a series of random accesses and also allows the sharing of interpolation calculations for the interpolated points along the sample lines.