Patent ID: 8723866
Filing Date: 2014-05-13
Classification: G06T

Abstract:
1. A method of adaptive direct volume rendering, comprising: fragmenting a sampled 3-D dataset of a scalar field into a plurality of sub-volumes of different sizes, each sub-volume associated with a set of data value parameters characterizing the data value distribution of the scalar field within the sub-volume; defining an opacity transfer function that is dependent upon data values of the scalar field and an illumination model; selectively casting a plurality of rays from a 2-D image plane towards the sampled dataset using a computer processor, each ray having an initial ray energy and a cross-section; for each ray cast from a selected location on the 2-D image plane, estimating pixel values at other locations on the 2-D image plane using the pixel values at the selected locations wherein the step of estimating the ray energy reflected by each sub-volume of the subset includes; wherein if the sub-volume is a smallest sub-volume comprising 2×2×2 3-D cells, the smaller sub-volume is a 3-D cell within the smallest sub-volume, and if the opacity transfer function varies monotonically within the cell and an iso-surface exist in the 3-D cell, the maximum energy differential of the 3-D cell is calculated using the eight data values at the corners of the 3-D cell and the opacity transfer function.