Ray-casting time-varying volume data sets with frame-to-frame coherence

Abstract

The goal of this paper is the proposal and evaluation of a ray-casting strategy that takes advantage of the spatial and temporal coherence in image-space as well as in object-space in order to speed up rendering. It is based on a double structure: in image-space, a temporal buffer that stores for each pixel the next instant of time in which the pixel must be recomputed, and in object-space a Temporal Run-Length Encoding of the voxel values through time. The algorithm skips empty and unchanged pixels through three different space-leaping strategies. It can compute the images sequentially in time or generate them simultaneously in batch. In addition, it can handle simultaneously several data modalities. Finally, an on-purpose out-of-core strategy is used to handle large datasets. The tests performed on two medical datasets and various phantom datasets show that the proposed strategy significantly speeds-up rendering.

A Novel Ray-Casting Algorithm Using Dynamic Adaptive Sampling

“…Luo et al [14] proposed a rendering algorithm based on the height field [15] and an improved algorithm of finding the intersection of isosurfaces to solve the problem of the slow speed of finding the intersection of light and volume data. However, because the volume data will be imaged many times due to the reflection of the surface of the object, so it needs to do many volume data rendering operations, which hurt the performance of the algorithm.…”

“…Tao et al [19] proposed a ray projecting algorithm combining the fitness estimation based on ray-casting with the global optimization method of improved adaptive differential evolution. This method eliminated the fine registration step of the famous iterative nearest point (ICP) algorithm [15,20,21], and it is the first direct global registration algorithm.…”

Interactive HDR lighting of dynamic participating media

“…Li, Mueller and Kaufman's [26] empty space skipping technique avoids sampling areas that contain no data. Spatial and temporal data coherence is exploited in [44] and [21]. All these techniques set up acceleration structures in a precomputation step.…”