Multi-boundary cardiac data visualization based on multidimensional transfer function with ray distance

A crucial role during the implementation of volume visualization is to identify the optimal transfer function, since the vital information and structure can be highlighted and revealed. The boundary of the volume is shared by respective portion of the two materials formed out of it, which causes undesirable thickening and ambiguity of the boundary explored via traditional LH (Low and High) histogram. To address this issue, initially a modified LH histogram construction method is introduced to intuitively and conveniently visualize cardiac volume for user interaction. Subsequently, the f-LH histogram is presented to further identify and visualize each portion of the boundary accurately. An appropriate multidimensional transfer function generation is proposed by using variables in f-LH space and spatial information, for visualizing the multi-boundary cardiac volume data.