Affiliations: Department of Computer Science and Engineering, Seoul
National University, Seoul, Korea | Department of Computer Software Engineering, Sangmyung
University, Seoul, Korea | Department of Computer Science, Sangmyung University,
Seoul, Korea
Note: [] Corresponding author: Yeong-Gil Shin, Department of Computer
Science and Engineering, Seoul National University, 1 Gwanakro, Gwanakgu,
Seoul, Korea. Tel.: +82 2 880 1860; Fax: +82 2 886 7589; E-mail: yshin@snu.ac.kr
Abstract: BACKGROUND: Maximum intensity projection (MIP) is a volume
rendering technique that determines the pixel intensity as the maximum of all
values sampled along the viewing direction. MIP has been successfully applied
to diagnose bone fractures in computed tomography (CT) and the stenosis of
vascular structures in magnetic resonance angiography (MRA). However, MIP has a
major drawback in that the depth and occlusion information cannot be perceived
in the output images. The most universal way to alleviate this problem is to
occasionally change the viewpoint for depth perception. To support this
function in real time, MIP should be performed at an interactive frame rate. OBJECTIVE: We develop an efficient rendering algorithm for MIP so that
MIP is performed at an interactive frame rate without a loss of image quality. METHODS: The proposed method predicts the position of the
maximum intensity for each ray using blockwise maximum bounds, after which it
performs bidirectional compositing toward both ends of the ray from this
predicted position. During the compositing process, block skipping is used as
an acceleration method. RESULTS: The proposed method outperformed the
block skipping method using the sequential compositing with a speed-up factor
of 2.2 ∼ 2.8 depending on the data set without any degradation of the image quality. CONCLUSION: We proposed an efficient rendering technique for
MIP. Our method was superior to the conventional block skipping method with
respect to the rendering speed and degree of performance consistency.
Keywords: Maximum intensity projection, acceleration techniques, prediction of the starting position, bidirectional compositing, block skipping
