From Ohm

Direct Vs Indirect Methods

Direct vs. Indirect Volume Visualization Methods:

Direct Method: Direct Volume Rendering is the reversal of the scanning process: It used the stack of images to produces a virtual X-Ray image for a particular point of view.

Indirect Method: An iso surface is the set of points ot the data set that have the same iso value. The point set forms a closed surface, which can be extracted and represented by a triangle mesh. This procedure is called iso surface extraction.

DVR absorption rendering (left), isosurface extraction by Marching Cubes Algorithm (right):

Angio-VR vs. Angio-IsoSurface

Advantages of DVR:

Disadvantage of DVR:

Advantages of iso surfaces:

Disadvantages of iso surfaces:

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Page last modified on November 14, 2013, at 12:03 PM