  The goal of 3D visualization is to provide the user with an intuitive
interface which enables him to explore the 3D data in an interactive manner.
The aim of the exploration is to identify and analyze anomalies or to give
proof of the non-anomaly of the visualized organic structures. For 3D Medical
Data, Magnetic Resonance Images (MRI) has been used. To create the 3D model, we
used the Direct Volume Rendering technique. In the input 3D data, we have $x,
y$ and $z$ coordinates and an intensity value for each voxel. The 3D data is
used by Volume Ray Casting to compute 2D projections from 3D volumetric data
sets. In ray casting, a ray of light is made to pass through the volume data.
The interaction of each voxel with this ray is used to assign RGB and alpha
values for every voxel in the volume. As a result, we are able to generate the
3D model of the region of interest using the 3D data. The 3D model is
interactive, thus enabling us to visualize the different layers of the 3D
volume by adjusting the transfer function.
