Assignment 3- Visualization of 3D Volumetric Structures from Medical Images
Submitted by: Chandrasekaran Indhumathi
G0300922J
Algorithm: Maximum Intensity Projection
Link to the data set you have used:
Human foot
http://radiology.uiowa.edu/downloads/
Summary of the data set:
Dimension: 160*430*180
File type : Img file (hdr file)
Source
: 31 yr. old male
Visualization software used: MRIcro
Written in c
Description:
Method: Maximum Intensity Projection
Images are shown in axial, sagittal
and frontal view. Maximum intensity
projection of the human foot shows
the bone inside the tissue very
clearly.
Adjustments made:
i) Air threshold value -10
ii) Maximum Intensity projection
iii) Color scheme for slice viewer is
set to BONE
Description:
Method: MIP with High Air threshold
Images are shown in axial, sagittal
and frontal view. Air/threshold
value is set to 100. The tissues are
removed and the bone of the foot
alone is made visible. Enhanced
contrast of bones.
Adjustments made:
i) Air threshold value -100
ii) Maximum Intensity projection
iii) Color scheme for slice viewer is
set to BONE
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Algorithm: Volume rendering-Ray Casting
Link to the data set you have used:
Frog dataset
ftp://public.kitware.com/pub/vtk/
Summary of the data set:
Size in voxels
: 500*470*138
Physical size
:499*469*137
Sample spacing :1.00*1.00*1.00
Data Origin
: 0.00,0.00,0.00
Scalar Ranges :0. 000 to 254.00
Visualization software used: Volview from
VTK http://kitware.com
Description:
Ray casting is a technique to render 3D
graphics on a 2D screen. It uses
backward mapping technique to render
the volumetric data. It determines the
voxel values encountered along the ray
and process these values according to
ray function.
Adjustments made:
i) Background color
ii) Scalar opacity mapping
iii) Scalar color mapping
iv)Contrast
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Algorithm: Volume rendering-Marching
Cubes
Link to the data set you have used:
Human Head Dataset
Data source: Volvis data sample
Visualization software used: Volvis
(a) Rendering by Marching Cube algorithm
Summary of the data set:
File Type
:Slice File
Data Size
:59 x 133 x 133 voxels
Voxel Size
:2.064x1.376x 1.376mm
Data Origin
:Voxelized Function File
Data Modification :Original Data
Data Compression :Run Length Encoding
(b) Rendering by Ray tracing algorithm
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Algorithm: Countering
Link to the data set you have used:
Summary of the data set:
Half Head Dataset : -Volview data sample.
Lobster Dataset :-Volvis data sample
Half Human Head:
Size in voxels
: 128*128*93
Physical size
:203*203*138(mm)
Sample spacing :1.60*1.60*1.50(mm)
Data Origin
: -203.20,0.00,-138.00
Data Type
:Unsigned Short
Scalar Ranges :0. 000 to 4095.00
Visualization software used: Volview2.0
http://kitware.com
Lobster:
File Type
Image Size
Accuracy
Image Time
Contouring is a scalar visualization technique that
constructs boundary between regions on different
data values with surfaces of contrast scalar values.
MRI data slices are stacked to form volume by ray
casting technique. Contour are drawn by setting
the isovalue at 957.54 on the rendered image.
:Image File
: 300 x 300 pixels
RGB Color Image
:Progressive
: 6.625000
Contours are drawn by setting the isosurface
value at 57.40.
4
Algorithm: Surface Rendering
Link to the data set you have used:
Human Brain –MRI Data sample of MRIcro
Summary of the data set:
Dimension
: 181*217*181
File type
: Img file (hdr file)
Slice thickness :1mm
Visualization software used: MRIcro
Written in c
Description:
Surface rendered image of Human
brain. Multiple slices of MRI images
are stacked together to get the 3D
image of Brain. Images are shown
in axial, sagittal and frontal view.
Surface rendering is by far the most
popular approach to rendering objects.
Color scheme for slice viewer is set
to GOLD.
Air/Surface threshold value is set to
100. A high air/surface threshold is
required to show nice sulcal definition in
the surface renderings. However, at
these high values the gray matter has
been stripped from the image. Color
scheme for slice viewer is set to
GOLD.
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