Difference between revisions of "CT x-ray scanner"

From Noah.org
Jump to navigationJump to search
Line 22: Line 22:
 
|-
 
|-
 
| [[image:section_4_3.png]] || [[image:section_4_2.png]] || [[image:section_4_1.png]]
 
| [[image:section_4_3.png]] || [[image:section_4_2.png]] || [[image:section_4_1.png]]
|  
+
|}
Add (overlay) the four
+
 
1D radial sections
+
Add (overlay) the four 1D radial sections together to get the CAT image.
together to get the
+
  [[image:section_4_0.png]]+[[image:section_4_3.png]]+[[image:section_4_2.png]]+[[image:section_4_1.png]]=[[image:target_4_out.png]]
  image on the right
 
|| [[image:target_4_out.png]]
 
}
 

Revision as of 09:05, 13 December 2007

CAT Scanning

Here are some sample images that illustrate the process. The algorithm is quite simple.

In a real CAT Scan system the 1 dimensional slices would be taken from the horizontal row of a series of x-rays. In this demo I don't yet have the x-rays to work with so I synthesize the 1D bands from the target image that I want to regenerate. So given a target image I generate a series of 1D radial slices by rotating the target image and then averaging all values in the rows of the image. Then I rotate the slice back to the original angle.

Slices are synthesized from a 180 degree rotation of the target image.

Relative position of each scan slice
The target and four
1-dimensional sections.
The position of the
sections corresponds to
the angle of projection.
target.png section 4 0.png
section 4 3.png section 4 2.png section 4 1.png

Add (overlay) the four 1D radial sections together to get the CAT image.

section 4 0.png+section 4 3.png+section 4 2.png+section 4 1.png=target 4 out.png