Line 39: Line 39:
  
 
* Define the counter-clockwise rotation matrix
 
* Define the counter-clockwise rotation matrix
 +
 +
the matrix rotates vector <math>v_0</math> in a 2-D real space by angle <math>\theta</math> in a fixed coordinate system.
  
 
<math>\begin{bmatrix}
 
<math>\begin{bmatrix}
Line 75: Line 77:
  
 
* C. A. Bouman. ECE 637. Class Lecture. Digital Image Processing I. Faculty of Electrical Engineering, Purdue University. Spring 2013.
 
* C. A. Bouman. ECE 637. Class Lecture. Digital Image Processing I. Faculty of Electrical Engineering, Purdue University. Spring 2013.
 +
 +
* E. W. Weisstein, "Rotation Matrix." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/RotationMatrix.html. May 8th, 2013 [May 21st, 2013]
  
  

Revision as of 13:02, 21 May 2013

sLecture

Topic 2: Tomographic Reconstruction
Intro
CT
PET
Co-ordinate Rotation


The Bouman Lectures on Image Processing

A sLecture by Maliha Hossain

Subtopic 3: Co-ordinate Rotation

© 2013




Excerpt from Prof. Bouman's Lecture


Accompanying Lecture Notes


  • Define the counter-clockwise rotation matrix

the matrix rotates vector $ v_0 $ in a 2-D real space by angle $ \theta $ in a fixed coordinate system.

$ \begin{bmatrix} \cos(\theta) & -\sin(\theta) \\ \sin(\theta) & \cos(\theta) \end{bmatrix} $

  • Define the new coordinate system $ (r,z) $

$ \begin{bmatrix} x \\ y \end{bmatrix} = A_{\theta}\begin{bmatrix} r \\ z \end{bmatrix} $


Fig 1: Geometric Interpretation


  • Inverse Transformation

$ \begin{bmatrix} r \\ z \end{bmatrix} = A_{-\theta}\begin{bmatrix} x \\ y \end{bmatrix} $


References

  • C. A. Bouman. ECE 637. Class Lecture. Digital Image Processing I. Faculty of Electrical Engineering, Purdue University. Spring 2013.



Questions and comments

If you have any questions, comments, etc. please post them on this page



Back to the "Bouman Lectures on Image Processing" by Maliha Hossain

Alumni Liaison

Ph.D. on Applied Mathematics in Aug 2007. Involved on applications of image super-resolution to electron microscopy

Francisco Blanco-Silva