Difference between revisions of "Transform"

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For the MIPAV HTML help, please use this link <nowiki>http://mipav.cit.nih.gov/documentation/HTML Algorithms/Transform.html</nowiki>
 
For the MIPAV HTML help, please use this link <nowiki>http://mipav.cit.nih.gov/documentation/HTML Algorithms/Transform.html</nowiki>
== Background ==
 
  
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== Background ==
 
The Transformation algorithm, transforms images (volumes) by resampling the image using transformation matrix and the choice of Nearest-Neighbor, [[Interpolation methods used in MIPAV#Gaussian|Gaussian]], [[Interpolation methods used in MIPAV#Bilinear Interpolation|Bilinear]], [[Interpolation methods used in MIPAV#Trilinear Interpolation|Trilinear]], [[Interpolation methods used in MIPAV#B-spline basis interpolations|3rd order B-spline]], [[Interpolation methods used in MIPAV#B-spline basis interpolations|4th order B-spline]], [[Interpolation methods used in MIPAV#Lagrange interpolations|Cubic Lagrangian]], [[Interpolation methods used in MIPAV#Lagrange interpolations|Quintic Lagrangian]], [[Interpolation methods used in MIPAV#Lagrange interpolations|Heptic Lagrangian]], or [[Interpolation methods used in MIPAV#Windowed sinc|Windowed sinc]].  
 
The Transformation algorithm, transforms images (volumes) by resampling the image using transformation matrix and the choice of Nearest-Neighbor, [[Interpolation methods used in MIPAV#Gaussian|Gaussian]], [[Interpolation methods used in MIPAV#Bilinear Interpolation|Bilinear]], [[Interpolation methods used in MIPAV#Trilinear Interpolation|Trilinear]], [[Interpolation methods used in MIPAV#B-spline basis interpolations|3rd order B-spline]], [[Interpolation methods used in MIPAV#B-spline basis interpolations|4th order B-spline]], [[Interpolation methods used in MIPAV#Lagrange interpolations|Cubic Lagrangian]], [[Interpolation methods used in MIPAV#Lagrange interpolations|Quintic Lagrangian]], [[Interpolation methods used in MIPAV#Lagrange interpolations|Heptic Lagrangian]], or [[Interpolation methods used in MIPAV#Windowed sinc|Windowed sinc]].  
  
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=== Transformation matrix ===
 
=== Transformation matrix ===
 
 
The Transform tab of the dialog box allows the user to transform an image using the transformation matrix that can be either
 
The Transform tab of the dialog box allows the user to transform an image using the transformation matrix that can be either
  
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=== Transform tab ===
 
=== Transform tab ===
  
[[File:TransformationOptions.jpg|300px|thumb|left|Transform tab - transformation options]]
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[[File:TransformationOptions.jpg|400px|thumb|left|Transform tab - transformation options]]
  
 
*No transformation - if selected, this option disables all transformation options, but the interpolation options are still available. Therefore, the user can not perform the transformation, but is still able to run the interpolation for a chosen image.
 
*No transformation - if selected, this option disables all transformation options, but the interpolation options are still available. Therefore, the user can not perform the transformation, but is still able to run the interpolation for a chosen image.
  
==== Transformation options ====
 
  
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==== Transformation options ====
 
*Use image associated matrix - if checked, this option allows using a transformation matrix associated with the image.  
 
*Use image associated matrix - if checked, this option allows using a transformation matrix associated with the image.  
  
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*Sx, Sy, Sz - '''scales''' in the X, Y, and Z directions;  
 
*Sx, Sy, Sz - '''scales''' in the X, Y, and Z directions;  
 
*SKx, SKy, and SKz - '''skews''' in the X, Y, and Z directions.
 
*SKx, SKy, and SKz - '''skews''' in the X, Y, and Z directions.
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==== MIPAV coordinate system and image origin ====
 
==== MIPAV coordinate system and image origin ====
 
In MIPAV, we use the right hand coordinate system. The image origin is located in the upper left had corner on the first image slice. Pay attention to a little diagram next to [[#UserDefined|the user defined transformation matrix]] options.  
 
In MIPAV, we use the right hand coordinate system. The image origin is located in the upper left had corner on the first image slice. Pay attention to a little diagram next to [[#UserDefined|the user defined transformation matrix]] options.  
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[[Category:Help]]
 
[[Category:Help]]
 
[[Category:Help:Stub]]
 
[[Category:Help:Stub]]
 
[[Category:Help:Algorithms]]
 
[[Category:Help:Algorithms]]

Revision as of 14:33, 7 November 2012

This page is a stub.

For the MIPAV HTML help, please use this link http://mipav.cit.nih.gov/documentation/HTML Algorithms/Transform.html

Background

The Transformation algorithm, transforms images (volumes) by resampling the image using transformation matrix and the choice of Nearest-Neighbor, Gaussian, Bilinear, Trilinear, 3rd order B-spline, 4th order B-spline, Cubic Lagrangian, Quintic Lagrangian, Heptic Lagrangian, or Windowed sinc.

The Transform/Resample dialog box provides the user interface for transforming and (or) resampling images. It offers multiple options that help the user to define the transformation matrix and execute the transformation and (or) resampling algorithm. The user is asked to provide the output volume's desired resolutions and dimensions.

The Transform dialog box

To learn more about interpolation techniques used in the method, refer to Interpolation methods used in MIPAV:

Transform dialog box

The dialog box has two tabs - Transform and Resample. The Transform tab allows the user to set up the transformation matrix and choose the interpolation method. The Resample tab is designed to set up the resampling interpolation.

Transformation matrix

The Transform tab of the dialog box allows the user to transform an image using the transformation matrix that can be either

  • A matrix associated with the image,
  • A matrix stored in a separate file,
  • The user defined matrix, defined in this dialog box.

Transform tab

Transform tab - transformation options
  • No transformation - if selected, this option disables all transformation options, but the interpolation options are still available. Therefore, the user can not perform the transformation, but is still able to run the interpolation for a chosen image.


Transformation options

  • Use image associated matrix - if checked, this option allows using a transformation matrix associated with the image.
  • Read matrix from file - if checked, reads the transformation matrix from a file. The user should select the file where the transformation matrix is stored.

User defined transformation matrix

User defined transformation matrix

The options available for defining a transformation matrix are as follows:

  • Tx, Ty, Tz in mm - translations in the X, Y, and Z directions;
  • Rx, Ry, Rz in degrees - rotations along the X, Y, and Z axis;
  • Sx, Sy, Sz - scales in the X, Y, and Z directions;
  • SKx, SKy, and SKz - skews in the X, Y, and Z directions.


MIPAV coordinate system and image origin

In MIPAV, we use the right hand coordinate system. The image origin is located in the upper left had corner on the first image slice. Pay attention to a little diagram next to the user defined transformation matrix options.