User:Ramirez

Image Registration Components

Image Similarity Metrics

• Mutual Information

Tuning Parameters

itk::RegularStepGradientDescentOptimizer->SetScales()

The rule of thumb is to figure out how much each one of those parameters will change for your registration, and then rescale that range to [-1:1].

For example,

if you are doing 2D rigid you will have a 2D transform with three parameters:

     Tx  translation in millimeters along X
     Ty  translation in millimeters along Y
     R   rotation in radians

and you anticipate that your images need a correction of the order of 10 to 50 millimeters in translation and 0.01 to 0.1 radians in rotation, then you should put scales:

     scale[0] = 1/50;     scale for Tx
     scale[1] = 1/50;     scale for Ty
     scale[2] = 1/0.1;    scale for Rotation

Of course, those will be just "good values to start with". You will still need to refine them according to the behavior of the optimizer.

http://public.kitware.com/pipermail/insight-users/2005-April/012896.html

Use Cases

PET-CT Registration

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