ITK/Release 4/Refactor Numerical Libraries/Inventory/Matrix Vector Operations: Difference between revisions
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(Created page with "= Index to Point = The ImageBase class provides the methods: TransformIndexToPhysicalPoint TransformPhysicalPointToIndex These methods perform Matrix x Vector multiplica...") |
Daviddoria (talk | contribs) m (moved ITK Release 4/Refactor Numerical Libraries/Inventory/Matrix Vector Operations to ITK/Release 4/Refactor Numerical Libraries/Inventory/Matrix Vector Operations) |
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These methods perform Matrix x Vector multiplications. | These methods perform Matrix x Vector multiplications. | ||
* The first one converts the integer grid coordinates of a pixel to it s world coordinates in physical space. | |||
* The second method converts th world coordinates in physical space to integer grid coordinates of a pixel. | |||
Internally they use the helper matrices | |||
this->m_IndexToPhysicalPoint | |||
this->m_PhysicalPointToIndex | |||
That are pre-computed in the method: | |||
ComputeIndexToPhysicalPointMatrices() | |||
in lines 178-201 if itkImageBase.hxx | |||
The method | The method | ||
| Line 13: | Line 28: | ||
Is called millions of times during the execution of Image Registration processes. | Is called millions of times during the execution of Image Registration processes. | ||
The actual multiplication is done in the file | |||
ITK/Core/Common/include/itkImageBase.h | |||
in lines: | |||
456 - 480 | |||
Luis to find an example suitable for profiling. Probably based on the ResampleImage*.cxx files in | |||
ITK/Examples/Filtering | |||
but with a 3D input image, so it takes enough computation time to provide reliable benchmarking. | |||
Latest revision as of 16:01, 9 December 2011
Index to Point
The ImageBase class provides the methods:
TransformIndexToPhysicalPoint TransformPhysicalPointToIndex
These methods perform Matrix x Vector multiplications.
- The first one converts the integer grid coordinates of a pixel to it s world coordinates in physical space.
- The second method converts th world coordinates in physical space to integer grid coordinates of a pixel.
Internally they use the helper matrices
this->m_IndexToPhysicalPoint this->m_PhysicalPointToIndex
That are pre-computed in the method:
ComputeIndexToPhysicalPointMatrices()
in lines 178-201 if itkImageBase.hxx
The method
TransformIndexToPhysicalPoint
Is called millions of times during the execution of Image Registration processes.
The actual multiplication is done in the file
ITK/Core/Common/include/itkImageBase.h
in lines:
456 - 480
Luis to find an example suitable for profiling. Probably based on the ResampleImage*.cxx files in
ITK/Examples/Filtering
but with a 3D input image, so it takes enough computation time to provide reliable benchmarking.
