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LBPM/analysis/imfilter.h

160 lines
8.8 KiB
C++

// These functions mimic the behavior of imfilter in MATLAB
#ifndef included_imfilter
#define included_imfilter
#include "common/Utilities.h"
#include "common/Array.h"
#include <vector>
namespace imfilter {
//! enum to store the BC type
enum class BC { fixed=0, symmetric=1, replicate=2, circular=3 };
/*!
* @brief N-D filtering of multidimensional images
* @details imfilter filters the multidimensional array A with the
* multidimensional filter H. The result B has the same size and class as A.
* @param[in] A The input array (Nx,Ny,Nz)
* @param[in] H The filter (2*Nhx+1,2*Nhy+1,...)
* @param[in] boundary The boundary conditions to apply (ndim):
* fixed - Input array values outside the bounds of the array are
* implicitly assumed to have the value X
* symmetric - Input array values outside the bounds of the array are
* computed by mirror-reflecting the array across the array border
* replicate - Input array values outside the bounds of the array are
* assumed to equal the nearest array border value
* circular - Input array values outside the bounds of the array are
* computed by implicitly assuming the input array is periodic.
* @param[in] X The value to use for boundary conditions (only used if boundary==fixed)
*/
template<class TYPE>
Array<TYPE> imfilter( const Array<TYPE>& A, const Array<TYPE>& H, const std::vector<imfilter::BC>& boundary, const TYPE X=0 );
/*!
* @brief N-D filtering of multidimensional images
* @details imfilter filters the multidimensional array A with the
* multidimensional filter H. The result B has the same size and class as A.
* @param[in] A The input array (Nx,Ny,Nz)
* @param[in] Nh The size of the filter
* @param[in] H The filter function to use ( y = H(data) )
* Note that the data passed to this function will be of size 2*Nh+1
* @param[in] boundary The boundary conditions to apply (ndim):
* fixed - Input array values outside the bounds of the array are
* implicitly assumed to have the value X
* symmetric - Input array values outside the bounds of the array are
* computed by mirror-reflecting the array across the array border
* replicate - Input array values outside the bounds of the array are
* assumed to equal the nearest array border value
* circular - Input array values outside the bounds of the array are
* computed by implicitly assuming the input array is periodic.
* @param[in] X The value to use for boundary conditions (only used if boundary==fixed)
*/
template<class TYPE>
Array<TYPE> imfilter( const Array<TYPE>& A, const std::vector<int>& Nh,
std::function<TYPE(const Array<TYPE>&)> H,
const std::vector<imfilter::BC>& boundary, const TYPE X=0 );
/*!
* @brief N-D filtering of multidimensional images
* @details imfilter filters the multidimensional array A with the
* multidimensional filter H. The result B has the same size and class as A.
* This version works with separable filters and is more efficient than a single filter.
* @param[in] A The input array (Nx,Ny,Nz)
* @param[in] H The filter [2*Nhx+1,2*Nhy+1,...]
* @param[in] boundary The boundary conditions to apply (ndim):
* fixed - Input array values outside the bounds of the array are
* implicitly assumed to have the value X
* symmetric - Input array values outside the bounds of the array are
* computed by mirror-reflecting the array across the array border
* replicate - Input array values outside the bounds of the array are
* assumed to equal the nearest array border value
* circular - Input array values outside the bounds of the array are
* computed by implicitly assuming the input array is periodic.
* @param[in] X The value to use for boundary conditions (only used if boundary==fixed)
*/
template<class TYPE>
Array<TYPE> imfilter_separable( const Array<TYPE>& A, const std::vector<Array<TYPE>>& H,
const std::vector<imfilter::BC>& boundary, const TYPE X=0 );
/*!
* @brief N-D filtering of multidimensional images
* @details imfilter filters the multidimensional array A with the
* multidimensional filter H. The result B has the same size and class as A.
* This version works with separable filters and is more efficient than a single filter.
* @param[in] A The input array (Nx,Ny,Nz)
* @param[in] H The filter [2*Nhx+1,2*Nhy+1,...]
* @param[in] boundary The boundary conditions to apply (ndim):
* fixed - Input array values outside the bounds of the array are
* implicitly assumed to have the value X
* symmetric - Input array values outside the bounds of the array are
* computed by mirror-reflecting the array across the array border
* replicate - Input array values outside the bounds of the array are
* assumed to equal the nearest array border value
* circular - Input array values outside the bounds of the array are
* computed by implicitly assuming the input array is periodic.
* @param[in] X The value to use for boundary conditions (only used if boundary==fixed)
*/
template<class TYPE>
Array<TYPE> imfilter_separable( const Array<TYPE>& A, const std::vector<int>& Nh,
std::vector<std::function<TYPE(const Array<TYPE>&)>> H,
const std::vector<imfilter::BC>& boundary, const TYPE X=0 );
/*!
* @brief N-D filtering of multidimensional images
* @details imfilter filters the multidimensional array A with the
* multidimensional filter H. The result B has the same size and class as A.
* This version works with separable filters and is more efficient than a single filter.
* @param[in] A The input array (Nx,Ny,Nz)
* @param[in] H The filter [2*Nhx+1,2*Nhy+1,...]
* @param[in] boundary The boundary conditions to apply (ndim):
* fixed - Input array values outside the bounds of the array are
* implicitly assumed to have the value X
* symmetric - Input array values outside the bounds of the array are
* computed by mirror-reflecting the array across the array border
* replicate - Input array values outside the bounds of the array are
* assumed to equal the nearest array border value
* circular - Input array values outside the bounds of the array are
* computed by implicitly assuming the input array is periodic.
* @param[in] X The value to use for boundary conditions (only used if boundary==fixed)
*/
template<class TYPE>
Array<TYPE> imfilter_separable( const Array<TYPE>& A, const std::vector<int>& Nh,
std::vector<std::function<TYPE(int, const TYPE*)>> H,
const std::vector<imfilter::BC>& boundary, const TYPE X=0 );
/**
* @brief Create a filter to use with imfilter
* @details This function creates one of several predefined filters
* to use with imfilter. The filter will always sum to 1.
* Note: this function allocates memory with the new command, the user must call delete.
*
* @param[in] N The stencil size in each direction
* @param[in] type The type of filter to create
* average - Simple averaging filter
* gaussian - Gaussian filter with given standard deviation.
* Optional argument is a double array of size ndim
* giving the standard deviation in each direction.
* A default value of 0.5 is used if not provided.
* \param[in] args An optional argument that some of the filters use
*/
template<class TYPE>
Array<TYPE> create_filter( const std::vector<int>& N, const std::string &type, const void *args = NULL );
}
#include "analysis/imfilter.hpp"
#endif