NumCpp  2.10.1
A Templatized Header Only C++ Implementation of the Python NumPy Library
mirror2d.hpp
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1 #pragma once
29 
31 #include "NumCpp/Core/Shape.hpp"
32 #include "NumCpp/Core/Slice.hpp"
33 #include "NumCpp/Core/Types.hpp"
35 #include "NumCpp/NdArray.hpp"
36 
37 namespace nc::filter::boundary
38 {
39  //============================================================================
40  // Method Description:
47  template<typename dtype>
48  NdArray<dtype> mirror2d(const NdArray<dtype>& inImage, uint32 inBoundarySize)
49  {
51 
52  const Shape inShape = inImage.shape();
53  Shape outShape(inShape);
54  outShape.rows += inBoundarySize * 2;
55  outShape.cols += inBoundarySize * 2;
56 
57  NdArray<dtype> outArray(outShape);
58  outArray.put(Slice(inBoundarySize, inBoundarySize + inShape.rows),
59  Slice(inBoundarySize, inBoundarySize + inShape.cols),
60  inImage);
61 
62  for (uint32 row = 0; row < inBoundarySize; ++row)
63  {
64  // bottom
65  outArray.put(row,
66  Slice(inBoundarySize, inBoundarySize + inShape.cols),
67  inImage(inBoundarySize - row, Slice(0, inShape.cols)));
68 
69  // top
70  outArray.put(row + inBoundarySize + inShape.rows,
71  Slice(inBoundarySize, inBoundarySize + inShape.cols),
72  inImage(inShape.rows - row - 2, Slice(0, inShape.cols)));
73  }
74 
75  for (uint32 col = 0; col < inBoundarySize; ++col)
76  {
77  // left
78  outArray.put(Slice(inBoundarySize, inBoundarySize + inShape.rows),
79  col,
80  inImage(Slice(0, inShape.rows), inBoundarySize - col));
81 
82  // right
83  outArray.put(Slice(inBoundarySize, inBoundarySize + inShape.rows),
84  col + inBoundarySize + inShape.cols,
85  inImage(Slice(0, inShape.rows), inShape.cols - col - 2));
86  }
87 
88  // now fill in the corners
89  NdArray<dtype> lowerLeft =
90  flipud(outArray(Slice(inBoundarySize + 1, 2 * inBoundarySize + 1), Slice(0, inBoundarySize)));
91  NdArray<dtype> lowerRight = flipud(outArray(Slice(inBoundarySize + 1, 2 * inBoundarySize + 1),
92  Slice(outShape.cols - inBoundarySize, outShape.cols)));
93 
94  const uint32 upperRowStart = outShape.rows - 2 * inBoundarySize - 1;
95  NdArray<dtype> upperLeft =
96  flipud(outArray(Slice(upperRowStart, upperRowStart + inBoundarySize), Slice(0, inBoundarySize)));
97  NdArray<dtype> upperRight = flipud(outArray(Slice(upperRowStart, upperRowStart + inBoundarySize),
98  Slice(outShape.cols - inBoundarySize, outShape.cols)));
99 
100  outArray.put(Slice(0, inBoundarySize), Slice(0, inBoundarySize), lowerLeft);
101  outArray.put(Slice(0, inBoundarySize), Slice(outShape.cols - inBoundarySize, outShape.cols), lowerRight);
102  outArray.put(Slice(outShape.rows - inBoundarySize, outShape.rows), Slice(0, inBoundarySize), upperLeft);
103  outArray.put(Slice(outShape.rows - inBoundarySize, outShape.rows),
104  Slice(outShape.cols - inBoundarySize, outShape.cols),
105  upperRight);
106 
107  return outArray;
108  }
109 } // namespace nc::filter::boundary
#define STATIC_ASSERT_ARITHMETIC(dtype)
Definition: StaticAsserts.hpp:39
Holds 1D and 2D arrays, the main work horse of the NumCpp library.
Definition: NdArrayCore.hpp:138
self_type & put(index_type inIndex, const value_type &inValue)
Definition: NdArrayCore.hpp:3616
Shape shape() const noexcept
Definition: NdArrayCore.hpp:4402
A Shape Class for NdArrays.
Definition: Core/Shape.hpp:41
uint32 rows
Definition: Core/Shape.hpp:44
uint32 cols
Definition: Core/Shape.hpp:45
A Class for slicing into NdArrays.
Definition: Slice.hpp:45
Definition: addBoundary1d.hpp:44
NdArray< dtype > mirror2d(const NdArray< dtype > &inImage, uint32 inBoundarySize)
Definition: mirror2d.hpp:48
NdArray< dtype > flipud(const NdArray< dtype > &inArray)
Definition: flipud.hpp:46
std::uint32_t uint32
Definition: Types.hpp:40