NumCpp  2.8.0
A Templatized Header Only C++ Implementation of the Python NumPy Library
reflect2d.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
38 {
39  namespace filter
40  {
41  namespace boundary
42  {
43  //============================================================================
44  // Method Description:
52  template<typename dtype>
53  NdArray<dtype> reflect2d(const NdArray<dtype>& inImage, uint32 inBoundarySize)
54  {
56 
57  const Shape inShape = inImage.shape();
58  Shape outShape(inShape);
59  outShape.rows += inBoundarySize * 2;
60  outShape.cols += inBoundarySize * 2;
61 
62  NdArray<dtype> outArray(outShape);
63  outArray.put(Slice(inBoundarySize, inBoundarySize + inShape.rows),
64  Slice(inBoundarySize, inBoundarySize + inShape.cols),
65  inImage);
66 
67  for (uint32 row = 0; row < inBoundarySize; ++row)
68  {
69  // bottom
70  outArray.put(row,
71  Slice(inBoundarySize, inBoundarySize + inShape.cols),
72  inImage(inBoundarySize - row - 1, Slice(0, inShape.cols)));
73 
74  // top
75  outArray.put(row + inBoundarySize + inShape.rows,
76  Slice(inBoundarySize, inBoundarySize + inShape.cols),
77  inImage(inShape.rows - row - 1, Slice(0, inShape.cols)));
78  }
79 
80  for (uint32 col = 0; col < inBoundarySize; ++col)
81  {
82  // left
83  outArray.put(Slice(inBoundarySize, inBoundarySize + inShape.rows),
84  col,
85  inImage(Slice(0, inShape.rows), inBoundarySize - col - 1));
86 
87  // right
88  outArray.put(Slice(inBoundarySize, inBoundarySize + inShape.rows),
89  col + inBoundarySize + inShape.cols,
90  inImage(Slice(0, inShape.rows), inShape.cols - col - 1));
91  }
92 
93  // now fill in the corners
94  NdArray<dtype> lowerLeft =
95  flipud(outArray(Slice(inBoundarySize, 2 * inBoundarySize), Slice(0, inBoundarySize)));
96  NdArray<dtype> lowerRight = flipud(outArray(Slice(inBoundarySize, 2 * inBoundarySize),
97  Slice(outShape.cols - inBoundarySize, outShape.cols)));
98 
99  const uint32 upperRowStart = outShape.rows - 2 * inBoundarySize;
100  NdArray<dtype> upperLeft =
101  flipud(outArray(Slice(upperRowStart, upperRowStart + inBoundarySize), Slice(0, inBoundarySize)));
102  NdArray<dtype> upperRight = flipud(outArray(Slice(upperRowStart, upperRowStart + inBoundarySize),
103  Slice(outShape.cols - inBoundarySize, outShape.cols)));
104 
105  outArray.put(Slice(0, inBoundarySize), Slice(0, inBoundarySize), lowerLeft);
106  outArray.put(Slice(0, inBoundarySize),
107  Slice(outShape.cols - inBoundarySize, outShape.cols),
108  lowerRight);
109  outArray.put(Slice(outShape.rows - inBoundarySize, outShape.rows), Slice(0, inBoundarySize), upperLeft);
110  outArray.put(Slice(outShape.rows - inBoundarySize, outShape.rows),
111  Slice(outShape.cols - inBoundarySize, outShape.cols),
112  upperRight);
113 
114  return outArray;
115  }
116  } // namespace boundary
117  } // namespace filter
118 } // namespace nc
#define STATIC_ASSERT_ARITHMETIC(dtype)
Definition: StaticAsserts.hpp:37
Holds 1D and 2D arrays, the main work horse of the NumCpp library.
Definition: NdArrayCore.hpp:72
NdArray< dtype > & put(int32 inIndex, value_type inValue)
Definition: NdArrayCore.hpp:3663
Shape shape() const noexcept
Definition: NdArrayCore.hpp:4276
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:44
NdArray< dtype > reflect2d(const NdArray< dtype > &inImage, uint32 inBoundarySize)
Definition: reflect2d.hpp:53
Definition: Coordinate.hpp:45
NdArray< dtype > flipud(const NdArray< dtype > &inArray)
Definition: flipud.hpp:46
std::uint32_t uint32
Definition: Types.hpp:40