Background Interpolators

Background.BackgroundInterpolator

This abstract type embodies the different ways of converting a low-resolution mesh into a high-resolution image, especially for dispatch with estimate_background

To implement a new interpolation scheme, you must define the struct and define a method like (::MyInterpolator)(mesh)

See Also

• Interpolators

ZoomInterpolator(factors)

Use a cubic-spline interpolation scheme to increase resolution of a mesh.

factors represents the level of "zoom", so an input mesh of size (10, 10) with factors (2, 2) will have an output size of (20, 20). If only an integer is provided, it will be used as the factor for every axis.

Examples

julia> ZoomInterpolator(2)([1 0; 0 1])
4×4 Matrix{Float64}:
  1.0          0.75   0.25   -2.77556e-17
  0.75         0.625  0.375   0.25
  0.25         0.375  0.625   0.75
 -5.55112e-17  0.25   0.75    1.0

julia> ZoomInterpolator(3, 1)([1 0; 0 1])
6×2 Matrix{Float64}:
  1.0          -2.77556e-17
  1.0          -2.77556e-17
  0.666667      0.333333
  0.333333      0.666667
 -5.55112e-17   1.0
 -5.55112e-17   1.0

IDWInterpolator(factors; leafsize=10, k=8, power=1, reg=0, conf_dist=1e-12)

Use Shepard Inverse Distance Weighing interpolation scheme to increase resolution of a mesh.

factors represents the level of "zoom", so an input mesh of size (10, 10) with factors (2, 2) will have an output size of (20, 20). If only an integer is provided, it will be used as the factor for every axis.

The interpolator can be called with some additional parameters:

• leaf_size determines at what number of points to stop splitting the tree further,
• k which is the number of nearest neighbors to be considered,
• power is the exponent for distance in the weighing factor,
• reg is the offset for the weighing factor in denominator,
• conf_dist is the distance below which two points would be considered as the same point.

Examples

julia> IDWInterpolator(2, k=2)([1 0; 0 1])
4×4 Matrix{Float64}:
 1.0   0.75      0.25      0.0
 0.75  0.690983  0.309017  0.25
 0.25  0.309017  0.690983  0.75
 0.0   0.25      0.75      1.0

julia> IDWInterpolator(3, 1; k=2, power=4)([1 0; 0 1])
6×2 Matrix{Float64}:
 1.0        0.0
 1.0        0.0
 0.941176   0.0588235
 0.0588235  0.941176
 0.0        1.0
 0.0        1.0