astro.denoising.wavelet#

WAVELET.

This module defines functions for wavelet decomposition.

decompose(data, n_scales=4)[source]#

Decompose.

Obtain the wavelet decomposition of the input data using an isotropic undecimated wavelet transform.

Parameters

data (numpy.ndarray) – Input 2D-array
n_scales (int, optional) – Number of wavelet scales, default is 4

Returns

Wavelet decomposition 3D-array

Return type

numpy.ndarray

Raises

TypeError – For invalid input data type
TypeError – For invalid input n_scales type

Examples

>>> import numpy as np
>>> from astro.denoising.wavelet import decompose
>>> data = np.arange(9).reshape((3, 3)) * 0.1
>>> decompose(data)
array([[[-1.50000006e-01, -1.12500034e-01, -7.50000030e-02],
        [-3.75000238e-02, -2.98023224e-08,  3.74999642e-02],
        [ 7.49999881e-02,  1.12499952e-01,  1.49999976e-01]],

[[-1.56250030e-01, -1.17187500e-01, -7.81250298e-02],
[-3.90625000e-02, 0.00000000e+00, 3.90625000e-02], [ 7.81250000e-02, 1.17187500e-01, 1.56250000e-01]],

[[-5.85937500e-02, -4.39453125e-02, -2.92968750e-02],
[-1.46484375e-02, 0.00000000e+00, 1.46484375e-02], [ 2.92968750e-02, 4.39453125e-02, 5.85937500e-02]],

[[ 3.64843786e-01, 3.73632848e-01, 3.82421911e-01],
[ 3.91210973e-01, 4.00000036e-01, 4.08789098e-01], [ 4.17578161e-01, 4.26367223e-01, 4.35156286e-01]]])

recombine(data)[source]#

Recombine.

Recombine a wavelet decomposition.

Parameters: data (numpy.ndarray) – Input 3D-array
Returns: Recombined 2D-array
Return type: numpy.ndarray
Raises: TypeError – For invalid input data type

Examples

>>> import numpy as np
>>> from pysap.astro.denoising.wavelet import recombine
>>> np.random.seed(0)
>>> data = np.random.ranf((4, 3, 3))
>>> recombine(data)
array([[2.65508069, 2.89877487, 2.52493858],
       [2.17664192, 2.58496449, 1.95360968],
       [1.21142489, 1.57070222, 2.55727139]])