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Fonction fourier_gaussian - module scipy.ndimage

Signature de la fonction fourier_gaussian

def fourier_gaussian(input, sigma, n=-1, axis=-1, output=None) 

Description

fourier_gaussian.__doc__

    Multidimensional Gaussian fourier filter.

    The array is multiplied with the fourier transform of a Gaussian
    kernel.

    Parameters
    ----------
    input : array_like
        The input array.
    sigma : float or sequence
        The sigma of the Gaussian kernel. If a float, `sigma` is the same for
        all axes. If a sequence, `sigma` has to contain one value for each
        axis.
    n : int, optional
        If `n` is negative (default), then the input is assumed to be the
        result of a complex fft.
        If `n` is larger than or equal to zero, the input is assumed to be the
        result of a real fft, and `n` gives the length of the array before
        transformation along the real transform direction.
    axis : int, optional
        The axis of the real transform.
    output : ndarray, optional
        If given, the result of filtering the input is placed in this array.
        None is returned in this case.

    Returns
    -------
    fourier_gaussian : ndarray
        The filtered input.

    Examples
    --------
    >>> from scipy import ndimage, misc
    >>> import numpy.fft
    >>> import matplotlib.pyplot as plt
    >>> fig, (ax1, ax2) = plt.subplots(1, 2)
    >>> plt.gray()  # show the filtered result in grayscale
    >>> ascent = misc.ascent()
    >>> input_ = numpy.fft.fft2(ascent)
    >>> result = ndimage.fourier_gaussian(input_, sigma=4)
    >>> result = numpy.fft.ifft2(result)
    >>> ax1.imshow(ascent)
    >>> ax2.imshow(result.real)  # the imaginary part is an artifact
    >>> plt.show()