hessian-matrix-eigvals

hessian_matrix_eigvals

skimage.feature.hessian_matrix_eigvals(Hxx, Hxy, Hyy) [source]

Compute Eigen values of Hessian matrix.

Parameters:	Hxx : ndarray Element of the Hessian matrix for each pixel in the input image. Hxy : ndarray Element of the Hessian matrix for each pixel in the input image. Hyy : ndarray Element of the Hessian matrix for each pixel in the input image.
Returns:	l1 : ndarray Larger eigen value for each input matrix. l2 : ndarray Smaller eigen value for each input matrix.

Examples

>>> from skimage.feature import hessian_matrix, hessian_matrix_eigvals
>>> square = np.zeros((5, 5))
>>> square[2, 2] = -1 / 1591.54943092
>>> Hxx, Hxy, Hyy = hessian_matrix(square, sigma=0.1)
>>> hessian_matrix_eigvals(Hxx, Hxy, Hyy)[0]
array([[ 0.,  0.,  0.,  0.,  0.],
       [ 0.,  0.,  0.,  0.,  0.],
       [ 0.,  0.,  1.,  0.,  0.],
       [ 0.,  0.,  0.,  0.,  0.],
       [ 0.,  0.,  0.,  0.,  0.]])