
    #
3j	                     R    S SK rS SKrS SKJr  S SKJr  \" SSSS9S 5       rS	S jr	g)
    N)weights_to_laplacian)njitz/Tuple((f8[:], i4[:], i4[:]))(f8[:,:,:], f8, i4)T)cachenogilc                    U R                   S S u  p4X4-  nUSU-  S-   S-  -  n[        R                  " U[        R                  S9n[        R                  " U[        R                  S9n[        R                  " U5      n	Sn
[	        U5       H  n[	        U5       H  n[	        U* US-   5       H  n[	        U* US-   5       H  nX-   nX-   n[        S[        US-
  U5      5      n[        S[        US-
  U5      5      nXU-  -   nUUU-  -   nXU4   nU UU4   n[        R                  " S[        R                  R                  UU-
  5      S-  -  5      nUXz'   UX'   UX'   U
S-  n
M     M     M     M     XU4$ )N      )dtyper   i|)
shapenpemptyint32rangemaxminexplinalgnorm)imagesigmarhwnmi_indsj_indsvalueskyxdydxx2y2ijzizjwijs                         Z/home/wildlama/miniconda3/lib/python3.13/site-packages/pymatting/laplacian/rw_laplacian.py_rw_laplacianr,      ss   ;;r?DA	A	QUQY1AXXarxx(FXXarxx(FXXa[F	A1XqAQBA&AE*BBBQAE2/BQAE2/BE	AR!VA!tBr2vB&&		rBw(?1(D!DEC !FI !FI #FIFA) + '  2 6!!    c                     U R                   SS u  pEXE-  n[        XU5      u  pxn	[        R                  R	                  XxU	44Xf4S9n
[        XS9$ )a  
This function implements the alpha estimator for random walk alpha matting
as described in :cite:`grady2005random`.

Parameters
----------
image: numpy.ndarray
    Image with shape :math:`h\times w \times 3`
sigma: float
    Sigma used to calculate the weights (see Equation 4 in
    :cite:`grady2005random`), defaults to :math:`0.033`
radius: int
    Radius of local window size, defaults to :math:`1`, i.e. only adjacent
    pixels are considered. The size of the local window is given as
    :math:`(2 r + 1)^2`, where :math:`r` denotes the radius. A larger radius
    might lead to violated color line constraints, but also favors further
    propagation of information within the image.
regularization: float
    Regularization strength, defaults to :math:`10^{-8}`. Strong
    regularization improves convergence but results in smoother alpha matte.

Returns
-------
L: scipy.sparse.spmatrix
    Matting Laplacian
Nr   )r   )regularization)r   r,   scipysparse
csr_matrixr   )r   r   radiusr/   r   r   r   r   r   r   Ws              r+   rw_laplacianr5   /   s[    6 ;;r?DA	A*5@FF&)9 :1&IAAAr-   )gL7A`?r	   g:0yE>)
numpyr   scipy.sparser0   pymatting.util.utilr   numbar   r,   r5    r-   r+   <module>r;      s5      4 7t4P%" Q%"P"Br-   