o :ήc´ã@s"ddlmZddlZddd„ZdS)é)Ú trimap_splitNçY@FcCsl|jdd…\}}t|ƒ\}}}} ||} ||} tj | ¡} || } |  ¡} |  ¡|r2| | | fS| | fS)aòThis function constructs a linear system from a matting Laplacian by constraining the foreground and background pixels with a diagonal matrix `C` to values in the right-hand-side vector `b`. The constraints are weighted by a factor :math:`\lambda`. The linear system is given as .. math:: A = L + \lambda C, where :math:`C=\mathop{Diag}(c)` having :math:`c_i = 1` if pixel i is known and :math:`c_i = 0` otherwise. The right-hand-side :math:`b` is a vector with entries :math:`b_i = 1` is pixel is is a foreground pixel and :math:`b_i = 0` otherwise. Parameters ---------- L: scipy.sparse.spmatrix Laplacian matrix, e.g. calculated with :code:`lbdm_laplacian` function trimap: numpy.ndarray Trimap with shape :math:`h\times w` lambda_value: float Constraint penalty, defaults to 100 return_c: bool Whether to return the constraint matrix `C`, defaults to False Returns ------- A: scipy.sparse.spmatrix Matrix describing the system of linear equations b: numpy.ndarray Vector describing the right-hand side of the system C: numpy.ndarray Vector describing the diagonal entries of the matrix `C`, only returned if `return_c` is set to True Né)ÚshaperÚscipyÚsparseÚdiagsÚtocsrÚsum_duplicates)ÚLÚtrimapÚ lambda_valueÚreturn_cÚhÚwÚis_fgÚis_bgÚis_knownÚ is_unknownÚcÚbÚCÚA©rúD/tmp/pip-target-vg8gfxp4/lib/python/pymatting/laplacian/laplacian.pyÚmake_linear_systems  r)rF)Úpymatting.util.utilrÚ scipy.sparserrrrrrÚs