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Documentation> MATLAB API> IMOP - vl_imintegral

J = VL_IMINTEGRAL(I) calculates the integral image J of the image I. I must a matrix with DOUBLE, SINGLE, UINT32, or INT32 storage class. J is given by

     J(i,j) = sum(I(1:i,1:j)).

J has the same size as I and the same storage class.

Example

  The following identity holds:

        VL_IMINTEGRAL(ONES(3)) = [ 1 2 3 ;
                                   2 4 6 ;
                                   3 6 9 ]

See also: VL_HELP().