OpenLvVision_OpenCv.lvlib:GetPerspectiveTransform.vi

Calculates a perspective transform from four pairs of the corresponding points.

The function calculates a 3 × 3 perspective transformation matrix such that:

$ \begin{bmatrix} t_i x'_i \\ t_i y'_i \\ t_i \end{bmatrix} = \texttt{map\_matrix} \cdot \begin{bmatrix} x_i \\ y_i \\ 1 \end{bmatrix} $

where

$ \texttt{dst}(i) = (x'_i, y'_i), \quad \texttt{src}(i) = (x_i, y_i), \quad i = 0,1,2,3 $

For detailed information, please refer to the OpenCV documentation

OpenLvVision_OpenCv.lvlib:GetPerspectiveTransform.vi

cerrcodeclst

error in

error in can accept error information wired from VIs previously called. Use this information to decide if any functionality should be bypassed in the event of errors from other VIs.

Right-click the error in control on the front panel and select Explain Error or Explain Warning from the shortcut menu for more information about the error.

    cbool

    		status

    status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.

    Right-click the error in control on the front panel and select Explain Error or Explain Warning from the shortcut menu for more information about the error.

    ci32

    		code

    cstr

    		source

    source describes the origin of the error or warning.

    Right-click the error in control on the front panel and select Explain Error or Explain Warning from the shortcut menu for more information about the error.

c1dnclst

Src

Coordinates of quadrangle vertices in the source image.

    cnclst

    		Point

      csgl

      		X

      csgl

      		Y

c1dnclst

Dst

Coordinates of the corresponding quadrangle vertices in the destination image.

    cnclst

    		Point

      csgl

      		X

      csgl

      		Y

ci32

DecompTypes

method passed to cv::solve

DECOMP_LU: Gaussian elimination with the optimal pivot element chosen.

DECOMP_SVD : singular value decomposition (SVD) method; the system can be over-defined and/or the matrix

DECOMP_EIG: eigenvalue decomposition; the matrix src1 must be symmetrical

DECOMP_CHOLESKY: Cholesky factorization. he matrix src1 must be symmetrical and positively defined.

DECOMP_QR: QR factorization; the system can be over-defined and/or the matrix src1 can be singular

DECOMP_NORMAL:while all the previous flags are mutually exclusive, this flag can be used together with any of the previous; it means that the normal equations

ierrcodeclst

error out

error in can accept error information wired from VIs previously called. Use this information to decide if any functionality should be bypassed in the event of errors from other VIs.

Right-click the error in control on the front panel and select Explain Error or Explain Warning from the shortcut menu for more information about the error.

    ibool

    		status

    status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.

    Right-click the error in control on the front panel and select Explain Error or Explain Warning from the shortcut menu for more information about the error.

    ii32

    		code

    istr

    		source

    source describes the origin of the error or warning.

    Right-click the error in control on the front panel and select Explain Error or Explain Warning from the shortcut menu for more information about the error.

i2ddbl

Result

    idbl

    		Numeric