Specifications

Geometric Transforms
11-27
11
quad Output array: coordinates of the quadrangle to
which the
image ’s ROI would be mapped by
iplWarpPerspective().
Discussion
The function iplGetPerspectiveQuad() computes coordinates of the
quadrangle to which the image ’s ROI would be mapped by
iplWarpPerspective() with the transform coefficients coeffs .
GetPerspectiveTransform
Computes the coefficients of
iplWarpPerspective, given the
ROI-quadrangle pair.
void iplGetPerspectiveTransform(IplImage* image , double
coeffs [3][3], const double quad [4][2]);
image The image to be passed to
iplWarpPerspective().
coeffs Output array: perspective transform coefficients.
quad Coordinates of the 4 points to which the image ’s
ROI vertices would be mapped by
iplWarpPerspective().
Discussion
The function iplGetPerspectiveTransform() computes the
iplWarpPerspective() transform coefficients, given the vertices of the
quadrangle to which the
image ’s ROI would be mapped by
iplWarpBilinear() with these coefficients.