OpenCV  3.4.20-dev
Open Source Computer Vision
Classes | Functions
Fourier descriptors


class  cv::ximgproc::ContourFitting
 Class for ContourFitting algorithms. ContourFitting match two contours \( z_a \) and \( z_b \) minimizing distance

\[ d(z_a,z_b)=\sum (a_n - s b_n e^{j(n \alpha +\phi )})^2 \]

where \( a_n \) and \( b_n \) are Fourier descriptors of \( z_a \) and \( z_b \) and s is a scaling factor and \( \phi \) is angle rotation and \( \alpha \) is starting point factor adjustement. More...



void cv::ximgproc::contourSampling (InputArray src, OutputArray out, int nbElt)
 Contour sampling . More...
Ptr< ContourFittingcv::ximgproc::createContourFitting (int ctr=1024, int fd=16)
 create ContourFitting algorithm object More...
void cv::ximgproc::fourierDescriptor (InputArray src, OutputArray dst, int nbElt=-1, int nbFD=-1)
 Fourier descriptors for planed closed curves. More...
void cv::ximgproc::transformFD (InputArray src, InputArray t, OutputArray dst, bool fdContour=true)
 transform a contour More...

Detailed Description

Function Documentation

◆ contourSampling()

void cv::ximgproc::contourSampling ( InputArray  src,
OutputArray  out,
int  nbElt 
cv.ximgproc.contourSampling(src, nbElt[, out]) -> out

#include <opencv2/ximgproc/fourier_descriptors.hpp>

Contour sampling .

srccontour type vector<Point> , vector<Point2f> or vector<Point2d>
outMat of type CV_64FC2 and nbElt rows
nbEltnumber of points in out contour

◆ createContourFitting()

Ptr<ContourFitting> cv::ximgproc::createContourFitting ( int  ctr = 1024,
int  fd = 16 
cv.ximgproc.createContourFitting([, ctr[, fd]]) -> retval

#include <opencv2/ximgproc/fourier_descriptors.hpp>

create ContourFitting algorithm object

ctrnumber of Fourier descriptors equal to number of contour points after resampling.
fdContour defining second shape (Target).

◆ fourierDescriptor()

void cv::ximgproc::fourierDescriptor ( InputArray  src,
OutputArray  dst,
int  nbElt = -1,
int  nbFD = -1 
cv.ximgproc.fourierDescriptor(src[, dst[, nbElt[, nbFD]]]) -> dst

#include <opencv2/ximgproc/fourier_descriptors.hpp>

Fourier descriptors for planed closed curves.

For more details about this implementation, please see [178]

srccontour type vector<Point> , vector<Point2f> or vector<Point2d>
dstMat of type CV_64FC2 and nbElt rows A VERIFIER
nbEltnumber of rows in dst or getOptimalDFTSize rows if nbElt=-1
nbFDnumber of FD return in dst dst = [FD(1...nbFD/2) FD(nbFD/2-nbElt+1...:nbElt)]

◆ transformFD()

void cv::ximgproc::transformFD ( InputArray  src,
InputArray  t,
OutputArray  dst,
bool  fdContour = true 
cv.ximgproc.transformFD(src, t[, dst[, fdContour]]) -> dst

#include <opencv2/ximgproc/fourier_descriptors.hpp>

transform a contour

srccontour or Fourier Descriptors if fd is true
ttransform Mat given by estimateTransformation
dstMat of type CV_64FC2 and nbElt rows
fdContourtrue src are Fourier Descriptors. fdContour false src is a contour