opencv/modules/calib3d/src/fundam.cpp
Tiago De Gaspari ac9182f20d Add maxIters parameter to LMeDS method in findFundamentalMat
This commit passes the parameter maxIters that represent
the maximum number of iterations, that can be passed to findFundamentalMat
to the method LMeDS.

This parameter were added to the function findFundamentalMat and
were passed just for the RANSAC method, but should be passed to
both methods to be consistent.
2021-04-03 21:56:05 -03:00

1197 lines
39 KiB
C++

/*M///////////////////////////////////////////////////////////////////////////////////////
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#include "precomp.hpp"
#include "rho.h"
#include <iostream>
namespace cv
{
/**
* This class estimates a homography \f$H\in \mathbb{R}^{3\times 3}\f$
* between \f$\mathbf{x} \in \mathbb{R}^3\f$ and
* \f$\mathbf{X} \in \mathbb{R}^3\f$ using DLT (direct linear transform)
* with algebraic distance.
*
* \f[
* \lambda \mathbf{x} = H \mathbf{X}
* \f]
* where \f$\lambda \in \mathbb{R} \f$.
*
*/
class HomographyEstimatorCallback CV_FINAL : public PointSetRegistrator::Callback
{
public:
bool checkSubset( InputArray _ms1, InputArray _ms2, int count ) const CV_OVERRIDE
{
Mat ms1 = _ms1.getMat(), ms2 = _ms2.getMat();
if( haveCollinearPoints(ms1, count) || haveCollinearPoints(ms2, count) )
return false;
// We check whether the minimal set of points for the homography estimation
// are geometrically consistent. We check if every 3 correspondences sets
// fulfills the constraint.
//
// The usefulness of this constraint is explained in the paper:
//
// "Speeding-up homography estimation in mobile devices"
// Journal of Real-Time Image Processing. 2013. DOI: 10.1007/s11554-012-0314-1
// Pablo Marquez-Neila, Javier Lopez-Alberca, Jose M. Buenaposada, Luis Baumela
if( count == 4 )
{
static const int tt[][3] = {{0, 1, 2}, {1, 2, 3}, {0, 2, 3}, {0, 1, 3}};
const Point2f* src = ms1.ptr<Point2f>();
const Point2f* dst = ms2.ptr<Point2f>();
int negative = 0;
for( int i = 0; i < 4; i++ )
{
const int* t = tt[i];
Matx33d A(src[t[0]].x, src[t[0]].y, 1., src[t[1]].x, src[t[1]].y, 1., src[t[2]].x, src[t[2]].y, 1.);
Matx33d B(dst[t[0]].x, dst[t[0]].y, 1., dst[t[1]].x, dst[t[1]].y, 1., dst[t[2]].x, dst[t[2]].y, 1.);
negative += determinant(A)*determinant(B) < 0;
}
if( negative != 0 && negative != 4 )
return false;
}
return true;
}
/**
* Normalization method:
* - $x$ and $y$ coordinates are normalized independently
* - first the coordinates are shifted so that the average coordinate is \f$(0,0)\f$
* - then the coordinates are scaled so that the average L1 norm is 1, i.e,
* the average L1 norm of the \f$x\f$ coordinates is 1 and the average
* L1 norm of the \f$y\f$ coordinates is also 1.
*
* @param _m1 source points containing (X,Y), depth is CV_32F with 1 column 2 channels or
* 2 columns 1 channel
* @param _m2 destination points containing (x,y), depth is CV_32F with 1 column 2 channels or
* 2 columns 1 channel
* @param _model, CV_64FC1, 3x3, normalized, i.e., the last element is 1
*/
int runKernel( InputArray _m1, InputArray _m2, OutputArray _model ) const CV_OVERRIDE
{
Mat m1 = _m1.getMat(), m2 = _m2.getMat();
int i, count = m1.checkVector(2);
const Point2f* M = m1.ptr<Point2f>();
const Point2f* m = m2.ptr<Point2f>();
double LtL[9][9], W[9][1], V[9][9];
Mat _LtL( 9, 9, CV_64F, &LtL[0][0] );
Mat matW( 9, 1, CV_64F, W );
Mat matV( 9, 9, CV_64F, V );
Mat _H0( 3, 3, CV_64F, V[8] );
Mat _Htemp( 3, 3, CV_64F, V[7] );
Point2d cM(0,0), cm(0,0), sM(0,0), sm(0,0);
for( i = 0; i < count; i++ )
{
cm.x += m[i].x; cm.y += m[i].y;
cM.x += M[i].x; cM.y += M[i].y;
}
cm.x /= count;
cm.y /= count;
cM.x /= count;
cM.y /= count;
for( i = 0; i < count; i++ )
{
sm.x += fabs(m[i].x - cm.x);
sm.y += fabs(m[i].y - cm.y);
sM.x += fabs(M[i].x - cM.x);
sM.y += fabs(M[i].y - cM.y);
}
if( fabs(sm.x) < DBL_EPSILON || fabs(sm.y) < DBL_EPSILON ||
fabs(sM.x) < DBL_EPSILON || fabs(sM.y) < DBL_EPSILON )
return 0;
sm.x = count/sm.x; sm.y = count/sm.y;
sM.x = count/sM.x; sM.y = count/sM.y;
double invHnorm[9] = { 1./sm.x, 0, cm.x, 0, 1./sm.y, cm.y, 0, 0, 1 };
double Hnorm2[9] = { sM.x, 0, -cM.x*sM.x, 0, sM.y, -cM.y*sM.y, 0, 0, 1 };
Mat _invHnorm( 3, 3, CV_64FC1, invHnorm );
Mat _Hnorm2( 3, 3, CV_64FC1, Hnorm2 );
_LtL.setTo(Scalar::all(0));
for( i = 0; i < count; i++ )
{
double x = (m[i].x - cm.x)*sm.x, y = (m[i].y - cm.y)*sm.y;
double X = (M[i].x - cM.x)*sM.x, Y = (M[i].y - cM.y)*sM.y;
double Lx[] = { X, Y, 1, 0, 0, 0, -x*X, -x*Y, -x };
double Ly[] = { 0, 0, 0, X, Y, 1, -y*X, -y*Y, -y };
int j, k;
for( j = 0; j < 9; j++ )
for( k = j; k < 9; k++ )
LtL[j][k] += Lx[j]*Lx[k] + Ly[j]*Ly[k];
}
completeSymm( _LtL );
eigen( _LtL, matW, matV );
_Htemp = _invHnorm*_H0;
_H0 = _Htemp*_Hnorm2;
_H0.convertTo(_model, _H0.type(), 1./_H0.at<double>(2,2) );
return 1;
}
/**
* Compute the reprojection error.
* m2 = H*m1
* @param _m1 depth CV_32F, 1-channel with 2 columns or 2-channel with 1 column
* @param _m2 depth CV_32F, 1-channel with 2 columns or 2-channel with 1 column
* @param _model CV_64FC1, 3x3
* @param _err, output, CV_32FC1, square of the L2 norm
*/
void computeError( InputArray _m1, InputArray _m2, InputArray _model, OutputArray _err ) const CV_OVERRIDE
{
Mat m1 = _m1.getMat(), m2 = _m2.getMat(), model = _model.getMat();
int i, count = m1.checkVector(2);
const Point2f* M = m1.ptr<Point2f>();
const Point2f* m = m2.ptr<Point2f>();
const double* H = model.ptr<double>();
float Hf[] = { (float)H[0], (float)H[1], (float)H[2], (float)H[3], (float)H[4], (float)H[5], (float)H[6], (float)H[7] };
_err.create(count, 1, CV_32F);
float* err = _err.getMat().ptr<float>();
for( i = 0; i < count; i++ )
{
float ww = 1.f/(Hf[6]*M[i].x + Hf[7]*M[i].y + 1.f);
float dx = (Hf[0]*M[i].x + Hf[1]*M[i].y + Hf[2])*ww - m[i].x;
float dy = (Hf[3]*M[i].x + Hf[4]*M[i].y + Hf[5])*ww - m[i].y;
err[i] = dx*dx + dy*dy;
}
}
};
class HomographyRefineCallback CV_FINAL : public LMSolver::Callback
{
public:
HomographyRefineCallback(InputArray _src, InputArray _dst)
{
src = _src.getMat();
dst = _dst.getMat();
}
bool compute(InputArray _param, OutputArray _err, OutputArray _Jac) const CV_OVERRIDE
{
int i, count = src.checkVector(2);
Mat param = _param.getMat();
_err.create(count*2, 1, CV_64F);
Mat err = _err.getMat(), J;
if( _Jac.needed())
{
_Jac.create(count*2, param.rows, CV_64F);
J = _Jac.getMat();
CV_Assert( J.isContinuous() && J.cols == 8 );
}
const Point2f* M = src.ptr<Point2f>();
const Point2f* m = dst.ptr<Point2f>();
const double* h = param.ptr<double>();
double* errptr = err.ptr<double>();
double* Jptr = J.data ? J.ptr<double>() : 0;
for( i = 0; i < count; i++ )
{
double Mx = M[i].x, My = M[i].y;
double ww = h[6]*Mx + h[7]*My + 1.;
ww = fabs(ww) > DBL_EPSILON ? 1./ww : 0;
double xi = (h[0]*Mx + h[1]*My + h[2])*ww;
double yi = (h[3]*Mx + h[4]*My + h[5])*ww;
errptr[i*2] = xi - m[i].x;
errptr[i*2+1] = yi - m[i].y;
if( Jptr )
{
Jptr[0] = Mx*ww; Jptr[1] = My*ww; Jptr[2] = ww;
Jptr[3] = Jptr[4] = Jptr[5] = 0.;
Jptr[6] = -Mx*ww*xi; Jptr[7] = -My*ww*xi;
Jptr[8] = Jptr[9] = Jptr[10] = 0.;
Jptr[11] = Mx*ww; Jptr[12] = My*ww; Jptr[13] = ww;
Jptr[14] = -Mx*ww*yi; Jptr[15] = -My*ww*yi;
Jptr += 16;
}
}
return true;
}
Mat src, dst;
};
} // end namesapce cv
namespace cv{
static bool createAndRunRHORegistrator(double confidence,
int maxIters,
double ransacReprojThreshold,
int npoints,
InputArray _src,
InputArray _dst,
OutputArray _H,
OutputArray _tempMask){
Mat src = _src.getMat();
Mat dst = _dst.getMat();
Mat tempMask;
bool result;
double beta = 0.35;/* 0.35 is a value that often works. */
/* Create temporary output matrix (RHO outputs a single-precision H only). */
Mat tmpH = Mat(3, 3, CV_32FC1);
/* Create output mask. */
tempMask = Mat(npoints, 1, CV_8U);
/**
* Make use of the RHO estimator API.
*
* This is where the math happens. A homography estimation context is
* initialized, used, then finalized.
*/
Ptr<RHO_HEST> p = rhoInit();
/**
* Optional. Ideally, the context would survive across calls to
* findHomography(), but no clean way appears to exit to do so. The price
* to pay is marginally more computational work than strictly needed.
*/
rhoEnsureCapacity(p, npoints, beta);
/**
* The critical call. All parameters are heavily documented in rho.h.
*
* Currently, NR (Non-Randomness criterion) and Final Refinement (with
* internal, optimized Levenberg-Marquardt method) are enabled. However,
* while refinement seems to correctly smooth jitter most of the time, when
* refinement fails it tends to make the estimate visually very much worse.
* It may be necessary to remove the refinement flags in a future commit if
* this behaviour is too problematic.
*/
result = !!rhoHest(p,
(const float*)src.data,
(const float*)dst.data,
(char*) tempMask.data,
(unsigned) npoints,
(float) ransacReprojThreshold,
(unsigned) maxIters,
(unsigned) maxIters,
confidence,
4U,
beta,
RHO_FLAG_ENABLE_NR | RHO_FLAG_ENABLE_FINAL_REFINEMENT,
NULL,
(float*)tmpH.data);
/* Convert float homography to double precision. */
tmpH.convertTo(_H, CV_64FC1);
/* Maps non-zero mask elements to 1, for the sake of the test case. */
for(int k=0;k<npoints;k++){
tempMask.data[k] = !!tempMask.data[k];
}
tempMask.copyTo(_tempMask);
return result;
}
}
cv::Mat cv::findHomography( InputArray _points1, InputArray _points2,
int method, double ransacReprojThreshold, OutputArray _mask,
const int maxIters, const double confidence)
{
CV_INSTRUMENT_REGION();
const double defaultRANSACReprojThreshold = 3;
bool result = false;
Mat points1 = _points1.getMat(), points2 = _points2.getMat();
Mat src, dst, H, tempMask;
int npoints = -1;
for( int i = 1; i <= 2; i++ )
{
Mat& p = i == 1 ? points1 : points2;
Mat& m = i == 1 ? src : dst;
npoints = p.checkVector(2, -1, false);
if( npoints < 0 )
{
npoints = p.checkVector(3, -1, false);
if( npoints < 0 )
CV_Error(Error::StsBadArg, "The input arrays should be 2D or 3D point sets");
if( npoints == 0 )
return Mat();
convertPointsFromHomogeneous(p, p);
}
// Need at least 4 point correspondences to calculate Homography
if( npoints < 4 )
CV_Error(Error::StsVecLengthErr , "The input arrays should have at least 4 corresponding point sets to calculate Homography");
p.reshape(2, npoints).convertTo(m, CV_32F);
}
CV_Assert( src.checkVector(2) == dst.checkVector(2) );
if( ransacReprojThreshold <= 0 )
ransacReprojThreshold = defaultRANSACReprojThreshold;
Ptr<PointSetRegistrator::Callback> cb = makePtr<HomographyEstimatorCallback>();
if( method == 0 || npoints == 4 )
{
tempMask = Mat::ones(npoints, 1, CV_8U);
result = cb->runKernel(src, dst, H) > 0;
}
else if( method == RANSAC )
result = createRANSACPointSetRegistrator(cb, 4, ransacReprojThreshold, confidence, maxIters)->run(src, dst, H, tempMask);
else if( method == LMEDS )
result = createLMeDSPointSetRegistrator(cb, 4, confidence, maxIters)->run(src, dst, H, tempMask);
else if( method == RHO )
result = createAndRunRHORegistrator(confidence, maxIters, ransacReprojThreshold, npoints, src, dst, H, tempMask);
else
CV_Error(Error::StsBadArg, "Unknown estimation method");
if( result && npoints > 4 && method != RHO)
{
compressElems( src.ptr<Point2f>(), tempMask.ptr<uchar>(), 1, npoints );
npoints = compressElems( dst.ptr<Point2f>(), tempMask.ptr<uchar>(), 1, npoints );
if( npoints > 0 )
{
Mat src1 = src.rowRange(0, npoints);
Mat dst1 = dst.rowRange(0, npoints);
src = src1;
dst = dst1;
if( method == RANSAC || method == LMEDS )
cb->runKernel( src, dst, H );
Mat H8(8, 1, CV_64F, H.ptr<double>());
createLMSolver(makePtr<HomographyRefineCallback>(src, dst), 10)->run(H8);
}
}
if( result )
{
if( _mask.needed() )
tempMask.copyTo(_mask);
}
else
{
H.release();
if(_mask.needed() ) {
tempMask = Mat::zeros(npoints >= 0 ? npoints : 0, 1, CV_8U);
tempMask.copyTo(_mask);
}
}
return H;
}
cv::Mat cv::findHomography( InputArray _points1, InputArray _points2,
OutputArray _mask, int method, double ransacReprojThreshold )
{
return cv::findHomography(_points1, _points2, method, ransacReprojThreshold, _mask);
}
/* Estimation of Fundamental Matrix from point correspondences.
The original code has been written by Valery Mosyagin */
/* The algorithms (except for RANSAC) and the notation have been taken from
Zhengyou Zhang's research report
"Determining the Epipolar Geometry and its Uncertainty: A Review"
that can be found at http://www-sop.inria.fr/robotvis/personnel/zzhang/zzhang-eng.html */
/************************************** 7-point algorithm *******************************/
namespace cv
{
/**
* Compute the fundamental matrix using the 7-point algorithm.
*
* \f[
* (\mathrm{m2}_i,1)^T \mathrm{fmatrix} (\mathrm{m1}_i,1) = 0
* \f]
*
* @param _m1 Contain points in the reference view. Depth CV_32F with 2-channel
* 1 column or 1-channel 2 columns. It has 7 rows.
* @param _m2 Contain points in the other view. Depth CV_32F with 2-channel
* 1 column or 1-channel 2 columns. It has 7 rows.
* @param _fmatrix Output fundamental matrix (or matrices) of type CV_64FC1.
* The user is responsible for allocating the memory before calling
* this function.
* @return Number of fundamental matrices. Valid values are 1, 2 or 3.
* - 1, row 0 to row 2 in _fmatrix is a valid fundamental matrix
* - 2, row 3 to row 5 in _fmatrix is a valid fundamental matrix
* - 3, row 6 to row 8 in _fmatrix is a valid fundamental matrix
*
* Note that the computed fundamental matrix is normalized, i.e.,
* the last element \f$F_{33}\f$ is 1.
*/
static int run7Point( const Mat& _m1, const Mat& _m2, Mat& _fmatrix )
{
double a[7*9], w[7], u[9*9], v[9*9], c[4], r[3] = {0};
double* f1, *f2;
double t0, t1, t2;
Mat A( 7, 9, CV_64F, a );
Mat U( 7, 9, CV_64F, u );
Mat Vt( 9, 9, CV_64F, v );
Mat W( 7, 1, CV_64F, w );
Mat coeffs( 1, 4, CV_64F, c );
Mat roots( 1, 3, CV_64F, r );
const Point2f* m1 = _m1.ptr<Point2f>();
const Point2f* m2 = _m2.ptr<Point2f>();
double* fmatrix = _fmatrix.ptr<double>();
int i, k, n;
Point2d m1c(0, 0), m2c(0, 0);
double t, scale1 = 0, scale2 = 0;
const int count = 7;
// compute centers and average distances for each of the two point sets
for( i = 0; i < count; i++ )
{
m1c += Point2d(m1[i]);
m2c += Point2d(m2[i]);
}
// calculate the normalizing transformations for each of the point sets:
// after the transformation each set will have the mass center at the coordinate origin
// and the average distance from the origin will be ~sqrt(2).
t = 1./count;
m1c *= t;
m2c *= t;
for( i = 0; i < count; i++ )
{
scale1 += norm(Point2d(m1[i].x - m1c.x, m1[i].y - m1c.y));
scale2 += norm(Point2d(m2[i].x - m2c.x, m2[i].y - m2c.y));
}
scale1 *= t;
scale2 *= t;
if( scale1 < FLT_EPSILON || scale2 < FLT_EPSILON )
return 0;
scale1 = std::sqrt(2.)/scale1;
scale2 = std::sqrt(2.)/scale2;
// form a linear system: i-th row of A(=a) represents
// the equation: (m2[i], 1)'*F*(m1[i], 1) = 0
for( i = 0; i < 7; i++ )
{
double x0 = (m1[i].x - m1c.x)*scale1;
double y0 = (m1[i].y - m1c.y)*scale1;
double x1 = (m2[i].x - m2c.x)*scale2;
double y1 = (m2[i].y - m2c.y)*scale2;
a[i*9+0] = x1*x0;
a[i*9+1] = x1*y0;
a[i*9+2] = x1;
a[i*9+3] = y1*x0;
a[i*9+4] = y1*y0;
a[i*9+5] = y1;
a[i*9+6] = x0;
a[i*9+7] = y0;
a[i*9+8] = 1;
}
// A*(f11 f12 ... f33)' = 0 is singular (7 equations for 9 variables), so
// the solution is linear subspace of dimensionality 2.
// => use the last two singular vectors as a basis of the space
// (according to SVD properties)
SVDecomp( A, W, U, Vt, SVD::MODIFY_A + SVD::FULL_UV );
f1 = v + 7*9;
f2 = v + 8*9;
// f1, f2 is a basis => lambda*f1 + mu*f2 is an arbitrary fundamental matrix,
// as it is determined up to a scale, normalize lambda & mu (lambda + mu = 1),
// so f ~ lambda*f1 + (1 - lambda)*f2.
// use the additional constraint det(f) = det(lambda*f1 + (1-lambda)*f2) to find lambda.
// it will be a cubic equation.
// find c - polynomial coefficients.
for( i = 0; i < 9; i++ )
f1[i] -= f2[i];
t0 = f2[4]*f2[8] - f2[5]*f2[7];
t1 = f2[3]*f2[8] - f2[5]*f2[6];
t2 = f2[3]*f2[7] - f2[4]*f2[6];
c[3] = f2[0]*t0 - f2[1]*t1 + f2[2]*t2;
c[2] = f1[0]*t0 - f1[1]*t1 + f1[2]*t2 -
f1[3]*(f2[1]*f2[8] - f2[2]*f2[7]) +
f1[4]*(f2[0]*f2[8] - f2[2]*f2[6]) -
f1[5]*(f2[0]*f2[7] - f2[1]*f2[6]) +
f1[6]*(f2[1]*f2[5] - f2[2]*f2[4]) -
f1[7]*(f2[0]*f2[5] - f2[2]*f2[3]) +
f1[8]*(f2[0]*f2[4] - f2[1]*f2[3]);
t0 = f1[4]*f1[8] - f1[5]*f1[7];
t1 = f1[3]*f1[8] - f1[5]*f1[6];
t2 = f1[3]*f1[7] - f1[4]*f1[6];
c[1] = f2[0]*t0 - f2[1]*t1 + f2[2]*t2 -
f2[3]*(f1[1]*f1[8] - f1[2]*f1[7]) +
f2[4]*(f1[0]*f1[8] - f1[2]*f1[6]) -
f2[5]*(f1[0]*f1[7] - f1[1]*f1[6]) +
f2[6]*(f1[1]*f1[5] - f1[2]*f1[4]) -
f2[7]*(f1[0]*f1[5] - f1[2]*f1[3]) +
f2[8]*(f1[0]*f1[4] - f1[1]*f1[3]);
c[0] = f1[0]*t0 - f1[1]*t1 + f1[2]*t2;
// solve the cubic equation; there can be 1 to 3 roots ...
n = solveCubic( coeffs, roots );
if( n < 1 || n > 3 )
return n;
// transformation matrices
Matx33d T1( scale1, 0, -scale1*m1c.x, 0, scale1, -scale1*m1c.y, 0, 0, 1 );
Matx33d T2( scale2, 0, -scale2*m2c.x, 0, scale2, -scale2*m2c.y, 0, 0, 1 );
for( k = 0; k < n; k++, fmatrix += 9 )
{
// for each root form the fundamental matrix
double lambda = r[k], mu = 1.;
double s = f1[8]*r[k] + f2[8];
// normalize each matrix, so that F(3,3) (~fmatrix[8]) == 1
if( fabs(s) > DBL_EPSILON )
{
mu = 1./s;
lambda *= mu;
fmatrix[8] = 1.;
}
else
fmatrix[8] = 0.;
for( i = 0; i < 8; i++ )
fmatrix[i] = f1[i]*lambda + f2[i]*mu;
// de-normalize
Mat F(3, 3, CV_64F, fmatrix);
F = T2.t() * F * T1;
// make F(3,3) = 1
if(fabs(F.at<double>(8)) > FLT_EPSILON )
F *= 1. / F.at<double>(8);
}
return n;
}
/**
* Compute the fundamental matrix using the 8-point algorithm.
*
* \f[
* (\mathrm{m2}_i,1)^T \mathrm{fmatrix} (\mathrm{m1}_i,1) = 0
* \f]
*
* @param _m1 Contain points in the reference view. Depth CV_32F with 2-channel
* 1 column or 1-channel 2 columns. It has 8 rows.
* @param _m2 Contain points in the other view. Depth CV_32F with 2-channel
* 1 column or 1-channel 2 columns. It has 8 rows.
* @param _fmatrix Output fundamental matrix (or matrices) of type CV_64FC1.
* The user is responsible for allocating the memory before calling
* this function.
* @return 1 on success, 0 on failure.
*
* Note that the computed fundamental matrix is normalized, i.e.,
* the last element \f$F_{33}\f$ is 1.
*/
static int run8Point( const Mat& _m1, const Mat& _m2, Mat& _fmatrix )
{
Point2d m1c(0,0), m2c(0,0);
double t, scale1 = 0, scale2 = 0;
const Point2f* m1 = _m1.ptr<Point2f>();
const Point2f* m2 = _m2.ptr<Point2f>();
CV_Assert( (_m1.cols == 1 || _m1.rows == 1) && _m1.size() == _m2.size());
int i, count = _m1.checkVector(2);
// compute centers and average distances for each of the two point sets
for( i = 0; i < count; i++ )
{
m1c += Point2d(m1[i]);
m2c += Point2d(m2[i]);
}
// calculate the normalizing transformations for each of the point sets:
// after the transformation each set will have the mass center at the coordinate origin
// and the average distance from the origin will be ~sqrt(2).
t = 1./count;
m1c *= t;
m2c *= t;
for( i = 0; i < count; i++ )
{
scale1 += norm(Point2d(m1[i].x - m1c.x, m1[i].y - m1c.y));
scale2 += norm(Point2d(m2[i].x - m2c.x, m2[i].y - m2c.y));
}
scale1 *= t;
scale2 *= t;
if( scale1 < FLT_EPSILON || scale2 < FLT_EPSILON )
return 0;
scale1 = std::sqrt(2.)/scale1;
scale2 = std::sqrt(2.)/scale2;
Matx<double, 9, 9> A;
// form a linear system Ax=0: for each selected pair of points m1 & m2,
// the row of A(=a) represents the coefficients of equation: (m2, 1)'*F*(m1, 1) = 0
// to save computation time, we compute (At*A) instead of A and then solve (At*A)x=0.
for( i = 0; i < count; i++ )
{
double x1 = (m1[i].x - m1c.x)*scale1;
double y1 = (m1[i].y - m1c.y)*scale1;
double x2 = (m2[i].x - m2c.x)*scale2;
double y2 = (m2[i].y - m2c.y)*scale2;
Vec<double, 9> r( x2*x1, x2*y1, x2, y2*x1, y2*y1, y2, x1, y1, 1 );
A += r*r.t();
}
Vec<double, 9> W;
Matx<double, 9, 9> V;
eigen(A, W, V);
for( i = 0; i < 9; i++ )
{
if( fabs(W[i]) < DBL_EPSILON )
break;
}
if( i < 8 )
return 0;
Matx33d F0( V.val + 9*8 ); // take the last column of v as a solution of Af = 0
// make F0 singular (of rank 2) by decomposing it with SVD,
// zeroing the last diagonal element of W and then composing the matrices back.
Vec3d w;
Matx33d U;
Matx33d Vt;
SVD::compute( F0, w, U, Vt);
w[2] = 0.;
F0 = U*Matx33d::diag(w)*Vt;
// apply the transformation that is inverse
// to what we used to normalize the point coordinates
Matx33d T1( scale1, 0, -scale1*m1c.x, 0, scale1, -scale1*m1c.y, 0, 0, 1 );
Matx33d T2( scale2, 0, -scale2*m2c.x, 0, scale2, -scale2*m2c.y, 0, 0, 1 );
F0 = T2.t()*F0*T1;
// make F(3,3) = 1
if( fabs(F0(2,2)) > FLT_EPSILON )
F0 *= 1./F0(2,2);
Mat(F0).copyTo(_fmatrix);
return 1;
}
class FMEstimatorCallback CV_FINAL : public PointSetRegistrator::Callback
{
public:
bool checkSubset( InputArray _ms1, InputArray _ms2, int count ) const CV_OVERRIDE
{
Mat ms1 = _ms1.getMat(), ms2 = _ms2.getMat();
return !haveCollinearPoints(ms1, count) && !haveCollinearPoints(ms2, count);
}
int runKernel( InputArray _m1, InputArray _m2, OutputArray _model ) const CV_OVERRIDE
{
double f[9*3];
Mat m1 = _m1.getMat(), m2 = _m2.getMat();
int count = m1.checkVector(2);
Mat F(count == 7 ? 9 : 3, 3, CV_64F, f);
int n = count == 7 ? run7Point(m1, m2, F) : run8Point(m1, m2, F);
if( n == 0 )
_model.release();
else
F.rowRange(0, n*3).copyTo(_model);
return n;
}
void computeError( InputArray _m1, InputArray _m2, InputArray _model, OutputArray _err ) const CV_OVERRIDE
{
Mat __m1 = _m1.getMat(), __m2 = _m2.getMat(), __model = _model.getMat();
int i, count = __m1.checkVector(2);
const Point2f* m1 = __m1.ptr<Point2f>();
const Point2f* m2 = __m2.ptr<Point2f>();
const double* F = __model.ptr<double>();
_err.create(count, 1, CV_32F);
float* err = _err.getMat().ptr<float>();
for( i = 0; i < count; i++ )
{
double a, b, c, d1, d2, s1, s2;
a = F[0]*m1[i].x + F[1]*m1[i].y + F[2];
b = F[3]*m1[i].x + F[4]*m1[i].y + F[5];
c = F[6]*m1[i].x + F[7]*m1[i].y + F[8];
s2 = 1./(a*a + b*b);
d2 = m2[i].x*a + m2[i].y*b + c;
a = F[0]*m2[i].x + F[3]*m2[i].y + F[6];
b = F[1]*m2[i].x + F[4]*m2[i].y + F[7];
c = F[2]*m2[i].x + F[5]*m2[i].y + F[8];
s1 = 1./(a*a + b*b);
d1 = m1[i].x*a + m1[i].y*b + c;
err[i] = (float)std::max(d1*d1*s1, d2*d2*s2);
}
}
};
}
cv::Mat cv::findFundamentalMat( InputArray _points1, InputArray _points2,
int method, double ransacReprojThreshold, double confidence,
int maxIters, OutputArray _mask )
{
CV_INSTRUMENT_REGION();
Mat points1 = _points1.getMat(), points2 = _points2.getMat();
Mat m1, m2, F;
int npoints = -1;
for( int i = 1; i <= 2; i++ )
{
Mat& p = i == 1 ? points1 : points2;
Mat& m = i == 1 ? m1 : m2;
npoints = p.checkVector(2, -1, false);
if( npoints < 0 )
{
npoints = p.checkVector(3, -1, false);
if( npoints < 0 )
CV_Error(Error::StsBadArg, "The input arrays should be 2D or 3D point sets");
if( npoints == 0 )
return Mat();
convertPointsFromHomogeneous(p, p);
}
p.reshape(2, npoints).convertTo(m, CV_32F);
}
CV_Assert( m1.checkVector(2) == m2.checkVector(2) );
if( npoints < 7 )
return Mat();
Ptr<PointSetRegistrator::Callback> cb = makePtr<FMEstimatorCallback>();
int result;
if( npoints == 7 || method == FM_8POINT )
{
result = cb->runKernel(m1, m2, F);
if( _mask.needed() )
{
_mask.create(npoints, 1, CV_8U, -1, true);
Mat mask = _mask.getMat();
CV_Assert( (mask.cols == 1 || mask.rows == 1) && (int)mask.total() == npoints );
mask.setTo(Scalar::all(1));
}
}
else
{
if( ransacReprojThreshold <= 0 )
ransacReprojThreshold = 3;
if( confidence < DBL_EPSILON || confidence > 1 - DBL_EPSILON )
confidence = 0.99;
if( (method & ~3) == FM_RANSAC && npoints >= 15 )
result = createRANSACPointSetRegistrator(cb, 7, ransacReprojThreshold, confidence, maxIters)->run(m1, m2, F, _mask);
else
result = createLMeDSPointSetRegistrator(cb, 7, confidence, maxIters)->run(m1, m2, F, _mask);
}
if( result <= 0 )
return Mat();
return F;
}
cv::Mat cv::findFundamentalMat( cv::InputArray points1, cv::InputArray points2,
int method, double ransacReprojThreshold, double confidence,
cv::OutputArray mask )
{
return cv::findFundamentalMat(points1, points2, method, ransacReprojThreshold, confidence, 1000, mask);
}
cv::Mat cv::findFundamentalMat( cv::InputArray points1, cv::InputArray points2, cv::OutputArray mask,
int method, double ransacReprojThreshold, double confidence )
{
return cv::findFundamentalMat(points1, points2, method, ransacReprojThreshold, confidence, 1000, mask);
}
void cv::computeCorrespondEpilines( InputArray _points, int whichImage,
InputArray _Fmat, OutputArray _lines )
{
CV_INSTRUMENT_REGION();
double f[9] = {0};
Mat tempF(3, 3, CV_64F, f);
Mat points = _points.getMat(), F = _Fmat.getMat();
if( !points.isContinuous() )
points = points.clone();
int npoints = points.checkVector(2);
if( npoints < 0 )
{
npoints = points.checkVector(3);
if( npoints < 0 )
CV_Error( Error::StsBadArg, "The input should be a 2D or 3D point set");
Mat temp;
convertPointsFromHomogeneous(points, temp);
points = temp;
}
int depth = points.depth();
CV_Assert( depth == CV_32F || depth == CV_32S || depth == CV_64F );
CV_Assert(F.size() == Size(3,3));
F.convertTo(tempF, CV_64F);
if( whichImage == 2 )
transpose(tempF, tempF);
int ltype = CV_MAKETYPE(MAX(depth, CV_32F), 3);
_lines.create(npoints, 1, ltype);
Mat lines = _lines.getMat();
if( !lines.isContinuous() )
{
_lines.release();
_lines.create(npoints, 1, ltype);
lines = _lines.getMat();
}
CV_Assert( lines.isContinuous());
if( depth == CV_32S || depth == CV_32F )
{
const Point* ptsi = points.ptr<Point>();
const Point2f* ptsf = points.ptr<Point2f>();
Point3f* dstf = lines.ptr<Point3f>();
for( int i = 0; i < npoints; i++ )
{
Point2f pt = depth == CV_32F ? ptsf[i] : Point2f((float)ptsi[i].x, (float)ptsi[i].y);
double a = f[0]*pt.x + f[1]*pt.y + f[2];
double b = f[3]*pt.x + f[4]*pt.y + f[5];
double c = f[6]*pt.x + f[7]*pt.y + f[8];
double nu = a*a + b*b;
nu = nu ? 1./std::sqrt(nu) : 1.;
a *= nu; b *= nu; c *= nu;
dstf[i] = Point3f((float)a, (float)b, (float)c);
}
}
else
{
const Point2d* ptsd = points.ptr<Point2d>();
Point3d* dstd = lines.ptr<Point3d>();
for( int i = 0; i < npoints; i++ )
{
Point2d pt = ptsd[i];
double a = f[0]*pt.x + f[1]*pt.y + f[2];
double b = f[3]*pt.x + f[4]*pt.y + f[5];
double c = f[6]*pt.x + f[7]*pt.y + f[8];
double nu = a*a + b*b;
nu = nu ? 1./std::sqrt(nu) : 1.;
a *= nu; b *= nu; c *= nu;
dstd[i] = Point3d(a, b, c);
}
}
}
static inline double scaleFor(double x){
return (std::fabs(x) > std::numeric_limits<float>::epsilon()) ? 1./x : 1.;
}
static inline float scaleFor(float x){
return (std::fabs(x) > std::numeric_limits<float>::epsilon()) ? 1.f/x : 1.f;
}
void cv::convertPointsFromHomogeneous( InputArray _src, OutputArray _dst )
{
CV_INSTRUMENT_REGION();
Mat src = _src.getMat();
if( !src.isContinuous() )
src = src.clone();
int i, npoints = src.checkVector(3), depth = src.depth(), cn = 3;
if( npoints < 0 )
{
npoints = src.checkVector(4);
CV_Assert(npoints >= 0);
cn = 4;
}
CV_Assert( npoints >= 0 && (depth == CV_32S || depth == CV_32F || depth == CV_64F));
int dtype = CV_MAKETYPE(depth <= CV_32F ? CV_32F : CV_64F, cn-1);
_dst.create(npoints, 1, dtype);
Mat dst = _dst.getMat();
if( !dst.isContinuous() )
{
_dst.release();
_dst.create(npoints, 1, dtype);
dst = _dst.getMat();
}
CV_Assert( dst.isContinuous() );
if( depth == CV_32S )
{
if( cn == 3 )
{
const Point3i* sptr = src.ptr<Point3i>();
Point2f* dptr = dst.ptr<Point2f>();
for( i = 0; i < npoints; i++ )
{
float scale = sptr[i].z != 0 ? 1.f/sptr[i].z : 1.f;
dptr[i] = Point2f(sptr[i].x*scale, sptr[i].y*scale);
}
}
else
{
const Vec4i* sptr = src.ptr<Vec4i>();
Point3f* dptr = dst.ptr<Point3f>();
for( i = 0; i < npoints; i++ )
{
float scale = sptr[i][3] != 0 ? 1.f/sptr[i][3] : 1.f;
dptr[i] = Point3f(sptr[i][0]*scale, sptr[i][1]*scale, sptr[i][2]*scale);
}
}
}
else if( depth == CV_32F )
{
if( cn == 3 )
{
const Point3f* sptr = src.ptr<Point3f>();
Point2f* dptr = dst.ptr<Point2f>();
for( i = 0; i < npoints; i++ )
{
float scale = scaleFor(sptr[i].z);
dptr[i] = Point2f(sptr[i].x*scale, sptr[i].y*scale);
}
}
else
{
const Vec4f* sptr = src.ptr<Vec4f>();
Point3f* dptr = dst.ptr<Point3f>();
for( i = 0; i < npoints; i++ )
{
float scale = scaleFor(sptr[i][3]);
dptr[i] = Point3f(sptr[i][0]*scale, sptr[i][1]*scale, sptr[i][2]*scale);
}
}
}
else if( depth == CV_64F )
{
if( cn == 3 )
{
const Point3d* sptr = src.ptr<Point3d>();
Point2d* dptr = dst.ptr<Point2d>();
for( i = 0; i < npoints; i++ )
{
double scale = scaleFor(sptr[i].z);
dptr[i] = Point2d(sptr[i].x*scale, sptr[i].y*scale);
}
}
else
{
const Vec4d* sptr = src.ptr<Vec4d>();
Point3d* dptr = dst.ptr<Point3d>();
for( i = 0; i < npoints; i++ )
{
double scale = scaleFor(sptr[i][3]);
dptr[i] = Point3d(sptr[i][0]*scale, sptr[i][1]*scale, sptr[i][2]*scale);
}
}
}
else
CV_Error(Error::StsUnsupportedFormat, "");
}
void cv::convertPointsToHomogeneous( InputArray _src, OutputArray _dst )
{
CV_INSTRUMENT_REGION();
Mat src = _src.getMat();
if( !src.isContinuous() )
src = src.clone();
int i, npoints = src.checkVector(2), depth = src.depth(), cn = 2;
if( npoints < 0 )
{
npoints = src.checkVector(3);
CV_Assert(npoints >= 0);
cn = 3;
}
CV_Assert( npoints >= 0 && (depth == CV_32S || depth == CV_32F || depth == CV_64F));
int dtype = CV_MAKETYPE(depth, cn+1);
_dst.create(npoints, 1, dtype);
Mat dst = _dst.getMat();
if( !dst.isContinuous() )
{
_dst.release();
_dst.create(npoints, 1, dtype);
dst = _dst.getMat();
}
CV_Assert( dst.isContinuous() );
if( depth == CV_32S )
{
if( cn == 2 )
{
const Point2i* sptr = src.ptr<Point2i>();
Point3i* dptr = dst.ptr<Point3i>();
for( i = 0; i < npoints; i++ )
dptr[i] = Point3i(sptr[i].x, sptr[i].y, 1);
}
else
{
const Point3i* sptr = src.ptr<Point3i>();
Vec4i* dptr = dst.ptr<Vec4i>();
for( i = 0; i < npoints; i++ )
dptr[i] = Vec4i(sptr[i].x, sptr[i].y, sptr[i].z, 1);
}
}
else if( depth == CV_32F )
{
if( cn == 2 )
{
const Point2f* sptr = src.ptr<Point2f>();
Point3f* dptr = dst.ptr<Point3f>();
for( i = 0; i < npoints; i++ )
dptr[i] = Point3f(sptr[i].x, sptr[i].y, 1.f);
}
else
{
const Point3f* sptr = src.ptr<Point3f>();
Vec4f* dptr = dst.ptr<Vec4f>();
for( i = 0; i < npoints; i++ )
dptr[i] = Vec4f(sptr[i].x, sptr[i].y, sptr[i].z, 1.f);
}
}
else if( depth == CV_64F )
{
if( cn == 2 )
{
const Point2d* sptr = src.ptr<Point2d>();
Point3d* dptr = dst.ptr<Point3d>();
for( i = 0; i < npoints; i++ )
dptr[i] = Point3d(sptr[i].x, sptr[i].y, 1.);
}
else
{
const Point3d* sptr = src.ptr<Point3d>();
Vec4d* dptr = dst.ptr<Vec4d>();
for( i = 0; i < npoints; i++ )
dptr[i] = Vec4d(sptr[i].x, sptr[i].y, sptr[i].z, 1.);
}
}
else
CV_Error(Error::StsUnsupportedFormat, "");
}
void cv::convertPointsHomogeneous( InputArray _src, OutputArray _dst )
{
CV_INSTRUMENT_REGION();
int stype = _src.type(), dtype = _dst.type();
CV_Assert( _dst.fixedType() );
if( CV_MAT_CN(stype) > CV_MAT_CN(dtype) )
convertPointsFromHomogeneous(_src, _dst);
else
convertPointsToHomogeneous(_src, _dst);
}
double cv::sampsonDistance(InputArray _pt1, InputArray _pt2, InputArray _F)
{
CV_INSTRUMENT_REGION();
CV_Assert(_pt1.type() == CV_64F && _pt2.type() == CV_64F && _F.type() == CV_64F);
CV_DbgAssert(_pt1.rows() == 3 && _F.size() == Size(3, 3) && _pt1.rows() == _pt2.rows());
Mat pt1(_pt1.getMat());
Mat pt2(_pt2.getMat());
Mat F(_F.getMat());
Vec3d F_pt1 = *F.ptr<Matx33d>() * *pt1.ptr<Vec3d>();
Vec3d Ft_pt2 = F.ptr<Matx33d>()->t() * *pt2.ptr<Vec3d>();
double v = pt2.ptr<Vec3d>()->dot(F_pt1);
// square
Ft_pt2 = Ft_pt2.mul(Ft_pt2);
F_pt1 = F_pt1.mul(F_pt1);
return v*v / (F_pt1[0] + F_pt1[1] + Ft_pt2[0] + Ft_pt2[1]);
}
/* End of file. */