blender/extern/libmv/third_party/ssba/Geometry/v3d_metricbundle.cpp
Sergey Sharybin 6fbc4186fd Assorted camera tracker improvements
- Add support for refining the camera's intrinsic parameters
  during a solve. Currently, refining supports only the following
  combinations of intrinsic parameters:

    f
    f, cx, cy
    f, cx, cy, k1, k2
    f, k1
    f, k1, k2

  This is not the same as autocalibration, since the user must
  still make a reasonable initial guess about the focal length and
  other parameters, whereas true autocalibration would eliminate
  the need for the user specify intrinsic parameters at all.

  However, the solver works well with only rough guesses for the
  focal length, so perhaps full autocalibation is not that
  important.

  Adding support for the last two combinations, (f, k1) and (f,
  k1, k2) required changes to the library libmv depends on for
  bundle adjustment, SSBA. These changes should get ported
  upstream not just to libmv but to SSBA as well.

- Improved the region of convergence for bundle adjustment by
  increasing the number of Levenberg-Marquardt iterations from 50
  to 500. This way, the solver is able to crawl out of the bad
  local minima it gets stuck in when changing from, for example,
  bundling k1 and k2 to just k1 and resetting k2 to 0.

- Add several new region tracker implementations. A region tracker
  is a libmv concept, which refers to tracking a template image
  pattern through frames. The impact to end users is that tracking
  should "just work better". I am reserving a more detailed
  writeup, and maybe a paper, for later.

- Other libmv tweaks, such as detecting that a tracker is headed
  outside of the image bounds.

This includes several changes made directly to the libmv extern
code rather expecting to get those changes through normal libmv
channels, because I, the libmv BDFL, decided it was faster to work
on libmv directly in Blender, then later reverse-port the libmv
changes from Blender back into libmv trunk. The interesting part
is that I added a full Levenberg-Marquardt loop to the region
tracking code, which should lead to a more stable solutions. I
also added a hacky implementation of "Efficient Second-Order
Minimization" for tracking, which works nicely. A more detailed
quantitative evaluation will follow.

Original patch by Keir, cleaned a bit by myself.
2011-11-14 06:41:23 +00:00

406 lines
13 KiB
C++

/*
Copyright (c) 2008 University of North Carolina at Chapel Hill
This file is part of SSBA (Simple Sparse Bundle Adjustment).
SSBA is free software: you can redistribute it and/or modify it under the
terms of the GNU Lesser General Public License as published by the Free
Software Foundation, either version 3 of the License, or (at your option) any
later version.
SSBA is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
details.
You should have received a copy of the GNU Lesser General Public License along
with SSBA. If not, see <http://www.gnu.org/licenses/>.
*/
#include "Geometry/v3d_metricbundle.h"
#if defined(V3DLIB_ENABLE_SUITESPARSE)
namespace
{
typedef V3D::InlineMatrix<double, 2, 4> Matrix2x4d;
typedef V3D::InlineMatrix<double, 4, 2> Matrix4x2d;
typedef V3D::InlineMatrix<double, 2, 6> Matrix2x6d;
} // end namespace <>
namespace V3D
{
void
MetricBundleOptimizerBase::updateParametersA(VectorArray<double> const& deltaAi)
{
Vector3d T, omega;
Matrix3x3d R0, dR;
for (int i = _nNonvaryingA; i < _nParametersA; ++i)
{
T = _cams[i].getTranslation();
T[0] += deltaAi[i][0];
T[1] += deltaAi[i][1];
T[2] += deltaAi[i][2];
_cams[i].setTranslation(T);
// Create incremental rotation using Rodriguez formula.
R0 = _cams[i].getRotation();
omega[0] = deltaAi[i][3];
omega[1] = deltaAi[i][4];
omega[2] = deltaAi[i][5];
createRotationMatrixRodriguez(omega, dR);
_cams[i].setRotation(dR * R0);
} // end for (i)
} // end MetricBundleOptimizerBase::updateParametersA()
void
MetricBundleOptimizerBase::updateParametersB(VectorArray<double> const& deltaBj)
{
for (int j = _nNonvaryingB; j < _nParametersB; ++j)
{
_Xs[j][0] += deltaBj[j][0];
_Xs[j][1] += deltaBj[j][1];
_Xs[j][2] += deltaBj[j][2];
}
} // end MetricBundleOptimizerBase::updateParametersB()
void
MetricBundleOptimizerBase::poseDerivatives(int i, int j, Vector3d& XX,
Matrix3x6d& d_dRT, Matrix3x3d& d_dX) const
{
XX = _cams[i].transformPointIntoCameraSpace(_Xs[j]);
// See Frank Dellaerts bundle adjustment tutorial.
// d(dR * R0 * X + t)/d omega = -[R0 * X]_x
Matrix3x3d J;
makeCrossProductMatrix(XX - _cams[i].getTranslation(), J);
scaleMatrixIP(-1.0, J);
// Now the transformation from world coords into camera space is xx = Rx + T
// Hence the derivative of x wrt. T is just the identity matrix.
makeIdentityMatrix(d_dRT);
copyMatrixSlice(J, 0, 0, 3, 3, d_dRT, 0, 3);
// The derivative of Rx+T wrt x is just R.
copyMatrix(_cams[i].getRotation(), d_dX);
} // end MetricBundleOptimizerBase::poseDerivatives()
//----------------------------------------------------------------------
void
StdMetricBundleOptimizer::fillJacobians(Matrix<double>& Ak,
Matrix<double>& Bk,
Matrix<double>& Ck,
int i, int j, int k)
{
Vector3d XX;
Matrix3x6d d_dRT;
Matrix3x3d d_dX;
this->poseDerivatives(i, j, XX, d_dRT, d_dX);
double const f = _cams[i].getFocalLength();
double const ar = _cams[i].getAspectRatio();
Matrix2x3d dp_dX;
double const bx = f / (XX[2] * XX[2]);
double const by = ar * bx;
dp_dX[0][0] = bx * XX[2]; dp_dX[0][1] = 0; dp_dX[0][2] = -bx * XX[0];
dp_dX[1][0] = 0; dp_dX[1][1] = by * XX[2]; dp_dX[1][2] = -by * XX[1];
multiply_A_B(dp_dX, d_dRT, Ak);
multiply_A_B(dp_dX, d_dX, Bk);
} // end StdMetricBundleOptimizer::fillJacobians()
//----------------------------------------------------------------------
void
CommonInternalsMetricBundleOptimizer::fillJacobians(Matrix<double>& Ak,
Matrix<double>& Bk,
Matrix<double>& Ck,
int i, int j, int k)
{
double const focalLength = _K[0][0];
Vector3d XX;
Matrix3x6d dXX_dRT;
Matrix3x3d dXX_dX;
this->poseDerivatives(i, j, XX, dXX_dRT, dXX_dX);
Vector2d xu; // undistorted image point
xu[0] = XX[0] / XX[2];
xu[1] = XX[1] / XX[2];
Vector2d const xd = _distortion(xu); // distorted image point
Matrix2x2d dp_dxd;
dp_dxd[0][0] = focalLength; dp_dxd[0][1] = 0;
dp_dxd[1][0] = 0; dp_dxd[1][1] = _cachedAspectRatio * focalLength;
{
// First, lets do the derivative wrt the structure and motion parameters.
Matrix2x3d dxu_dXX;
dxu_dXX[0][0] = 1.0f / XX[2]; dxu_dXX[0][1] = 0; dxu_dXX[0][2] = -XX[0]/(XX[2]*XX[2]);
dxu_dXX[1][0] = 0; dxu_dXX[1][1] = 1.0f / XX[2]; dxu_dXX[1][2] = -XX[1]/(XX[2]*XX[2]);
Matrix2x2d dxd_dxu = _distortion.derivativeWrtUndistortedPoint(xu);
Matrix2x2d dp_dxu = dp_dxd * dxd_dxu;
Matrix2x3d dp_dXX = dp_dxu * dxu_dXX;
multiply_A_B(dp_dXX, dXX_dRT, Ak);
multiply_A_B(dp_dXX, dXX_dX, Bk);
} // end scope
switch (_mode)
{
case FULL_BUNDLE_FOCAL_AND_RADIAL_K1:
{
// Focal length.
Ck[0][0] = xd[0];
Ck[1][0] = xd[1];
// For radial, k1 only.
Matrix2x2d dxd_dk1k2 = _distortion.derivativeWrtRadialParameters(xu);
Matrix2x2d d_dk1k2 = dp_dxd * dxd_dk1k2;
Ck[0][1] = d_dk1k2[0][0];
Ck[1][1] = d_dk1k2[1][0];
break;
}
case FULL_BUNDLE_FOCAL_AND_RADIAL:
{
// Focal length.
Ck[0][0] = xd[0];
Ck[1][0] = xd[1];
// Radial k1 and k2.
Matrix2x2d dxd_dk1k2 = _distortion.derivativeWrtRadialParameters(xu);
Matrix2x2d d_dk1k2 = dp_dxd * dxd_dk1k2;
copyMatrixSlice(d_dk1k2, 0, 0, 2, 2, Ck, 0, 1);
break;
}
case FULL_BUNDLE_RADIAL_TANGENTIAL:
{
Matrix2x2d dxd_dp1p2 = _distortion.derivativeWrtTangentialParameters(xu);
Matrix2x2d d_dp1p2 = dp_dxd * dxd_dp1p2;
copyMatrixSlice(d_dp1p2, 0, 0, 2, 2, Ck, 0, 5);
// No break here!
}
case FULL_BUNDLE_RADIAL:
{
Matrix2x2d dxd_dk1k2 = _distortion.derivativeWrtRadialParameters(xu);
Matrix2x2d d_dk1k2 = dp_dxd * dxd_dk1k2;
copyMatrixSlice(d_dk1k2, 0, 0, 2, 2, Ck, 0, 3);
// No break here!
}
case FULL_BUNDLE_FOCAL_LENGTH_PP:
{
Ck[0][1] = 1; Ck[0][2] = 0;
Ck[1][1] = 0; Ck[1][2] = 1;
// No break here!
}
case FULL_BUNDLE_FOCAL_LENGTH:
{
Ck[0][0] = xd[0];
Ck[1][0] = xd[1];
}
case FULL_BUNDLE_METRIC:
{
}
} // end switch
} // end CommonInternalsMetricBundleOptimizer::fillJacobians()
void
CommonInternalsMetricBundleOptimizer::updateParametersC(Vector<double> const& deltaC)
{
switch (_mode)
{
case FULL_BUNDLE_FOCAL_AND_RADIAL_K1:
{
_K[0][0] += deltaC[0];
_K[1][1] = _cachedAspectRatio * _K[0][0];
_distortion.k1 += deltaC[1];
break;
}
case FULL_BUNDLE_FOCAL_AND_RADIAL:
{
_K[0][0] += deltaC[0];
_K[1][1] = _cachedAspectRatio * _K[0][0];
_distortion.k1 += deltaC[1];
_distortion.k2 += deltaC[2];
break;
}
case FULL_BUNDLE_RADIAL_TANGENTIAL:
{
_distortion.p1 += deltaC[5];
_distortion.p2 += deltaC[6];
// No break here!
}
case FULL_BUNDLE_RADIAL:
{
_distortion.k1 += deltaC[3];
_distortion.k2 += deltaC[4];
// No break here!
}
case FULL_BUNDLE_FOCAL_LENGTH_PP:
{
_K[0][2] += deltaC[1];
_K[1][2] += deltaC[2];
// No break here!
}
case FULL_BUNDLE_FOCAL_LENGTH:
{
_K[0][0] += deltaC[0];
_K[1][1] = _cachedAspectRatio * _K[0][0];
}
case FULL_BUNDLE_METRIC:
{
}
} // end switch
} // end CommonInternalsMetricBundleOptimizer::updateParametersC()
//----------------------------------------------------------------------
void
VaryingInternalsMetricBundleOptimizer::fillJacobians(Matrix<double>& Ak,
Matrix<double>& Bk,
Matrix<double>& Ck,
int i, int j, int k)
{
Vector3d XX;
Matrix3x6d dXX_dRT;
Matrix3x3d dXX_dX;
this->poseDerivatives(i, j, XX, dXX_dRT, dXX_dX);
Vector2d xu; // undistorted image point
xu[0] = XX[0] / XX[2];
xu[1] = XX[1] / XX[2];
Vector2d const xd = _distortions[i](xu); // distorted image point
double const focalLength = _cams[i].getFocalLength();
double const aspectRatio = _cams[i].getAspectRatio();
Matrix2x2d dp_dxd;
dp_dxd[0][0] = focalLength; dp_dxd[0][1] = 0;
dp_dxd[1][0] = 0; dp_dxd[1][1] = aspectRatio * focalLength;
{
// First, lets do the derivative wrt the structure and motion parameters.
Matrix2x3d dxu_dXX;
dxu_dXX[0][0] = 1.0f / XX[2]; dxu_dXX[0][1] = 0; dxu_dXX[0][2] = -XX[0]/(XX[2]*XX[2]);
dxu_dXX[1][0] = 0; dxu_dXX[1][1] = 1.0f / XX[2]; dxu_dXX[1][2] = -XX[1]/(XX[2]*XX[2]);
Matrix2x2d dxd_dxu = _distortions[i].derivativeWrtUndistortedPoint(xu);
Matrix2x2d dp_dxu = dp_dxd * dxd_dxu;
Matrix2x3d dp_dXX = dp_dxu * dxu_dXX;
Matrix2x6d dp_dRT;
multiply_A_B(dp_dXX, dXX_dRT, dp_dRT);
copyMatrixSlice(dp_dRT, 0, 0, 2, 6, Ak, 0, 0);
multiply_A_B(dp_dXX, dXX_dX, Bk);
} // end scope
switch (_mode)
{
case FULL_BUNDLE_RADIAL_TANGENTIAL:
{
Matrix2x2d dxd_dp1p2 = _distortions[i].derivativeWrtTangentialParameters(xu);
Matrix2x2d d_dp1p2 = dp_dxd * dxd_dp1p2;
copyMatrixSlice(d_dp1p2, 0, 0, 2, 2, Ak, 0, 11);
// No break here!
}
case FULL_BUNDLE_RADIAL:
{
Matrix2x2d dxd_dk1k2 = _distortions[i].derivativeWrtRadialParameters(xu);
Matrix2x2d d_dk1k2 = dp_dxd * dxd_dk1k2;
copyMatrixSlice(d_dk1k2, 0, 0, 2, 2, Ak, 0, 9);
// No break here!
}
case FULL_BUNDLE_FOCAL_LENGTH_PP:
{
Ak[0][7] = 1; Ak[0][8] = 0;
Ak[1][7] = 0; Ak[1][8] = 1;
// No break here!
}
case FULL_BUNDLE_FOCAL_LENGTH:
{
Ak[0][6] = xd[0];
Ak[1][6] = xd[1];
}
case FULL_BUNDLE_METRIC:
{
}
} // end switch
} // end VaryingInternalsMetricBundleOptimizer::fillJacobians()
void
VaryingInternalsMetricBundleOptimizer::updateParametersA(VectorArray<double> const& deltaAi)
{
Vector3d T, omega;
Matrix3x3d R0, dR, K;
for (int i = _nNonvaryingA; i < _nParametersA; ++i)
{
Vector<double> const& deltaA = deltaAi[i];
T = _cams[i].getTranslation();
T[0] += deltaA[0];
T[1] += deltaA[1];
T[2] += deltaA[2];
_cams[i].setTranslation(T);
// Create incremental rotation using Rodriguez formula.
R0 = _cams[i].getRotation();
omega[0] = deltaA[3];
omega[1] = deltaA[4];
omega[2] = deltaA[5];
createRotationMatrixRodriguez(omega, dR);
_cams[i].setRotation(dR * R0);
K = _cams[i].getIntrinsic();
switch (_mode)
{
case FULL_BUNDLE_RADIAL_TANGENTIAL:
{
_distortions[i].p1 += deltaA[11];
_distortions[i].p2 += deltaA[12];
// No break here!
}
case FULL_BUNDLE_RADIAL:
{
_distortions[i].k1 += deltaA[9];
_distortions[i].k2 += deltaA[10];
// No break here!
}
case FULL_BUNDLE_FOCAL_LENGTH_PP:
{
K[0][2] += deltaA[7];
K[1][2] += deltaA[8];
// No break here!
}
case FULL_BUNDLE_FOCAL_LENGTH:
{
double const ar = K[1][1] / K[0][0];
K[0][0] += deltaA[6];
K[1][1] = ar * K[0][0];
}
case FULL_BUNDLE_METRIC:
{
}
} // end switch
_cams[i].setIntrinsic(K);
} // end for (i)
} // end VaryingInternalsMetricBundleOptimizer::updateParametersC()
} // end namespace V3D
#endif // defined(V3DLIB_ENABLE_SUITESPARSE)