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1060 lines (875 loc) · 30.9 KB
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// This file is part of OpenCV project.
// It is subject to the license terms in the LICENSE file found in the top-level directory
// of this distribution and at http://opencv.org/license.html
#include "../precomp.hpp"
#include "opencv2/3d/detail/optimizer.hpp"
#include <opencv2/3d/mst.hpp>
#include "sparse_block_matrix.hpp"
namespace cv
{
namespace detail
{
#if defined(HAVE_EIGEN)
// matrix form of conjugation
static const cv::Matx44d M_Conj{ 1, 0, 0, 0,
0, -1, 0, 0,
0, 0, -1, 0,
0, 0, 0, -1 };
// matrix form of quaternion multiplication from left side
static inline cv::Matx44d m_left(cv::Quatd q)
{
// M_left(a)* V(b) =
// = (I_4 * a0 + [ 0 | -av [ 0 | 0_1x3
// av | 0_3] + 0_3x1 | skew(av)]) * V(b)
double w = q.w, x = q.x, y = q.y, z = q.z;
return { w, -x, -y, -z,
x, w, -z, y,
y, z, w, -x,
z, -y, x, w };
}
// matrix form of quaternion multiplication from right side
static inline cv::Matx44d m_right(cv::Quatd q)
{
// M_right(b)* V(a) =
// = (I_4 * b0 + [ 0 | -bv [ 0 | 0_1x3
// bv | 0_3] + 0_3x1 | skew(-bv)]) * V(a)
double w = q.w, x = q.x, y = q.y, z = q.z;
return { w, -x, -y, -z,
x, w, z, -y,
y, -z, w, x,
z, y, -x, w };
}
// jacobian of quaternionic (exp(x)*q) : R_3 -> H near x == 0
static inline cv::Matx43d expQuatJacobian(cv::Quatd q)
{
double w = q.w, x = q.x, y = q.y, z = q.z;
return cv::Matx43d(-x, -y, -z,
w, z, -y,
-z, w, x,
y, -x, w);
}
// concatenate matrices vertically
template<typename _Tp, int m, int n, int k> static inline
cv::Matx<_Tp, m + k, n> concatVert(const cv::Matx<_Tp, m, n>& a, const cv::Matx<_Tp, k, n>& b)
{
cv::Matx<_Tp, m + k, n> res;
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
res(i, j) = a(i, j);
}
}
for (int i = 0; i < k; i++)
{
for (int j = 0; j < n; j++)
{
res(m + i, j) = b(i, j);
}
}
return res;
}
// concatenate matrices horizontally
template<typename _Tp, int m, int n, int k> static inline
cv::Matx<_Tp, m, n + k> concatHor(const cv::Matx<_Tp, m, n>& a, const cv::Matx<_Tp, m, k>& b)
{
cv::Matx<_Tp, m, n + k> res;
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
res(i, j) = a(i, j);
}
}
for (int i = 0; i < m; i++)
{
for (int j = 0; j < k; j++)
{
res(i, n + j) = b(i, j);
}
}
return res;
}
class PoseGraphImpl;
class PoseGraphLevMarqBackend;
class PoseGraphLevMarq : public LevMarqBase
{
public:
PoseGraphLevMarq(PoseGraphImpl* pg, const LevMarq::Settings& settings_ = LevMarq::Settings()) :
LevMarqBase(makePtr<PoseGraphLevMarqBackend>(pg), settings_)
{ }
};
class PoseGraphImpl : public detail::PoseGraph
{
public:
struct Pose3d
{
Vec3d t;
Quatd q;
Pose3d() : t(), q(1, 0, 0, 0) { }
Pose3d(const Matx33d& rotation, const Vec3d& translation)
: t(translation), q(Quatd::createFromRotMat(rotation).normalize())
{ }
explicit Pose3d(const Matx44d& pose) :
Pose3d(pose.get_minor<3, 3>(0, 0), Vec3d(pose(0, 3), pose(1, 3), pose(2, 3)))
{ }
inline Pose3d operator*(const Pose3d& otherPose) const
{
Pose3d out(*this);
out.t += q.toRotMat3x3(QUAT_ASSUME_UNIT) * otherPose.t;
out.q = out.q * otherPose.q;
return out;
}
Affine3d getAffine() const
{
return Affine3d(q.toRotMat3x3(QUAT_ASSUME_UNIT), t);
}
inline Pose3d inverse() const
{
Pose3d out;
out.q = q.conjugate();
out.t = -(out.q.toRotMat3x3(QUAT_ASSUME_UNIT) * t);
return out;
}
inline void normalizeRotation()
{
q = q.normalize();
}
// jacobian of exponential (exp(x)* q) : R_6->SE(3) near x == 0
inline Matx<double, 7, 6> expJacobian()
{
Matx43d qj = expQuatJacobian(q);
// x node layout is (rot_x, rot_y, rot_z, trans_x, trans_y, trans_z)
// pose layout is (q_w, q_x, q_y, q_z, trans_x, trans_y, trans_z)
return concatVert(concatHor(qj, Matx43d()),
concatHor(Matx33d(), Matx33d::eye()));
}
inline Pose3d oplus(const Vec6d dx)
{
Vec3d deltaRot(dx[0], dx[1], dx[2]), deltaTrans(dx[3], dx[4], dx[5]);
Pose3d p;
p.q = Quatd(0, deltaRot[0], deltaRot[1], deltaRot[2]).exp() * this->q;
p.t = this->t + deltaTrans;
return p;
}
};
/*! \class GraphNode
* \brief Defines a node/variable that is optimizable in a posegraph
*
* Detailed description
*/
struct Node
{
public:
explicit Node(size_t _nodeId, const Affine3d& _pose)
: id(_nodeId), isFixed(false), pose(_pose.rotation(), _pose.translation())
{ }
Affine3d getPose() const
{
return pose.getAffine();
}
void setPose(const Affine3d& _pose)
{
pose = Pose3d(_pose.rotation(), _pose.translation());
}
public:
size_t id;
bool isFixed;
Pose3d pose;
};
/*! \class PoseGraphEdge
* \brief Defines the constraints between two PoseGraphNodes
*
* Detailed description
*/
struct Edge
{
public:
explicit Edge(size_t _sourceNodeId, size_t _targetNodeId, const Affine3f& _transformation,
const Matx66f& _information = Matx66f::eye());
bool operator==(const Edge& edge)
{
if ((edge.sourceNodeId == sourceNodeId && edge.targetNodeId == targetNodeId) ||
(edge.sourceNodeId == targetNodeId && edge.targetNodeId == sourceNodeId))
return true;
return false;
}
public:
size_t sourceNodeId;
size_t targetNodeId;
Pose3d pose;
Matx66f sqrtInfo;
};
PoseGraphImpl() : nodes(), edges(), lm()
{ }
virtual ~PoseGraphImpl() CV_OVERRIDE
{ }
// Node may have any id >= 0
virtual void addNode(size_t _nodeId, const Affine3d& _pose, bool fixed) CV_OVERRIDE;
virtual bool isNodeExist(size_t nodeId) const CV_OVERRIDE
{
return (nodes.find(nodeId) != nodes.end());
}
virtual bool setNodeFixed(size_t nodeId, bool fixed) CV_OVERRIDE
{
auto it = nodes.find(nodeId);
if (it != nodes.end())
{
it->second.isFixed = fixed;
return true;
}
else
return false;
}
virtual bool isNodeFixed(size_t nodeId) const CV_OVERRIDE
{
auto it = nodes.find(nodeId);
if (it != nodes.end())
return it->second.isFixed;
else
return false;
}
virtual Affine3d getNodePose(size_t nodeId) const CV_OVERRIDE
{
auto it = nodes.find(nodeId);
if (it != nodes.end())
return it->second.getPose();
else
return Affine3d();
}
virtual std::vector<size_t> getNodesIds() const CV_OVERRIDE
{
std::vector<size_t> ids;
for (const auto& it : nodes)
{
ids.push_back(it.first);
}
return ids;
}
virtual size_t getNumNodes() const CV_OVERRIDE
{
return nodes.size();
}
// Edges have consequent indices starting from 0
virtual void addEdge(size_t _sourceNodeId, size_t _targetNodeId, const Affine3f& _transformation,
const Matx66f& _information = Matx66f::eye()) CV_OVERRIDE
{
Edge e(_sourceNodeId, _targetNodeId, _transformation, _information);
edges.push_back(e);
}
virtual size_t getEdgeStart(size_t i) const CV_OVERRIDE
{
return edges[i].sourceNodeId;
}
virtual size_t getEdgeEnd(size_t i) const CV_OVERRIDE
{
return edges[i].targetNodeId;
}
virtual Affine3d getEdgePose(size_t i) const CV_OVERRIDE
{
return edges[i].pose.getAffine();
}
virtual Matx66f getEdgeInfo(size_t i) const CV_OVERRIDE
{
Matx66f s = edges[i].sqrtInfo;
return s * s;
}
virtual size_t getNumEdges() const CV_OVERRIDE
{
return edges.size();
}
// checks if graph is connected and each edge connects exactly 2 nodes
virtual bool isValid() const CV_OVERRIDE;
// calculate cost function based on current nodes parameters
virtual double calcEnergy() const CV_OVERRIDE;
// calculate cost function based on provided nodes parameters
double calcEnergyNodes(const std::map<size_t, Node>& newNodes) const;
void initializePosesWithMST(double lambda) CV_OVERRIDE;
// creates an optimizer
virtual Ptr<LevMarqBase> createOptimizer(const LevMarq::Settings& settings) CV_OVERRIDE
{
lm = makePtr<PoseGraphLevMarq>(this, settings);
return lm;
}
// creates an optimizer
virtual Ptr<LevMarqBase> createOptimizer() CV_OVERRIDE
{
lm = makePtr<PoseGraphLevMarq>(this, LevMarq::Settings()
.setMaxIterations(100)
.setCheckRelEnergyChange(true)
.setRelEnergyDeltaTolerance(1e-6)
.setGeodesic(true));
return lm;
}
// Returns number of iterations elapsed or -1 if max number of iterations was reached or failed to optimize
virtual LevMarq::Report optimize() CV_OVERRIDE;
std::map<size_t, Node> nodes;
std::vector<Edge> edges;
Ptr<PoseGraphLevMarq> lm;
private:
double calculateWeight(const PoseGraphImpl::Edge& e, double lambda) const;
void applyMST(const std::vector<cv::MSTEdge>& resultingEdges, const PoseGraphImpl::Node& rootNode);
};
void PoseGraphImpl::addNode(size_t _nodeId, const Affine3d& _pose, bool fixed)
{
Node node(_nodeId, _pose);
node.isFixed = fixed;
size_t id = node.id;
const auto& it = nodes.find(id);
if (it != nodes.end())
{
std::cout << "duplicated node, id=" << id << std::endl;
nodes.insert(it, { id, node });
}
else
{
nodes.insert({ id, node });
}
}
// Cholesky decomposition of symmetrical 6x6 matrix
static inline cv::Matx66d llt6(Matx66d m)
{
Matx66d L;
for (int i = 0; i < 6; i++)
{
for (int j = 0; j < (i + 1); j++)
{
double sum = 0;
for (int k = 0; k < j; k++)
sum += L(i, k) * L(j, k);
if (i == j)
L(i, i) = sqrt(m(i, i) - sum);
else
L(i, j) = (1.0 / L(j, j) * (m(i, j) - sum));
}
}
return L;
}
PoseGraphImpl::Edge::Edge(size_t _sourceNodeId, size_t _targetNodeId, const Affine3f& _transformation,
const Matx66f& _information) :
sourceNodeId(_sourceNodeId),
targetNodeId(_targetNodeId),
pose(_transformation.rotation(), _transformation.translation()),
sqrtInfo(llt6(_information))
{ }
bool PoseGraphImpl::isValid() const
{
size_t numNodes = getNumNodes();
size_t numEdges = getNumEdges();
if (!numNodes || !numEdges)
return false;
std::unordered_set<size_t> nodesVisited;
std::vector<size_t> nodesToVisit;
nodesToVisit.push_back(nodes.begin()->first);
bool isGraphConnected = false;
while (!nodesToVisit.empty())
{
size_t currNodeId = nodesToVisit.back();
nodesToVisit.pop_back();
nodesVisited.insert(currNodeId);
// Since each node does not maintain its neighbor list
for (size_t i = 0; i < numEdges; i++)
{
const Edge& potentialEdge = edges.at(i);
size_t nextNodeId = (size_t)(-1);
if (potentialEdge.sourceNodeId == currNodeId)
{
nextNodeId = potentialEdge.targetNodeId;
}
else if (potentialEdge.targetNodeId == currNodeId)
{
nextNodeId = potentialEdge.sourceNodeId;
}
if (nextNodeId != (size_t)(-1))
{
if (nodesVisited.count(nextNodeId) == 0)
{
nodesToVisit.push_back(nextNodeId);
}
}
}
}
isGraphConnected = (nodesVisited.size() == numNodes);
CV_LOG_INFO(NULL, "nodesVisited: " << nodesVisited.size() << " IsGraphConnected: " << isGraphConnected);
bool invalidEdgeNode = false;
for (size_t i = 0; i < numEdges; i++)
{
const Edge& edge = edges.at(i);
// edges have spurious source/target nodes
if ((nodesVisited.count(edge.sourceNodeId) != 1) ||
(nodesVisited.count(edge.targetNodeId) != 1))
{
invalidEdgeNode = true;
break;
}
}
return isGraphConnected && !invalidEdgeNode;
}
double PoseGraphImpl::calculateWeight(const PoseGraphImpl::Edge& e, double lambda) const
{
double translationNorm = cv::norm(e.pose.t);
cv::Matx33d R = e.pose.q.toRotMat3x3(cv::QUAT_ASSUME_UNIT);
cv::Vec3d rvec;
cv::Rodrigues(R, rvec);
double rotationAngle = cv::norm(rvec);
double weight = translationNorm + lambda * rotationAngle;
return weight;
}
void PoseGraphImpl::applyMST(const std::vector<cv::MSTEdge>& resultingEdges, const PoseGraphImpl::Node& rootNode)
{
std::unordered_map<size_t, std::vector<std::pair<size_t, PoseGraphImpl::Pose3d>>> adj;
for (const auto& e: resultingEdges)
{
auto it = std::find_if(edges.begin(), edges.end(), [&](const PoseGraphImpl::Edge& edge)
{
return (edge.sourceNodeId == static_cast<size_t>(e.source) && edge.targetNodeId == static_cast<size_t>(e.target)) ||
(edge.sourceNodeId == static_cast<size_t>(e.target) && edge.targetNodeId == static_cast<size_t>(e.source));
});
if (it != edges.end())
{
size_t src = it->sourceNodeId;
size_t tgt = it->targetNodeId;
const PoseGraphImpl::Pose3d& relPose = it->pose;
adj[src].emplace_back(tgt, relPose);
adj[tgt].emplace_back(src, relPose.inverse());
}
}
std::unordered_map<size_t, PoseGraphImpl::Pose3d> newPoses;
std::stack<size_t> toVisit;
std::unordered_set<size_t> visited;
newPoses[rootNode.id] = rootNode.pose;
toVisit.push(rootNode.id);
while (!toVisit.empty())
{
size_t current = toVisit.top();
toVisit.pop();
visited.insert(current);
const auto& currentPose = newPoses[current];
auto it = adj.find(current);
if (it == adj.end())
continue;
for (const auto& pr : it->second)
{
auto neighbor = pr.first;
auto relativePose = pr.second;
if (visited.count(neighbor))
continue;
newPoses[neighbor] = currentPose * relativePose;
toVisit.push(neighbor);
}
}
// Apply the new poses
for (const auto& np : newPoses)
{
auto nodeId = np.first;
auto pose = np.second;
if (!nodes.at(nodeId).isFixed)
nodes.at(nodeId).setPose(pose.getAffine());
}
}
void PoseGraphImpl::initializePosesWithMST(double lambda)
{
size_t numNodes = getNumNodes();
std::vector<MSTEdge> MSTedges;
for (const auto& e: edges)
{
double weight = calculateWeight(e, lambda);
MSTedges.push_back({static_cast<int>(e.sourceNodeId), static_cast<int>(e.targetNodeId), weight});
}
size_t rootId = 0;
PoseGraphImpl::Node rootNode = nodes.begin()->second;
for (const auto& n: nodes)
{
if (isNodeFixed(n.second.id))
{
rootNode = n.second;
rootId = n.second.id;
break;
}
}
std::vector<MSTEdge> resultingEdges;
if (!cv::buildMST(numNodes, MSTedges, resultingEdges, MST_PRIM, static_cast<int>(rootId)))
{
CV_LOG_INFO(NULL, "Failed to build MST: graph may be disconnected.");
return;
}
applyMST(resultingEdges, rootNode);
}
//////////////////////////
// Optimization itself //
////////////////////////
static inline double poseError(Quatd sourceQuat, Vec3d sourceTrans, Quatd targetQuat, Vec3d targetTrans,
Quatd rotMeasured, Vec3d transMeasured, Matx66d sqrtInfoMatrix, bool needJacobians,
Matx<double, 6, 4>& sqj, Matx<double, 6, 3>& stj,
Matx<double, 6, 4>& tqj, Matx<double, 6, 3>& ttj,
Vec6d& res)
{
// err_r = 2*Im(conj(rel_r) * measure_r) = 2*Im(conj(target_r) * source_r * measure_r)
// err_t = conj(source_r) * (target_t - source_t) * source_r - measure_t
Quatd sourceQuatInv = sourceQuat.conjugate();
Vec3d deltaTrans = targetTrans - sourceTrans;
Quatd relativeQuat = sourceQuatInv * targetQuat;
Vec3d relativeTrans = sourceQuatInv.toRotMat3x3(cv::QUAT_ASSUME_UNIT) * deltaTrans;
//! Definition should actually be relativeQuat * rotMeasured.conjugate()
Quatd deltaRot = relativeQuat.conjugate() * rotMeasured;
Vec3d terr = relativeTrans - transMeasured;
Vec3d rerr = 2.0 * Vec3d(deltaRot.x, deltaRot.y, deltaRot.z);
Vec6d rterr(terr[0], terr[1], terr[2], rerr[0], rerr[1], rerr[2]);
res = sqrtInfoMatrix * rterr;
if (needJacobians)
{
// d(err_r) = 2*Im(d(conj(target_r) * source_r * measure_r)) = < measure_r is constant > =
// 2*Im((conj(d(target_r)) * source_r + conj(target_r) * d(source_r)) * measure_r)
// d(target_r) == 0:
// # d(err_r) = 2*Im(conj(target_r) * d(source_r) * measure_r)
// # V(d(err_r)) = 2 * M_Im * M_right(measure_r) * M_left(conj(target_r)) * V(d(source_r))
// # d(err_r) / d(source_r) = 2 * M_Im * M_right(measure_r) * M_left(conj(target_r))
Matx34d drdsq = 2.0 * (m_right(rotMeasured) * m_left(targetQuat.conjugate())).get_minor<3, 4>(1, 0);
// d(source_r) == 0:
// # d(err_r) = 2*Im(conj(d(target_r)) * source_r * measure_r)
// # V(d(err_r)) = 2 * M_Im * M_right(source_r * measure_r) * M_Conj * V(d(target_r))
// # d(err_r) / d(target_r) = 2 * M_Im * M_right(source_r * measure_r) * M_Conj
Matx34d drdtq = 2.0 * (m_right(sourceQuat * rotMeasured) * M_Conj).get_minor<3, 4>(1, 0);
// d(err_t) = d(conj(source_r) * (target_t - source_t) * source_r) =
// conj(source_r) * (d(target_t) - d(source_t)) * source_r +
// conj(d(source_r)) * (target_t - source_t) * source_r +
// conj(source_r) * (target_t - source_t) * d(source_r) =
// <conj(a*b) == conj(b)*conj(a), conj(target_t - source_t) = - (target_t - source_t), 2 * Im(x) = (x - conj(x))>
// conj(source_r) * (d(target_t) - d(source_t)) * source_r +
// 2 * Im(conj(source_r) * (target_t - source_t) * d(source_r))
// d(*_t) == 0:
// # d(err_t) = 2 * Im(conj(source_r) * (target_t - source_t) * d(source_r))
// # V(d(err_t)) = 2 * M_Im * M_left(conj(source_r) * (target_t - source_t)) * V(d(source_r))
// # d(err_t) / d(source_r) = 2 * M_Im * M_left(conj(source_r) * (target_t - source_t))
Matx34d dtdsq = 2 * m_left(sourceQuatInv * Quatd(0, deltaTrans[0], deltaTrans[1], deltaTrans[2])).get_minor<3, 4>(1, 0);
// deltaTrans is rotated by sourceQuatInv, so the jacobian is rot matrix of sourceQuatInv by +1 or -1
Matx33d dtdtt = sourceQuatInv.toRotMat3x3(QUAT_ASSUME_UNIT);
Matx33d dtdst = -dtdtt;
Matx33d z;
sqj = concatVert(dtdsq, drdsq);
tqj = concatVert(Matx34d(), drdtq);
stj = concatVert(dtdst, z);
ttj = concatVert(dtdtt, z);
stj = sqrtInfoMatrix * stj;
ttj = sqrtInfoMatrix * ttj;
sqj = sqrtInfoMatrix * sqj;
tqj = sqrtInfoMatrix * tqj;
}
return res.ddot(res);
}
double PoseGraphImpl::calcEnergy() const
{
return calcEnergyNodes(nodes);
}
// estimate current energy
double PoseGraphImpl::calcEnergyNodes(const std::map<size_t, Node>& newNodes) const
{
double totalErr = 0;
for (const auto& e : edges)
{
Pose3d srcP = newNodes.at(e.sourceNodeId).pose;
Pose3d tgtP = newNodes.at(e.targetNodeId).pose;
Vec6d res;
Matx<double, 6, 3> stj, ttj;
Matx<double, 6, 4> sqj, tqj;
double err = poseError(srcP.q, srcP.t, tgtP.q, tgtP.t, e.pose.q, e.pose.t, e.sqrtInfo,
/* needJacobians = */ false, sqj, stj, tqj, ttj, res);
totalErr += err;
}
return totalErr * 0.5;
}
// J := J * d_inv, d_inv = make_diag(di)
// J^T*J := (J * d_inv)^T * J * d_inv = diag(di) * (J^T * J) * diag(di) = eltwise_mul(J^T*J, di*di^T)
// J^T*b := (J * d_inv)^T * b = d_inv^T * J^T*b = eltwise_mul(J^T*b, di)
static void doJacobiScalingSparse(BlockSparseMat<double, 6, 6>& jtj, Mat_<double>& jtb, const Mat_<double>& di)
{
// scaling J^T*J
for (auto& ijv : jtj.ijValue)
{
Point2i bpt = ijv.first;
Matx66d& m = ijv.second;
for (int i = 0; i < 6; i++)
{
for (int j = 0; j < 6; j++)
{
Point2i pt(bpt.x * 6 + i, bpt.y * 6 + j);
m(i, j) *= di(pt.x) * di(pt.y);
}
}
}
// scaling J^T*b
jtb = jtb.mul(di);
}
//TODO: robustness
class PoseGraphLevMarqBackend : public detail::LevMarqBackend
{
public:
PoseGraphLevMarqBackend(PoseGraphImpl* pg_) :
LevMarqBackend(),
pg(pg_),
jtj(0),
jtb(),
tempNodes(),
useGeo(),
geoNodes(),
jtrvv(),
jtCached(),
decomposition(),
numNodes(),
numEdges(),
placesIds(),
idToPlace(),
nVarNodes()
{
if (!pg->isValid())
{
CV_Error(cv::Error::Code::StsBadArg, "Invalid PoseGraph that is either not connected or has invalid nodes");
}
this->numNodes = pg->getNumNodes();
this->numEdges = pg->getNumEdges();
// Allocate indices for nodes
for (const auto& ni : pg->nodes)
{
if (!ni.second.isFixed)
{
this->idToPlace[ni.first] = this->placesIds.size();
this->placesIds.push_back(ni.first);
}
}
this->nVarNodes = this->placesIds.size();
if (!this->nVarNodes)
{
CV_Error(cv::Error::Code::StsBadArg, "PoseGraph contains no non-constant nodes, skipping optimization");
}
if (!this->numEdges)
{
CV_Error(cv::Error::Code::StsBadArg, "PoseGraph has no edges, no optimization to be done");
}
CV_LOG_INFO(NULL, "Optimizing PoseGraph with " << this->numNodes << " nodes and " << this->numEdges << " edges");
this->nVars = this->nVarNodes * 6;
}
virtual bool calcFunc(double& energy, bool calcEnergy = true, bool calcJacobian = false) CV_OVERRIDE
{
std::map<size_t, PoseGraphImpl::Node>& nodes = tempNodes;
std::vector<cv::Matx<double, 7, 6>> cachedJac;
if (calcJacobian)
{
jtj.clear();
std::fill(jtb.begin(), jtb.end(), 0.0);
// caching nodes jacobians
for (auto id : placesIds)
{
cachedJac.push_back(nodes.at(id).pose.expJacobian());
}
if (useGeo)
jtCached.clear();
}
double totalErr = 0.0;
for (const auto& e : pg->edges)
{
size_t srcId = e.sourceNodeId, dstId = e.targetNodeId;
const PoseGraphImpl::Node& srcNode = nodes.at(srcId);
const PoseGraphImpl::Node& dstNode = nodes.at(dstId);
const PoseGraphImpl::Pose3d& srcP = srcNode.pose;
const PoseGraphImpl::Pose3d& tgtP = dstNode.pose;
bool srcFixed = srcNode.isFixed;
bool dstFixed = dstNode.isFixed;
Vec6d res;
Matx<double, 6, 3> stj, ttj;
Matx<double, 6, 4> sqj, tqj;
double err = poseError(srcP.q, srcP.t, tgtP.q, tgtP.t, e.pose.q, e.pose.t, e.sqrtInfo,
/* needJacobians = */ calcJacobian, sqj, stj, tqj, ttj, res);
totalErr += err;
if (calcJacobian)
{
size_t srcPlace = (size_t)(-1), dstPlace = (size_t)(-1);
Matx66d sj, tj;
if (!srcFixed)
{
srcPlace = idToPlace.at(srcId);
sj = concatHor(sqj, stj) * cachedJac[srcPlace];
jtj.refBlock(srcPlace, srcPlace) += sj.t() * sj;
Vec6d jtbSrc = sj.t() * res;
for (int i = 0; i < 6; i++)
{
jtb(6 * (int)srcPlace + i) += jtbSrc[i];
}
}
if (!dstFixed)
{
dstPlace = idToPlace.at(dstId);
tj = concatHor(tqj, ttj) * cachedJac[dstPlace];
jtj.refBlock(dstPlace, dstPlace) += tj.t() * tj;
Vec6d jtbDst = tj.t() * res;
for (int i = 0; i < 6; i++)
{
jtb(6 * (int)dstPlace + i) += jtbDst[i];
}
}
if (!(srcFixed || dstFixed))
{
Matx66d sjttj = sj.t() * tj;
jtj.refBlock(srcPlace, dstPlace) += sjttj;
jtj.refBlock(dstPlace, srcPlace) += sjttj.t();
}
if (useGeo)
{
jtCached.push_back({ sj, tj });
}
}
}
if (calcEnergy)
{
energy = totalErr * 0.5;
}
return true;
}
virtual bool enableGeo() CV_OVERRIDE
{
useGeo = true;
return true;
}
// adds d to current variables and writes result to probe vars or geo vars
virtual void currentOplusX(const Mat_<double>& d, bool geo = false) CV_OVERRIDE
{
if (geo && !useGeo)
{
CV_Error(cv::Error::StsBadArg, "Geodesic acceleration is disabled");
}
std::map<size_t, PoseGraphImpl::Node>& nodes = geo ? geoNodes : tempNodes;
nodes = pg->nodes;
for (size_t i = 0; i < nVarNodes; i++)
{
Vec6d dx(d[0] + (i * 6));
PoseGraphImpl::Pose3d& p = nodes.at(placesIds[i]).pose;
p = p.oplus(dx);
}
}
virtual void prepareVars() CV_OVERRIDE
{
jtj = BlockSparseMat<double, 6, 6>(nVarNodes);
jtb = Mat_<double>((int)nVars, 1);
tempNodes = pg->nodes;
if (useGeo)
geoNodes = pg->nodes;
}
// decomposes LevMarq matrix before solution
virtual bool decompose() CV_OVERRIDE
{
return jtj.decompose(decomposition, false);
}
// solves LevMarq equation (J^T*J + lmdiag) * x = -right for current iteration using existing decomposition
// right can be equal to J^T*b for LevMarq equation or J^T*rvv for geodesic acceleration equation
virtual bool solveDecomposed(const Mat_<double>& right, Mat_<double>& x) CV_OVERRIDE
{
return jtj.solveDecomposed(decomposition, -right, x);
}
// calculates J^T*f(geo)
virtual bool calcJtbv(Mat_<double>& jtbv) CV_OVERRIDE
{
jtbv.setZero();
int ei = 0;
for (const auto& e : pg->edges)
{
size_t srcId = e.sourceNodeId, dstId = e.targetNodeId;
const PoseGraphImpl::Node& srcNode = geoNodes.at(srcId);
const PoseGraphImpl::Node& dstNode = geoNodes.at(dstId);
const PoseGraphImpl::Pose3d& srcP = srcNode.pose;
const PoseGraphImpl::Pose3d& tgtP = dstNode.pose;
bool srcFixed = srcNode.isFixed;
bool dstFixed = dstNode.isFixed;
Vec6d res;
// dummy vars
Matx<double, 6, 3> stj, ttj;
Matx<double, 6, 4> sqj, tqj;
poseError(srcP.q, srcP.t, tgtP.q, tgtP.t, e.pose.q, e.pose.t, e.sqrtInfo,
/* needJacobians = */ false, sqj, stj, tqj, ttj, res);
size_t srcPlace = (size_t)(-1), dstPlace = (size_t)(-1);
Matx66d sj = jtCached[ei].first, tj = jtCached[ei].second;
if (!srcFixed)
{
srcPlace = idToPlace.at(srcId);
Vec6d jtbSrc = sj.t() * res;
for (int i = 0; i < 6; i++)
{
jtbv(6 * (int)srcPlace + i) += jtbSrc[i];
}
}
if (!dstFixed)
{
dstPlace = idToPlace.at(dstId);
Vec6d jtbDst = tj.t() * res;
for (int i = 0; i < 6; i++)
{
jtbv(6 * (int)dstPlace + i) += jtbDst[i];
}
}
ei++;
}
return true;
}
virtual const Mat_<double> getDiag() CV_OVERRIDE
{
return jtj.diagonal();
}
virtual const Mat_<double> getJtb() CV_OVERRIDE
{
return jtb;
}
virtual void setDiag(const Mat_<double>& d) CV_OVERRIDE
{
for (size_t i = 0; i < nVars; i++)
{
jtj.refElem(i, i) = d((int)i);
}
}
virtual void doJacobiScaling(const Mat_<double>& di) CV_OVERRIDE
{
doJacobiScalingSparse(jtj, jtb, di);
}
virtual void acceptProbe() CV_OVERRIDE
{