/** Function for computing the potentials of the nodes and the edges in
* the graph.
*/
void computePotentials()
{
// Method steps:
// 1. Compute node potentials
// 2. Compute edge potentials
//
// 1. Node potentials
//
std::vector<CNodePtr>::iterator it;
//cout << "NODE POTENTIALS" << endl;
for ( it = m_nodes.begin(); it != m_nodes.end(); it++ )
{
CNodePtr nodePtr = *it;
if ( !nodePtr->finalPotentials() )
{
// Get the node type
//size_t type = nodePtr->getType()->getID();
// Compute the node potentials according to the node type and its
// extracted features
Eigen::VectorXd potentials = nodePtr->getType()->computePotentials( nodePtr->getFeatures() );
// Apply the node class multipliers
potentials = potentials.cwiseProduct( nodePtr->getClassMultipliers() );
/*Eigen::VectorXd fixed = nodePtr->getFixed();
potentials = potentials.cwiseProduct( fixed );*/
nodePtr->setPotentials( potentials );
}
}
//
// 2. Edge potentials
//
std::vector<CEdgePtr>::iterator it2;
//cout << "EDGE POTENTIALS" << endl;
for ( it2 = m_edges.begin(); it2 != m_edges.end(); it2++ )
{
CEdgePtr edgePtr = *it2;
Eigen::MatrixXd potentials
= edgePtr->getType()->computePotentials( edgePtr->getFeatures() );
edgePtr->setPotentials ( potentials );
}
}
void UPGMpp::applyMaskToPotentials(CGraph &graph, map<size_t,vector<size_t> > &mask )
{
vector<CNodePtr> &nodes = graph.getNodes();
for ( size_t node_index = 0; node_index < nodes.size(); node_index++ )
{
CNodePtr nodePtr = nodes[node_index];
size_t nodeID = nodePtr->getID();
if ( mask.count(nodeID) )
{
Eigen::VectorXd nodePot = nodePtr->getPotentials();
Eigen::VectorXd potMask( nodePot.rows() );
potMask.fill(0);
for ( size_t mask_index = 0; mask_index < mask[nodeID].size(); mask_index++ )
potMask(mask[nodeID][mask_index]) = 1;
nodePot = nodePot.cwiseProduct(potMask);
nodePtr->setPotentials( nodePot );
}
}
}
/** Method for getting a bound graph from the one stored into the object.
* \param boundGraph: resulting graph, it must be empty when the method
* is called.
* \param nodesToBound: a map containing as key the id of a node, and
* as value the class/state to be bound.
*/
void getBoundGraph( CGraph &boundGraph,
std::map<size_t,size_t> nodesToBound )
{
// Check that the graph is empty
assert( boundGraph.getNodes().size() == 0 );
// Copy the graph into boundGraph
// Copy nodes
for ( size_t node = 0; node < m_nodes.size(); node++ )
{
CNodePtr nodePtr(new CNode(*m_nodes[node]));
boundGraph.addNode( nodePtr );
}
// Copy edges
for ( size_t edge = 0; edge < m_edges.size(); edge++ )
{
CEdgePtr edgePtr( new CEdge(*m_edges[edge]));
boundGraph.addEdge( edgePtr );
}
// Okey, now iterate over the nodes to be bound, removing then from
// the resulting graph by expanding the potential associated with
// their bound state
for ( std::map<size_t,size_t>::iterator it = nodesToBound.begin();
it != nodesToBound.end();
it++ )
{
size_t nodeID = it->first;
size_t nodeState = it->second;
// Potential of the state to be bounded
double nodePotential = boundGraph.getNodeWithID( nodeID )->getPotentials()( nodeState );
// Iterate over the neighbours, updating their node potentials
// according to the state of the node to be bound and its potential
pair<multimap<size_t,CEdgePtr>::iterator,multimap<size_t,CEdgePtr>::iterator > neighbors;
neighbors = boundGraph.getEdgesF().equal_range(nodeID);
for ( multimap<size_t,CEdgePtr>::iterator it = neighbors.first;
it != neighbors.second;
it++ )
{
CEdgePtr edgePtr( (*it).second );
Eigen::MatrixXd edgePotentials = edgePtr->getPotentials();
size_t ID1, ID2;
edgePtr->getNodesID(ID1,ID2);
// If the node to be bound is the first one appearing in the
// edge.
if ( ID1 == nodeID )
{
CNodePtr nodePtr = boundGraph.getNodeWithID( ID2 );
Eigen::VectorXd boundPotentials = edgePotentials.row(nodeState).transpose()*nodePotential;
Eigen::VectorXd newPotentials = nodePtr->getPotentials().cwiseProduct(boundPotentials);
nodePtr->setPotentials( newPotentials );
}
else // If it is the second one in the edge
{
CNodePtr nodePtr = boundGraph.getNodeWithID( ID1 );
Eigen::VectorXd boundPotentials = edgePotentials.col( nodeState )*nodePotential;
Eigen::VectorXd newPotentials = nodePtr->getPotentials().cwiseProduct(boundPotentials);
nodePtr->setPotentials( newPotentials );
}
}
// Now that the potential of the state of the node to bound
// has been expanded, delete the node from the graph.
boundGraph.deleteNode( nodeID );
}
}
