void LocalMapping::MapPointCulling()
{
// Check Recent Added MapPoints
list<MapPoint*>::iterator lit = mlpRecentAddedMapPoints.begin();
const unsigned long int nCurrentKFid = mpCurrentKeyFrame->mnId;
while(lit!=mlpRecentAddedMapPoints.end())
{
MapPoint* pMP = *lit;
if(pMP->isBad())
{
lit = mlpRecentAddedMapPoints.erase(lit);
}
else if(pMP->GetFoundRatio()<0.25f )
{
pMP->SetBadFlag();
lit = mlpRecentAddedMapPoints.erase(lit);
}
else if((nCurrentKFid-pMP->mnFirstKFid)>=2 && pMP->Observations()<=2)
{
pMP->SetBadFlag();
lit = mlpRecentAddedMapPoints.erase(lit);
}
else if((nCurrentKFid-pMP->mnFirstKFid)>=3)
lit = mlpRecentAddedMapPoints.erase(lit);
else
lit++;
}
}
void LocalMapping::KeyFrameCulling()
{
// Check redundant keyframes (only local keyframes)
// A keyframe is considered redundant if the 90% of the MapPoints it sees, are seen
// in at least other 3 keyframes (in the same or finer scale)
vector<KeyFrame*> vpLocalKeyFrames = mpCurrentKeyFrame->GetVectorCovisibleKeyFrames();
for(vector<KeyFrame*>::iterator vit=vpLocalKeyFrames.begin(), vend=vpLocalKeyFrames.end(); vit!=vend; vit++)
{
KeyFrame* pKF = *vit;
if(pKF->mnId==0)
continue;
vector<MapPoint*> vpMapPoints = pKF->GetMapPointMatches();
int nRedundantObservations=0;
int nMPs=0;
for(size_t i=0, iend=vpMapPoints.size(); i<iend; i++)
{
MapPoint* pMP = vpMapPoints[i];
if(pMP)
{
if(!pMP->isBad())
{
nMPs++;
if(pMP->Observations()>3)
{
int scaleLevel = pKF->GetKeyPointUn(i).octave;
map<KeyFrame*, size_t> observations = pMP->GetObservations();
int nObs=0;
for(map<KeyFrame*, size_t>::iterator mit=observations.begin(), mend=observations.end(); mit!=mend; mit++)
{
KeyFrame* pKFi = mit->first;
if(pKFi==pKF)
continue;
int scaleLeveli = pKFi->GetKeyPointUn(mit->second).octave;
if(scaleLeveli<=scaleLevel+1)
{
nObs++;
if(nObs>=3)
break;
}
}
if(nObs>=3)
{
nRedundantObservations++;
}
}
}
}
}
if(nRedundantObservations>0.9*nMPs)
pKF->SetBadFlag();
}
}
