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vcglib/vcg/complex/trimesh/autoalign_4pcs.h

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#ifndef _4PCS_
#define _4PCS_
/****************************************************************************
* VCGLib o o *
* Visual and Computer Graphics Library o o *
* _ O _ *
* Copyright(C) 2004 \/)\/ *
* Visual Computing Lab /\/| *
* ISTI - Italian National Research Council | *
* \ *
* All rights reserved. *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
* This program 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 General Public License (http://www.gnu.org/licenses/gpl.txt) *
* for more details. *
* *
****************************************************************************/
/**
implementation of the 4PCS method from the paper:
"4-Points Congruent Sets for Robust Pairwise Surface Registration"
D.Aiger, N.Mitra D.Cohen-Or, SIGGRAPH 2008
ps: the name of the variables are out of vcg standard but like the one
used in the paper pseudocode.
*/
#include <vcg/space/point3.h>
#include <vcg/space/point4.h>
#include <vcg/space/line3.h>
#include <vcg/space/plane3.h>
#include <vcg/math/base.h>
#include <vcg/math/point_matching.h>
#include <vcg/math/matrix44.h>
#include <vcg/space/index/grid_static_ptr.h>
#include <vcg/complex/trimesh/closest.h>
#include <vcg/complex/trimesh/update/bounding.h>
#include <vcg/simplex/vertex/base.h>
#include <vcg/simplex/face/base.h>
#include <vcg/complex/trimesh/base.h>
#include <vcg/complex/trimesh/stat.h>
#include <wrap/io_trimesh/export_ply.h>
// note: temporary (callback.h should be moved inside vcg)
typedef bool AACb( const int pos,const char * str );
namespace vcg{
namespace tri{
template <class MeshType>
class FourPCS {
public:
/* mesh only for using spatial indexing functions (to remove) */
class PEdge; // dummy prototype never used
class PFace;
class PVertex : public vcg::VertexSimp2< PVertex, PEdge, PFace,vcg::vertex::BitFlags,vcg::vertex::Coord3f ,vcg::vertex::Mark>{};
/*same as for the vertes */
class PFace : public vcg::FaceSimp2< PVertex, PEdge, PFace> {};
/*the mesh is a container of vertices and a container of faces */
class PMesh : public vcg::tri::TriMesh< std::vector<PVertex>, std::vector<PFace> > {};
typedef typename MeshType::ScalarType ScalarType;
typedef typename MeshType::CoordType CoordType;
typedef typename MeshType::VertexIterator VertexIterator;
typedef typename MeshType::VertexType VertexType;
typedef vcg::Point4< vcg::Point3<ScalarType> > FourPoints;
typedef vcg::GridStaticPtr<typename PMesh::VertexType, ScalarType > GridType;
/* class for Parameters */
struct Parameters{
ScalarType delta;
int feetsize; // how many points in the neighborhood of each of the 4 points
ScalarType f; // overlapping estimation
int scoreFeet, // how many of the feetsize points must match (max feetsize*4) to try an early interrupt
scoreAln; // how good must be the alignement to end the process successfully
void Default(){
delta = 0.5;
feetsize = 25;
f = 0.5;
scoreFeet = 50;
scoreAln = 200;
}
};
Parameters prs; /// parameters
public:
void Init(MeshType &_P,MeshType &_Q);
bool Align( int L, vcg::Matrix44f & result, AACb * cb = NULL ); // main function
private:
struct Couple: public std::pair<int,int>{
Couple(const int & i, const int & j, float d):std::pair<int,int>(i,j),dist(d){}
Couple(float d):std::pair<int,int>(0,0),dist(d){}
float dist;
const bool operator < (const Couple & o) const {return dist < o.dist;}
int & operator[](const int &i){return (i==0)? first : second;}
};
/* returns the closest point between to segments x1-x2 and x3-x4. */
void IntersectionLineLine(const CoordType & x1,const CoordType & x2,const CoordType & x3,const CoordType & x4, CoordType&x)
{
CoordType a = x2-x1, b = x4-x3, c = x3-x1;
x = x1 + a * ((c^b).dot(a^b)) / (a^b).SquaredNorm();
}
struct CandiType{
CandiType(){};
CandiType(FourPoints _p,vcg::Matrix44<ScalarType>_T):p(_p),T(_T){}
FourPoints p;
vcg::Matrix44<ScalarType> T;
ScalarType err;
int score;
int base; // debug: for which base
const bool & operator <(const CandiType & o) const {return score > o.score;}
};
MeshType *P, // mesh from which the coplanar base is selected
*Q; // mesh where to find the correspondences
std::vector<int> mapsub; // subset of index to the vertices in Q
PMesh Invr; // invariants
std::vector< CandiType > U;
CandiType winner;
int iwinner; // winner == U[iwinner]
FourPoints B; // coplanar base
std::vector<FourPoints> bases; // used bases
ScalarType side; // side
std::vector<VertexType*> ExtB[4]; // selection of vertices "close" to the four point
std::vector<VertexType*> subsetP; // random selection on P
ScalarType radius;
ScalarType Bangle;
std::vector<Couple > R1/*,R2*/;
ScalarType r1,r2;
// class for the point 'ei'
struct EPoint{
EPoint(vcg::Point3<ScalarType> _p, int _i):pos(_p),pi(_i){}
vcg::Point3<ScalarType> pos;
int pi; //index to R[1|2]
void GetBBox(vcg::Box3<ScalarType> & b){b.Add(pos);}
};
GridType *ugrid; // griglia
vcg::GridStaticPtr<typename MeshType::VertexType, ScalarType > ugridQ;
vcg::GridStaticPtr<typename MeshType::VertexType, ScalarType > ugridP;
//FILE * f;
//private:
bool SelectCoplanarBase(); // on P
bool FindCongruent() ; // of base B, on Q, with approximation delta
//private:
void ComputeR1R2(ScalarType d1,ScalarType d2);
bool IsTransfCongruent(FourPoints fp,vcg::Matrix44<ScalarType> & mat, float & trerr);
int EvaluateSample(CandiType & fp, CoordType & tp, CoordType & np, const float & angle);
void EvaluateAlignment(CandiType & fp);
void TestAlignment(CandiType & fp);
/* debug tools */
public:
std::vector<vcg::Matrix44f> allTr;// tutte le trasformazioni provate
FILE * db;
char namemesh1[255],namemesh2[255];
int n_base;
void InitDebug(const char * name1, const char * name2){
db = fopen("debugPCS.txt","w");
sprintf(&namemesh1[0],"%s",name1);
sprintf(&namemesh2[0],"%s",name2);
n_base = 0;
}
void FinishDebug(){
fclose(db);
}
//void SaveALN(char * name,vcg::Matrix44f mat ){
// FILE * o = fopen(name,"w");
// fprintf(o,"2\n%s\n#\n",namemesh1);
// for(int i = 0 ; i < 4; ++i)
// fprintf(o,"%f %f %f %f\n",mat[i][0],mat[i][1],mat[i][2],mat[i][3]);
// fprintf(o,"%s\n#\n",namemesh2);
// fprintf(o,"1.0 0.0 0.0 0.0 \n");
// fprintf(o,"0.0 1.0 0.0 0.0 \n");
// fprintf(o,"0.0 0.0 1.0 0.0 \n");
// fprintf(o,"0.0 0.0 0.0 1.0 \n");
// fclose(o);
//}
};
template <class MeshType>
void
FourPCS<MeshType>:: Init(MeshType &_P,MeshType &_Q){
P = &_P;Q=&_Q;
ugridQ.Set(Q->vert.begin(),Q->vert.end());
ugridP.Set(P->vert.begin(),P->vert.end());
int vi;
// float areaP = vcg::tri::Stat<MeshType>::ComputeMeshArea(*P);
// float areaQ = vcg::tri::Stat<MeshType>::ComputeMeshArea(*Q);
float ratio = 800 / (float) Q->vert.size();
for(vi = 0; vi < Q->vert.size(); ++vi)
if(rand()/(float) RAND_MAX < ratio)
mapsub.push_back(vi);
for(vi = 0; vi < P->vert.size(); ++vi)
if(rand()/(float) RAND_MAX < ratio)
subsetP.push_back(&P->vert[vi]);
// estimate neigh distance
float avD = 0.0,dist;
for(int i = 0 ; i < 100; ++i){
int ri = rand()/(float) RAND_MAX * Q->vert.size() -1;
std::vector< CoordType > samples,d_samples;
std::vector<ScalarType > dists;
std::vector<VertexType* > ress;
vcg::tri::GetKClosestVertex<
MeshType,
vcg::GridStaticPtr<typename MeshType::VertexType, ScalarType>,
std::vector<VertexType*>,
std::vector<ScalarType>,
std::vector< CoordType > >(*Q,ugridQ,2,Q->vert[ri].cP(),Q->bbox.Diag(), ress,dists, samples);
assert(ress.size() == 2);
avD+=dists[1];
}
avD /=100; // average vertex-vertex distance
avD /= sqrt(ratio); // take into account the ratio
prs.delta = avD * prs.delta;
side = P->bbox.Dim()[P->bbox.MaxDim()]*prs.f; //rough implementation
}
template <class MeshType>
bool
FourPCS<MeshType>::SelectCoplanarBase(){
vcg::tri::UpdateBounding<MeshType>::Box(*P);
// choose the inter point distance
ScalarType dtol = side*0.1; //rough implementation
//choose the first two points
int i = 0,ch;
// first point random
ch = (rand()/(float)RAND_MAX)*(P->vert.size()-2);
B[0] = P->vert[ch].P();
//printf("B[0] %d\n",ch);
// second a point at distance d+-dtol
for(i = 0; i < P->vert.size(); ++i){
ScalarType dd = (P->vert[i].P() - B[0]).Norm();
if( ( dd < side + dtol) && (dd > side - dtol)){
B[1] = P->vert[i].P();
//printf("B[1] %d\n",i);
break;
}
}
if(i == P->vert.size())
return false;
// third point at distance d from B[1] and forming a right angle
int best = -1; ScalarType bestv=std::numeric_limits<float>::max();
for(i = 0; i < P->vert.size(); ++i){
int id = rand()/(float)RAND_MAX * (P->vert.size()-1);
ScalarType dd = (P->vert[id].P() - B[1]).Norm();
if( ( dd < side + dtol) && (dd > side - dtol)){
ScalarType angle = fabs( ( P->vert[id].P()-B[1]).normalized().dot((B[1]-B[0]).normalized()));
if( angle < bestv){
bestv = angle;
best = id;
}
}
}
if(best == -1)
return false;
B[2] = P->vert[best].P();
//printf("B[2] %d\n",best);
CoordType n = ((B[0]-B[1]).normalized() ^ (B[2]-B[1]).normalized()).normalized();
CoordType B4 = B[1] + (B[0]-B[1]) + (B[2]-B[1]);
VertexType * v =0;
ScalarType radius = dtol*4.0;
std::vector<typename MeshType::VertexType*> closests;
std::vector<ScalarType> distances;
std::vector<CoordType> points;
vcg::tri::GetInSphereVertex<
MeshType,
vcg::GridStaticPtr<typename MeshType::VertexType, ScalarType >,
std::vector<typename MeshType::VertexType*>,
std::vector<ScalarType>,
std::vector<CoordType>
>(*P,ugridP,B4,radius,closests,distances,points);
if(closests.empty())
return false;
best = -1; bestv=std::numeric_limits<float>::max();
for(i = 0; i <closests.size(); ++i){
ScalarType angle = fabs((closests[i]->P() - B[1]).normalized().dot(n));
if( angle < bestv){
bestv = angle;
best = i;
}
}
B[3] = closests[best]->P();
//printf("B[3] %d\n", (typename MeshType::VertexType*)closests[best] - &(*P->vert.begin()));
// compute r1 and r2
CoordType x;
std::swap(B[1],B[2]);
IntersectionLineLine(B[0],B[1],B[2],B[3],x);
r1 = (x - B[0]).dot(B[1]-B[0]) / (B[1]-B[0]).SquaredNorm();
r2 = (x - B[2]).dot(B[3]-B[2]) / (B[3]-B[2]).SquaredNorm();
if( ((B[0]+(B[1]-B[0])*r1)-(B[2]+(B[3]-B[2])*r2)).Norm() > prs.delta )
return false;
radius =side*0.5;
std::vector< CoordType > samples,d_samples;
std::vector<ScalarType > dists;
for(int i = 0 ; i< 4; ++i){
vcg::tri::GetKClosestVertex<
MeshType,
vcg::GridStaticPtr<typename MeshType::VertexType, ScalarType >,
std::vector<VertexType*>,
std::vector<ScalarType>,
std::vector< CoordType > >(*P,ugridP, prs.feetsize ,B[i],radius, ExtB[i],dists, samples);
}
//for(int i = 0 ; i< 4; ++i)
// printf("%d ",ExtB[i].size());
// printf("\n");
return true;
}
template <class MeshType>
bool
FourPCS<MeshType>::IsTransfCongruent(FourPoints fp,vcg::Matrix44<ScalarType> & mat, float & trerr){
std::vector<vcg::Point3<ScalarType> > fix;
std::vector<vcg::Point3<ScalarType> > mov;
for(int i = 0 ; i < 4; ++i) mov.push_back(B[i]);
for(int i = 0 ; i < 4; ++i) fix.push_back(fp[i]);
vcg::Point3<ScalarType> n,p;
n = (( B[1]-B[0]).normalized() ^ ( B[2]- B[0]).normalized())*( B[1]- B[0]).Norm();
p = B[0] + n;
mov.push_back(p);
n = (( fp[1]-fp[0]).normalized() ^ (fp[2]- fp[0]).normalized())*( fp[1]- fp[0]).Norm();
p = fp[0] + n;
fix.push_back(p);
vcg::PointMatching<ScalarType>::ComputeRigidMatchMatrix(mat,fix,mov);
ScalarType err = 0.0;
for(int i = 0; i < 4; ++i) err+= (mat * mov[i] - fix[i]).SquaredNorm();
trerr = vcg::math::Sqrt(err);
return err < prs.delta* prs.delta*4.0;
}
template <class MeshType>
void
FourPCS<MeshType>::ComputeR1R2(ScalarType d1,ScalarType d2){
int vi,vj;
R1.clear();
//R2.clear();
int start = clock();
for(vi = 0; vi < mapsub.size(); ++vi) for(vj = vi; vj < mapsub.size(); ++vj){
ScalarType d = ((Q->vert[mapsub[vi]]).P()-(Q->vert[mapsub[vj]]).P()).Norm();
if( (d < d1+ side*0.5) && (d > d1-side*0.5))
{
R1.push_back(Couple(mapsub[vi],mapsub[vj],d ));
R1.push_back(Couple(mapsub[vj],mapsub[vi],d));
}
}
//for( vi = 0; vi < mapsub.size(); ++ vi ) for( vj = vi ; vj < mapsub.size(); ++ vj ){
// ScalarType d = ((Q->vert[mapsub[vi]]).P()-(Q->vert[mapsub[vj]]).P()).Norm();
// if( (d < d2+side*0.5) && (d > d2-side*0.5))
// {
// R2.push_back(Couple(mapsub[vi],mapsub[vj],d));
// R2.push_back(Couple(mapsub[vj],mapsub[vi],d));
// }
//}
std::sort(R1.begin(),R1.end());
// std::sort(R2.begin(),R2.end());
}
template <class MeshType>
bool
FourPCS<MeshType>::FindCongruent() { // of base B, on Q, with approximation delta
bool done = false;
std::vector<EPoint> R2inv;
int n_closests = 0, n_congr = 0;
int ac =0 ,acf = 0,tr = 0,trf =0;
ScalarType d1,d2;
d1 = (B[1]-B[0]).Norm();
d2 = (B[3]-B[2]).Norm();
int start = clock();
//int vi,vj;
typename PMesh::VertexIterator vii;
typename std::vector<Couple>::iterator bR1,eR1,bR2,eR2,ite,cite;
bR1 = std::lower_bound<typename std::vector<Couple>::iterator,Couple>(R1.begin(),R1.end(),Couple(d1-prs.delta*2.0));
eR1 = std::lower_bound<typename std::vector<Couple>::iterator,Couple>(R1.begin(),R1.end(),Couple(d1+prs.delta*2.0));
bR2 = std::lower_bound<typename std::vector<Couple>::iterator,Couple>(R1.begin(),R1.end(),Couple(d2-prs.delta*2.0));
eR2 = std::lower_bound<typename std::vector<Couple>::iterator,Couple>(R1.begin(),R1.end(),Couple(d2+prs.delta*2.0));
// in [bR1,eR1) there are all the pairs ad a distance d1 +- prs.delta
// in [bR1,eR1) there are all the pairs ad a distance d2 +- prs.delta
if(bR1 == R1.end()) return false;// if there are no such pairs return
if(bR2 == R1.end()) return false; // if there are no such pairs return
// put [bR1,eR1) in a mesh to have the search operator for free (lazy me)
Invr.Clear();
int i = &(*bR1)-&(*R1.begin());
for(ite = bR1; ite != eR1;++ite){
vii = vcg::tri::Allocator<PMesh>::AddVertices(Invr,1);
(*vii).P() = Q->vert[R1[i][0]].P() + (Q->vert[R1[i][1]].P()-Q->vert[R1[i][0]].P()) * r1;
++i;
}
if(Invr.vert.empty() ) return false;
// index remaps a vertex of Invr to its corresponding point in R1
typename PMesh::template PerVertexAttributeHandle<int> id = vcg::tri::Allocator<PMesh>::template AddPerVertexAttribute<int>(Invr,std::string("index"));
i = &(*bR1)-&(*R1.begin());
for(vii = Invr.vert.begin(); vii != Invr.vert.end();++vii,++i) id[vii] = i;
vcg::tri::UpdateBounding<PMesh>::Box(Invr);
// printf("Invr size %d\n",Invr.vn);
ugrid = new GridType();
ugrid->Set(Invr.vert.begin(),Invr.vert.end());
i = &(*bR2)-&(*R1.begin());
// R2inv contains all the points generated by the couples in R2 (with the reference to remap into R2)
for(ite = bR2; ite != eR2;++ite){
R2inv.push_back( EPoint( Q->vert[R1[i][0]].P() + (Q->vert[R1[i][1]].P()-Q->vert[R1[i][0]].P()) * r2,i));
++i;
}
n_closests = 0; n_congr = 0; ac =0 ; acf = 0; tr = 0; trf = 0;
// fprintf(db,"R2Inv.size = %d \n",R2inv.size());
for(uint i = 0 ; i < R2inv.size() ; ++i){
std::vector<typename PMesh::VertexType*> closests;
std::vector<ScalarType> distances;
std::vector<CoordType> points;
// for each point in R2inv get all the points in R1 closer than prs.delta
vcg::Matrix44<ScalarType> mat;
vcg::Box3f bb;
bb.Add(R2inv[i].pos+vcg::Point3f(prs.delta * 0.1,prs.delta * 0.1 , prs.delta * 0.1 ));
bb.Add(R2inv[i].pos-vcg::Point3f(prs.delta * 0.1,prs.delta* 0.1 , prs.delta* 0.1));
vcg::tri::GetInBoxVertex<PMesh,GridType,std::vector<typename PMesh::VertexType*> >
(Invr,*ugrid,bb,closests);
n_closests+=closests.size();
for(uint ip = 0; ip < closests.size(); ++ip){
FourPoints p;
p[0] = Q->vert[R1[id[closests[ip]]][0]].P();
p[1] = Q->vert[R1[id[closests[ip]]][1]].P();
p[2] = Q->vert[R1[ R2inv[i].pi][0]].P();
p[3] = Q->vert[R1[ R2inv[i].pi][1]].P();
float trerr;
n_base++;
if(!IsTransfCongruent(p,mat,trerr)) {
trf++;
//char name[255];
//sprintf(name,"faileTR_%d_%f.aln",n_base,trerr);
//fprintf(db,"TransCongruent %s\n", name);
//SaveALN(name, mat);
}
else{
tr++;
n_congr++;
U.push_back(CandiType(p,mat));
EvaluateAlignment(U.back());
U.back().base = bases.size()-1;
if( U.back().score > prs.scoreFeet){
TestAlignment(U.back());
if(U.back().score > prs.scoreAln)
{
done = true; break;
}
}
//char name[255];
//sprintf(name,"passed_score_%5d_%d.aln",U.back().score,n_base);
//fprintf(db,"OK TransCongruent %s, score: %d \n", name,U.back().score);
//SaveALN(name, mat);
}
}
}
delete ugrid;
vcg::tri::Allocator<PMesh>::DeletePerVertexAttribute(Invr,id);
printf("n_closests %5d = (An %5d ) + ( Tr %5d ) + (OK) %5d\n",n_closests,acf,trf,n_congr);
return done;
// printf("done n_closests %d congr %d in %f s\n ",n_closests,n_congr,(clock()-start)/(float)CLOCKS_PER_SEC);
// printf("angle:%d %d, trasf %d %d\n",ac,acf,tr,trf);
}
template <class MeshType>
int FourPCS<MeshType>::EvaluateSample(CandiType & fp, CoordType & tp, CoordType & np, const float & angle){
VertexType* v;
ScalarType dist ;
radius = prs.delta;
tp = fp.T * tp;
vcg::Point4<ScalarType> np4;
np4 = fp.T * vcg::Point4<ScalarType>(np[0],np[1],np[2],0.0);
np[0] = np4[0]; np[1] = np4[1]; np[2] = np4[2];
v = 0;
//v = vcg::tri::GetClosestVertex<
// MeshType,
// vcg::GridStaticPtr<typename MeshType::VertexType, ScalarType >
// >(*Q,ugridQ,tp,radius, dist );
typename MeshType::VertexType vq;
vq.P() = tp;
vq.N() = np;
v = vcg::tri::GetClosestVertexNormal<
MeshType,
vcg::GridStaticPtr<typename MeshType::VertexType, ScalarType >
>(*Q,ugridQ,vq,radius, dist );
if(v!=0)
if( v->N().dot(np) -angle >0) return 1; else return -1;
}
template <class MeshType>
void
FourPCS<MeshType>::EvaluateAlignment(CandiType & fp){
int n_delta_close = 0;
for(int i = 0 ; i< 4; ++i) {
for(uint j = 0; j < ExtB[i].size();++j){
CoordType np = ExtB[i][j]->cN();;
CoordType tp = ExtB[i][j]->P();
n_delta_close+=EvaluateSample(fp,tp,np,0.9);
}
}
fp.score = n_delta_close;
}
template <class MeshType>
void
FourPCS<MeshType>::TestAlignment(CandiType & fp){
radius = prs.delta;
int n_delta_close = 0;
for(uint j = 0; j < subsetP.size();++j){
CoordType np = subsetP[j]->N();
CoordType tp = subsetP[j]->P();
n_delta_close+=EvaluateSample(fp,tp,np,0.6);
}
fp.score = n_delta_close;
}
template <class MeshType>
bool
FourPCS<MeshType>:: Align( int L, vcg::Matrix44f & result, AACb * cb ){ // main loop
int bestv = 0;
bool found;
int n_tries = 0;
U.clear();
if(L==0)
{
L = (log(1.0-0.9999) / log(1.0-pow((float)prs.f,3.f)))+1;
printf("using %d bases\n",L);
}
ComputeR1R2(side*1.4,side*1.4);
for(int t = 0; t < L; ++t ){
do{
n_tries = 0;
do{
n_tries++;
found = SelectCoplanarBase();
}
while(!found && (n_tries <50));
if(!found) {
prs.f*=0.98;
side = P->bbox.Dim()[P->bbox.MaxDim()]*prs.f; //rough implementation
ComputeR1R2(side*1.4,side*1.4);
}
} while (!found && (prs.f >0.1));
if(prs.f <0.1) {
printf("FAILED");
return false;
}
bases.push_back(B);
if(cb) cb(t*100/L,"trying bases");
if(FindCongruent())
break;
}
if(U.empty()) return false;
std::sort(U.begin(),U.end());
bestv = -std::numeric_limits<float>::max();
iwinner = 0;
for(int i = 0 ; i < U.size() ;++i)
{
TestAlignment(U[i]);
if(U[i].score > bestv){
bestv = U[i].score;
iwinner = i;
}
}
printf("Best score: %d \n", bestv);
winner = U[iwinner];
result = winner.T;
// deallocations
Invr.Clear();
return true;
}
} // namespace tri
} // namespace vcg
#endif
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