void
DistanceTransformNonEuclid(vector<double>& D,
const vector<unsigned char>& L,
const vector<int>& leadingNbh,
const vector<int>& trailingNbh,
const vector<double>& leadingWgt,
const vector<double>& trailingWgt,
int ndim,
const int* dims) {
int i,j;
int nvoxels=numberOfElements(ndim,dims);
//construct a subscript representation of the neighborhood
//for efficient boundary check
vector<int> vcoordsL;
for(i=0; i<leadingNbh.size(); ++i) {
vector<int> vsub = Ind2SubCentered(leadingNbh[i],ndim,dims);
vcoordsL.insert(vcoordsL.end(),vsub.begin(),vsub.end());
}
vector<int> vcoordsT;
for(i=0; i<leadingNbh.size(); ++i) {
vector<int> vsub = Ind2SubCentered(trailingNbh[i],ndim,dims);
vcoordsT.insert(vcoordsT.end(),vsub.begin(),vsub.end());
}
//first pass - from upper left to lower right
for(i=0; i<nvoxels; ++i) {
double v1=GetData(D,i,(double)0);
double minV=INFINITY;
vector<int> vsub = Ind2Sub(i,ndim,dims);
for(j=0; j<leadingNbh.size(); ++j) {
if(NeighborCheck(vsub.begin(),vcoordsL.begin()+j*ndim,ndim,dims)) {
int k=i+leadingNbh[j];
double v2=D[k]; //trust BoundaryCheck - no array boundary check here
minV=Min(minV,v2+leadingWgt[j]);
}
}
if(v1>minV)
SetData(D,i,minV);
}
//second pass - from lower right to upper left
for(i=nvoxels-1; i>=0; --i) {
double v1=GetData(D,i,(double)0);
double minV=INFINITY;
vector<int> vsub = Ind2Sub(i,ndim,dims);
for(j=0; j<trailingNbh.size(); ++j) {
if(NeighborCheck(vsub.begin(),vcoordsT.begin()+j*ndim,ndim,dims)) {
int k=i+trailingNbh[j];
double v2=D[k]; //trust BoundaryCheck - no array boundary check here
minV=Min(minV,v2+trailingWgt[j]);
}
}
if(v1>minV)
SetData(D,i,minV);
}
}
bool
NeighborCheck(int p,
int offset,
int ndim,
const int* dims) {
vector<int> vsub = Ind2Sub(p, ndim, dims);
vector<int> voff = Ind2SubCentered(offset, ndim, dims);
if(voff.size()>ndim)
return false; //index overflow
for(int i=0; i<ndim; ++i) {
if(vsub[i]+voff[i]<0 || vsub[i]+voff[i]>=dims[i]) {
return false;
}
}
return true;
}
void
LocalMinimum(vector<unsigned char>& M,
const vector<Item>& V,
const vector<unsigned char>& L,
const vector<int>& nbh,
bool strict,
int ndim,
const int* dims)
{
int nvoxels = numberOfElements(ndim,dims);
if(M.size()<nvoxels || V.size()<nvoxels || L.size()<nvoxels)
{
//mexPrintf("An input image does not contain enough data.\n");
return;
}
int i;
//construct a subscript representation of the neighborhood
//for efficient boundary check
vector<int> vcoords;
for(i=0; i<nbh.size(); ++i)
{
vector<int> vsub = Ind2SubCentered(nbh[i],ndim,dims);
vcoords.insert(vcoords.end(),vsub.begin(),vsub.end());
}
for(i=0; i<nvoxels; ++i)
{
unsigned char lb=L[i];
if(!lb)
continue; //not inside ROI
bool bLM=true;
bool b0;
Item origV=V[i];
vector<int> vsub = Ind2Sub(i,ndim,dims);
for(int j=0; j<nbh.size(); ++j)
{
if(NeighborCheck(vsub.begin(),vcoords.begin()+j*ndim,ndim,dims))
{
int k=i+nbh[j];
if(L[k])
{
bool b;
Item v2=V[k];
if(strict) {// strictly maximum
if(v2<=origV)
{
bLM=false;
break;
}
}
else
{
if(v2<origV)
{
bLM=false;
break;
}
}
}
}
}
if(bLM)
{
SetData(M,i,(unsigned char) 1);
}
else
{
SetData(M,i,(unsigned char) 0);
}
}
}