float difference(const Descriptor & desc1, const Descriptor & desc2, Descriptor& desc, float (*diff) (float, float) ){
size_t idx = 0;
float mindiff = inf;
size_t height = desc1.height();
size_t width = desc1.width();
float sum;
for( size_t k = 0; k < desc1.page(); ++k)
{ // k: page # of flipped/rotated descriptors
sum = 0.0f;
for( size_t i = 0; i < height; ++i){ //i, iterates all zenith and azimuth angle bins
for( size_t j = 0; j < width; ++j) //j iterates all radius bins
sum += diff( desc1(i, j, 0), desc2(i,j, k));
}
if( mindiff > sum){
idx = k;
mindiff = sum;
}
}
desc.clear();
Matrixf *pm = new Matrixf( *desc2.getPage( idx ) );
pm->clone();
*pm -= *desc1.getPage(0);
// pm->getAbsoluteValue();
desc.m_vHistPtr.push_back( pm );
desc.m_na = desc1.size_a();
desc.m_nz = desc1.size_z();
desc.m_nr = desc1.size_r();
return mindiff / (desc1.sumWeight() + desc2.sumWeight());
}
float distance(const Descriptor &desc1, const Descriptor &desc2, float (*diff) (float, float) ){
// assuming they are comparable
// float mindiff = inf;
size_t height = desc1.height();
size_t width = desc1.width();
vector<float> sum( desc1.page(), 0.0f);
for( size_t k = 0; k < desc1.page(); ++k)
{ // k: page # of flipped/rotated descriptors
for( size_t i = 0; i < height; ++i){ //i, iterates all zenith and azimuth angle bins
for( size_t j = 0; j < width; ++j) //j iterates all radius bins
sum[k] += diff( desc1(i, j, 0), desc2(i,j, k));
}
// mindiff = min( sum[k], mindiff);
}
return *std::min_element(sum.begin(), sum.end()) /( desc1.sumWeight()+desc2.sumWeight());
}
float distance2( const Descriptor & desc1, const Descriptor & desc2, float (*diff) (float, float) ){
if( is_comparable2( desc1, desc2))
return -1.0f;
// check comparability before calling this function;
size_t ns = min( desc1.width(), desc2.width());
size_t nl = max( desc1.width(), desc2.width());
const Descriptor& desc_longer = desc1.width() > desc2.width() ? desc1 : desc2;
const Descriptor& desc_shorter = desc1.width() > desc2.width() ? desc2 : desc1;
vector<float> sum( desc1.page(), 0.0f);
// float mindiff = inf;
size_t height = desc1.height();
for( size_t k = 0; k < desc1.page(); ++k)
{ // k: page # of rotated descriptors
for( size_t i = 0; i < height; ++i){ //i, iterates all zenith and azimuth angle bins
size_t j = 0;
for( ; j < ns; ++j) //j iterates all radius bins
sum[k] += diff( desc_longer(i, j, 0), desc_shorter(i,j, k));
for( ; j < nl; ++j)
sum[k] += diff( desc_longer(i, j, 0 ), 0);
}
// mindiff = min( sum[k], mindiff);
}
return *std::min_element(sum.begin(), sum.end()) / (desc1.sumWeight() + desc2.sumWeight() );
}