bool is_comparable( const Descriptor & desc1, const Descriptor & desc2){
return !desc1.empty() && !desc2.empty()
&& desc1.size_a() == desc2.size_a()
&& desc1.size_z() == desc2.size_z()
&& desc1.size_r() == desc2.size_r()
&& desc1.page() == desc2.page();
}
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());
}