int n = input->GetLargestPossibleRegion().GetNumberOfPixels();
std::vector<int> should_keep(values.size());;
std::fill(should_keep.begin(), should_keep.end(), 0);
int n = input->GetLargestPossibleRegion().GetNumberOfPixels();
std::vector<int> should_keep(values.size());;
std::fill(should_keep.begin(), should_keep.end(), 0);