Execution fails when image has no objects

[ftavella]

When there are no objects to segment, the code fails here, on filterLabels.m.

We need to implement a mechanism to handle images without objects.

[ftavella]

Possible solution.
On filterLabels.m:

  % Sort region properties by Label
  filteredRegionProperties = struct2table(filteredRegionProperties);
  columnOrder = {'Label', 'Area', 'Centroid', 'Circularity', 'Eccentricity'};
  if size(filteredRegionProperties, 1) > 0
      filteredRegionProperties = sortrows(filteredRegionProperties, 'Label');
      filteredRegionProperties = table2struct(filteredRegionProperties);
      % Reorder fields
      filteredRegionProperties = orderfields(filteredRegionProperties, columnOrder);
  else
      filteredRegionProperties = struct(columnOrder{1}, {}, columnOrder{2}, {}, ...
                                        columnOrder{3}, {}, columnOrder{4}, {}, columnOrder{5}, {});
  end