diff --git a/app/GenericRegionMerging.cxx b/app/GenericRegionMerging.cxx
index 20799af23c2086ed93c0a6e2b4cc6c8d6b1c4f9a..90f0065f5707a5431f6805431b18760ee6efb385 100644
--- a/app/GenericRegionMerging.cxx
+++ b/app/GenericRegionMerging.cxx
@@ -165,7 +165,7 @@ namespace otb
 					// Set output image projection, origin and spacing for labelImage
 					labelImage->SetProjectionRef(image->GetProjectionRef());
 					labelImage->SetOrigin(image->GetOrigin());
-					labelImage->SetSpacing(image->GetSpacing());
+					labelImage->SetSignedSpacing(image->GetSignedSpacing());
 					SetParameterOutputImage<LabelImageType>("out", labelImage);
 				}
 		};