diff --git a/LandscapeStratificationMetric.py b/LandscapeStratificationMetric.py
index 60b50ada167ce14659a9db5618dd1d922b989ca7..8d4b25f97fbf22a2e3ee0decac77ead694f2d5a2 100644
--- a/LandscapeStratificationMetric.py
+++ b/LandscapeStratificationMetric.py
@@ -203,14 +203,6 @@ class LandscapeStratification(QgsProcessingAlgorithm):
             )
         )
 
-        self.addParameter(
-            QgsProcessingParameterString(
-                self.PREFIX,
-                self.tr('Output files prefix'),
-                ''
-            )
-        )
- 
         self.addParameter(
             QgsProcessingParameterNumber(
                 self.CBEGIN,
@@ -254,9 +246,7 @@ class LandscapeStratification(QgsProcessingAlgorithm):
 
         output_folder = os.path.dirname(output_raster)
 
-        prefix = parameters['PREFIX'] if parameters['PREFIX'] != None else ''
-        if len(prefix)>0 and prefix[-1] != '_':
-            prefix+='_'
+        prefix = os.path.splitext(os.path.basename(output_raster))[0] + '_'
         begin_date = parameters['BEGDATE'] if parameters['BEGDATE'] != None else 20000101
         end_date = parameters['ENDDATE'] if parameters['ENDDATE'] != None else int(datetime.date.today().strftime("%Y%m%d"))
 
@@ -318,8 +308,10 @@ class LandscapeStratification(QgsProcessingAlgorithm):
         processing.run('otb:ManageNoData', ND_app_parameters, context=context, feedback=feedback)
         setNoDataValue(LS_Strat, ndv)
 
+        '''
         nm = os.path.basename(os.path.splitext(LS_Strat)[0])
         context.addLayerToLoadOnCompletion(LS_Strat,
                                            QgsProcessingContext.LayerDetails(name=nm, project=context.project()))
-        
+        '''
+
         return {'OUT':LS_Strat}
diff --git a/landtools.py b/landtools.py
index aa38e0a88b04f6c35b4f475d36374053498d27c5..4e038af7df294fbc1ad6238486daf871910ca247 100644
--- a/landtools.py
+++ b/landtools.py
@@ -40,7 +40,7 @@ def get_period_intervals(date_file, md=[1, 1], duration=365):
     return periods
 
 def get_mean_expression(periods):
-    l = periods[0][1] - periods[0][0] + 1
+    l = periods[0][1] - periods[0][0]
     expr = []
     for i in range(1, l + 1):
         s = [p[0] + i for p in periods]