batchDenoise check for empty image

matlab/+DenoiseCache/batchDenoise.m

@@ -52,6 +52,9 @@ for step=1:num_steps
         end
     end
     % write out the chunk      
+    if isempty(im)
+        continue
+    end
     if 1==t0
         prepareH5(targetFile,im);        
     end

matlab/+Ensemble/setCellEfficiency.m

@@ -15,7 +15,7 @@ else
     se=strel('disk',3);
 end
 imBG=imerode(im,se);
-if isfield(segParams,'sensitivity')
+if isfield(segParams,'sensitivity') && segParams.sensitivity<1
     sensitivity=segParams.sensitivity;
 else
     sensitivity=0.5;