--- a/dmri.xml	Thu Nov 30 11:02:43 2017 -0500
+++ b/dmri.xml	Thu Nov 30 11:09:00 2017 -0500
@@ -7,7 +7,9 @@
 python '$__tool_directory__/dmri.py'
 --drmi_dataset_type '$drmi_dataset_type_cond.drmi_dataset_type'
 --drmi_dataset $drmi_dataset
---output_png '$output_png'
+#if str($drmi_dataset) == "stanford_hardi":
+    --output_png '$output_png'
+#end if
 --output_nifti1 '$output_nifti1'
 --output_nifti1_extra_files '$output_nifti1.files_path'
 &>/dev/null
@@ -27,8 +29,10 @@
         </param>
     </inputs>
     <outputs>
-        <data name="output_png" format="png" label="${tool.name}: middle axial slice without (left) and with (right) diffusion weighting" />
-        <data name="output_nifti1" format="nifti1" label="${tool.name}: ($drmi_dataset_type_cond['drmi_dataset_type']) Nifti1 image" />
+        <data name="output_png" format="png" label="${tool.name}: middle axial slice without (left) and with (right) diffusion weighting">
+            <filter>drmi_dataset == 'stanford_hardi'</filter>
+        </data>
+        <data name="output_nifti1" format="nifti1" label="dRMI dataset $drmi_dataset: ($drmi_dataset_type_cond['drmi_dataset_type']) Nifti1 image" />
     </outputs>
     <tests>
         <test>