Update help

tools/2d_auto_threshold/auto_threshold.xml

@@ -72,7 +72,7 @@
                 <param name="block_size" type="integer" value="5" label="Odd size of pixel neighborhood for determining the threshold" />
             </when>
         </conditional>
-        <param name="invert_output" type="boolean" checked="false" truevalue="True" falsevalue="False" label="Invert output labels" help="Pixels with values below and above the threshold are usually labeled with the values 0 and 255, or with 255 and 0 if this option is activated." />
+        <param name="invert_output" type="boolean" checked="false" truevalue="True" falsevalue="False" label="Invert output labels" help="Pixels are usually assigned the label 0 if the pixel value is below (or equal to) the threshold, and 255 if it is above the threshold. If this option is activated, pixels are assigned the label 255 if the pixel value is below (or equal to) the threshold, and 0 if it is above the threshold." />
     </inputs>
     <outputs>
        <data format="tiff" name="output" from_work_dir="out.tif" />