== Preprocessing Modules ==
They are Are filters that modify the previous traces from a given trace source (that can be another Preprocessing Module or the Trace Manager (Channel is supported aswell but only through scripting). It means that multiple modules can be used one after the other. You may want and works as a new trace source to observe the changes in auto-generated script code next module in the "Analysis script" editor widgetchain (called trace observer).
=== Sum of Difference ===