+protected:
+ virtual std::string src_parameters () const = 0;
+ virtual std::string src_name () const = 0;
+ virtual void* sink_parameters () const = 0;
+ virtual std::string sink_name () const = 0;
+
+ AVFilterGraph* _graph;
+ /** true if this graph has no filters in, so it just copies stuff straight through */
+ bool _copy;