- o -

• Operation : Gtkmm2ext::Bindings , RangeMarkerBarDrag , SelectionDrag , TrimDrag
• Operator : ARDOUR::Transform::Operation
• Orientation : ArdourCanvas::Box , ArdourCanvas::LineSet , ArdourCanvas::Meter , ArdourWidgets::FaderWidget , ArdourWidgets::FastMeter , ArdourWidgets::Frame , InputPortMonitor
• OSCDebugMode : ArdourSurface::OSC
• OSCTempMode : ArdourSurface::OSC
• OverlapPitchResolution : Evoral::Sequence< Time >