The AREATYPEENUM enumeration provides information about the shape of area to capture.
typedef enum tagAREATYPEENUM{CAPTURE_AREA_TRIANGLE=1,CAPTURE_AREA_RECT,CAPTURE_AREA_ROUNDRECT,CAPTURE_AREA_ELLIPSE,CAPTURE_AREA_POLYGON,CAPTURE_AREA_FREEHAND} AREATYPEENUM;
Triangle.
Rectangle.
Rounded Rectangle.
Ellipse.
Polygon (each click defines point).
Freehand (click and drag).