constructor ( delta : int = 5 , minArea : int = 60 , maxArea : int = 14400 , maxVariation : number = 0.25 , minDiversity : number = 0.2 , maxEvolution : int = 200 , areaThreshold : number = 1.01 , minMargin : number = 0.003 , edgeBlurSize : int = 5 )