2015-07-02 11:14:38 -0500 asked a question Opencv 3 - python detectmultiscale; too many values to upack I'm trying to get access to either numDetections or rejectLevels and levelWeights so that I can judge confidence levels for each object detected by the cascade classifier. When I try: faces, num_detections = faceCascade.detectMultiScale( gray, scale_factor = 3, minNeighbors = 3, minSize = (30, 30) )  I get the error "too many values to unpack" when I try faces, reject_levesl, level_weights = faceCascade.detectMultiScale( gray, scale_factor = 3, minNeighbors = 3, minSize = (30, 30), outputRejectLevels = True )  I get the error outputRejectLevels is an invalid keyword argument for this function. Am I doing something horribly wrong? I'm running the current beta version of Opencv 3 and am on Arch linux. When I try and run the classifier normally it works like a charm. Any help greatly appreciated!