@interface MPSImageSIFTDescriptor : NSObject @property (nonatomic) float sigma; @property (nonatomic) unsigned long long layersPerOctave; @property (nonatomic) unsigned long long octaves; @property (nonatomic) BOOL upscale; @property (nonatomic) float contrastThreshold; @property (nonatomic) unsigned long long edgeThreshold; @property (nonatomic) float initialSigma; @property (nonatomic) unsigned long long imageBoundary; @property (nonatomic) float orientationRadius; @property (nonatomic) float orientationWeight; @property (nonatomic) unsigned long long orientationBins; @property (nonatomic) float orientationThreshold; @property (nonatomic) unsigned long long maximumKeyPoints; - (id)init; @end