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SURF Constructor
Create a SURF detector using the specific values

Namespace:  Emgu.CV.XFeatures2D
Assembly:  Emgu.CV.World (in Emgu.CV.World.dll) Version: (
public SURF(
	double hessianThresh,
	int nOctaves = 4,
	int nOctaveLayers = 2,
	bool extended = true,
	bool upright = false


Type: SystemDouble
Only features with keypoint.hessian larger than that are extracted. good default value is ~300-500 (can depend on the average local contrast and sharpness of the image). user can further filter out some features based on their hessian values and other characteristics
nOctaves (Optional)
Type: SystemInt32
The number of octaves to be used for extraction. With each next octave the feature size is doubled
nOctaveLayers (Optional)
Type: SystemInt32
The number of layers within each octave
extended (Optional)
Type: SystemBoolean
false means basic descriptors (64 elements each), true means extended descriptors (128 elements each)
upright (Optional)
Type: SystemBoolean
False means that detector computes orientation of each feature. True means that the orientation is not computed (which is much, much faster). For example, if you match images from a stereo pair, or do image stitching, the matched features likely have very similar angles, and you can speed up feature extraction by setting upright=true.
See Also