Class for extracting Speeded Up Robust Features from an image.
Inheritance Hierarchy
OpenCvSharpDisposableObject
OpenCvSharpDisposableCvObject
OpenCvSharp.CPlusPlusAlgorithm
OpenCvSharp.CPlusPlusFeatureDetector
OpenCvSharp.CPlusPlusFeature2D
OpenCvSharp.CPlusPlusSURF
Namespace: OpenCvSharp.CPlusPlus
Assembly: OpenCvSharp.CPlusPlus (in OpenCvSharp.CPlusPlus.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax
The SURF type exposes the following members.
Constructors
| Name | Description | |
|---|---|---|
 | SURF |
Creates SURF default parameters
|
| SURF(Double, Int32, Int32, Boolean, Boolean) |
The SURF constructor.
|
Properties
| Name | Description | |
|---|---|---|
 | AllocatedMemory |
Gets or sets a memory address allocated by AllocMemory.
(Inherited from DisposableObject.) |
| AllocatedMemorySize |
Gets or sets the byte length of the allocated memory
(Inherited from DisposableObject.) |
 | CvPtr |
Native pointer of OpenCV structure
(Inherited from DisposableCvObject.) |
| DescriptorSize |
returns the descriptor size in float's (64 or 128)
|
| DescriptorType |
returns the descriptor type
|
| Extended |
false means that the basic descriptors (64 elements each) shall be computed.
true means that the extended descriptors (128 elements each) shall be computed
|
| HessianThreshold |
Threshold for the keypoint detector. Only features, whose hessian is larger than hessianThreshold
are retained by the detector. Therefore, the larger the value, the less keypoints you will get.
A good default value could be from 300 to 500, depending from the image contrast.
|
| Info |
Algorithm information
(Inherited from Algorithm.) |
| InfoPtr |
Pointer to algorithm information (cv::AlgorithmInfo*)
(Overrides FeatureDetectorInfoPtr.) |
| IsDisposed |
Gets a value indicating whether this instance has been disposed.
(Inherited from DisposableObject.) |
| IsEnabledDispose |
Gets or sets a value indicating whether you permit disposing this instance.
(Inherited from DisposableObject.) |
| Name |
Returns the algorithm name
(Inherited from Algorithm.) |
| NOctaveLayers |
The number of images within each octave of a gaussian pyramid. It is set to 2 by default.
|
| NOctaves |
The number of a gaussian pyramid octaves that the detector uses. It is set to 4 by default.
If you want to get very large features, use the larger value. If you want just small features, decrease it.
|
| Upright |
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.
|
Methods
| Name | Description | |
|---|---|---|
 | AllocGCHandle |
Pins the object to be allocated by cvSetData.
(Inherited from DisposableObject.) |
| AllocMemory |
Allocates the specified size of memory.
(Inherited from DisposableObject.) |
| Compute(Mat, KeyPoint, Mat) |
Compute the descriptors for a set of keypoints in an image.
(Inherited from Feature2D.) |
| Compute(IEnumerableMat, KeyPoint, IEnumerableMat) |
Compute the descriptors for a keypoints collection detected in image collection.
(Inherited from Feature2D.) |
| Detect(Mat, Mat) |
Detect keypoints in an image.
(Inherited from FeatureDetector.) |
| Detect(IEnumerableMat, IEnumerableMat) |
Detect keypoints in an image set.
(Inherited from FeatureDetector.) |
| Dispose |
Releases the resources
(Inherited from DisposableObject.) |
| Dispose(Boolean) |
Releases the resources
(Overrides Feature2DDispose(Boolean).) |
| Empty |
Return true if detector object is empty
(Inherited from FeatureDetector.) |
| Equals | (Inherited from Object.) |
| Finalize |
Destructor
(Inherited from DisposableObject.) |
| GetAlgorithm |
Returns the algorithm parameter
(Inherited from Algorithm.) |
| GetBool |
Returns the algorithm parameter
(Inherited from Algorithm.) |
| GetDouble |
Returns the algorithm parameter
(Inherited from Algorithm.) |
| GetHashCode | (Inherited from Object.) |
| GetInt |
Returns the algorithm parameter
(Inherited from Algorithm.) |
| GetMat |
Returns the algorithm parameter
(Inherited from Algorithm.) |
| GetMatVector |
Returns the algorithm parameter
(Inherited from Algorithm.) |
| GetParams | (Inherited from Algorithm.) |
| GetString |
Returns the algorithm parameter
(Inherited from Algorithm.) |
| GetType | (Inherited from Object.) |
| MemberwiseClone | (Inherited from Object.) |
| NotifyMemoryPressure |
Notifies the allocated size of memory.
(Inherited from DisposableObject.) |
| ParamHelp | (Inherited from Algorithm.) |
| ParamType | (Inherited from Algorithm.) |
| Release |
Clean up any resources being used.
(Inherited from Algorithm.) |
| Run(InputArray, Mat) |
detects keypoints using fast multi-scale Hessian detector
|
| Run(InputArray, InputArray, KeyPoint, OutputArray, Boolean) |
detects keypoints and computes the SURF descriptors for them. [useProvidedKeypoints = true]
|
| Run(InputArray, InputArray, KeyPoint, Single, Boolean) |
detects keypoints and computes the SURF descriptors for them. [useProvidedKeypoints = true]
|
| SetAlgorithm |
Sets the algorithm parameter
(Inherited from Algorithm.) |
| SetBool |
Sets the algorithm parameter
(Inherited from Algorithm.) |
| SetDouble |
Sets the algorithm parameter
(Inherited from Algorithm.) |
| SetInt |
Sets the algorithm parameter
(Inherited from Algorithm.) |
| SetMat |
Sets the algorithm parameter
(Inherited from Algorithm.) |
| SetMatVector |
Sets the algorithm parameter
(Inherited from Algorithm.) |
| SetString |
Sets the algorithm parameter
(Inherited from Algorithm.) |
| ThrowIfDisposed |
If this object is disposed, then ObjectDisposedException is thrown.
(Inherited from DisposableObject.) |
| ToString |
Returns a string that represents this Algorithm.
(Inherited from Algorithm.) |
Fields
| Name | Description | |
|---|---|---|
 | dataHandle |
Gets or sets a handle which allocates using cvSetData.
(Inherited from DisposableObject.) |
| ptr |
Data pointer
(Inherited from DisposableCvObject.) |
See Also