SURF_CUDA (JavaCPP Presets for OpenCV 4.7.0-1.5.9 API)

java.lang.Object
- org.opencv.xfeatures2d.SURF_CUDA

```
public class SURF_CUDA
extends Object
```
Class used for extracting Speeded Up Robust Features (SURF) from an image. : The class SURF_CUDA implements Speeded Up Robust Features descriptor. There is a fast multi-scale Hessian keypoint detector that can be used to find the keypoints (which is the default option). But the descriptors can also be computed for the user-specified keypoints. Only 8-bit grayscale images are supported. The class SURF_CUDA can store results in the GPU and CPU memory. It provides functions to convert results between CPU and GPU version ( uploadKeypoints, downloadKeypoints, downloadDescriptors ). The format of CPU results is the same as SURF results. GPU results are stored in GpuMat. The keypoints matrix is \(\texttt{nFeatures} \times 7\) matrix with the CV_32FC1 type.
- keypoints.ptr<float>(X_ROW)[i] contains x coordinate of the i-th feature.
- keypoints.ptr<float>(Y_ROW)[i] contains y coordinate of the i-th feature.
- keypoints.ptr<float>(LAPLACIAN_ROW)[i] contains the laplacian sign of the i-th feature.
- keypoints.ptr<float>(OCTAVE_ROW)[i] contains the octave of the i-th feature.
- keypoints.ptr<float>(SIZE_ROW)[i] contains the size of the i-th feature.
- keypoints.ptr<float>(ANGLE_ROW)[i] contain orientation of the i-th feature.
- keypoints.ptr<float>(HESSIAN_ROW)[i] contains the response of the i-th feature.
The descriptors matrix is \(\texttt{nFeatures} \times \texttt{descriptorSize}\) matrix with the CV_32FC1 type. The class SURF_CUDA uses some buffers and provides access to it. All buffers can be safely released between function calls. SEE: SURF Note:
- An example for using the SURF keypoint matcher on GPU can be found at opencv_source_code/samples/gpu/surf_keypoint_matcher.cpp

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`ANGLE_ROW`
`static int`	`HESSIAN_ROW`
`static int`	`LAPLACIAN_ROW`
`protected long`	`nativeObj`
`static int`	`OCTAVE_ROW`
`static int`	`ROWS_COUNT`
`static int`	`SIZE_ROW`
`static int`	`X_ROW`
`static int`	`Y_ROW`

Constructor Summary

Constructors
Modifier Constructor and Description

protected SURF_CUDA(long addr)

Constructors
Modifier	Constructor and Description
`protected`	`SURF_CUDA(long addr)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static SURF_CUDA`	`__fromPtr__(long addr)`
`static SURF_CUDA`	`create(double _hessianThreshold)`
`static SURF_CUDA`	`create(double _hessianThreshold, int _nOctaves)`
`static SURF_CUDA`	`create(double _hessianThreshold, int _nOctaves, int _nOctaveLayers)`
`static SURF_CUDA`	`create(double _hessianThreshold, int _nOctaves, int _nOctaveLayers, boolean _extended)`
`static SURF_CUDA`	`create(double _hessianThreshold, int _nOctaves, int _nOctaveLayers, boolean _extended, float _keypointsRatio)`
`static SURF_CUDA`	`create(double _hessianThreshold, int _nOctaves, int _nOctaveLayers, boolean _extended, float _keypointsRatio, boolean _upright)`
`int`	`defaultNorm()`
`int`	`descriptorSize()`
`protected void`	`finalize()`
`boolean`	`get_extended()`
`double`	`get_hessianThreshold()`
`float`	`get_keypointsRatio()`
`int`	`get_nOctaveLayers()`
`int`	`get_nOctaves()`
`boolean`	`get_upright()`
`long`	`getNativeObjAddr()`

Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - nativeObj
```
protected final long nativeObj
```
  - X_ROW
```
public static final int X_ROW
```
    See Also:
    
    Constant Field Values
  - Y_ROW
```
public static final int Y_ROW
```
    See Also:
    
    Constant Field Values
  - LAPLACIAN_ROW
```
public static final int LAPLACIAN_ROW
```
    See Also:
    
    Constant Field Values
  - OCTAVE_ROW
```
public static final int OCTAVE_ROW
```
    See Also:
    
    Constant Field Values
  - SIZE_ROW
```
public static final int SIZE_ROW
```
    See Also:
    
    Constant Field Values
  - ANGLE_ROW
```
public static final int ANGLE_ROW
```
    See Also:
    
    Constant Field Values
  - HESSIAN_ROW
```
public static final int HESSIAN_ROW
```
    See Also:
    
    Constant Field Values
  - ROWS_COUNT
```
public static final int ROWS_COUNT
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - SURF_CUDA
```
protected SURF_CUDA(long addr)
```
- Method Detail
  - getNativeObjAddr
```
public long getNativeObjAddr()
```
  - __fromPtr__
```
public static SURF_CUDA __fromPtr__(long addr)
```
  - create
```
public static SURF_CUDA create(double _hessianThreshold,
                               int _nOctaves,
                               int _nOctaveLayers,
                               boolean _extended,
                               float _keypointsRatio,
                               boolean _upright)
```
    Parameters:
    
    _hessianThreshold - Threshold for hessian keypoint detector used in SURF.
    
    _nOctaves - Number of pyramid octaves the keypoint detector will use.
    
    _nOctaveLayers - Number of octave layers within each octave.
    
    _extended - Extended descriptor flag (true - use extended 128-element descriptors; false - use 64-element descriptors).
    
    _keypointsRatio -
    
    _upright - Up-right or rotated features flag (true - do not compute orientation of features; false - compute orientation).
    
    Returns:
    
    automatically generated
  - create
```
public static SURF_CUDA create(double _hessianThreshold,
                               int _nOctaves,
                               int _nOctaveLayers,
                               boolean _extended,
                               float _keypointsRatio)
```
    Parameters:
    
    _hessianThreshold - Threshold for hessian keypoint detector used in SURF.
    
    _nOctaves - Number of pyramid octaves the keypoint detector will use.
    
    _nOctaveLayers - Number of octave layers within each octave.
    
    _extended - Extended descriptor flag (true - use extended 128-element descriptors; false - use 64-element descriptors).
    
    _keypointsRatio - false - compute orientation).
    
    Returns:
    
    automatically generated
  - create
```
public static SURF_CUDA create(double _hessianThreshold,
                               int _nOctaves,
                               int _nOctaveLayers,
                               boolean _extended)
```
    Parameters:
    
    _hessianThreshold - Threshold for hessian keypoint detector used in SURF.
    
    _nOctaves - Number of pyramid octaves the keypoint detector will use.
    
    _nOctaveLayers - Number of octave layers within each octave.
    
    _extended - Extended descriptor flag (true - use extended 128-element descriptors; false - use 64-element descriptors). false - compute orientation).
    
    Returns:
    
    automatically generated
  - create
```
public static SURF_CUDA create(double _hessianThreshold,
                               int _nOctaves,
                               int _nOctaveLayers)
```
    Parameters:
    
    _hessianThreshold - Threshold for hessian keypoint detector used in SURF.
    
    _nOctaves - Number of pyramid octaves the keypoint detector will use.
    
    _nOctaveLayers - Number of octave layers within each octave. 64-element descriptors). false - compute orientation).
    
    Returns:
    
    automatically generated
  - create
```
public static SURF_CUDA create(double _hessianThreshold,
                               int _nOctaves)
```
    Parameters:
    
    _hessianThreshold - Threshold for hessian keypoint detector used in SURF.
    
    _nOctaves - Number of pyramid octaves the keypoint detector will use. 64-element descriptors). false - compute orientation).
    
    Returns:
    
    automatically generated
  - create
```
public static SURF_CUDA create(double _hessianThreshold)
```
    Parameters:
    
    _hessianThreshold - Threshold for hessian keypoint detector used in SURF. 64-element descriptors). false - compute orientation).
    
    Returns:
    
    automatically generated
  - descriptorSize
```
public int descriptorSize()
```
  - defaultNorm
```
public int defaultNorm()
```
  - get_hessianThreshold
```
public double get_hessianThreshold()
```
  - get_nOctaves
```
public int get_nOctaves()
```
  - get_nOctaveLayers
```
public int get_nOctaveLayers()
```
  - get_extended
```
public boolean get_extended()
```
  - get_upright
```
public boolean get_upright()
```
  - get_keypointsRatio
```
public float get_keypointsRatio()
```
  - finalize
```
protected void finalize()
                 throws Throwable
```
    Overrides:
    
    finalize in class Object
    
    Throws:
    
    Throwable

Class SURF_CUDA

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

nativeObj

X_ROW

Y_ROW

LAPLACIAN_ROW

OCTAVE_ROW

SIZE_ROW

ANGLE_ROW

HESSIAN_ROW

ROWS_COUNT

Constructor Detail

SURF_CUDA

Method Detail

getNativeObjAddr

__fromPtr__

create

create

create

create

create

create

descriptorSize

defaultNorm

get_hessianThreshold

get_nOctaves

get_nOctaveLayers

get_extended

get_upright

get_keypointsRatio

finalize

fromPtr