GeneralFeatureDetector (feature 0.23 API)

java.lang.Object
- boofcv.alg.feature.detect.interest.GeneralFeatureDetector<I,D>

Type Parameters:

I - Input image type.

D - Image derivative type.
```
public class GeneralFeatureDetector<I extends boofcv.struct.image.ImageGray,D extends boofcv.struct.image.ImageGray>
extends java.lang.Object
```
Detects features which are local maximums and/or local minimums in the feature intensity image. A list of pixels to exclude as candidates can be provided. Image derivatives need to be computed externally and provided as needed. The passed in GeneralFeatureIntensity is used to determine if local maximums or minimums should be detected.

If a maximum number of features is specified then the N most intense features are returned. By default all found features are returned. Set to a value ≤ 0 to detect all features.

Field Summary

Fields
Modifier and Type	Field and Description
`protected boofcv.struct.QueueCorner`	`excludeMaximum`
`protected boofcv.struct.QueueCorner`	`excludeMinimum`
`protected NonMaxSuppression`	`extractor`
`protected boofcv.struct.QueueCorner`	`foundMaximum`
`protected boofcv.struct.QueueCorner`	`foundMinimum`
`protected GeneralFeatureIntensity<I,D>`	`intensity`
`protected int`	`maxFeatures`
`protected SelectNBestFeatures`	`selectBest`

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`GeneralFeatureDetector()`
	`GeneralFeatureDetector(GeneralFeatureIntensity<I,D> intensity, NonMaxSuppression extractor)` Specifies which algorithms to use and configures the detector.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boofcv.struct.image.GrayF32`	`getIntensity()`
`boofcv.struct.QueueCorner`	`getMaximums()` Returns a list of all the found maximums.
`boofcv.struct.QueueCorner`	`getMinimums()` Returns a list of all the found maximums.
`boolean`	`getRequiresGradient()` If the image gradient is required for calculations.
`boolean`	`getRequiresHessian()` If the image Hessian is required for calculations.
`float`	`getThreshold()` Returns the current feature extraction threshold.
`boolean`	`isDetectMaximums()` true if it will detector local maximums
`boolean`	`isDetectMinimums()` true if it will detector local minimums
`void`	`process(I image, D derivX, D derivY, D derivXX, D derivYY, D derivXY)` Computes point features from image gradients.
`void`	`setExcludeMaximum(boofcv.struct.QueueCorner exclude)` Specify points which are excluded when detecting maximums
`void`	`setExcludeMinimum(boofcv.struct.QueueCorner exclude)` Specify points which are excluded when detecting maximums
`void`	`setMaxFeatures(int numFeatures)` Turns on select best features and sets the number it should return.
`void`	`setSearchRadius(int radius)` Species the search radius for the feature
`void`	`setThreshold(float threshold)` Changes feature extraction threshold.

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

- Field Detail
  - foundMaximum
```
protected boofcv.struct.QueueCorner foundMaximum
```
  - foundMinimum
```
protected boofcv.struct.QueueCorner foundMinimum
```
  - excludeMaximum
```
protected boofcv.struct.QueueCorner excludeMaximum
```
  - excludeMinimum
```
protected boofcv.struct.QueueCorner excludeMinimum
```
  - selectBest
```
protected SelectNBestFeatures selectBest
```
  - maxFeatures
```
protected int maxFeatures
```
  - extractor
```
protected NonMaxSuppression extractor
```
  - intensity
```
protected GeneralFeatureIntensity<I extends boofcv.struct.image.ImageGray,D extends boofcv.struct.image.ImageGray> intensity
```
- Constructor Detail
  - GeneralFeatureDetector
```
public GeneralFeatureDetector(GeneralFeatureIntensity<I,D> intensity,
                              NonMaxSuppression extractor)
```
    Specifies which algorithms to use and configures the detector.
    
    Parameters:
    
    intensity - Computes how much like the feature the region around each pixel is.
    
    extractor - Extracts the corners from intensity image
  - GeneralFeatureDetector
```
protected GeneralFeatureDetector()
```
- Method Detail
  - process
```
public void process(I image,
                    D derivX,
                    D derivY,
                    D derivXX,
                    D derivYY,
                    D derivXY)
```
    Computes point features from image gradients.
    
    Parameters:
    
    image - Original image.
    
    derivX - image derivative in along the x-axis. Only needed if getRequiresGradient() is true.
    
    derivY - image derivative in along the y-axis. Only needed if getRequiresGradient() is true.
    
    derivXX - Second derivative. Only needed if getRequiresHessian() ()} is true.
    
    derivXY - Second derivative. Only needed if getRequiresHessian() ()} is true.
    
    derivYY - Second derivative. Only needed if getRequiresHessian() ()} is true.
  - setMaxFeatures
```
public void setMaxFeatures(int numFeatures)
```
    Turns on select best features and sets the number it should return. If a list of excluded features is passed in, then the maximum number of returned features is 'numFeatures' minus the number of excluded features.
    
    Parameters:
    
    numFeatures - Return at most this many features, which are the best.
  - getRequiresGradient
```
public boolean getRequiresGradient()
```
    If the image gradient is required for calculations.
    
    Returns:
    
    true if the image gradient is required.
  - getRequiresHessian
```
public boolean getRequiresHessian()
```
    If the image Hessian is required for calculations.
    
    Returns:
    
    true if the image Hessian is required.
  - getIntensity
```
public boofcv.struct.image.GrayF32 getIntensity()
```
  - setThreshold
```
public void setThreshold(float threshold)
```
    Changes feature extraction threshold.
    
    Parameters:
    
    threshold - The new feature extraction threshold.
  - getThreshold
```
public float getThreshold()
```
    Returns the current feature extraction threshold.
    
    Returns:
    
    feature extraction threshold.
  - setExcludeMaximum
```
public void setExcludeMaximum(boofcv.struct.QueueCorner exclude)
```
    Specify points which are excluded when detecting maximums
    
    Parameters:
    
    exclude - List of points being excluded
  - getMaximums
```
public boofcv.struct.QueueCorner getMaximums()
```
    Returns a list of all the found maximums.
    
    Returns:
    
    found point features
  - setExcludeMinimum
```
public void setExcludeMinimum(boofcv.struct.QueueCorner exclude)
```
    Specify points which are excluded when detecting maximums
    
    Parameters:
    
    exclude - List of points being excluded
  - getMinimums
```
public boofcv.struct.QueueCorner getMinimums()
```
    Returns a list of all the found maximums.
    
    Returns:
    
    found point features
  - isDetectMinimums
```
public boolean isDetectMinimums()
```
    true if it will detector local minimums
  - isDetectMaximums
```
public boolean isDetectMaximums()
```
    true if it will detector local maximums
  - setSearchRadius
```
public void setSearchRadius(int radius)
```
    Species the search radius for the feature
    
    Parameters:
    
    radius - Radius in pixels

Class GeneralFeatureDetector<I extends boofcv.struct.image.ImageGray,D extends boofcv.struct.image.ImageGray>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

foundMaximum

foundMinimum

excludeMaximum

excludeMinimum

selectBest

maxFeatures

extractor

intensity

Constructor Detail

GeneralFeatureDetector

GeneralFeatureDetector

Method Detail

process

setMaxFeatures

getRequiresGradient

getRequiresHessian

getIntensity

setThreshold

getThreshold

setExcludeMaximum

getMaximums

setExcludeMinimum

getMinimums

isDetectMinimums

isDetectMaximums

setSearchRadius