org.opencv.features2d

Class MSER

java.lang.Object

org.opencv.core.Algorithm

org.opencv.features2d.Feature2D

org.opencv.features2d.MSER

public class MSER
extends Feature2D

Maximally stable extremal region extractor The class encapsulates all the parameters of the %MSER extraction algorithm (see [wiki article](http://en.wikipedia.org/wiki/Maximally_stable_extremal_regions)).

• there are two different implementation of %MSER: one for grey image, one for color image

• the grey image algorithm is taken from: CITE: nister2008linear ; the paper claims to be faster than union-find method; it actually get 1.5~2m/s on my centrino L7200 1.2GHz laptop.

• the color image algorithm is taken from: CITE: forssen2007maximally ; it should be much slower than grey image method ( 3~4 times ); the chi_table.h file is taken directly from paper's source code which is distributed under GPL.

• (Python) A complete example showing the use of the %MSER detector can be found at samples/python/mser.py

Field Summary

Fields inherited from class org.opencv.core.Algorithm

nativeObj

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	MSER(long addr)

Method Summary

Modifier and Type	Method and Description
static MSER	__fromPtr__(long addr)
static MSER	create() Full constructor for %MSER detector
static MSER	create(int _delta) Full constructor for %MSER detector
static MSER	create(int _delta, int _min_area) Full constructor for %MSER detector
static MSER	create(int _delta, int _min_area, int _max_area) Full constructor for %MSER detector
static MSER	create(int _delta, int _min_area, int _max_area, double _max_variation) Full constructor for %MSER detector
static MSER	create(int _delta, int _min_area, int _max_area, double _max_variation, double _min_diversity) Full constructor for %MSER detector
static MSER	create(int _delta, int _min_area, int _max_area, double _max_variation, double _min_diversity, int _max_evolution) Full constructor for %MSER detector
static MSER	create(int _delta, int _min_area, int _max_area, double _max_variation, double _min_diversity, int _max_evolution, double _area_threshold) Full constructor for %MSER detector
static MSER	create(int _delta, int _min_area, int _max_area, double _max_variation, double _min_diversity, int _max_evolution, double _area_threshold, double _min_margin) Full constructor for %MSER detector
static MSER	create(int _delta, int _min_area, int _max_area, double _max_variation, double _min_diversity, int _max_evolution, double _area_threshold, double _min_margin, int _edge_blur_size) Full constructor for %MSER detector
void	detectRegions(Mat image, List<MatOfPoint> msers, MatOfRect bboxes) Detect %MSER regions
protected void	finalize()
String	getDefaultName() Returns the algorithm string identifier.
int	getDelta()
int	getMaxArea()
int	getMinArea()
boolean	getPass2Only()
void	setDelta(int delta)
void	setMaxArea(int maxArea)
void	setMinArea(int minArea)
void	setPass2Only(boolean f)

Methods inherited from class org.opencv.features2d.Feature2D

compute, compute, defaultNorm, descriptorSize, descriptorType, detect, detect, detect, detect, detectAndCompute, detectAndCompute, empty, read, write

Methods inherited from class org.opencv.core.Algorithm

clear, getNativeObjAddr, save

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MSER

protected MSER(long addr)

Method Detail

__fromPtr__

public static MSER __fromPtr__(long addr)

create

public static MSER create(int _delta,
                          int _min_area,
                          int _max_area,
                          double _max_variation,
                          double _min_diversity,
                          int _max_evolution,
                          double _area_threshold,
                          double _min_margin,
                          int _edge_blur_size)

Full constructor for %MSER detector

Parameters:

_delta - it compares \((size_{i}-size_{i-delta})/size_{i-delta}\)

_min_area - prune the area which smaller than minArea

_max_area - prune the area which bigger than maxArea

_max_variation - prune the area have similar size to its children

_min_diversity - for color image, trace back to cut off mser with diversity less than min_diversity

_max_evolution - for color image, the evolution steps

_area_threshold - for color image, the area threshold to cause re-initialize

_min_margin - for color image, ignore too small margin

_edge_blur_size - for color image, the aperture size for edge blur

Returns:

automatically generated

create

public static MSER create(int _delta,
                          int _min_area,
                          int _max_area,
                          double _max_variation,
                          double _min_diversity,
                          int _max_evolution,
                          double _area_threshold,
                          double _min_margin)

Full constructor for %MSER detector

Parameters:

_delta - it compares \((size_{i}-size_{i-delta})/size_{i-delta}\)

_min_area - prune the area which smaller than minArea

_max_area - prune the area which bigger than maxArea

_max_variation - prune the area have similar size to its children

_min_diversity - for color image, trace back to cut off mser with diversity less than min_diversity

_max_evolution - for color image, the evolution steps

_area_threshold - for color image, the area threshold to cause re-initialize

_min_margin - for color image, ignore too small margin

Returns:

automatically generated

create

public static MSER create(int _delta,
                          int _min_area,
                          int _max_area,
                          double _max_variation,
                          double _min_diversity,
                          int _max_evolution,
                          double _area_threshold)

Full constructor for %MSER detector

Parameters:

_delta - it compares \((size_{i}-size_{i-delta})/size_{i-delta}\)

_min_area - prune the area which smaller than minArea

_max_area - prune the area which bigger than maxArea

_max_variation - prune the area have similar size to its children

_min_diversity - for color image, trace back to cut off mser with diversity less than min_diversity

_max_evolution - for color image, the evolution steps

_area_threshold - for color image, the area threshold to cause re-initialize

Returns:

automatically generated

create

public static MSER create(int _delta,
                          int _min_area,
                          int _max_area,
                          double _max_variation,
                          double _min_diversity,
                          int _max_evolution)

Full constructor for %MSER detector

Parameters:

_delta - it compares \((size_{i}-size_{i-delta})/size_{i-delta}\)

_min_area - prune the area which smaller than minArea

_max_area - prune the area which bigger than maxArea

_max_variation - prune the area have similar size to its children

_min_diversity - for color image, trace back to cut off mser with diversity less than min_diversity

_max_evolution - for color image, the evolution steps

Returns:

automatically generated

create

public static MSER create(int _delta,
                          int _min_area,
                          int _max_area,
                          double _max_variation,
                          double _min_diversity)

Full constructor for %MSER detector

Parameters:

_delta - it compares \((size_{i}-size_{i-delta})/size_{i-delta}\)

_min_area - prune the area which smaller than minArea

_max_area - prune the area which bigger than maxArea

_max_variation - prune the area have similar size to its children

_min_diversity - for color image, trace back to cut off mser with diversity less than min_diversity

Returns:

automatically generated

create

public static MSER create(int _delta,
                          int _min_area,
                          int _max_area,
                          double _max_variation)

Full constructor for %MSER detector

Parameters:

_delta - it compares \((size_{i}-size_{i-delta})/size_{i-delta}\)

_min_area - prune the area which smaller than minArea

_max_area - prune the area which bigger than maxArea

_max_variation - prune the area have similar size to its children

Returns:

automatically generated

create

public static MSER create(int _delta,
                          int _min_area,
                          int _max_area)

Full constructor for %MSER detector

Parameters:

_delta - it compares \((size_{i}-size_{i-delta})/size_{i-delta}\)

_min_area - prune the area which smaller than minArea

_max_area - prune the area which bigger than maxArea

Returns:

automatically generated

create

public static MSER create(int _delta,
                          int _min_area)

Full constructor for %MSER detector

Parameters:

_delta - it compares \((size_{i}-size_{i-delta})/size_{i-delta}\)

_min_area - prune the area which smaller than minArea

Returns:

automatically generated

create

public static MSER create(int _delta)

Full constructor for %MSER detector

Parameters:

_delta - it compares \((size_{i}-size_{i-delta})/size_{i-delta}\)

Returns:

automatically generated

create

public static MSER create()

Full constructor for %MSER detector

Returns:

automatically generated

getDefaultName

public String getDefaultName()

Description copied from class: Algorithm

Returns the algorithm string identifier. This string is used as top level xml/yml node tag when the object is saved to a file or string.

Overrides:

getDefaultName in class Feature2D

Returns:

automatically generated

getPass2Only

public boolean getPass2Only()

getDelta

public int getDelta()

getMaxArea

public int getMaxArea()

getMinArea

public int getMinArea()

detectRegions

public void detectRegions(Mat image,
                          List<MatOfPoint> msers,
                          MatOfRect bboxes)

Detect %MSER regions

Parameters:

image - input image (8UC1, 8UC3 or 8UC4, must be greater or equal than 3x3)

msers - resulting list of point sets

bboxes - resulting bounding boxes

setDelta

public void setDelta(int delta)

setMaxArea

public void setMaxArea(int maxArea)

setMinArea

public void setMinArea(int minArea)

setPass2Only

public void setPass2Only(boolean f)

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Feature2D

Throws:

Throwable