HoughTransforms (ImgLib2 Javadocs 0-SNAPSHOT API)

java.lang.Object
- net.imglib2.algorithm.hough.HoughTransforms<T>

Type Parameters:

T - the data type of the input image.
```
public class HoughTransforms<T extends RealType<T> & Comparable<T>>
extends Object
```
This class provides static methods used to detect imperfect shapes in two-dimensional images through the use of the Hough Transform.

Author:

Larry Lindsey, Yili Zhao, Gabe Selzer

Field Summary

Fields
Modifier and Type Field and Description

static int DEFAULT_THETA

Fields
Modifier and Type	Field and Description
`static int`	`DEFAULT_THETA`

Constructor Summary

Constructors
Constructor and Description

HoughTransforms()

Constructors
Constructor and Description
`HoughTransforms()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static double`	`getIntercept(long rho, long theta)` Method used to convert the {rho, theta} output of the `voteLines(net.imglib2.RandomAccessibleInterval<T>, net.imglib2.RandomAccessibleInterval<U>)` algorithm into a more useful y-intercept value.
`static double`	`getSlope(long theta)` Method used to convert the {rho, theta} output of the `voteLines(net.imglib2.RandomAccessibleInterval<T>, net.imglib2.RandomAccessibleInterval<U>)` algorithm into a more useful slope value.
`static long[]`	`getVotespaceSize(Dimensions dimensions)` Returns the size of the vote space output image given an input `RandomAccessibleInterval`.
`static long[]`	`getVotespaceSize(Dimensions dimensions, int nTheta)` Returns the size of the vote space output image given an input `RandomAccessibleInterval`.
`static long[]`	`getVotespaceSize(int nRho, int nTheta)` Returns the size of the voteSpace output image given desired `nRho` and `nTheta` values.
`static <T extends IntegerType<T>> List<Point>`	`pickLinePeaks(RandomAccessibleInterval<T> voteSpace, long threshold)` Pick vote space peaks with a `LocalExtrema`.
`static <T extends Comparable<T>> List<Point>`	`pickLinePeaks(RandomAccessibleInterval<T> voteSpace, T minPeak)` Pick vote space peaks with a `LocalExtrema`.
`static <T extends Comparable<T>,U extends IntegerType<U>> void`	`voteLines(RandomAccessibleInterval<T> input, RandomAccessibleInterval<U> votespace)` Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.
`static <T extends Comparable<T>,U extends IntegerType<U>> void`	`voteLines(RandomAccessibleInterval<T> input, RandomAccessibleInterval<U> votespace, int nTheta)` Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.
`static <T extends Comparable<T>,U extends IntegerType<U>> void`	`voteLines(RandomAccessibleInterval<T> input, RandomAccessibleInterval<U> votespace, int nTheta, int nRho)` Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.
`static <T,U extends IntegerType<U>> void`	`voteLines(RandomAccessibleInterval<T> input, RandomAccessibleInterval<U> votespace, int nTheta, int nRho, Predicate<T> filter)` Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.
`static <T extends Comparable<T>,U extends IntegerType<U>> void`	`voteLines(RandomAccessibleInterval<T> input, RandomAccessibleInterval<U> votespace, int nTheta, int nRho, T threshold)` Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.

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

- Field Detail
 - DEFAULT_THETA
```
public static final int DEFAULT_THETA
```
 See Also:
 
 Constant Field Values
- Constructor Detail
 - HoughTransforms
```
public HoughTransforms()
```
- Method Detail
 - getVotespaceSize
```
public static long[] getVotespaceSize(Dimensions dimensions)
```
 Returns the size of the vote space output image given an input RandomAccessibleInterval.
 
 Parameters:
 
 dimensions - - the Dimensions over which the Hough Line Transform will be run
 
 Returns:
 
 long[] - the dimensions of the vote space image
 - getVotespaceSize
```
public static long[] getVotespaceSize(Dimensions dimensions,
 int nTheta)
```
 Returns the size of the vote space output image given an input RandomAccessibleInterval.
 
 Parameters:
 
 dimensions - - the Dimensions over which the Hough Line Transform will be run
 
 nTheta - - the number of theta bins.
 
 Returns:
 
 long[] - the dimensions of the vote space image
 - getVotespaceSize
```
public static long[] getVotespaceSize(int nRho,
 int nTheta)
```
 Returns the size of the voteSpace output image given desired nRho and nTheta values.
 
 Parameters:
 
 nRho - - the number of bins for rho resolution
 
 nTheta - - the number of bins for theta resolution
 
 Returns:
 
 long[] - the dimensions of the vote space image.
 - pickLinePeaks
```
public static <T extends IntegerType<T>> List<Point> pickLinePeaks(RandomAccessibleInterval<T> voteSpace,
 long threshold)
```
 Pick vote space peaks with a LocalExtrema.
 
 Parameters:
 
 voteSpace - - the RandomAccessibleInterval containing the output of a Hough Transform vote
 
 threshold - - the IntegerType at and below which maxima will be ignored
 
 Returns:
 
 List<Point> - a list of all of the local maxima of the voteSpace
 - pickLinePeaks
```
public static <T extends Comparable<T>> List<Point> pickLinePeaks(RandomAccessibleInterval<T> voteSpace,
 T minPeak)
```
 Pick vote space peaks with a LocalExtrema.
 
 Parameters:
 
 voteSpace - - the RandomAccessibleInterval containing the output of a Hough Transform vote
 
 minPeak - - the Comparable at and below which maxima will be ignored
 
 Returns:
 
 List<Point> - a list of all of the local maxima of the voteSpace.
 - voteLines
```
public static <T extends Comparable<T>,U extends IntegerType> void voteLines(RandomAccessibleInterval<T> input,
 RandomAccessibleInterval votespace)
```
 Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.
 
 Parameters:
 
 input - - the RandomAccessibleInterval to run the Hough Line Transform over
 
 votespace - - the RandomAccessibleInterval in which the results are stored
 - voteLines
```
public static <T extends Comparable<T>,U extends IntegerType> void voteLines(RandomAccessibleInterval<T> input,
 RandomAccessibleInterval votespace,
 int nTheta)
```
 Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.
 
 Parameters:
 
 input - - the RandomAccessibleInterval to run the Hough Line Transform over
 
 votespace - - the RandomAccessibleInterval in which the results are stored
 
 nTheta - - the number of bins for theta resolution
 - voteLines
```
public static <T extends Comparable<T>,U extends IntegerType> void voteLines(RandomAccessibleInterval<T> input,
 RandomAccessibleInterval votespace,
 int nTheta,
 int nRho)
```
 Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.
 
 Parameters:
 
 input - - the RandomAccessibleInterval to run the Hough Line Transform over
 
 votespace - - the RandomAccessibleInterval in which the results are stored
 
 nTheta - - the number of bins for theta resolution
 
 nRho - - the number of bins for rho resolution
 - voteLines
```
public static <T extends Comparable<T>,U extends IntegerType> void voteLines(RandomAccessibleInterval<T> input,
 RandomAccessibleInterval votespace,
 int nTheta,
 int nRho,
 T threshold)
```
 Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.
 
 Parameters:
 
 input - - the RandomAccessibleInterval to run the Hough Line Transform over
 
 votespace - - the RandomAccessibleInterval in which the results are stored
 
 nTheta - - the number of bins for theta resolution
 
 nRho - - the number of bins for rho resolution
 
 threshold - - the minimum value allowed by the populator. Any input less than this value will be disregarded by the populator.
 - voteLines
```
public static <T,U extends IntegerType> void voteLines(RandomAccessibleInterval<T> input,
 RandomAccessibleInterval votespace,
 int nTheta,
 int nRho,
 Predicate<T> filter)
```
 Runs a Hough Line Tranform on an image and populates the vote space parameter with the results.
 Vote space here has two dimensions: rho and theta. theta is measured in radians [-pi/2 pi/2), rho is measured in [-rhoMax, rhoMax).
 
 Lines are modeled as
```
 l(t) = | x | = rho * | cos(theta) | + t * | sin(theta) |
 | y | | -sin(theta) | | cos(theta) |
 
```
 In other words, rho represents the signed minimum distance from the image origin to the line, and theta indicates the angle between the row-axis and the minimum offset vector.
 
 For a given point, then, votes are placed along the curve
```
 rho = y * sin( theta ) + x * cos( theta )
 
```
 It is important to note that the interval of the first dimension of the vote space image is NOT [-maxRho, maxRho) but instead [0, maxRho * 2); the same applies to the second dimension of the vote space as well. Thus if pickLinePeaks(net.imglib2.RandomAccessibleInterval<T>, long) is not used to retrieve the maxima from the vote space, the vote space will have to be translated by -maxRho in dimension 0 to get the correct rho and theta values from the vote space.
 Parameters:
 
 input - - the RandomAccessibleInterval to run the Hough Line Transform over
 
 votespace - - the RandomAccessibleInterval in which the results are stored
 
 nTheta - - the number of bins for theta resolution
 
 nRho - - the number of bins for rho resolution
 
 filter - - a Predicate judging whether or not the a value is above the minimum value allowed by the populator. Any input less than or equal to this value will be disregarded by the populator.
 - getIntercept
```
public static double getIntercept(long rho,
 long theta)
```
 Method used to convert the {rho, theta} output of the voteLines(net.imglib2.RandomAccessibleInterval<T>, net.imglib2.RandomAccessibleInterval) algorithm into a more useful y-intercept value. Used with getSlope(long) to create line equations.
 
 Parameters:
 
 rho - - the rho of the line
 
 theta - - the theta of the line
 
 Returns:
 
 double - the y-intercept of the line
 - getSlope
```
public static double getSlope(long theta)
```
 Method used to convert the {rho, theta} output of the voteLines(net.imglib2.RandomAccessibleInterval<T>, net.imglib2.RandomAccessibleInterval) algorithm into a more useful slope value. Used with getIntercept(long, long) to create line equations.
 
 Parameters:
 
 theta - - the theta of the line
 
 Returns:
 
 double - the y-intercept of the line

Class HoughTransforms<T extends RealType<T> & Comparable<T>>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_THETA

Constructor Detail

HoughTransforms

Method Detail

getVotespaceSize

getVotespaceSize

getVotespaceSize

pickLinePeaks

pickLinePeaks

voteLines

voteLines

voteLines

voteLines

voteLines

getIntercept

getSlope