volume
Class Hessian
java.lang.Object
|
+--volume.Hessian
- public class Hessian
- extends java.lang.Object
This class implements computing the Hessian tensor matrix of an image, and computing the determinant
(to detect blobs) and largest eigenvalues (to detect edges).
Copyright (c) 1999-2004, Michael Abramoff. All rights reserved.
Method Summary |
static float[] |
det(float[] image,
int width,
double scale)
Compute the determinant of the Hessian matrix of image. |
static void |
largest(float[] result,
float[] image,
int width,
double scale)
Compute the largest Hessian eigenvectors of a 2-D image. |
static float[] |
largest(float[] image,
int width,
double scale)
Compute the largest Hessian eigenvectors of a 2-D image. |
static void |
smallest(float[] result,
float[] image,
int width,
double scale)
Compute the smallest Hessian eigenvectors of a 2-D image. |
static float[] |
smallest(float[] image,
int width,
double scale)
Compute the smallest Hessian eigenvectors of a 2-D image. |
Methods inherited from class java.lang.Object |
, clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Hessian
public Hessian()
smallest
public static void smallest(float[] result,
float[] image,
int width,
double scale)
- Compute the smallest Hessian eigenvectors of a 2-D image.
- Parameters:
result
- a float[] in which the result will be stored.image
- the imagewidth
- the width of image in pixels.scale
- the scale of the Gaussian used to compute the first and second order derivatives.
largest
public static void largest(float[] result,
float[] image,
int width,
double scale)
throws java.lang.IllegalArgumentException
- Compute the largest Hessian eigenvectors of a 2-D image.
- Parameters:
result
- a float[] in which the result will be stored.image
- the imagewidth
- the width of image in pixels.scale
- the scale of the Gaussian used to compute the first and second order derivatives.
largest
public static float[] largest(float[] image,
int width,
double scale)
- Compute the largest Hessian eigenvectors of a 2-D image.
- Parameters:
image
- the imagewidth
- the width of image in pixels.scale
- the scale of the Gaussian used to compute the first and second order derivatives.- Returns:
- result a float[] witht he largest eigenvalues.
smallest
public static float[] smallest(float[] image,
int width,
double scale)
- Compute the smallest Hessian eigenvectors of a 2-D image.
- Parameters:
image
- the imagewidth
- the width of image in pixels.scale
- the scale of the Gaussian used to compute the first and second order derivatives.- Returns:
- result a float[] witht he largest eigenvalues.
det
public static float[] det(float[] image,
int width,
double scale)
- Compute the determinant of the Hessian matrix of image.
L1 L2
where
L1 = (dxx + dyy) + SQRT((dxx - dyy)^2 + 4 dxy^2)
L2 = (dxx + dyy) - SQRT((dxx - dyy)^2 + 4 dxy^2)
- Parameters:
image
- the image from which the derivatives are computedwidth
- of image in pixels.scale
- the scale at which the derivatives will be computed as the stddev of the Gaussian.- Returns:
- L1 L2 as a float.
Submit a bug or feature
Copyright (c) 1997-2003 Michael Abramoff
Licensing available. All Rights Reserved.