boofcv.alg.filter.derivative

Class LaplacianEdge

java.lang.Object

boofcv.alg.filter.derivative.LaplacianEdge

public class LaplacianEdge
extends java.lang.Object

The Laplacian is convolved across an image to find second derivative of the image. It is often a faster way to compute the intensity of an edge than first derivative algorithms.

 This implementation of the laplacian has a 3 by 3 kernel.

            partial^2 f     partial^2 f
 f(x,y) =   ~~~~~~~~~~~  +  ~~~~~~~~~~~
            partial x^2     partial x^2

          [ 0   1   0 ]
 kernel = [ 1  -4   1 ]
          [ 0   1   0 ]
 

This formulation is derived by using the [-1 1 0] and [0 -1 1] difference kernels for the image derivative. Alternative formulations can be found using other kernels.

DEVELOPER NOTE: This is still a strong candidate for further optimizations due to redundant array accesses.

Field Summary

Fields

Modifier and Type	Field and Description
static Kernel2D_F32	kernel_F32
static Kernel2D_I32	kernel_I32

Constructor Summary

Constructors

Constructor and Description
LaplacianEdge()

Method Summary

Modifier and Type	Method and Description
static void	process(GrayF32 orig, GrayF32 deriv) Computes the Laplacian of 'orig'.
static void	process(GrayU8 orig, GrayF32 deriv)
static void	process(GrayU8 orig, GrayS16 deriv) Computes the Laplacian of input image.

Methods inherited from class java.lang.Object

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

Field Detail

kernel_I32

public static Kernel2D_I32 kernel_I32

kernel_F32

public static Kernel2D_F32 kernel_F32

Constructor Detail

LaplacianEdge

public LaplacianEdge()

Method Detail

process

public static void process(GrayU8 orig,
                           GrayS16 deriv)

Computes the Laplacian of input image.

Parameters:

orig - Input image. Not modified.

deriv - Where the Laplacian is written to. Modified.

process

public static void process(GrayU8 orig,
                           GrayF32 deriv)

process

public static void process(GrayF32 orig,
                           GrayF32 deriv)

Computes the Laplacian of 'orig'.

Parameters:

orig - Input image. Not modified.

deriv - Where the Laplacian is written to. Modified.