boofcv.alg.filter.derivative

Class HessianThree

java.lang.Object

boofcv.alg.filter.derivative.HessianThree

public class HessianThree
extends java.lang.Object

Computes the second derivative (Hessian) of an image using. This hessian is derived by using the same gradient function used in GradientThree, which uses a kernel of [-1 0 1].

WARNING: It is computationally more expensive to compute the Hessian with this operation than applying the gradient operator multiple times. However, this does not require the creation additional storage to save intermediate results.

Kernel for ∂ ²f/∂ x² and ∂²f /∂ y² is [1 0 -2 0 1] and ∂²f/∂ x∂y is:

Field Summary

1	0	-1
0	0	0
-1	0	1

Fields

Modifier and Type	Field and Description
static Kernel2D_F32	kernelCross_F32
static Kernel2D_I32	kernelCross_I32
static Kernel1D_F32	kernelXXYY_F32
static Kernel1D_I32	kernelXXYY_I32

Constructor Summary

Constructors

Constructor and Description
HessianThree()

Method Summary

Modifier and Type	Method and Description
static void	process(GrayF32 orig, GrayF32 derivXX, GrayF32 derivYY, GrayF32 derivXY, ImageBorder_F32 border) Computes the second derivative of an GrayU8 along the x and y axes.
static void	process(GrayU8 orig, GrayS16 derivXX, GrayS16 derivYY, GrayS16 derivXY, ImageBorder_S32 border) Computes the second derivative of an GrayU8 along the x and y axes.

Methods inherited from class java.lang.Object

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

Field Detail

kernelXXYY_I32

public static Kernel1D_I32 kernelXXYY_I32

kernelCross_I32

public static Kernel2D_I32 kernelCross_I32

kernelXXYY_F32

public static Kernel1D_F32 kernelXXYY_F32

kernelCross_F32

public static Kernel2D_F32 kernelCross_F32

Constructor Detail

HessianThree

public HessianThree()

Method Detail

process

public static void process(GrayU8 orig,
                           GrayS16 derivXX,
                           GrayS16 derivYY,
                           GrayS16 derivXY,
                           ImageBorder_S32 border)

Computes the second derivative of an GrayU8 along the x and y axes.

Parameters:

orig - Which which is to be differentiated. Not Modified.

derivXX - Second derivative along the x-axis. Modified.

derivYY - Second derivative along the y-axis. Modified.

derivXY - Second cross derivative. Modified.

border - Specifies how the image border is handled. If null the border is not processed.

process

public static void process(GrayF32 orig,
                           GrayF32 derivXX,
                           GrayF32 derivYY,
                           GrayF32 derivXY,
                           ImageBorder_F32 border)

Computes the second derivative of an GrayU8 along the x and y axes.

Parameters:

orig - Which which is to be differentiated. Not Modified.

derivXX - Second derivative along the x-axis. Modified.

derivYY - Second derivative along the y-axis. Modified.

derivXY - Second cross derivative. Modified.

border - Specifies how the image border is handled. If null the border is not processed.