Class HessianBlobIntensity

java.lang.Object
boofcv.alg.feature.detect.intensity.HessianBlobIntensity

public class HessianBlobIntensity extends Object

Detects "blob" intensity using the image's second derivative. The Hessian (second derivative) matrix is defined as [ Ixx , Ixy ; Ixy , Iyy], where the subscript indicates a partial derivative of the input image. The trace and determinant of this matrix is commonly used to detect interest point intensities. These tend to be at a peak for blobs and circular type objects. The trace is commonly referred to as the Laplacian.

  • Determinant: Dxx*Dyy + Dxy2
  • Trace: |Dxx + Dyy|

  • Constructor Details

    • HessianBlobIntensity

      public HessianBlobIntensity()
  • Method Details

    • determinant

      public static void determinant(GrayF32 featureIntensity, GrayF32 hessianXX, GrayF32 hessianYY, GrayF32 hessianXY)
      Feature intensity using the Hessian matrix's determinant.
      Parameters:
      featureIntensity - Output feature intensity. Modified.
      hessianXX - Second derivative along x-axis. Not modified.
      hessianYY - Second derivative along y-axis. Not modified.
      hessianXY - Second derivative along x-axis and y-axis. Not modified.
    • trace

      public static void trace(GrayF32 featureIntensity, GrayF32 hessianXX, GrayF32 hessianYY)
      Feature intensity using the trace of the Hessian matrix. This is also known as the Laplacian.
      Parameters:
      featureIntensity - Output feature intensity. Modified.
      hessianXX - Second derivative along x-axis. Not modified.
      hessianYY - Second derivative along y-axis. Not modified.
    • determinant

      public static void determinant(GrayF32 featureIntensity, GrayS16 hessianXX, GrayS16 hessianYY, GrayS16 hessianXY)
      Feature intensity using the Hessian matrix's determinant.
      Parameters:
      featureIntensity - Output feature intensity. Modified.
      hessianXX - Second derivative along x-axis. Not modified.
      hessianYY - Second derivative along y-axis. Not modified.
      hessianXY - Second derivative along x-axis and y-axis. Not modified.
    • trace

      public static void trace(GrayF32 featureIntensity, GrayS16 hessianXX, GrayS16 hessianYY)
      Feature intensity using the trace of the Hessian matrix. This is also known as the Laplacian.
      Parameters:
      featureIntensity - Output feature intensity. Modified.
      hessianXX - Second derivative along x-axis. Not modified.
      hessianYY - Second derivative along y-axis. Not modified.