Class HessianBlobIntensity


  • public class HessianBlobIntensity
    extends java.lang.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|

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  HessianBlobIntensity.Type
      Different types of Hessian blob detectors
    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static void determinant​(GrayF32 featureIntensity, GrayF32 hessianXX, GrayF32 hessianYY, GrayF32 hessianXY)
      Feature intensity using the Hessian matrix's determinant.
      static void determinant​(GrayF32 featureIntensity, GrayS16 hessianXX, GrayS16 hessianYY, GrayS16 hessianXY)
      Feature intensity using the Hessian matrix's determinant.
      static void trace​(GrayF32 featureIntensity, GrayF32 hessianXX, GrayF32 hessianYY)
      Feature intensity using the trace of the Hessian matrix.
      static void trace​(GrayF32 featureIntensity, GrayS16 hessianXX, GrayS16 hessianYY)
      Feature intensity using the trace of the Hessian matrix.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • HessianBlobIntensity

        public HessianBlobIntensity()
    • Method Detail

      • 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.