This file is indexed.

/usr/include/vtk-6.3/vtkLinkEdgels.h is in libvtk6-dev 6.3.0+dfsg1-11build1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkLinkEdgels.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
// .NAME vtkLinkEdgels - links edgels together to form digital curves.
// .SECTION Description
// vtkLinkEdgels links edgels into digital curves which are then stored
// as polylines. The algorithm works one pixel at a time only looking at
// its immediate neighbors. There is a GradientThreshold that can be set
// that eliminates any pixels with a smaller gradient value. This can
// be used as the lower threshold of a two value edgel thresholding.
//
// For the remaining edgels, links are first tried for the four
// connected neighbors.  A successful neighbor will satisfy three
// tests. First both edgels must be above the gradient
// threshold. Second, the difference between the orientation between
// the two edgels (Alpha) and each edgels orientation (Phi) must be
// less than LinkThreshold. Third, the difference between the two
// edgels Phi values must be less than PhiThreshold.
// The most successful link is selected. The measure is simply the
// sum of the three angle differences (actually stored as the sum of
// the cosines). If none of the four connect neighbors succeeds, then
// the eight connect neighbors are examined using the same method.
//
// This filter requires gradient information so you will need to use
// a vtkImageGradient at some point prior to this filter.  Typically
// a vtkNonMaximumSuppression filter is also used. vtkThresholdEdgels
// can be used to complete the two value edgel thresholding as used
// in a Canny edge detector. The vtkSubpixelPositionEdgels filter
// can also be used after this filter to adjust the edgel locations.

// .SECTION see also
// vtkImageData vtkImageGradient vtkImageNonMaximumSuppression

#ifndef vtkLinkEdgels_h
#define vtkLinkEdgels_h

#include "vtkFiltersGeneralModule.h" // For export macro
#include "vtkPolyDataAlgorithm.h"

class vtkCellArray;
class vtkDataArray;
class vtkDoubleArray;
class vtkPoints;

class VTKFILTERSGENERAL_EXPORT vtkLinkEdgels : public vtkPolyDataAlgorithm
{
public:
  vtkTypeMacro(vtkLinkEdgels,vtkPolyDataAlgorithm);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Construct instance of vtkLinkEdgels with GradientThreshold set to
  // 0.1, PhiThreshold set to 90 degrees and LinkThreshold set to 90 degrees.
  static vtkLinkEdgels *New();

  // Description:
  // Set/Get the threshold for Phi vs. Alpha link thresholding.
  vtkSetMacro(LinkThreshold,double);
  vtkGetMacro(LinkThreshold,double);

  // Description:
  // Set/get the threshold for Phi vs. Phi link thresholding.
  vtkSetMacro(PhiThreshold,double);
  vtkGetMacro(PhiThreshold,double);

  // Description:
  // Set/Get the threshold for image gradient thresholding.
  vtkSetMacro(GradientThreshold,double);
  vtkGetMacro(GradientThreshold,double);

protected:
  vtkLinkEdgels();
  ~vtkLinkEdgels() {}

  virtual int RequestData(vtkInformation *, vtkInformationVector **, vtkInformationVector *);
  virtual int FillInputPortInformation(int port, vtkInformation *info);

  void LinkEdgels(int xdim, int ydim,double *image, vtkDataArray *inVectors,
                  vtkCellArray *newLines, vtkPoints *newPts,
                  vtkDoubleArray *outScalars, vtkDoubleArray *outVectors,
                  int z);
  double GradientThreshold;
  double PhiThreshold;
  double LinkThreshold;
private:
  vtkLinkEdgels(const vtkLinkEdgels&);  // Not implemented.
  void operator=(const vtkLinkEdgels&);  // Not implemented.
};

#endif