tesseract-ocr/classify/outfeat.h File Reference

#include "ocrfeatures.h"
#include "fpoint.h"
#include "mfoutline.h"

Go to the source code of this file.

Defines
#define	MAX_OUTLINE_FEATURES   (100)
Enumerations
enum	OUTLINE_FEAT_PARAM_NAME { OutlineFeatX, OutlineFeatY, OutlineFeatLength, OutlineFeatDir }
Functions
void	AddOutlineFeatureToSet (FPOINT *Start, FPOINT *End, FEATURE_SET FeatureSet)
void	ConvertToOutlineFeatures (MFOUTLINE Outline, FEATURE_SET FeatureSet)
void	NormalizeOutlineX (FEATURE_SET FeatureSet)

---

Define Documentation

#define MAX_OUTLINE_FEATURES   (100)

Definition at line 35 of file outfeat.h.

---

Enumeration Type Documentation

enum OUTLINE_FEAT_PARAM_NAME

---------------------------------------------------------------------------- Include Files and Type Defines ----------------------------------------------------------------------------

Enumerator:

OutlineFeatX
OutlineFeatY
OutlineFeatLength
OutlineFeatDir

Definition at line 28 of file outfeat.h.

             {
  OutlineFeatX,
  OutlineFeatY,
  OutlineFeatLength,
  OutlineFeatDir
} OUTLINE_FEAT_PARAM_NAME;

---

Function Documentation

void AddOutlineFeatureToSet	(	FPOINT *	Start,
		FPOINT *	End,
		FEATURE_SET	FeatureSet
	)

---------------------------------------------------------------------------- Private Code ----------------------------------------------------------------------------

Definition at line 78 of file outfeat.cpp.

                                                    {
/*
 **     Parameters:
 **             Start           starting point of outline-feature
 **             End             ending point of outline-feature
 **             FeatureSet      set to add outline-feature to
 **     Globals: none
 **     Operation: This routine computes the midpoint between Start and
 **             End to obtain the x,y position of the outline-feature.  It
 **             also computes the direction from Start to End as the
 **             direction of the outline-feature and the distance from
 **             Start to End as the length of the outline-feature.
 **             This feature is then
 **             inserted into the next feature slot in FeatureSet.
 **     Return: none (results are placed in FeatureSet)
 **     Exceptions: none
 **     History: 11/13/90, DSJ, Created.
 */
  FEATURE Feature;

  Feature = NewFeature(&OutlineFeatDesc);
  Feature->Params[OutlineFeatDir] = NormalizedAngleFrom(Start, End, 1.0);
  Feature->Params[OutlineFeatX] = AverageOf(Start->x, End->x);
  Feature->Params[OutlineFeatY] = AverageOf(Start->y, End->y);
  Feature->Params[OutlineFeatLength] = DistanceBetween(*Start, *End);
  AddFeature(FeatureSet, Feature);

}                                /* AddOutlineFeatureToSet */

void ConvertToOutlineFeatures	(	MFOUTLINE	Outline,
		FEATURE_SET	FeatureSet
	)

Definition at line 111 of file outfeat.cpp.

                                                                         {
/*
 **     Parameters:
 **             Outline         outline to extract outline-features from
 **             FeatureSet      set of features to add outline-features to
 **     Globals: none
 **     Operation:
 **             This routine steps converts each section in the specified
 **             outline to a feature described by its x,y position, length
 **             and angle.
 **     Return: none (results are returned in FeatureSet)
 **     Exceptions: none
 **     History: 11/13/90, DSJ, Created.
 **                     5/24/91, DSJ, Added hidden edge capability.
 */
  MFOUTLINE Next;
  MFOUTLINE First;
  FPOINT FeatureStart;
  FPOINT FeatureEnd;

  if (DegenerateOutline (Outline))
    return;

  First = Outline;
  Next = First;
  do {
    FeatureStart = PointAt(Next)->Point;
    Next = NextPointAfter(Next);

    /* note that an edge is hidden if the ending point of the edge is
       marked as hidden.  This situation happens because the order of
       the outlines is reversed when they are converted from the old
       format.  In the old format, a hidden edge is marked by the
       starting point for that edge. */
    if (!PointAt(Next)->Hidden) {
      FeatureEnd = PointAt(Next)->Point;
      AddOutlineFeatureToSet(&FeatureStart, &FeatureEnd, FeatureSet);
    }
  }
  while (Next != First);
}                                /* ConvertToOutlineFeatures */

void NormalizeOutlineX

(

FEATURE_SET

FeatureSet

)

Definition at line 155 of file outfeat.cpp.

                                               {
/*
 **     Parameters:
 **             FeatureSet      outline-features to be normalized
 **     Globals: none
 **     Operation: This routine computes the weighted average x position
 **             over all of the outline-features in FeatureSet and then
 **             renormalizes the outline-features to force this average
 **             to be the x origin (i.e. x=0).
 **     Return: none (FeatureSet is changed)
 **     Exceptions: none
 **     History: 11/13/90, DSJ, Created.
 */
  int i;
  FEATURE Feature;
  FLOAT32 Length;
  FLOAT32 TotalX = 0.0;
  FLOAT32 TotalWeight = 0.0;
  FLOAT32 Origin;

  if (FeatureSet->NumFeatures <= 0)
    return;

  for (i = 0; i < FeatureSet->NumFeatures; i++) {
    Feature = FeatureSet->Features[i];
    Length = Feature->Params[OutlineFeatLength];
    TotalX += Feature->Params[OutlineFeatX] * Length;
    TotalWeight += Length;
  }
  Origin = TotalX / TotalWeight;

  for (i = 0; i < FeatureSet->NumFeatures; i++) {
    Feature = FeatureSet->Features[i];
    Feature->Params[OutlineFeatX] -= Origin;
  }
}                                /* NormalizeOutlineX */