cv.h

Simple example of circle detection in OpenCV + C++Builder6.

CVAPI(void)  cvInitSubdivDelaunay2D( CvSubdiv2D* subdiv, CvRect rect );

/* Creates new subdivision */
CVAPI(CvSubdiv2D*)  cvCreateSubdiv2D( int subdiv_type, int header_size,
                                      int vtx_size, int quadedge_size,
                                      CvMemStorage* storage );

/************************* high-level subdivision functions ***************************/

/* Simplified Delaunay diagram creation */
CV_INLINE  CvSubdiv2D* cvCreateSubdivDelaunay2D( CvRect rect, CvMemStorage* storage )
{
    CvSubdiv2D* subdiv = cvCreateSubdiv2D( CV_SEQ_KIND_SUBDIV2D, sizeof(*subdiv),
                         sizeof(CvSubdiv2DPoint), sizeof(CvQuadEdge2D), storage );

    cvInitSubdivDelaunay2D( subdiv, rect );
    return subdiv;
}


/* Inserts new point to the Delaunay triangulation */
CVAPI(CvSubdiv2DPoint*)  cvSubdivDelaunay2DInsert( CvSubdiv2D* subdiv, CvPoint2D32f pt);

/* Locates a point within the Delaunay triangulation (finds the edge
   the point is left to or belongs to, or the triangulation point the given
   point coinsides with */
CVAPI(CvSubdiv2DPointLocation)  cvSubdiv2DLocate(
                               CvSubdiv2D* subdiv, CvPoint2D32f pt,
                               CvSubdiv2DEdge* edge,
                               CvSubdiv2DPoint** vertex CV_DEFAULT(NULL) );

/* Calculates Voronoi tesselation (i.e. coordinates of Voronoi points) */
CVAPI(void)  cvCalcSubdivVoronoi2D( CvSubdiv2D* subdiv );


/* Removes all Voronoi points from the tesselation */
CVAPI(void)  cvClearSubdivVoronoi2D( CvSubdiv2D* subdiv );


/* Finds the nearest to the given point vertex in subdivision. */
CVAPI(CvSubdiv2DPoint*) cvFindNearestPoint2D( CvSubdiv2D* subdiv, CvPoint2D32f pt );


/************ Basic quad-edge navigation and operations ************/

CV_INLINE  CvSubdiv2DEdge  cvSubdiv2DNextEdge( CvSubdiv2DEdge edge )
{
    return  CV_SUBDIV2D_NEXT_EDGE(edge);
}


CV_INLINE  CvSubdiv2DEdge  cvSubdiv2DRotateEdge( CvSubdiv2DEdge edge, int rotate )
{
    return  (edge & ~3) + ((edge + rotate) & 3);
}

CV_INLINE  CvSubdiv2DEdge  cvSubdiv2DSymEdge( CvSubdiv2DEdge edge )
{
    return edge ^ 2;
}

CV_INLINE  CvSubdiv2DEdge  cvSubdiv2DGetEdge( CvSubdiv2DEdge edge, CvNextEdgeType type )
{
    CvQuadEdge2D* e = (CvQuadEdge2D*)(edge & ~3);
    edge = e->next[(edge + (int)type) & 3];
    return  (edge & ~3) + ((edge + ((int)type >> 4)) & 3);
}


CV_INLINE  CvSubdiv2DPoint*  cvSubdiv2DEdgeOrg( CvSubdiv2DEdge edge )
{
    CvQuadEdge2D* e = (CvQuadEdge2D*)(edge & ~3);
    return (CvSubdiv2DPoint*)e->pt[edge & 3];
}


CV_INLINE  CvSubdiv2DPoint*  cvSubdiv2DEdgeDst( CvSubdiv2DEdge edge )
{
    CvQuadEdge2D* e = (CvQuadEdge2D*)(edge & ~3);
    return (CvSubdiv2DPoint*)e->pt[(edge + 2) & 3];
}


CV_INLINE  double  cvTriangleArea( CvPoint2D32f a, CvPoint2D32f b, CvPoint2D32f c )
{
    return (b.x - a.x) * (c.y - a.y) - (b.y - a.y) * (c.x - a.x);
}


/****************************************************************************************\
*                            Contour Processing and Shape Analysis                       *
\****************************************************************************************/

#define CV_POLY_APPROX_DP 0

/* Approximates a single polygonal curve (contour) or
   a tree of polygonal curves (contours) */
CVAPI(CvSeq*)  cvApproxPoly( const void* src_seq,
                             int header_size, CvMemStorage* storage,
                             int method, double parameter,
                             int parameter2 CV_DEFAULT(0));

#define CV_DOMINANT_IPAN 1

/* Finds high-curvature points of the contour */
CVAPI(CvSeq*) cvFindDominantPoints( CvSeq* contour, CvMemStorage* storage,
                                   int method CV_DEFAULT(CV_DOMINANT_IPAN),
                                   double parameter1 CV_DEFAULT(0),
                                   double parameter2 CV_DEFAULT(0),
                                   double parameter3 CV_DEFAULT(0),
                                   double parameter4 CV_DEFAULT(0));

/* Calculates perimeter of a contour or length of a part of contour */
CVAPI(double)  cvArcLength( const void* curve,
                            CvSlice slice CV_DEFAULT(CV_WHOLE_SEQ),
                            int is_closed CV_DEFAULT(-1));
#define cvContourPerimeter( contour ) cvArcLength( contour, CV_WHOLE_SEQ, 1 )

/* Calculates contour boundning rectangle (update=1) or
   just retrieves pre-calculated rectangle (update=0) */
CVAPI(CvRect)  cvBoundingRect( CvArr* points, int update CV_DEFAULT(0) );

/* Calculates area of a contour or contour segment */
CVAPI(double)  cvContourArea( const CvArr* contour,
                              CvSlice slice CV_DEFAULT(CV_WHOLE_SEQ));

/* Finds minimum area rotated rectangle bounding a set of points */
CVAPI(CvBox2D)  cvMinAreaRect2( const CvArr* points,
                                CvMemStorage* storage CV_DEFAULT(NULL));

/* Finds minimum enclosing circle for a set of points */
CVAPI(int)  cvMinEnclosingCircle( const CvArr* points,
                                  CvPoint2D32f* center, float* radius );

#define CV_CONTOURS_MATCH_I1  1
#define CV_CONTOURS_MATCH_I2  2
#define CV_CONTOURS_MATCH_I3  3

/* Compares two contours by matching their moments */
CVAPI(double)  cvMatchShapes( const void* object1, const void* object2,
                              int method, double parameter CV_DEFAULT(0));

/* Builds hierarhical representation of a contour */
CVAPI(CvContourTree*)  cvCreateContourTree( const CvSeq* contour,
                                            CvMemStorage* storage,
                                            double threshold );

/* Reconstruct (completelly or partially) contour a from contour tree */
CVAPI(CvSeq*)  cvContourFromContourTree( const CvContourTree* tree,
                                         CvMemStorage* storage,
                                         CvTermCriteria criteria );

/* Compares two contour trees */
#define  CV_CONTOUR_TREES_MATCH_I1  1

CVAPI(double)  cvMatchContourTrees( const CvContourTree* tree1,
                                    const CvContourTree* tree2,
                                    int method, double threshold );

/* Calculates histogram of a contour */
CVAPI(void)  cvCalcPGH( const CvSeq* contour, CvHistogram* hist );

#define CV_CLOCKWISE         1
#define CV_COUNTER_CLOCKWISE 2

/* Calculates exact convex hull of 2d point set */
CVAPI(CvSeq*) cvConvexHull2( const CvArr* input,
                             void* hull_storage CV_DEFAULT(NULL),
                             int orientation CV_DEFAULT(CV_CLOCKWISE),
                             int return_points CV_DEFAULT(0));

/* Checks whether the contour is convex or not (returns 1 if convex, 0 if not) */
CVAPI(int)  cvCheckContourConvexity( const CvArr* contour );

/* Finds convexity defects for the contour */
CVAPI(CvSeq*)  cvConvexityDefects( const CvArr* contour, const CvArr* convexhull,
                                   CvMemStorage* storage CV_DEFAULT(NULL));

/* Fits ellipse into a set of 2d points */
CVAPI(CvBox2D) cvFitEllipse2( const CvArr* points );

/* Finds minimum rectangle containing two given rectangles */
CVAPI(CvRect)  cvMaxRect( const CvRect* rect1, const CvRect* rect2 );

/* Finds coordinates of the box vertices */
CVAPI(void) cvBoxPoints( CvBox2D box, CvPoint2D32f pt[4] );

/* Initializes sequence header for a matrix (column or row vector) of points -
   a wrapper for cvMakeSeqHeaderForArray (it does not initialize bounding rectangle!!!) */
CVAPI(CvSeq*) cvPointSeqFromMat( int seq_kind, const CvArr* mat,
                                 CvContour* contour_header,
                                 CvSeqBlock* block );

/* Checks whether the point is inside polygon, outside, on an edge (at a vertex).
   Returns positive, negative or zero value, correspondingly.
   Optionally, measures a signed distance between
   the point and the nearest polygon edge (measure_dist=1) */
CVAPI(double) cvPointPolygonTest( const CvArr* contour,
                                  CvPoint2D32f pt, int measure_dist );

/****************************************************************************************\
*                                  Histogram functions                                   *
\****************************************************************************************/

/* Creates new histogram */
CVAPI(CvHistogram*)  cvCreateHist( int dims, int* sizes, int type,
                                   float** ranges CV_DEFAULT(NULL),
                                   int uniform CV_DEFAULT(1));

/* Assignes histogram bin ranges */
CVAPI(void)  cvSetHistBinRanges( CvHistogram* hist, float** ranges,
                                int uniform CV_DEFAULT(1));

/* Creates histogram header for array */
CVAPI(CvHistogram*)  cvMakeHistHeaderForArray(
                            int  dims, int* sizes, CvHistogram* hist,
                            float* data, float** ranges CV_DEFAULT(NULL),
                            int uniform CV_DEFAULT(1));

/* Releases histogram */
CVAPI(void)  cvReleaseHist( CvHistogram** hist );

/* Clears all the histogram bins */
CVAPI(void)  cvClearHist( CvHistogram* hist );

/* Finds indices and values of minimum and maximum histogram bins */
CVAPI(void)  cvGetMinMaxHistValue( const CvHistogram* hist,
                                   float* min_value, float* max_value,
                                   int* min_idx CV_DEFAULT(NULL),
                                   int* max_idx CV_DEFAULT(NULL));


/* Normalizes histogram by dividing all bins by sum of the bins, multiplied by <factor>.
   After that sum of histogram bins is equal to <factor> */
CVAPI(void)  cvNormalizeHist( CvHistogram* hist, double factor );


/* Clear all histogram bins that are below the threshold */
CVAPI(void)  cvThreshHist( CvHistogram* hist, double threshold );

#define CV_COMP_CORREL        0
#define CV_COMP_CHISQR        1
#define CV_COMP_INTERSECT     2
#define CV_COMP_BHATTACHARYYA 3

/* Compares two histogram */
CVAPI(double)  cvCompareHist( const CvHistogram* hist1,
                              const CvHistogram* hist2,
                              int method);

/* Copies one histogram to another. Destination histogram is created if
   the destination pointer is NULL */
CVAPI(void)  cvCopyHist( const CvHistogram* src, CvHistogram** dst );


/* Calculates bayesian probabilistic histograms
   (each or src and dst is an array of <number> histograms */
CVAPI(void)  cvCalcBayesianProb( CvHistogram** src, int number,
                                CvHistogram** dst);

/* Calculates array histogram */
CVAPI(void)  cvCalcArrHist( CvArr** arr, CvHistogram* hist,
                            int accumulate CV_DEFAULT(0),
                            const CvArr* mask CV_DEFAULT(NULL) );

CV_INLINE  void  cvCalcHist( IplImage** image, CvHistogram* hist,
                             int accumulate CV_DEFAULT(0),
                             const CvArr* mask CV_DEFAULT(NULL) )
{
    cvCalcArrHist( (CvArr**)image, hist, accumulate, mask );
}

/* Calculates back project */
CVAPI(void)  cvCalcArrBackProject( CvArr** image, CvArr* dst,
                                   const CvHistogram* hist );
#define  cvCalcBackProject(image, dst, hist) cvCalcArrBackProject((CvArr**)image, dst, hist)


/* Does some sort of template matching but compares histograms of
   template and each window location */
CVAPI(void)  cvCalcArrBackProjectPatch( CvArr** image, CvArr* dst, CvSize range,
                                        CvHistogram* hist, int method,
                                        double factor );
#define  cvCalcBackProjectPatch( image, dst, range, hist, method, factor ) \
     cvCalcArrBackProjectPatch( (CvArr**)image, dst, range, hist, method, factor )


/* calculates probabilistic density (divides one histogram by another) */
CVAPI(void)  cvCalcProbDensity( const CvHistogram* hist1, const CvHistogram* hist2,
                                CvHistogram* dst_hist, double scale CV_DEFAULT(255) );

/* equalizes histogram of 8-bit single-channel image */
CVAPI(void)  cvEqualizeHist( const CvArr* src, CvArr* dst );


#define  CV_VALUE  1
#define  CV_ARRAY  2
/* Updates active contour in order to minimize its cummulative
   (internal and external) energy. */
CVAPI(void)  cvSnakeImage( const IplImage* image, CvPoint* points,
                           int  length, float* alpha,
                           float* beta, float* gamma,
                           int coeff_usage, CvSize  win,