cxcore.h

Simple ellipse fitting example on C++Builder6 + OpenCV1.0.

#define CV_AA 16

/* Draws 4-connected, 8-connected or antialiased line segment connecting two points */
CVAPI(void)  cvLine( CvArr* img, CvPoint pt1, CvPoint pt2,
                     CvScalar color, int thickness CV_DEFAULT(1),
                     int line_type CV_DEFAULT(8), int shift CV_DEFAULT(0) );

/* Draws a rectangle given two opposite corners of the rectangle (pt1 & pt2),
   if thickness<0 (e.g. thickness == CV_FILLED), the filled box is drawn */
CVAPI(void)  cvRectangle( CvArr* img, CvPoint pt1, CvPoint pt2,
                          CvScalar color, int thickness CV_DEFAULT(1),
                          int line_type CV_DEFAULT(8),
                          int shift CV_DEFAULT(0));

/* Draws a circle with specified center and radius.
   Thickness works in the same way as with cvRectangle */
CVAPI(void)  cvCircle( CvArr* img, CvPoint center, int radius,
                       CvScalar color, int thickness CV_DEFAULT(1),
                       int line_type CV_DEFAULT(8), int shift CV_DEFAULT(0));

/* Draws ellipse outline, filled ellipse, elliptic arc or filled elliptic sector,
   depending on <thickness>, <start_angle> and <end_angle> parameters. The resultant figure
   is rotated by <angle>. All the angles are in degrees */
CVAPI(void)  cvEllipse( CvArr* img, CvPoint center, CvSize axes,
                        double angle, double start_angle, double end_angle,
                        CvScalar color, int thickness CV_DEFAULT(1),
                        int line_type CV_DEFAULT(8), int shift CV_DEFAULT(0));

CV_INLINE  void  cvEllipseBox( CvArr* img, CvBox2D box, CvScalar color,
                               int thickness CV_DEFAULT(1),
                               int line_type CV_DEFAULT(8), int shift CV_DEFAULT(0) );
CV_INLINE  void  cvEllipseBox( CvArr* img, CvBox2D box, CvScalar color,
                               int thickness, int line_type, int shift )
{
    CvSize axes;
    axes.width = cvRound(box.size.height*0.5);
    axes.height = cvRound(box.size.width*0.5);
    
    cvEllipse( img, cvPointFrom32f( box.center ), axes, box.angle*180/CV_PI,
               0, 360, color, thickness, line_type, shift );
}

/* Fills convex or monotonous polygon. */
CVAPI(void)  cvFillConvexPoly( CvArr* img, CvPoint* pts, int npts, CvScalar color,
                               int line_type CV_DEFAULT(8), int shift CV_DEFAULT(0));

/* Fills an area bounded by one or more arbitrary polygons */
CVAPI(void)  cvFillPoly( CvArr* img, CvPoint** pts, int* npts, int contours, CvScalar color,
                         int line_type CV_DEFAULT(8), int shift CV_DEFAULT(0) );

/* Draws one or more polygonal curves */
CVAPI(void)  cvPolyLine( CvArr* img, CvPoint** pts, int* npts, int contours,
                         int is_closed, CvScalar color, int thickness CV_DEFAULT(1),
                         int line_type CV_DEFAULT(8), int shift CV_DEFAULT(0) );

/* basic font types */
#define CV_FONT_HERSHEY_SIMPLEX         0
#define CV_FONT_HERSHEY_PLAIN           1
#define CV_FONT_HERSHEY_DUPLEX          2
#define CV_FONT_HERSHEY_COMPLEX         3 
#define CV_FONT_HERSHEY_TRIPLEX         4
#define CV_FONT_HERSHEY_COMPLEX_SMALL   5
#define CV_FONT_HERSHEY_SCRIPT_SIMPLEX  6
#define CV_FONT_HERSHEY_SCRIPT_COMPLEX  7

/* font flags */
#define CV_FONT_ITALIC                 16  

#define CV_FONT_VECTOR0    CV_FONT_HERSHEY_SIMPLEX

/* Font structure */
typedef struct CvFont
{
    int         font_face; /* =CV_FONT_* */
    const int*  ascii; /* font data and metrics */
    const int*  greek;
    const int*  cyrillic;
    float       hscale, vscale;
    float       shear; /* slope coefficient: 0 - normal, >0 - italic */
    int         thickness; /* letters thickness */
    float       dx; /* horizontal interval between letters */
    int         line_type;
}
CvFont;

/* Initializes font structure used further in cvPutText */
CVAPI(void)  cvInitFont( CvFont* font, int font_face,
                         double hscale, double vscale,
                         double shear CV_DEFAULT(0),
                         int thickness CV_DEFAULT(1),
                         int line_type CV_DEFAULT(8));

/* Renders text stroke with specified font and color at specified location.
   CvFont should be initialized with cvInitFont */
CVAPI(void)  cvPutText( CvArr* img, const char* text, CvPoint org,
                        const CvFont* font, CvScalar color );

/* Calculates bounding box of text stroke (useful for alignment) */
CVAPI(void)  cvGetTextSize( const char* text_string, const CvFont* font,
                            CvSize* text_size, int* baseline );

/* Unpacks color value, if arrtype is CV_8UC?, <color> is treated as
   packed color value, otherwise the first channels (depending on arrtype)
   of destination scalar are set to the same value = <color> */
CVAPI(CvScalar)  cvColorToScalar( double packed_color, int arrtype );

/* Draws contour outlines or filled interiors on the image */
CVAPI(void)  cvDrawContours( CvArr *img, CvSeq* contour,
                            CvScalar external_color, CvScalar hole_color,
                            int max_level, int thickness CV_DEFAULT(1),
                            int line_type CV_DEFAULT(8));

/* Does look-up transformation. Elements of the source array
   (that should be 8uC1 or 8sC1) are used as indexes in lutarr 256-element table */
CVAPI(void) cvLUT( const CvArr* src, CvArr* dst, const CvArr* lut );


/******************* Iteration through the sequence tree *****************/
typedef struct CvTreeNodeIterator
{
    const void* node;
    int level;
    int max_level;
}
CvTreeNodeIterator;

CVAPI(void) cvInitTreeNodeIterator( CvTreeNodeIterator* tree_iterator,
                                   const void* first, int max_level );
CVAPI(void*) cvNextTreeNode( CvTreeNodeIterator* tree_iterator );
CVAPI(void*) cvPrevTreeNode( CvTreeNodeIterator* tree_iterator );

/* Inserts sequence into tree with specified "parent" sequence.
   If parent is equal to frame (e.g. the most external contour),
   then added contour will have null pointer to parent. */
CVAPI(void) cvInsertNodeIntoTree( void* node, void* parent, void* frame );

/* Removes contour from tree (together with the contour children). */
CVAPI(void) cvRemoveNodeFromTree( void* node, void* frame );

/* Gathers pointers to all the sequences,
   accessible from the <first>, to the single sequence */
CVAPI(CvSeq*) cvTreeToNodeSeq( const void* first, int header_size,
                              CvMemStorage* storage );

/* The function implements the K-means algorithm for clustering an array of sample
   vectors in a specified number of classes */
CVAPI(void)  cvKMeans2( const CvArr* samples, int cluster_count,
                        CvArr* labels, CvTermCriteria termcrit );

/****************************************************************************************\
*                                    System functions                                    *
\****************************************************************************************/

/* Add the function pointers table with associated information to the IPP primitives list */
CVAPI(int)  cvRegisterModule( const CvModuleInfo* module_info );

/* Loads optimized functions from IPP, MKL etc. or switches back to pure C code */
CVAPI(int)  cvUseOptimized( int on_off );

/* Retrieves information about the registered modules and loaded optimized plugins */
CVAPI(void)  cvGetModuleInfo( const char* module_name,
                              const char** version,
                              const char** loaded_addon_plugins );

/* Get current OpenCV error status */
CVAPI(int) cvGetErrStatus( void );

/* Sets error status silently */
CVAPI(void) cvSetErrStatus( int status );

#define CV_ErrModeLeaf     0   /* Print error and exit program */
#define CV_ErrModeParent   1   /* Print error and continue */
#define CV_ErrModeSilent   2   /* Don't print and continue */

/* Retrives current error processing mode */
CVAPI(int)  cvGetErrMode( void );

/* Sets error processing mode, returns previously used mode */
CVAPI(int) cvSetErrMode( int mode );

/* Sets error status and performs some additonal actions (displaying message box,
   writing message to stderr, terminating application etc.)
   depending on the current error mode */
CVAPI(void) cvError( int status, const char* func_name,
                    const char* err_msg, const char* file_name, int line );

/* Retrieves textual description of the error given its code */
CVAPI(const char*) cvErrorStr( int status );

/* Retrieves detailed information about the last error occured */
CVAPI(int) cvGetErrInfo( const char** errcode_desc, const char** description,
                        const char** filename, int* line );

/* Maps IPP error codes to the counterparts from OpenCV */
CVAPI(int) cvErrorFromIppStatus( int ipp_status );

typedef int (CV_CDECL *CvErrorCallback)( int status, const char* func_name,
                    const char* err_msg, const char* file_name, int line, void* userdata );

/* Assigns a new error-handling function */
CVAPI(CvErrorCallback) cvRedirectError( CvErrorCallback error_handler,
                                       void* userdata CV_DEFAULT(NULL),
                                       void** prev_userdata CV_DEFAULT(NULL) );

/*
    Output to:
        cvNulDevReport - nothing
        cvStdErrReport - console(fprintf(stderr,...))
        cvGuiBoxReport - MessageBox(WIN32)
*/
CVAPI(int) cvNulDevReport( int status, const char* func_name, const char* err_msg,
                          const char* file_name, int line, void* userdata );

CVAPI(int) cvStdErrReport( int status, const char* func_name, const char* err_msg,
                          const char* file_name, int line, void* userdata );

CVAPI(int) cvGuiBoxReport( int status, const char* func_name, const char* err_msg,
                          const char* file_name, int line, void* userdata );

typedef void* (CV_CDECL *CvAllocFunc)(size_t size, void* userdata);
typedef int (CV_CDECL *CvFreeFunc)(void* pptr, void* userdata);

/* Set user-defined memory managment functions (substitutors for malloc and free) that
   will be called by cvAlloc, cvFree and higher-level functions (e.g. cvCreateImage) */
CVAPI(void) cvSetMemoryManager( CvAllocFunc alloc_func CV_DEFAULT(NULL),
                               CvFreeFunc free_func CV_DEFAULT(NULL),
                               void* userdata CV_DEFAULT(NULL));


typedef IplImage* (CV_STDCALL* Cv_iplCreateImageHeader)
                            (int,int,int,char*,char*,int,int,int,int,int,
                            IplROI*,IplImage*,void*,IplTileInfo*);
typedef void (CV_STDCALL* Cv_iplAllocateImageData)(IplImage*,int,int);
typedef void (CV_STDCALL* Cv_iplDeallocate)(IplImage*,int);
typedef IplROI* (CV_STDCALL* Cv_iplCreateROI)(int,int,int,int,int);
typedef IplImage* (CV_STDCALL* Cv_iplCloneImage)(const IplImage*);

/* Makes OpenCV use IPL functions for IplImage allocation/deallocation */
CVAPI(void) cvSetIPLAllocators( Cv_iplCreateImageHeader create_header,
                               Cv_iplAllocateImageData allocate_data,
                               Cv_iplDeallocate deallocate,
                               Cv_iplCreateROI create_roi,
                               Cv_iplCloneImage clone_image );

#define CV_TURN_ON_IPL_COMPATIBILITY()                                  \
    cvSetIPLAllocators( iplCreateImageHeader, iplAllocateImage,         \
                        iplDeallocate, iplCreateROI, iplCloneImage )

/****************************************************************************************\
*                                    Data Persistence                                    *
\****************************************************************************************/

/********************************** High-level functions ********************************/

/* opens existing or creates new file storage */
CVAPI(CvFileStorage*)  cvOpenFileStorage( const char* filename,
                                          CvMemStorage* memstorage,
                                          int flags );

/* closes file storage and deallocates buffers */
CVAPI(void) cvReleaseFileStorage( CvFileStorage** fs );

/* returns attribute value or 0 (NULL) if there is no such attribute */
CVAPI(const char*) cvAttrValue( const CvAttrList* attr, const char* attr_name );

/* starts writing compound structure (map or sequence) */
CVAPI(void) cvStartWriteStruct( CvFileStorage* fs, const char* name,
                                int struct_flags, const char* type_name CV_DEFAULT(NULL),
                                CvAttrList attributes CV_DEFAULT(cvAttrList()));

/* finishes writing compound structure */
CVAPI(void) cvEndWriteStruct( CvFileStorage* fs );

/* writes an integer */
CVAPI(void) cvWriteInt( CvFileStorage* fs, const char* name, int value );

/* writes a floating-point number */
CVAPI(void) cvWriteReal( CvFileStorage* fs, const char* name, double value );

/* writes a string */
CVAPI(void) cvWriteString( CvFileStorage* fs, const char* name,
                           const char* str, int quote CV_DEFAULT(0) );

/* writes a comment */
CVAPI(void) cvWriteComment( CvFileStorage* fs, const char* comment,
                            int eol_comment );

/* writes instance of a standard type (matrix, image, sequence, graph etc.)
   or user-defined type */
CVAPI(void) cvWrite( CvFileStorage* fs, const char* name, const void* ptr,
                         CvAttrList attributes CV_DEFAULT(cvAttrList()));

/* starts the next stream */
CVAPI(void) cvStartNextStream( CvFileStorage* fs );

/* helper function: writes multiple integer or floating-point numbers */
CVAPI(void) cvWriteRawData( CvFileStorage* fs, const void* src,
                                int len, const char* dt );

/* returns the hash entry corresponding to the specified literal key string or 0
   if there is no such a key in the storage */
CVAPI(CvStringHashNode*) cvGetHashedKey( CvFileStorage* fs, const char* name,