cxcore.h

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

#define CV_FRONT 1
#define CV_BACK 0
/* Adds several new elements to the end of sequence */
CVAPI(void)  cvSeqPushMulti( CvSeq* seq, void* elements,
                             int count, int in_front CV_DEFAULT(0) );

/* Removes several elements from the end of sequence and optionally saves them */
CVAPI(void)  cvSeqPopMulti( CvSeq* seq, void* elements,
                            int count, int in_front CV_DEFAULT(0) );

/* Inserts a new element in the middle of sequence.
   cvSeqInsert(seq,0,elem) == cvSeqPushFront(seq,elem) */
CVAPI(char*)  cvSeqInsert( CvSeq* seq, int before_index,
                           void* element CV_DEFAULT(NULL));

/* Removes specified sequence element */
CVAPI(void)  cvSeqRemove( CvSeq* seq, int index );


/* Removes all the elements from the sequence. The freed memory
   can be reused later only by the same sequence unless cvClearMemStorage
   or cvRestoreMemStoragePos is called */
CVAPI(void)  cvClearSeq( CvSeq* seq );


/* Retrives pointer to specified sequence element.
   Negative indices are supported and mean counting from the end
   (e.g -1 means the last sequence element) */
CVAPI(char*)  cvGetSeqElem( const CvSeq* seq, int index );

/* Calculates index of the specified sequence element.
   Returns -1 if element does not belong to the sequence */
CVAPI(int)  cvSeqElemIdx( const CvSeq* seq, const void* element,
                         CvSeqBlock** block CV_DEFAULT(NULL) );

/* Initializes sequence writer. The new elements will be added to the end of sequence */
CVAPI(void)  cvStartAppendToSeq( CvSeq* seq, CvSeqWriter* writer );


/* Combination of cvCreateSeq and cvStartAppendToSeq */
CVAPI(void)  cvStartWriteSeq( int seq_flags, int header_size,
                              int elem_size, CvMemStorage* storage,
                              CvSeqWriter* writer );

/* Closes sequence writer, updates sequence header and returns pointer
   to the resultant sequence
   (which may be useful if the sequence was created using cvStartWriteSeq))
*/
CVAPI(CvSeq*)  cvEndWriteSeq( CvSeqWriter* writer );


/* Updates sequence header. May be useful to get access to some of previously
   written elements via cvGetSeqElem or sequence reader */
CVAPI(void)   cvFlushSeqWriter( CvSeqWriter* writer );


/* Initializes sequence reader.
   The sequence can be read in forward or backward direction */
CVAPI(void) cvStartReadSeq( const CvSeq* seq, CvSeqReader* reader,
                           int reverse CV_DEFAULT(0) );


/* Returns current sequence reader position (currently observed sequence element) */
CVAPI(int)  cvGetSeqReaderPos( CvSeqReader* reader );


/* Changes sequence reader position. It may seek to an absolute or
   to relative to the current position */
CVAPI(void)   cvSetSeqReaderPos( CvSeqReader* reader, int index,
                                 int is_relative CV_DEFAULT(0));

/* Copies sequence content to a continuous piece of memory */
CVAPI(void*)  cvCvtSeqToArray( const CvSeq* seq, void* elements,
                               CvSlice slice CV_DEFAULT(CV_WHOLE_SEQ) );

/* Creates sequence header for array.
   After that all the operations on sequences that do not alter the content
   can be applied to the resultant sequence */
CVAPI(CvSeq*) cvMakeSeqHeaderForArray( int seq_type, int header_size,
                                       int elem_size, void* elements, int total,
                                       CvSeq* seq, CvSeqBlock* block );

/* Extracts sequence slice (with or without copying sequence elements) */
CVAPI(CvSeq*) cvSeqSlice( const CvSeq* seq, CvSlice slice,
                         CvMemStorage* storage CV_DEFAULT(NULL),
                         int copy_data CV_DEFAULT(0));

CV_INLINE CvSeq* cvCloneSeq( const CvSeq* seq, CvMemStorage* storage CV_DEFAULT(NULL));
CV_INLINE CvSeq* cvCloneSeq( const CvSeq* seq, CvMemStorage* storage )
{
    return cvSeqSlice( seq, CV_WHOLE_SEQ, storage, 1 );
}

/* Removes sequence slice */
CVAPI(void)  cvSeqRemoveSlice( CvSeq* seq, CvSlice slice );

/* Inserts a sequence or array into another sequence */
CVAPI(void)  cvSeqInsertSlice( CvSeq* seq, int before_index, const CvArr* from_arr );

/* a < b ? -1 : a > b ? 1 : 0 */
typedef int (CV_CDECL* CvCmpFunc)(const void* a, const void* b, void* userdata );

/* Sorts sequence in-place given element comparison function */
CVAPI(void) cvSeqSort( CvSeq* seq, CvCmpFunc func, void* userdata CV_DEFAULT(NULL) );

/* Finds element in a [sorted] sequence */
CVAPI(char*) cvSeqSearch( CvSeq* seq, const void* elem, CvCmpFunc func,
                          int is_sorted, int* elem_idx,
                          void* userdata CV_DEFAULT(NULL) );

/* Reverses order of sequence elements in-place */
CVAPI(void) cvSeqInvert( CvSeq* seq );

/* Splits sequence into one or more equivalence classes using the specified criteria */
CVAPI(int)  cvSeqPartition( const CvSeq* seq, CvMemStorage* storage,
                            CvSeq** labels, CvCmpFunc is_equal, void* userdata );

/************ Internal sequence functions ************/
CVAPI(void)  cvChangeSeqBlock( CvSeqReader* reader, int direction );
CVAPI(void)  cvCreateSeqBlock( CvSeqWriter* writer );


/* Creates a new set */
CVAPI(CvSet*)  cvCreateSet( int set_flags, int header_size,
                            int elem_size, CvMemStorage* storage );

/* Adds new element to the set and returns pointer to it */
CVAPI(int)  cvSetAdd( CvSet* set_header, CvSetElem* elem CV_DEFAULT(NULL),
                      CvSetElem** inserted_elem CV_DEFAULT(NULL) );

/* Fast variant of cvSetAdd */
CV_INLINE  CvSetElem* cvSetNew( CvSet* set_header );
CV_INLINE  CvSetElem* cvSetNew( CvSet* set_header )
{
    CvSetElem* elem = set_header->free_elems;
    if( elem )
    {
        set_header->free_elems = elem->next_free;
        elem->flags = elem->flags & CV_SET_ELEM_IDX_MASK;
        set_header->active_count++;
    }
    else
        cvSetAdd( set_header, NULL, (CvSetElem**)&elem );
    return elem;
}

/* Removes set element given its pointer */
CV_INLINE  void cvSetRemoveByPtr( CvSet* set_header, void* elem );
CV_INLINE  void cvSetRemoveByPtr( CvSet* set_header, void* elem )
{
    CvSetElem* _elem = (CvSetElem*)elem;
    assert( _elem->flags >= 0 /*&& (elem->flags & CV_SET_ELEM_IDX_MASK) < set_header->total*/ );
    _elem->next_free = set_header->free_elems;
    _elem->flags = (_elem->flags & CV_SET_ELEM_IDX_MASK) | CV_SET_ELEM_FREE_FLAG;
    set_header->free_elems = _elem;
    set_header->active_count--;
}

/* Removes element from the set by its index  */
CVAPI(void)   cvSetRemove( CvSet* set_header, int index );

/* Returns a set element by index. If the element doesn't belong to the set,
   NULL is returned */
CV_INLINE CvSetElem* cvGetSetElem( const CvSet* set_header, int index );
CV_INLINE CvSetElem* cvGetSetElem( const CvSet* set_header, int index )
{
    CvSetElem* elem = (CvSetElem*)cvGetSeqElem( (CvSeq*)set_header, index );
    return elem && CV_IS_SET_ELEM( elem ) ? elem : 0;
}

/* Removes all the elements from the set */
CVAPI(void)  cvClearSet( CvSet* set_header );

/* Creates new graph */
CVAPI(CvGraph*)  cvCreateGraph( int graph_flags, int header_size,
                                int vtx_size, int edge_size,
                                CvMemStorage* storage );

/* Adds new vertex to the graph */
CVAPI(int)  cvGraphAddVtx( CvGraph* graph, const CvGraphVtx* vtx CV_DEFAULT(NULL),
                           CvGraphVtx** inserted_vtx CV_DEFAULT(NULL) );


/* Removes vertex from the graph together with all incident edges */
CVAPI(int)  cvGraphRemoveVtx( CvGraph* graph, int index );
CVAPI(int)  cvGraphRemoveVtxByPtr( CvGraph* graph, CvGraphVtx* vtx );


/* Link two vertices specifed by indices or pointers if they
   are not connected or return pointer to already existing edge
   connecting the vertices.
   Functions return 1 if a new edge was created, 0 otherwise */
CVAPI(int)  cvGraphAddEdge( CvGraph* graph,
                            int start_idx, int end_idx,
                            const CvGraphEdge* edge CV_DEFAULT(NULL),
                            CvGraphEdge** inserted_edge CV_DEFAULT(NULL) );

CVAPI(int)  cvGraphAddEdgeByPtr( CvGraph* graph,
                               CvGraphVtx* start_vtx, CvGraphVtx* end_vtx,
                               const CvGraphEdge* edge CV_DEFAULT(NULL),
                               CvGraphEdge** inserted_edge CV_DEFAULT(NULL) );

/* Remove edge connecting two vertices */
CVAPI(void)  cvGraphRemoveEdge( CvGraph* graph, int start_idx, int end_idx );
CVAPI(void)  cvGraphRemoveEdgeByPtr( CvGraph* graph, CvGraphVtx* start_vtx,
                                     CvGraphVtx* end_vtx );

/* Find edge connecting two vertices */
CVAPI(CvGraphEdge*)  cvFindGraphEdge( const CvGraph* graph, int start_idx, int end_idx );
CVAPI(CvGraphEdge*)  cvFindGraphEdgeByPtr( const CvGraph* graph,
                                           const CvGraphVtx* start_vtx,
                                           const CvGraphVtx* end_vtx );
#define cvGraphFindEdge cvFindGraphEdge
#define cvGraphFindEdgeByPtr cvFindGraphEdgeByPtr

/* Remove all vertices and edges from the graph */
CVAPI(void)  cvClearGraph( CvGraph* graph );


/* Count number of edges incident to the vertex */
CVAPI(int)  cvGraphVtxDegree( const CvGraph* graph, int vtx_idx );
CVAPI(int)  cvGraphVtxDegreeByPtr( const CvGraph* graph, const CvGraphVtx* vtx );


/* Retrieves graph vertex by given index */
#define cvGetGraphVtx( graph, idx ) (CvGraphVtx*)cvGetSetElem((CvSet*)(graph), (idx))

/* Retrieves index of a graph vertex given its pointer */
#define cvGraphVtxIdx( graph, vtx ) ((vtx)->flags & CV_SET_ELEM_IDX_MASK)

/* Retrieves index of a graph edge given its pointer */
#define cvGraphEdgeIdx( graph, edge ) ((edge)->flags & CV_SET_ELEM_IDX_MASK)

#define cvGraphGetVtxCount( graph ) ((graph)->active_count)
#define cvGraphGetEdgeCount( graph ) ((graph)->edges->active_count)

#define  CV_GRAPH_VERTEX        1
#define  CV_GRAPH_TREE_EDGE     2
#define  CV_GRAPH_BACK_EDGE     4
#define  CV_GRAPH_FORWARD_EDGE  8
#define  CV_GRAPH_CROSS_EDGE    16
#define  CV_GRAPH_ANY_EDGE      30
#define  CV_GRAPH_NEW_TREE      32
#define  CV_GRAPH_BACKTRACKING  64
#define  CV_GRAPH_OVER          -1

#define  CV_GRAPH_ALL_ITEMS    -1

/* flags for graph vertices and edges */
#define  CV_GRAPH_ITEM_VISITED_FLAG  (1 << 30)
#define  CV_IS_GRAPH_VERTEX_VISITED(vtx) \
    (((CvGraphVtx*)(vtx))->flags & CV_GRAPH_ITEM_VISITED_FLAG)
#define  CV_IS_GRAPH_EDGE_VISITED(edge) \
    (((CvGraphEdge*)(edge))->flags & CV_GRAPH_ITEM_VISITED_FLAG)
#define  CV_GRAPH_SEARCH_TREE_NODE_FLAG   (1 << 29)
#define  CV_GRAPH_FORWARD_EDGE_FLAG       (1 << 28)

typedef struct CvGraphScanner
{
    CvGraphVtx* vtx;       /* current graph vertex (or current edge origin) */
    CvGraphVtx* dst;       /* current graph edge destination vertex */
    CvGraphEdge* edge;     /* current edge */

    CvGraph* graph;        /* the graph */
    CvSeq*   stack;        /* the graph vertex stack */
    int      index;        /* the lower bound of certainly visited vertices */
    int      mask;         /* event mask */
}
CvGraphScanner;

/* Creates new graph scanner. */
CVAPI(CvGraphScanner*)  cvCreateGraphScanner( CvGraph* graph,
                                             CvGraphVtx* vtx CV_DEFAULT(NULL),
                                             int mask CV_DEFAULT(CV_GRAPH_ALL_ITEMS));

/* Releases graph scanner. */
CVAPI(void) cvReleaseGraphScanner( CvGraphScanner** scanner );

/* Get next graph element */
CVAPI(int)  cvNextGraphItem( CvGraphScanner* scanner );

/* Creates a copy of graph */
CVAPI(CvGraph*) cvCloneGraph( const CvGraph* graph, CvMemStorage* storage );

/****************************************************************************************\
*                                     Drawing                                            *
\****************************************************************************************/

/****************************************************************************************\
*       Drawing functions work with images/matrices of arbitrary type.                   *
*       For color images the channel order is BGR[A]                                     *
*       Antialiasing is supported only for 8-bit image now.                              *
*       All the functions include parameter color that means rgb value (that may be      *
*       constructed with CV_RGB macro) for color images and brightness                   *
*       for grayscale images.                                                            *
*       If a drawn figure is partially or completely outside the image, it is clipped.   *
\****************************************************************************************/

#define CV_RGB( r, g, b )  cvScalar( (b), (g), (r), 0 )
#define CV_FILLED -1