Fct_Contour

Compute all the contours for a specific frame.

Syntax

int Fct_Contour_Create(

SliceO_Frame * frame

unsigned int mode,

unsigned short o_x,

unsigned short o_y

) ;

Parameters

frame

Pointer to the frame to compute.

mode

Control the formation of the contour loops.

	SHELL_MODE_LOOP	If the TAG values are on the border of the frame, the loop will be closed, otherwise it will stay open.
	SHELL_MODE_INSIDE	Place a border between a TAG and a TAG value that is greater than it.
	SHELL_MODE_OUTSIDE	Place a border betweena TAG value and a TAG value that is smaller than it.

o_x, o_y

Sub-sampling in horizontal and vertical direction. 1 mean no sub-sampling (each pixel is used).

Return value

This function return 0 if the function failed.

Remarks

Requirements

Header:

sliceO_include.hpp

Library:

sliceO_Structures.lib

Example

Computing the "Snake From TAG" in the "Snake" module. The snakes will be derived from a 2x2 sub-sampling contour.

// ----------------------------------------------------------------------------

// Snake_From_TAG

// Param: (void)

// Return: (int) NULL if error

// ----------------------------------------------------------------------------

int Snake_From_TAG( void )

{

Snake_Mode = 2 ;

unsigned short TAG_Nb = (unsigned short) Fct_Variable_Value( "$TAG_NB" ) ;

int *pts_tot = new int [TAG_Nb] ;

memset( (void *) pts_tot, NULL, TAG_Nb * sizeof(int) ) ;

// --- for each selected image ---

if ( ! Iterator_Init( ITERATOR_2, "Snake_From_TAG" ) )

return( 0 ) ;

// ================================================================

// --- no updates until we are done

// ================================================================

Fct_Update( UPDATE_DELAY_ON ) ;

SET_CURS_WAIT ;

while( SliceO_Frame *frame = (SliceO_Frame *) Iterator_Class( ITERATOR_2, CLASS_ID_FRAME, NULL, ITER_FLAG_SELECT ) ) {

// --- clear the present Snake values ---

for ( int i=0; i < Snake_Nb; i++ )

if ( Snake_List[i]->frame == frame )

Snake_Remove( Snake_List[i] ) ;

// --- compute a new contour with 2x2 oversampling ---

Fct_Contour_Create( frame, SHELL_MODE_LOOP | SHELL_MODE_BORDER, 2, 2 ) ;

// --- information stool ---

for ( unsigned char tag=1; tag < TAG_Nb; tag++ ) {

// --- Get the contour points for this tag and this frame ---

Point_2D *pts ;

int pts_nb = Fct_Contour_Get_Pts( frame, tag, &pts ) ;

if ( ! pts_nb )

continue ;

pts_tot[tag] += pts_nb ;

// --- now get the connectivity for these points ---

SliceO_Buffer *loop_pt ;

int loop_nb = Fct_Contour_Get_Loops( frame, tag, &loop_pt ) ;

for ( int j=0; j < loop_nb; j++ ) {

int loop_pts_nb = loop_pt[j].Size_Get() / sizeof(int) ;

int *loop_pts_id = (int *) loop_pt[j].Data_Get() ;

// --- we need a minimum of points on the contour ---

if ( loop_pts_nb <= MIN_NB_PTS )

continue ;

// --- create a new snake ---

Snakes *snake = new Snakes ;

snake->Create( frame, tag ) ;

// --- add the new points ---

snake->nb_points = loop_pts_nb ;

MALLOC( Snake_Points *, snake->point, loop_pts_nb, sizeof(Snake_Points) ) ;

for ( int i=0; i < loop_pts_nb; i++ ) {

int index = loop_pts_id[i] ;

// --- insert new point ---

snake->point[i].radius = DEFAULT_RADIUS ;

snake->point[i].fx = pts[index].x + 0.5f ;

snake->point[i].fy = pts[index].y + 0.5f ;

snake->point[i].flag = REPARAM | RESNAKE | REFILTER ;

}

snake->creation = 0 ;

snake->flag = REPARAM | RESNAKE | REFILTER ;

// --- compute the Bounding box ---

snake->Compute_Bounding_Box() ;

Snake_Add( snake ) ;

}

// --- reset the lists ---

Fct_Contour_Free( frame ) ;

}

Iterator_End( ITERATOR_2 ) ;

for ( unsigned char tag=1; tag < TAG_Nb; tag++ )

if ( pts_tot[tag] )

Error_Fct( hwnd, ERROR_CODE_REPORT, "\tTAG[\001%d\002]: \001%d \002points on contours", tag, pts_tot[tag] ) ;

delete [] pts_tot ;

// ================================================================

// --- now we can restart the updates ---

// ================================================================

Fct_Update( UPDATE_DELAY_OFF ) ;

RESET_CURS ;

// --- redraw the image ---

Fct_Redraw( REDRAW_DB_OPENGL ) ;

return( 1 ) ;

}