下面是OPENCV B4.0 附带的 FLOOD FILL 算法的源代码样例，可以实现简单的彩色图像分割。
#ifdef _CH_
#pragma package <opencv>
#endif
#ifndef _EiC
#include "cv.h"
#include "highgui.h"
#include <stdio.h>
#include <stdlib.h>
#endif
IplImage* color_img0;
IplImage* mask;
IplImage* color_img;
IplImage* gray_img0 = NULL;
IplImage* gray_img = NULL;
int ffill_case = 1;
int lo_diff = 20, up_diff = 20;
int connectivity = 4;
int is_color = 1;
int is_mask = 0;
int new_mask_val = 255;
void on_mouse( int event, int x, int y, int flags )
{
if( !color_img )
return;
switch( event )
{
case CV_EVENT_LBUTTONDOWN:
{
CvPoint seed = cvPoint(x,y);
int lo = ffill_case == 0 ? 0 : lo_diff;
int up = ffill_case == 0 ? 0 : up_diff;
int flags = connectivity + (new_mask_val << 8) +
(ffill_case == 1 ? CV_FLOODFILL_FIXED_RANGE : 0);
int b = rand() & 255, g = rand() & 255, r = rand() & 255;
CvConnectedComp comp;
if( is_mask )
cvThreshold( mask, mask, 1, 128, CV_THRESH_BINARY );
if( is_color )
{
CvScalar color = CV_RGB( r, g, b );
cvFloodFill( color_img, seed, color, CV_RGB( lo, lo, lo ),
CV_RGB( up, up, up ), &comp, flags, is_mask ? mask : NULL );
cvShowImage( "image", color_img );
}
else
{
CvScalar brightness = cvRealScalar((r*2 + g*7 + b + 5)/10);
cvFloodFill( gray_img, seed, brightness, cvRealScalar(lo),
cvRealScalar(up), &comp, flags, is_mask ? mask : NULL );
cvShowImage( "image", gray_img );
}
printf("%g pixels were repainted\n", comp.area );
if( is_mask )
cvShowImage( "mask", mask );
}
break;
}
}
int main( int argc, char** argv )
{
char* filename = argc >= 2 ? argv[1] : (char*)"fruits.jpg";
if( (color_img0 = cvLoadImage(filename,1)) == 0 )
return 0;
printf( "Hot keys: \n"
"\tESC - quit the program\n"
"\tc - switch color/grayscale mode\n"
"\tm - switch mask mode\n"
"\tr - restore the original image\n"
"\ts - use null-range floodfill\n"
"\tf - use gradient floodfill with fixed(absolute) range\n"
"\tg - use gradient floodfill with floating(relative) range\n"
"\t4 - use 4-connectivity mode\n"
"\t8 - use 8-connectivity mode\n" );
color_img = cvCloneImage( color_img0 );
gray_img0 = cvCreateImage( cvSize(color_img->width, color_img->height), 8, 1 );
cvCvtColor( color_img, gray_img0, CV_BGR2GRAY );
gray_img = cvCloneImage( gray_img0 );
mask = cvCreateImage( cvSize(color_img->width + 2, color_img->height + 2), 8, 1 );
cvNamedWindow( "image", 0 );
cvCreateTrackbar( "lo_diff", "image", &lo_diff, 255, NULL );
cvCreateTrackbar( "up_diff", "image", &up_diff, 255, NULL );
cvSetMouseCallback( "image", on_mouse );
for(;;)
{
int c;
if( is_color )
cvShowImage( "image", color_img );
else
cvShowImage( "image", gray_img );
c = cvWaitKey(0);
switch( c )
{
case '\x1b':
printf("Exiting ...\n");
goto exit_main;
case 'c':
if( is_color )
{
printf("Grayscale mode is set\n");
cvCvtColor( color_img, gray_img, CV_BGR2GRAY );
is_color = 0;
}
else
{
printf("Color mode is set\n");
cvCopy( color_img0, color_img, NULL );
cvZero( mask );
is_color = 1;
}
break;
case 'm':
if( is_mask )
{
cvDestroyWindow( "mask" );
is_mask = 0;
}
else
{
cvNamedWindow( "mask", 0 );
cvZero( mask );
cvShowImage( "mask", mask );
is_mask = 1;
}
break;
case 'r':
printf("Original image is restored\n");
cvCopy( color_img0, color_img, NULL );
cvCopy( gray_img0, gray_img, NULL );
cvZero( mask );
break;
case 's':
printf("Simple floodfill mode is set\n");
ffill_case = 0;
break;
case 'f':
printf("Fixed Range floodfill mode is set\n");
ffill_case = 1;
break;
case 'g':
printf("Gradient (floating range) floodfill mode is set\n");
ffill_case = 2;
break;
case '4':
printf("4-connectivity mode is set\n");
connectivity = 4;
break;
case '8':
printf("8-connectivity mode is set\n");
connectivity = 8;
break;
}
}
exit_main:
cvDestroyWindow( "test" );
cvReleaseImage( &gray_img );
cvReleaseImage( &gray_img0 );
cvReleaseImage( &color_img );
cvReleaseImage( &color_img0 );
cvReleaseImage( &mask );
return 1;
}
#ifdef _EiC
main(1,"ffilldemo.c");
#endif
