【OpenCV】使用floodfill（）实现PhotoShop魔棒功能

在OpenCV中看到一个很有意思的函数：floodfill（）使用给定颜色填充一个联通的区域C++: int floodFill（InputOutputArray image, Point seedPoint, 
Scalar newVal, Rect* rect=0, Scalar loDiff=Scalar（）, 
Scalar upDiff=Scalar（）, int flags=4 ）一个简单的例子：#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"#include <iostream>using namespace cv;
using namespace std;
//floodfill（）
//Fills a connected component with the given color.static void help（）
{
cout << " This program demonstrated the floodFill（） function "
"Call: "
"./ffilldemo [image_name -- Default: fruits.jpg] " << endl; cout << "Hot keys: "
" ESC - quit the program "
" c - switch color/grayscale mode "
" m - switch mask mode "
" r - restore the original image "
" s - use null-range floodfill "
" f - use gradient floodfill with fixed（absolute） range "
" g - use gradient floodfill with floating（relative） range "
" 4 - use 4-connectivity mode "
" 8 - use 8-connectivity mode " << endl;
}Mat image0, image, gray, mask;
int ffillMode = 1;
int loDiff = 20, upDiff = 20;
int connectivity = 4;
int isColor = true;
bool useMask = false;
int newMaskVal = 255;static void onMouse（ int event, int x, int y, int, void* ）
{
if（ event ！= CV_EVENT_LBUTTONDOWN ）
return; Point seed = Point（x,y）;
int lo = ffillMode == 0 ？ 0 : loDiff;
int up = ffillMode == 0 ？ 0 : upDiff;
int flags = connectivity + （newMaskVal << 8） +
（ffillMode == 1 ？ CV_FLOODFILL_FIXED_RANGE : 0）;
int b = （unsigned）theRNG（） & 255;
int g = （unsigned）theRNG（） & 255;
int r = （unsigned）theRNG（） & 255;
Rect ccomp; Scalar newVal = isColor ？ Scalar（b, g, r） : Scalar（r*0.299 + g*0.587 + b*0.114）;
Mat dst = isColor ？ image : gray;
int area; if（ useMask ）
{
threshold（mask, mask, 1, 128, CV_THRESH_BINARY）;
area = floodFill（dst, mask, seed, newVal, &ccomp, Scalar（lo, lo, lo）,
Scalar（up, up, up）, flags）;
imshow（ "mask", mask ）;
}
else
{
area = floodFill（dst, seed, newVal, &ccomp, Scalar（lo, lo, lo）,
Scalar（up, up, up）, flags）;
} imshow（"image", dst）;
cout << area << " pixels were repainted ";
}
int main（）
{
char* filename="0.png";
image0 = imread（filename, 1）; if（ image0.empty（））
{
cout << "Image empty. Usage: ffilldemo <image_name> ";
return 0;
}
help（）;
image0.copyTo（image）;
cvtColor（image0, gray, CV_BGR2GRAY）;
mask.create（image0.rows+2, image0.cols+2, CV_8UC1）; namedWindow（ "image", 0 ）;
createTrackbar（ "lo_diff", "image", &loDiff, 255, 0 ）;
createTrackbar（ "up_diff", "image", &upDiff, 255, 0 ）; setMouseCallback（ "image", onMouse, 0 ）; for（;;）
{
imshow（"image", isColor ？ image : gray）; int c = waitKey（0）;
if（（c & 255） == 27 ）
{
cout << "Exiting ... ";
break;
}
switch（（char）c ）
{
case "c":
if（ isColor ）
{
cout << "Grayscale mode is set ";
cvtColor（image0, gray, CV_BGR2GRAY）;
mask = Scalar::all（0）;
isColor = false;
}
else
{
cout << "Color mode is set ";
image0.copyTo（image）;
mask = Scalar::all（0）;
isColor = true;
}
break;
case "m":
if（ useMask ）
{
destroyWindow（ "mask" ）;
useMask = false;
}
else
{
namedWindow（ "mask", 0 ）;
mask = Scalar::all（0）;
imshow（"mask", mask）;
useMask = true;
}
break;
case "r":
cout << "Original image is restored ";
image0.copyTo（image）;
cvtColor（image, gray, CV_BGR2GRAY）;
mask = Scalar::all（0）;
break;
case "s":
cout << "Simple floodfill mode is set ";
ffillMode = 0;
break;
case "f":
cout << "Fixed Range floodfill mode is set ";
ffillMode = 1;
break;
case "g":
cout << "Gradient （floating range） floodfill mode is set ";
ffillMode = 2;
break;
case "4":
cout << "4-connectivity mode is set ";
connectivity = 4;
break;
case "8":
cout << "8-connectivity mode is set ";
connectivity = 8;
break;
}
} return 0;
}点击图标改变图像中的连图区域的颜色： --------------------------------------分割线 --------------------------------------Ubuntu Linux下安装OpenCV2.4.1所需包 http://www.linuxidc.com/Linux/2012-08/68184.htmUbuntu 12.04 安装 OpenCV2.4.2 http://www.linuxidc.com/Linux/2012-09/70158.htmCentOS下OpenCV无法读取视频文件 http://www.linuxidc.com/Linux/2011-07/39295.htmUbuntu 12.04下安装OpenCV 2.4.5总结 http://www.linuxidc.com/Linux/2013-06/86704.htmUbuntu 10.04中安装OpenCv2.1九步曲 http://www.linuxidc.com/Linux/2010-09/28678.htm基于QT和OpenCV的人脸识别系统 http://www.linuxidc.com/Linux/2011-11/47806.htm[翻译]Ubuntu 14.04, 13.10 下安装 OpenCV 2.4.9 http://www.linuxidc.com/Linux/2014-12/110045.htm--------------------------------------分割线 --------------------------------------OpenCV的详细介绍：请点这里
OpenCV的下载地址：请点这里本文永久更新链接地址：http://www.linuxidc.com/Linux/2015-02/114165.htm