1.opencv API及参数介绍
cv::setMouseCallback(const string& windowname, MouseCallback onMouse, void* userdata=0)
{
....
}
// windowname: 要操作的窗口名称
// onMouse: 鼠标事件函数，鼠标事件发生以后，要执行的回调函数。函数原型是
// void onMouse(int event, int x, int y, int flags, void * para)
// userdata: 回调函数的参数
鼠标回调函数介绍：
void onMouse(int event, int x, int y, int flags, void *para)
// int event: 鼠标事件，见后续说明
// x, y 是鼠标在图像坐标系中的坐标
// flags :
// para： 是用户传递到回调函数中的参数
截取感兴趣区域ROI：
cv::selectROIs("MultiTracker", frame, bboxes_, showCrosshair, fromCenter);
// “MultiTracker” : windowsName
// frame: 当前画面；格式为cv::Mat
// bboxes： 要存储的框框格式为：std::vector<cv::Rect>
// showCrosshair:默认为True
// fromCenter:从中心点还是从对角点，默认为false，为true时，选框从中心点开始
涉及的相关参数：
// EVENT的参数定义
enum
{
CV_EVENT_MOUSEMOVE =0,//滑动
CV_EVENT_LBUTTONDOWN =1,//左键点击
CV_EVENT_RBUTTONDOWN =2,//右键点击
CV_EVENT_MBUTTONDOWN =3,//中键点击
CV_EVENT_LBUTTONUP =4,//左键放开
CV_EVENT_RBUTTONUP =5,//右键放开
CV_EVENT_MBUTTONUP =6,//中键放开
CV_EVENT_LBUTTONDBLCLK =7,//左键双击
CV_EVENT_RBUTTONDBLCLK =8,//右键双击
CV_EVENT_MBUTTONDBLCLK =9//中键双击
};
enum
{
CV_EVENT_FLAG_LBUTTON =1,//左键拖拽
CV_EVENT_FLAG_RBUTTON =2,//右键拖拽
CV_EVENT_FLAG_MBUTTON =4,//中键拖拽
CV_EVENT_FLAG_CTRLKEY =8,//按CTRL不放
CV_EVENT_FLAG_SHIFTKEY =16,//按SHIFT不放
CV_EVENT_FLAG_ALTKEY =32//按ALT不放
};
或者python-opencv中的参数也相同：
# mouse callback function
def mouse_event(event, x, y, flags, param):
'''
:param event: 点击事件标识
:param x: 坐标x
:param y: 坐标y
:param flags:按键事件标识
:param param: 携带参数
:return:
'''
if flags == cv2.EVENT_FLAG_ALTKEY:
print('摁住Alt')
if flags == cv2.EVENT_FLAG_CTRLKEY:
print('摁住Ctrl')
if flags == cv2.EVENT_FLAG_SHIFTKEY:
print('摁住Shift')
if flags == cv2.EVENT_FLAG_LBUTTON:
print('摁住左键')
if flags == cv2.EVENT_FLAG_MBUTTON:
print('摁住中键')
if flags == cv2.EVENT_FLAG_RBUTTON:
print('摁住右键')
if event == cv2.EVENT_LBUTTONDBLCLK:
print('左键双击')
if event == cv2.EVENT_MBUTTONDBLCLK:
print('中键双击')
if event == cv2.EVENT_RBUTTONDBLCLK:
print('右键双击')
if event == cv2.EVENT_LBUTTONDOWN:
print('左键击下')
if event == cv2.EVENT_LBUTTONUP:
print('左键弹起')
if event == cv2.EVENT_MBUTTONDOWN:
print('中键击下')
if event == cv2.EVENT_MBUTTONUP:
print('中键弹起')
if event == cv2.EVENT_RBUTTONDOWN:
print('右键击下')
if event == cv2.EVENT_RBUTTONUP:
print('右键弹起')
if event == cv2.EVENT_MOUSEWHEEL:
if flags > 0:
print('向前滚动')
else:
print('向后滚动')
if event == cv2.EVENT_MOUSEHWHEEL:
if flags > 0:
print('向左滚动') # 按住Alt
else:
print('向右滚动')
if __name__ == '__main__':
img = np.mat(np.zeros((300, 300, 3), np.uint8)) # 构造一个像素值全为1的图形
cv2.namedWindow('mouse') #命名窗口为mouse
cv2.setMouseCallback('mouse', mouse_event) # 窗口与回调函数绑定
while True:
cv2.imshow('mouse', img)
if cv2.waitKey(1) & 0xFF == ord('q'): # 摁下q退出
break
cv2.destroyAllWindows() #销毁所有窗口
2.一个可以绘制矩形和控制缩放的demo
#include <opencv2/opencv.hpp>
using namespace std;
using namespace cv;
#define WINNAME "画板"
struct MouseParam
{
Mat img; //用于画好一个后显示
Mat imgZoomBackup; //用于zoom的还原备份
Mat imgTmp; //用于实时显示
Mat imgBackup; //清空，显示最初的图
Point pt1;
Point pt2;
bool mouseLflag;
float scale;
};
//绘制矩形
void draw_rectangle(Mat& img, const Point& pt1, const Point& pt2)
{
rectangle(img, pt1, pt2, Scalar(0, 255, 0), 1, 0, 0);
}
//绘制十字线：即过一点的水平、竖直线
void draw_crossline(Mat& img, const Point& pt)
{
int width = img.cols;
int height = img.rows;
cv::Point ptv1;
cv::Point ptv2;
cv::Point pth1;
cv::Point pth2;
ptv1 = cv::Point(pt.x, 0);
ptv2 = cv::Point(pt.x, height);
pth1 = cv::Point(0, pt.y);
pth2 = cv::Point(width, pt.y);
cv::line(img, ptv1, ptv2, Scalar(255, 255, 0), 1);
cv::line(img, pth1, pth2, Scalar(255, 255, 0), 1);
}
void zoom(Mat& img, const Mat& srcimg, const Point& pt, const float scale)
{
int x1, y1, x2, y2;
int width, height;
width = (int)(srcimg.cols * scale / 2.0);
height = (int)(srcimg.rows * scale / 2.0);
x1 = max(pt.x - width, 0);
y1 = max(pt.y - height, 0);
x2 = min(pt.x + width, srcimg.cols);
y2 = min(pt.y + height, srcimg.rows);
Rect zoomRect(Point(x1, y1), Point(x2, y2));
img = srcimg(zoomRect).clone();
}
void on_mouse(int event, int x, int y, int flags, void* param)
{
MouseParam* par = (MouseParam*)param;
Point pt(x, y);
double value;
float step = 0.05;
if (event == EVENT_RBUTTONDOWN) //按下右键，重画
{
par->img = par->imgBackup.clone();
}
else if (event == EVENT_LBUTTONDOWN) //按下左键
{
par->pt1 = pt;
par->pt2 = pt;
par->mouseLflag = true;
}
else if (event == EVENT_MOUSEMOVE && flags == EVENT_FLAG_LBUTTON) //按下左键并移动
{
par->pt2 = pt;
}
else if (event == EVENT_LBUTTONUP)//左键放开进行绘制矩形框
{
par->pt2 = pt;
draw_rectangle(par->img, par->pt1, par->pt2);
//par->imgZoomBackup = par->img.clone();
par->mouseLflag = false;
}
else if (event == EVENT_MOUSEMOVE) //鼠标移动将显示十字线
{
par->pt1 = pt;
}
else if (event == EVENT_MOUSEWHEEL) //鼠标滚动
{
value = getMouseWheelDelta(flags);
if (value > 0) //滚轮向前滚动，设为缩小
par->scale += step;
else if (value < 0) //鼠标向后滚动，设为放大
par->scale -= step;
par->scale = max((float)0.3, par->scale);
par->scale = min((float)1.0, par->scale);
zoom(par->img, par->imgZoomBackup, par->pt1, par->scale);
}
}
int main()
{
//Mat img(512, 512, CV_8UC3, Scalar::all(255));
Mat img = imread("./imgs/1/L.png");
MouseParam mouseParam;
mouseParam.img = img.clone();
mouseParam.imgBackup = img.clone();
mouseParam.imgZoomBackup = img.clone();
mouseParam.mouseLflag = false;
float step = 0.05;
mouseParam.scale = 1.0;
namedWindow(WINNAME, 0);
setMouseCallback(WINNAME, on_mouse, &mouseParam);
int key;
while (1)
{
mouseParam.imgTmp = mouseParam.img.clone();
draw_crossline(mouseParam.imgTmp, mouseParam.pt1);
if (mouseParam.mouseLflag == true)
draw_rectangle(mouseParam.imgTmp, mouseParam.pt1, mouseParam.pt2);
imshow(WINNAME, mouseParam.imgTmp);
key = waitKey(40);
if (key == 27)
{
break;
}
else if (key == toascii('q'))
{
mouseParam.scale -= step;
zoom(mouseParam.img, mouseParam.imgZoomBackup, mouseParam.pt1, mouseParam.scale);
}
else if (key == toascii('e'))
{
mouseParam.scale += step;
zoom(mouseParam.img, mouseParam.imgZoomBackup, mouseParam.pt1, mouseParam.scale);
}
}
return 0;
}3.图象中画点
- 对于拼接后的图像显示窗口，依次绘制左右图中的对应点程序
- 右键删除尚未调通
std::vector<cv::Point2f>pointsL; //依次存放左右图中的对应点
std::vector<cv::Point2f>pointsR;
cv::Mat mask;
cv::Point2f p_;
//鼠标回调函数
void on_mouse(int event, int x, int y, int flags, void* param)
{
float cols = mask.cols/2;
int rad = 6;
if (event == cv::EVENT_LBUTTONUP || !(flags & cv::EVENT_FLAG_LBUTTON))
cv::Point2f pt = cv::Point2f(-10, -10);
else if (event == cv::EVENT_LBUTTONDOWN)
{
cv::Point2f pt(x, y);
if (pt.x>=0&&pt.x <= cols)
{
pointsL.push_back(pt);
cv::circle(mask, pt, rad, cv::Scalar(0, 255, 0), 2);
}
else {
pointsR.push_back(pt);
cv::circle(mask, pt, rad, cv::Scalar(0, 0, 255), 2);
}
//cv::circle(mask, pt, 2, cv::Scalar(0, 255, 0), 2);
cv::imshow("image", mask);
}
else if (event == cv::EVENT_RBUTTONDOWN) //按下右键，重画
{
cv::Point2f pt(x, y);
if (pointsL.size()>0)
{
pointsL.pop_back();
}
else if (pointsR.size() > 0)
{
pointsR.pop_back();
}
}
std::cout << "pointsL" << std::endl;
for (int i = 0; i < pointsL.size(); ++i)
{
std::cout << pointsL[i] << std::endl;
}
std::cout << "pointsR" << std::endl;
for (int i = 0; i < pointsR.size(); ++i)
{
std::cout << pointsR[i] << std::endl;
}
}4.opencv例程分水岭分割中的界面应用
鼠标时间包含绘制直线的交互操作
static void help(char** argv)
{
cout << "\nThis program demonstrates the famous watershed segmentation algorithm in OpenCV: watershed()\n"
"Usage:\n" << argv[0] << " [image_name -- default is fruits.jpg]\n" << endl;
cout << "Hot keys: \n"
"\tESC - quit the program\n"
"\tr - restore the original image\n"
"\tw or SPACE - run watershed segmentation algorithm\n"
"\t\t(before running it, *roughly* mark the areas to segment on the image)\n"
"\t (before that, roughly outline several markers on the image)\n";
}
Mat markerMask, img;
Point prevPt(-1, -1);
static void onMouse(int event, int x, int y, int flags, void*)
{
if (x < 0 || x >= img.cols || y < 0 || y >= img.rows)
return;
if (event == EVENT_LBUTTONUP || !(flags & EVENT_FLAG_LBUTTON))
prevPt = Point(-1, -1);
else if (event == EVENT_LBUTTONDOWN)
prevPt = Point(x, y);
else if (event == EVENT_MOUSEMOVE && (flags & EVENT_FLAG_LBUTTON))
{
Point pt(x, y);
if (prevPt.x < 0)
prevPt = pt;
line(markerMask, prevPt, pt, Scalar(12,234,12), 40, 8, 0);
line(img, prevPt, pt, Scalar(12,234,12), 40, 8, 0);
prevPt = pt;
imshow("image", img);
}
}
int main(int argc, char** argv)
{
cv::CommandLineParser parser(argc, argv, "{help h | | }{ @input | fruits.jpg | }");
if (parser.has("help"))
{
help(argv);
return 0;
}
//string filename = samples::findFile(parser.get<string>("@input"));
Mat img0 = imread("..."), imgGray;
if (img0.empty())
{
cout << "Couldn't open image ";
help(argv);
return 0;
}
help(argv);
//img0 = img0(Rect(1000, 1000, 800, 800));
namedWindow("image", WINDOW_NORMAL);
img0.copyTo(img);
cvtColor(img, markerMask, COLOR_BGR2GRAY);
cvtColor(markerMask, imgGray, COLOR_GRAY2BGR);
markerMask = Scalar::all(0);
imshow("image", img);
setMouseCallback("image", onMouse, 0);
for (;;)
{
char c = (char)waitKey(0);
if (c == 27)
break;
if (c == 'r')
{
markerMask = Scalar::all(0);
img0.copyTo(img);
namedWindow("image", WINDOW_NORMAL);
imshow("image", img);
}
if (c == 'w' || c == ' ')
{
//对绘制完成的图像进行下一步操作
//须在键入相应按键后执行
}
}
return 0;
}到此这篇关于Opencv实现鼠标事件与窗口互动功能过程的文章就介绍到这了,更多相关Opencv鼠标事件与窗口互动内容请搜索编程网以前的文章或继续浏览下面的相关文章希望大家以后多多支持编程网！
