OpenCV响应鼠标函数cvSetMouseCallback()和其副程式onMouse()的使用(OpenCV2.4.5).doc

每當滑鼠在視訊視窗介面點擊一下的時候,都會有固定三個動作1.點擊(Click)2.放開(Down)3.滑動(move)因此,程式執行滑鼠在點擊的時候onMouse()都會連續跑三次,代表滑鼠在點擊的時候連續的三個事件,而void onMouse(int Event,int x,int y,int flags,void* param ) 副程式的引數分成四個不同的分類,分別為1.事件回傳代號(int Event)2.座標(int x,int y)3.flags代號(int flags)4.Mouse事件的代號名稱(param)Event代表的是滑鼠回傳的事件號碼,每當滑鼠有動作,Event就會回傳一個整數訊息到onMouse(),也順便回傳滑鼠移動的座標,flags代表的是拖曳事件,param則是自己定義onMouse()事件的ID,就跟GUI介面的視窗介面ID一樣(cvGetWindowHandle(),不過這邊是自己給的編號,而視窗介面的ID則是系統自動隨機分配的ID,而滑鼠事件的執行可以細分的分類為Event:#define CV_EVENT_MOUSEMOVE 0 滑動#define CV_EVENT_LBUTTONDOWN 1 左鍵點擊#define CV_EVENT_RBUTTONDOWN 2 右鍵點擊#define CV_EVENT_MBUTTONDOWN 3 中鍵點擊#define CV_EVENT_LBUTTONUP 4 左鍵放開#define CV_EVENT_RBUTTONUP 5 右鍵放開#define CV_EVENT_MBUTTONUP 6 中鍵放開#define CV_EVENT_LBUTTONDBLCLK 7 左鍵雙擊#define CV_EVENT_RBUTTONDBLCLK 8 右鍵雙擊#define CV_EVENT_MBUTTONDBLCLK 9 中鍵雙擊flags:#define CV_EVENT_FLAG_LBUTTON 1 左鍵拖曳#define CV_EVENT_FLAG_RBUTTON 2 右鍵拖曳#define CV_EVENT_FLAG_MBUTTON 4 中鍵拖曳#define CV_EVENT_FLAG_CTRLKEY 8 (815)按Ctrl不放事件#define CV_EVENT_FLAG_SHIFTKEY 16 (1631)按Shift不放事件#define CV_EVENT_FLAG_ALTKEY 32 (3239)按Alt不放事件上面的#define是OpenCV自行定義的參數,要做事件捕捉的時候,可以用參數,亦可以用純數字表示.簡單的介紹mouse相關的東西.cvSetMouseCallback()滑鼠事件呼叫函式,需要給它一個Handler,也就是事件驅動的副程式名稱,Handler必須要符合void xxx(int event,int x,int y,int flags,void* param )格式.cvSetMouseCallback(視窗名稱,自行定義副程式名稱,自行定義副程式名稱的ID);onMouse()自行定義的滑鼠事件名稱,可以接受滑鼠訊息做相關控制.void xxx(事件訊息整數代號,滑鼠x軸座標,滑鼠y軸座標,拖曳事件訊息整數代號,自行給予xxx這副程式的ID編號)实例：利用鼠标绘制直线并显示像素坐标和像素值cpp view plaincopyprint?1 #include 2 using namespace cv; 3 4 Mat src,dst; 5 6 void on_mouse( int event, int x, int y, int flags, void* ustc) 7 8 /src = imread(Lena.jpg); 9 10 static Point pre_pt = (-1,-1); 11 static Point cur_pt = (-1,-1); 12 CvFont font; 13 cvInitFont(&font, CV_FONT_HERSHEY_SIMPLEX, 0.5, 0.5, 0, 1, CV_AA); 14 char temp50; 15 16 Vec3b intensity = src.at(Point(x, y); 17 if( event = CV_EVENT_LBUTTONDOWN ) 18 19 dst.copyTo(src); 20 sprintf(temp,(%d,%d,%d,%d,%d),x,y,intensity.val0,intensity.val1,intensity.val2); 21 pre_pt = cvPoint(x,y); 22 putText(src,temp, pre_pt, FONT_HERSHEY_SIMPLEX, 0.5,cvScalar(0,0, 0, 255),1,8); 23 circle( src, pre_pt, 3,cvScalar(255,0,0,0) ,CV_FILLED, CV_AA, 0 ); 24 imshow( src, src ); 25 src.copyTo(dst); 26 27 else if( event = CV_EVENT_MOUSEMOVE & (flags & CV_EVENT_FLAG_LBUTTON) 28 29 dst.copyTo(src); 30 sprintf(temp,(%d,%d,%d,%d,%d),x,y,intensity.val0,intensity.val1,intensity.val2); 31 cur_pt = cvPoint(x,y); 32 putText(src,temp, cur_pt,FONT_HERSHEY_SIMPLEX, 0.5,cvScalar(0,0, 0, 255),1,8); 33 line(src, pre_pt, cur_pt, cvScalar(0,255,0,0), 1, CV_AA, 0 ); 34 imshow( src, src ); 35 36 else if( event = CV_EVENT_LBUTTONUP ) 37 38 dst.copyTo(src); 39 sprintf(temp,(%d,%d,%d,%d,%d),x,y,intensity.val0,intensity.val1,intensity.val2); 40 cur_pt = Point(x,y); 41 putText(src,temp, cur_pt, FONT_HERSHEY_SIMPLEX, 0.5,cvScalar(0,0, 0, 255),1,8); 42 circle( src, cur_pt, 3,cvScalar(255,0,0,0) ,CV_FILLED, CV_AA, 0 ); 43 line( src, pre_pt, cur_pt, cvScalar(0,255,0,0), 1, CV_AA, 0 ); 44 imshow( src, src ); 45 src.copyTo(dst); 46 47 48 49 int main() 50 51 src = imread(Lena.jpg); 52 53 src.copyTo(dst); 54 cvNa