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OpenCV C++滑动条插件

#include
   
    #include
    
     #include
     
      using namespace cv;using namespace std;int g_slider_position = 0;//储存滑动条的位置，用g_表全局变量，增加代码可读性int g_run = 1;//在新的跳转之后置0，若为正，则表示，在下一次停止前要播放多少帧。int g_dontset = 0;//用来避免在自动运行进度条位置时触发单步模式。VideoCapture g_cap;void onTrackbarSlide(int pos,void *)//回调函数，作为之后创建滑动条的参数实时返回滑动条实时位置，在下面的createTrackbar函数中会使用。{
   	g_cap.set(CAP_PROP_POS_FRAMES, pos);	if (!g_dontset)g_run = 1;//如果g_dontset!=0(用户调整滑动条时)则进入单步模式	g_dontset = 0;//使creatTrackbar里调用回调函数时不进入单步模式}//只有在用户鼠标移动滑动条时才进如单步模式，而自动移动滑动条时，不进入单步模式int main(){
   	namedWindow("Example", WINDOW_AUTOSIZE);	g_cap.open("C:\\Users\\hl\\Desktop\\led.mp4");	int frames = (int)g_cap.get(CAP_PROP_FRAME_COUNT);//得到视频的总帧数	int tmpw = (int)g_cap.get(CAP_PROP_FRAME_WIDTH);//得到视频的宽	int tmph = (int)g_cap.get(CAP_PROP_FRAME_HEIGHT);//得到视频的高	cout << "Video has" << frames << "frames of dimension(" << tmpw << "," << tmph << ")." << endl;	//创建一个滑动条（滑动条名称/窗口名称/引用滑动条当前位置/总帧数(最大值)/回调函数不要可以NULL）	createTrackbar("Position", "Example", &g_slider_position, frames,onTrackbarSlide);	//这个滑动条的名称千万别打错了，就因为我打成一次position，并不报错，但是运行的时候滑动条始终不动！！！因为动的是另一个看不见的滑动条....	//像这种P和p的错误，找起来太费劲了，我服了。	Mat frame;	while (1)	{
   			if (g_run != 0)		{
   			g_cap >> frame;//VideoCapture重载了>>运算符，得到帧。						if (frame.empty())break;			int current_pos = (int)g_cap.get(CAP_PROP_POS_FRAMES);			g_dontset = 1;			//g_donset不为0时,回调函数内部会设置g_run=1进入单步模式			setTrackbarPos("Position", "Example", current_pos);			imshow("Example", frame);			if(g_run>0) g_run -= 1;			//只有在g_run大于0时才-1，不然在播放视频的时候，每帧都要多做一次减法，减少一些运算量嘛，能节约一点是一点。		}		char c = (char)waitKey(10);		if (c =='s')//逐帧模式		{
   			g_run = 1;			cout << "Single step ,run=" << g_run << endl;		}		if (c == 'r')//运行模式		{
   			g_run = - 1;			cout << "Run mode ,run=" << g_run << endl;		}		if (c == 27)break;//点击ESC退出程序	}	waitKey(0);	destroyWindow("Example");//销毁窗口习惯，减少内存泄漏的机会	return 0;}
     
    
   

效果成功后

此外，对于一般的调参数改变图像的例子。

#include
   
    using namespace cv;Mat img;//输入图片Mat out;//输出图片int g_slide_position = 0;//滑动条当前位置const int g_max_position = 8;//滑动条最大位置void onTrackbarSlide(int, void*){
   	out = img.clone();//将原图复制一份到输出图里//******************************************************************//*内的内容可替换成需要的参数以及函数，这边为降采样的次数	for (int i = 0; i < g_slide_position; i++)	{
   		pyrDown(out, out);//降采样一次	}//******************************************************************	imshow("输出图像", out);}int main(){
   	img = imread("C:\\Users\\hl\\Desktop\\lena1.jpg");	namedWindow("输出图像", WINDOW_NORMAL);	createTrackbar("降采样次数", "输出图像", &g_slide_position, g_max_position, onTrackbarSlide);	onTrackbarSlide(0,0);	waitKey();	return 0;}
   

#include
   
    #include
    
     using namespace cv;using namespace std;Mat screen = Mat(10, 10, CV_8UC1, Scalar(0));int g_slide_position = 0;Mat code(int num)//数字编码{
   	Mat_
     
       num_code;	switch (num)	{
   	case 0:		num_code = Mat(10, 10, CV_8UC1,Scalar(0));		for(int i=2;i<8;i++)		{
   			num_code(1, i) = 255;			num_code(7, i) = 255;			num_code(i, 2) = 255;			num_code(i, 7) = 255;		}		return num_code;	case 1:		num_code = Mat(10, 10, CV_8UC1, Scalar(0));		for (int i = 1; i < 9; i++)		{
   			num_code(i,7) = 255;		}		return num_code;	case 2:		num_code = Mat(10, 10, CV_8UC1, Scalar(0));		for (int i = 2; i < 8; i++)		{
   			num_code(1, i) = 255;			num_code(4, i) = 255;			num_code(7, i) = 255;		}		num_code(2, 7) = 255;		num_code(3, 7) = 255;		num_code(5, 2) = 255;		num_code(6, 2) = 255;		return num_code;	case 3:		num_code = Mat(10, 10, CV_8UC1, Scalar(0));		for (int i = 2; i < 8; i++)		{
   			num_code(1, i) = 255;			num_code(4, i) = 255;			num_code(7, i) = 255;		}		num_code(2, 7) = 255;		num_code(3, 7) = 255;		num_code(5, 7) = 255;		num_code(6, 7) = 255;		return num_code;	case 4:		num_code = Mat(10, 10, CV_8UC1, Scalar(0));		for (int i = 1; i < 8; i++)		{
   			num_code(i, 7) = 255;		}		for (int i = 1; i < 5; i++)		{
   			num_code(i, 2) = 255;		}		num_code(4, 3) = 255;		num_code(4, 4) = 255;		num_code(4, 5) = 255;		num_code(4, 6) = 255;		return num_code;	case 5:		num_code = Mat(10, 10, CV_8UC1, Scalar(0));		for (int i = 2; i < 8; i++)		{
   			num_code(1, i) = 255;			num_code(4, i) = 255;			num_code(7, i) = 255;		}		num_code(2, 2) = 255;		num_code(3, 2) = 255;		num_code(5, 7) = 255;		num_code(6, 7) = 255;		return num_code;	case 6:		num_code = Mat(10, 10, CV_8UC1, Scalar(0));		for (int i = 2; i < 8; i++)		{
   			num_code(1, i) = 255;			num_code(4, i) = 255;			num_code(7, i) = 255;		}		num_code(2, 2) = 255;		num_code(3, 2) = 255;		num_code(5, 2) = 255;		num_code(6, 2) = 255;		num_code(5, 7) = 255;		num_code(6, 7) = 255;		return num_code;	case 7:		num_code = Mat(10, 10, CV_8UC1, Scalar(0));		for (int i = 3; i < 8; i++)		{
   			num_code(1, i) = 255;		}		for (int i = 2; i < 9; i++)		{
   			num_code(i, 7) = 255;		}		return num_code;	case 8:		num_code = Mat(10, 10, CV_8UC1, Scalar(0));		for (int i = 2; i < 8; i++)		{
   			num_code(1, i) = 255;			num_code(4, i) = 255;			num_code(7, i) = 255;		}		num_code(2, 2) = 255;		num_code(3, 2) = 255;		num_code(5, 2) = 255;		num_code(6, 2) = 255;		num_code(5, 7) = 255;		num_code(6, 7) = 255;		num_code(2, 7) = 255;		num_code(3, 7) = 255;		return num_code;	case 9:		num_code = Mat(10, 10, CV_8UC1, Scalar(0));		for (int i = 2; i < 8; i++)		{
   			num_code(1, i) = 255;			num_code(4, i) = 255;			num_code(7, i) = 255;		}		num_code(2, 2) = 255;		num_code(3, 2) = 255;		num_code(2, 7) = 255;		num_code(3, 7) = 255;		num_code(5, 7) = 255;		num_code(6, 7) = 255;	}	return num_code;}void screen_initial()//展示初始化{
   	for (int i = 1; i < 9; i++)	{
   		screen.at
      
       (i, 1) = 255;		screen.at
       
        (i, 4) = 255;		screen.at
        
         (i, 6) = 255; } for (int i = 7; i < 9; i++) { screen.at
         
          (8, i) = 255; } screen.at
          
           (4, 2) = 255; screen.at
           
            (4, 3) = 255;}void onTrackbarSlide(int, void*)//滑动条回调函数{ screen = code(g_slide_position); imshow("out", screen);}int main(){ screen_initial();//初始化展示 我的名字啊HL namedWindow("out", WINDOW_NORMAL); imshow("out", screen); createTrackbar("num", "out", &g_slide_position, 9, onTrackbarSlide); waitKey(0); return 0;}
           
          
         
        
       
      
     
    
   

运行程序显示初始化界面：我的名字哈哈。

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