OpenCV 为程序界面添加滑动条

 1 #include <cv.h>
 2 #include <highgui.h>
 3 
 4 using namespace cv;
 5 
 6 /// 全局变量的声明与初始化
 7 const int alpha_slider_max = 100;
 8 int alpha_slider;
 9 double alpha;
10 double beta;
11 
12 /// 声明存储图像的变量
13 Mat src1;
14 Mat src2;
15 Mat dst;
16 
17 /**
18  * @function on_trackbar
19  * @定义响应滑动条的回调函数
20  */
21 void on_trackbar( int, void* )
22 {
23  alpha = (double) alpha_slider/alpha_slider_max ;
24  beta = ( 1.0 - alpha );
25 
26  addWeighted( src1, alpha, src2, beta, 0.0, dst);
27 
28  imshow( "Linear Blend", dst );
29 }
30 
31 int main( int argc, char** argv )
32 {
33  /// 加载图像 (两图像的大小与类型要相同)
34  src1 = imread("../../images/LinuxLogo.jpg");
35  src2 = imread("../../images/WindowsLogo.jpg");
36 
37  if( !src1.data ) { printf("Error loading src1 \n"); return -1; }
38  if( !src2.data ) { printf("Error loading src2 \n"); return -1; }
39 
40  /// 初始化为零
41  alpha_slider = 0;
42 
43  /// 创建窗体
44  namedWindow("Linear Blend", 1);
45 
46  /// 在创建的窗体中创建一个滑动条控件
47  char TrackbarName[50];
48  sprintf( TrackbarName, "Alpha x %d", alpha_slider_max );
49 
50  createTrackbar( TrackbarName, "Linear Blend", &alpha_slider, alpha_slider_max, on_trackbar );
51 
52  /// 结果在回调函数中显示
53  on_trackbar( alpha_slider, 0 );
54 
55  /// 按任意键退出
56  waitKey(0);
57  return 0;
58 }