滑動條需要一個回調函數 ,好處就是可以更改一些參數的值 直接看到狀態變化,以圖像疊加爲例
Mat Img1;
Mat Img2;
Mat OutImg;
int alpha=0;
void WeightTrackbar(int, void*); //響應滑動條的回調函數
int main()
{
Img1 = imread("demo.jpg");
if (!Img1.data)
{
cout << "未找到圖片" << endl;
return -1;
}
Img2 = Mat(Img1.size(), Img1.type());
Img2 = Scalar(0, 0, 0);//BGR
namedWindow("Output Img");
createTrackbar("Weight of Img1", "Output Img", &alpha, 100, WeightTrackbar);
//滑動條的name 放在的窗口name 變動的值* 最大值 回調函數
WeightTrackbar(alpha, 0);
waitKey(0);
return 0;
}
void WeightTrackbar(int, void*)
{
//根據更改的alpha的值重新疊加圖片
addWeighted(Img1, alpha * 0.01, Img2, 1 - alpha * 0.01, 0, OutImg);
imshow("Output Img", OutImg);
}