Alpha Blending

代码

//===============================================================
//FileName:
//          AlphaBlending.cpp
//Date:
//          2019/11/24
//Author:
//          khoing(https://blog.youkuaiyun.com/qq_45391763)
//===============================================================

#include <opencv2/opencv.hpp>

using namespace cv;
using namespace std;



// Alpha blending using multiply and add functions
Mat& blend(Mat& alpha, Mat& foreground, Mat& background, Mat& outImage)
{
   
	Mat fore, back;
	multiply(alpha, foreground, fore);
	multiply(Scalar::all(1.0) - alpha, background, back);
	add(fore, back, outImage);

	return outImage;
}

//------------------------------------------------------------------------



// 直接使用指针进行Alpha混合
Mat& alphaBlendDirectAccess(Mat& alpha, Mat& foreground, Mat& background, Mat& outImage)
{
   

	int numberOfPixels = foreground.rows * foreground.cols * foreground.channels();


	//指针默认指向各个图像的第一个像素
	float* fptr = reinterpret_cast<float*