CV_Alpha_Blending

// OpenCV Alpha Blending Tutorial modified for Face Morphing
#include <cv.h>
#include <highgui.h>
#include <iostream>

using namespace cv;
using namespace std;

int main()
{
  double alpha = 0.5, beta, input; 

	Mat src1, src2, dst;
	
	// Ask user to enter alpha
	cout << " Simple Linear Blender " << endl;
	cout << "-----------------------" << endl;
	cout << " Enter alpha [0-1]: ";
	cin >> input;

	// We use the alpha provided by user if its between 0 and 1
	if( input >= 0.0 && input <= 1.0 )
		alpha = input;

	// Read image (same size, same type )
	src1 = imread("f1.jpg");//Linux.jpg");//atom.jpg");//"Linux.jpg"); //f1.jpg
	src2 = imread("f2.jpg");//Windows.jpg");//fool.jpg");//"Windows.jpg"); //f2.jpg

	if( !src1.data ) { printf("Error loadind src1 \n"); return -1;}
	if( !src2.data ) { printf("Error loadind src2 \n"); return -1;}

	// Create windows
	//namedWindow("Windows Logo", CV_WINDOW_AUTOSIZE );
	//namedWindow("Linux Logo", CV_WINDOW_AUTOSIZE );
	namedWindow("Linear Blend", CV_WINDOW_AUTOSIZE );

	//imshow( "Linux Logo", src1 );
	//imshow( "Windows Logo", src2 );

	// Uncomment the below 'for' loop for morphing effect
	for(int k = 0; k <= 100; ++k )
	{
		alpha = (double)k/100;
		beta  = 1 - alpha;

	//double t = (double)getTickCount(); // To calculate time reqd.
		addWeighted( src2, alpha, src1, beta, 0.0, dst );
	//t = ((double)getTickCount() - t)/getTickFrequency();

	//cout << "Linear blnding took " << t*1000 << " milliseconds." << endl;
		
		//imwrite("CV_Blending_dst_Gamma0.jpg", dst);
		imshow( "Linear Blend", dst );
		cvWaitKey(50);
	}
	cvWaitKey();
	return 0;

}