opencv-1.cpp

#include <stdio.h>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>

using namespace cv;

int main( int argc, char** argv ) {
  Mat image;
  image = imread( argv[1], 1 );

  if( argc != 2 || !image.data ) {
      printf( "No image data \n" );
      return -1;
  }
  Mat new_image = Mat::zeros( image.size(), image.type() );

  double alpha = 1.5;
  double beta = 75;
  /// Do the operation new_image(i,j) = alpha*image(i,j) + beta
  for( int y = 0; y < image.rows; y++ ) {
    for( int x = 0; x < image.cols; x++ ) {
      for( int c = 0; c < 3; c++ ) {
        new_image.at<Vec3b>(y,x)[c] = saturate_cast<uchar>( alpha*( image.at<Vec3b>(y,x)[c] ) + beta );
      }
    }
  }
  imwrite("alpha.jpg", new_image);
  return 0;
}