#include <cv.h>
#include <highgui.h>
#include <math.h>
#include <stdio.h>



//CREATION OF SIMPLE IMAGE
int prog1(){
IplImage *cvImg; // image used for visualisation
CvSize imgSize; // size of visualisation image
int i = 0, j = 0;
imgSize.width = 640; // visualisation image is
imgSize.height = 480; // 640x480 pixels
// creation of a 8 bits depth gray image
cvImg = cvCreateImage( imgSize, 8, 1 ); //8 bits (i.e. 256 gray levels), 1 channel (i.e. monochrome)
// image is filled with gray values
// corresponding to the 256 modulus
// of their position in the image
for ( i = 0; i < imgSize.width; i++ )
  for ( j = 0; j < imgSize.height; j++ )
((uchar*)(cvImg->imageData + cvImg->widthStep*j))[i] = ( char ) ( ( i + j ) % 256 );

cvNamedWindow( "Testing OpenCV...", 1 ); // creation of a visualisation window
cvShowImage( "Testing OpenCV...", cvImg ); // image visualisation

cvWaitKey( 0 ); // wait for key
cvDestroyWindow( "image" ); // close window
cvReleaseImage( &cvImg ); // memory release before exiting the application
return( 0 );
}


//SIMPLE FILTER
int prog2(int argcc, char **argvv){
 CvPoint center;
     double scale=-3;
     IplImage* image =
         cvLoadImage(argcc == 2 ? argvv[1] : "lena.jpg");

     if(!image) return -1;

     center = cvPoint(image->width/2,image->height/2);

     for(int i=0;i<image->height;i++)
        for(int j=0;j<image->width;j++)
        {
           double dx=(double)(j-center.x)/center.x;
           double dy=(double)(i-center.y)/center.y;
           double weight=exp((dx*dx+dy*dy)*scale);
           uchar* ptr = &CV_IMAGE_ELEM(image,uchar,i,j*3);
           ptr[0] = cvRound(ptr[0]*weight);
           ptr[1] = cvRound(ptr[1]*weight);
           ptr[2] = cvRound(ptr[2]*weight);
        }
     cvNamedWindow( "test", 1 );
     cvShowImage( "test", image );
	 cvSaveImage("copy.png", image);
     cvWaitKey();
	 return (0);
     
}


//Testing some filters
int prog3(int argcc, char **argvv){
 
     IplImage* image = cvLoadImage(argcc == 2 ? argvv[1] : "lena.jpg");

     if(!image) return -1;

    // IplImage *outputimage=cvCloneImage(image);
	 CvSize imgSize;
     IplImage *bwimage;
	imgSize.width = image->width; // visualisation image is
     imgSize.height = image->height; // 640x480 pixels
     // creation of a 8 bits depth monochrome image
     bwimage = cvCreateImage( imgSize, 8, 1 );
	 
	 //Convert the color image into a gray-scale one
    cvCvtColor(image, bwimage,CV_BGR2GRAY); // BW

  //Sobel -->>UNCOMMENT FOR RESULT
 //IplImage *outputimage=cvCloneImage(bwimage);
 //cvSobel(bwimage, outputimage, 1, 1, 3);

  //Laplace in sll 3 color channels -->> UNCOMMENT FOR RESULT
  /*IplImage *outputimage=cvCreateImage( imgSize, IPL_DEPTH_32F, 3);
  cvLaplace(image, outputimage, 3);*/

  //Laplace in grayscale image -->> UNCOMMENT FOR RESULT
  //IplImage *outputimage=cvCreateImage( imgSize, IPL_DEPTH_32F, 1);
  //cvLaplace(bwimage, outputimage, 5);

  //Corner detector -->>UNCOMMENT FOR RESULT 
  //IplImage *outputimage=cvCreateImage(imgSize, IPL_DEPTH_32F, 1);
  //cvPreCornerDetect( bwimage, outputimage, 7 );

  //Convolution with kernel
   int nrows=5;
    int ncols=5;
	//CvMat* kernelmatrix=cvCreateMat( nrows, ncols, CV_8UC1  );

	float a[25]; 
	for (int i=0; i<25; ++i) a[i]=1.0/25.0;

    CvMat kernelmatrix;

    cvInitMatHeader( &kernelmatrix, nrows, ncols, CV_32FC1, a );
	
	IplImage *outputimage=cvCreateImage(imgSize, IPL_DEPTH_8U, 1);
	cvFilter2D( bwimage, outputimage, &kernelmatrix);
	
 printf( "input image depth: %d\n", image->depth);
 printf( "bw image depth: %d\n", bwimage->depth);
 printf( "outputimage depth: %d\n", outputimage->depth);
	 
 cvNamedWindow( "input", 1 );
 cvShowImage( "input", image );

 cvNamedWindow( "bw", 1 );
 cvShowImage( "bw", bwimage );

 cvNamedWindow( "output", 1 );
 cvShowImage( "output", outputimage );


	 //cvSaveImage("copy.png", outputimage);
     cvWaitKey();
	 return (0);
     
}


//Canny Edge Detector from Stanford's course
void prog_stanford1(){
	CvvImage im;			// create image variable
  im.Load("lena.jpg");	// load image from file system
  cvNamedWindow("main", 0);	// create display window
  im.Show("main");		// show image in window

  CvvImage imBW;		// create image variable
  imBW.Create(im.Width(), im.Height(), 8);	// allocate
  cvCvtColor(im.GetImage(), imBW.GetImage(),CV_BGR2GRAY); // BW

  cvNamedWindow("bw", 0);	// create display window
  imBW.Show("bw");		// show image in window

  CvvImage imCanny;		// create image variable
  imCanny.Create(imBW.Width(), imBW.Height(), 8); // allocate
  cvCanny(imBW.GetImage(), imCanny.GetImage(), 25, 75, 3); // Canny edges

  cvNamedWindow("canny", 0);	// create display window
  imCanny.Show("canny");	// show image in window
  imCanny.Save("canny.jpg");		// save the result

  for (;;) 
    cvWaitKey(0);	
}
int main( int argc, char** argv )
{

//return prog1();
//return prog2(argc, argv);
//return prog3(argc, argv);
	prog_stanford1();


    
}