Non-recursive blobDetection using queue . Centroid also implemented

BlobDetection

//Author :Kumar Krishna Agarwal
//Mail   :kumar.1994.14@gmail.com

#include <stdio.h> 
#include <highgui.h> 
#include <cv.h> 
#include <cxcore.h> 
  
#include <stdio.h> 
#include <stdlib.h>

#define PIX(img,i,j,k) (((uchar*)img->imageData)[(i)*img->widthStep+(j)*img->nChannels+(k)])
  
typedef struct node 
{ 
    int x; 
    int y; 
    struct node *next; 
}node;

node *rear,*front;

int isEmpty() 
{ 
    if(front==NULL) 
        return 1; 
    else return 0; 
} 
void enqueue(int x,int y) 
{ 
    node* t; 
    t=(node*)malloc(sizeof(node)); 
    t->x=x; 
    t->y=y; 
    t->next=NULL; 
    if(isEmpty()) 
    { 
        front=t; 
        rear=front; 
    } 
    else{ 
            rear->next=t; 
            rear=t; 
            rear->next=NULL; 
        } 
} 
void queuefront(int *x,int *y) 
{ 
    *x=front->x; 
    *y=front->y; 
    return; 
} 
void dequeue() 
{ 
    node* t; 
    if(isEmpty()) 
    { 
        printf("Queue Underflow\n"); 
        return; 
    } 
    t=front; 
    front=t->next; 
    free(t); 
}
	IplImage* img;
int** blobDetection(IplImage *img,int *count) 
{ 
    int i,j,k,l,x,y; 
    *count=0; 
    int height = img->height; 
    int width = img->width; 
    int **visited; 
    visited = (int**)malloc(height*sizeof(int*)); 
    for(i=0;i<img->height;i++) 
        visited[i]=(int*)malloc(img->width*sizeof(int)); 
    for(i=0;i<img->height;i++) 
        for(j=0;j<img->width;j++) 
            visited[i][j]=-1; 
      
    for(i=1;i<img->height-1;i++) 
        for(j=1;j<img->width-1;j++) 
        { 
            if(PIX(img,i,j,0)==0) 
            {    
                if(visited[i][j]==-1) 
                { 
                    *count=*count +1; 
                    front=NULL; 
                    enqueue(i,j); 
                    queuefront(&x,&y); 
                    while(!isEmpty()) 
                    { 
                        queuefront(&x,&y); 
                        //printf("(%d,%d),(%d)",x,y,visited[x][y]); 
                        dequeue(); 
  
                        for(k=x-1;k<=x+1;k++) 
                            for(l=y-1;l<=y+1;l++) 
                            { 
                                if(PIX(img,k,l,0)==0 && visited[k][l]==-1) 
                                    { 
                                        enqueue(k,l); 
                                        visited[k][l]=*count; 
                                    } 
                            } 
                        visited[x][y]=*count; 
                    } 
  
                } 
  
            } 
        } 
        //printf("%d\n",*count); 
        return visited; 
}

void binary_convert(IplImage *img)
{
	int i,j;
	CvScalar pixel;
	for(i=0;i<img->height;i++)
	{
		for(j=0;j<img->width;j++)
		{
			pixel=cvGet2D(img,i,j);
			if(pixel.val[0]>100)
			{
				PIX(img,i,j,0)=255;
			}
			else
			{
				PIX(img,i,j,0)=0;
			}
		}
	}
	//cvNamedWindow("win",0);
	//cvShowImage("win",img);
	//cvWaitKey(0);
}

void centroid(int** output,int count)
{
	int i,j;
	double count_x[count+1];
	double count_y[count+1];
	double count_pixel[count+1];

	for(i=0;i<img->height;i++)
	{
		for(j=0;j<img->width;j++)
		{
			int value;
			value=output[i][j];
			if(value!=-1)
			{
				count_x[value]+=j;
				count_y[value]+=i;
				count_pixel[value]++;
			}
		}
	}
	for(i=1;i<count+1;i++)
	{
		count_x[i]/=count_pixel[i];
		count_y[i]/=count_pixel[i];
	}
	for(i=1;i<count+1;i++)
	{
		printf("For blob %d centroid is, x = %lf and y = %lf\n",i,count_x[i],count_y[i]);
		//count_y[i]/=count_pixel[i];
	}
}
int main()
{

	IplImage* out;
	int** output=NULL;
	int count=0;
	int i,j;
    	
	img=cvLoadImage("shapes.jpg",0);
	//out=cvCreateImage(cvGetSize(img),img->depth,1);
	
	binary_convert(img);                                //Convert image to binary

	output=blobDetection(img,&count);                   //Blob detection

	printf("count = %d\n",count);
	cvShowImage("window",img);
                                                         
	centroid(output,count);                             //Centroid Callback function
	
	cvWaitKey(0);
	return 0;
}