Im trying to do my coding modifying the myfunc.c
Im always getting the same value.
 
what I do(problably wrong) is to get a frame, calculate the differences and then check if the yuv values are over a given threshold.
 
heres part of the code
 
void myfunc() {
   unsigned int  ix,xx, yy, y1, u1, v1, sumx, sumy;
   
    unsigned char *frame_buf;
    y1 = u1=v1 =xx=0; yy=0;  sumx=0; sumy =0;
    grab_reference_frame() ;
    move_image((unsigned char *)DMA_BUF1, (unsigned char *)DMA_BUF2, (unsigned char *)FRAME_BUF, imgWidth, imgHeight);
    compute_frame_diff((unsigned char *)FRAME_BUF,  (unsigned char *)FRAME_BUF2, imgWidth, imgHeight);  
     
   
 for (xx=0; xx<imgWidth; xx+=2) {    
       for (yy=0; yy<imgHeight; yy++) {
       ix = index(xx,yy);  
           y1 = (((unsigned int)frame_buf[ix+1] + (unsigned int)frame_buf[ix+3]));
           u1 = ((unsigned int)frame_buf[ix]);
           v1 = ((unsigned int)frame_buf[ix+2]);
           
           if(y1+u1+v1> 80){
               sumx=sumx+1;}          
                         
         
       }
    }
    printf(" %x", sumx);
     
    return;
}
 
thanks

 need to create a char pointer and initialize it to frame_buf or frame_buf2
right?
   
    unsigned char *frame_buf, *frame_buf2;
    frame_buf = FRAME_BUF;
    frame_buf2 = FRAME_BUF2;

i still get the same value, i think im doing sth wrong here. Should i use grab_frame or grab_referece frame again?
 
extern unsigned int imgWidth, imgHeight;
 
void myfunc() {
   unsigned int  ix,xx, yy, y1, u1, v1, sumx, sumy;
  
    unsigned char *frame_buf, *frame_buf2;
    frame_buf = FRAME_BUF;
    frame_buf2 = FRAME_BUF2;
    y1 = u1=v1 =xx=0; yy=0;  sumx=0; sumy =0;
    grab_reference_frame() ;
    move_image((unsigned char *)DMA_BUF1, (unsigned char *)DMA_BUF2, (unsigned char *)FRAME_BUF, imgWidth, imgHeight);
    move_image((unsigned char *)DMA_BUF1, (unsigned char *)DMA_BUF2, (unsigned char *)FRAME_BUF2, imgWidth, imgHeight);
    compute_frame_diff((unsigned char *)FRAME_BUF,  (unsigned char *)FRAME_BUF2, imgWidth, imgHeight);  
        
 for (xx=0; xx<imgWidth; xx+=2) {    
        for (yy=0; yy<imgHeight; yy++) {
        ix = index(xx,yy);  
            y1 = (((unsigned int)frame_buf[ix+1] + (unsigned int)frame_buf[ix+3]));
            u1 = ((unsigned int)frame_buf[ix]);
            v1 = ((unsigned int)frame_buf[ix+2]);
            
            if(y1+u1+v1> 80){
                sumx=sumx+1;}          
        }
    }
    printf(" %u", sumx);
    
    return;
}

Yes, that was what i saw. i modified the code and it works.
Now i want to get the centroid but i get strange values when i print the division of 2 unsigned ints.
how could i just print it out without decimal number. i just want the values that are before of the point.
 
thanks

here is the code. i get strange values.
 
void myfunc() {
   unsigned int  ix,xx, yy, y1, u1, v1, sumx, sumy,totalpix, centerx,centery;
   
    unsigned char *frame_buf, *frame_buf2;
   frame_buf = FRAME_BUF;
    frame_buf2 = FRAME_BUF2;
     
    // grab_frame() ;
     
   while(1){
    grab_reference_frame() ;
    compute_frame_diff((unsigned char *)FRAME_BUF,  (unsigned char *)FRAME_BUF2, imgWidth, imgHeight);  
  //  move_image((unsigned char *)DMA_BUF1, (unsigned char *)DMA_BUF2, (unsigned char *)FRAME_BUF, imgWidth, imgHeight);
    //move_image((unsigned char *)DMA_BUF1, (unsigned char *)DMA_BUF2, (unsigned char *)FRAME_BUF2, imgWidth, imgHeight);
    //compute_frame_diff((unsigned char *)FRAME_BUF,  (unsigned char *)FRAME_BUF2, imgWidth, imgHeight);  
      y1 = u1=v1 =xx=0; yy=0;  centerx=centery=totalpix =sumx=0; sumy =0;
 for (xx=0; xx<imgWidth; xx+=2) {    
       for (yy=0; yy<imgHeight; yy++) {
       ix = index(xx,yy);  
           y1 = (((unsigned int)frame_buf[ix+1] + (unsigned int)frame_buf[ix+3]));
           u1 = ((unsigned int)frame_buf[ix]);
           v1 = ((unsigned int)frame_buf[ix+2]);
           
           if(y1>80 && u1> 30 && v1> 30){
              sumx=sumx+xx;      
              sumy=sumy+yy;    
              totalpix=totalpix+1;
      /* printf(" %u", y1);*/ }
    }}
    centerx=sumx/totalpix;  
    centery=sumy/totalpix;
    if (sumx>0 && sumy>0){printf(" &&& x:%u y:%u totalpix:%u  &&&",centerx,centery,totalpix );}
   
    move_image((unsigned char *)DMA_BUF1, (unsigned char *)DMA_BUF2, (unsigned char *)FRAME_BUF, imgWidth, imgHeight)  ;
    }return;

I would like to compare 2 consecutive frames.
for example eve 20 seconds.  
How could i store Frame_BUF into FRAME_BUF2 and from there compare the differences
then capture a new frame and store it in Frame_BUF and compare it to FRAME_BUF2.
this way i only need to take one picture not 2 .

I didnt find the copy_image() function so i used  
 
memcpy(FRAME_BUF,FRAME_BUF2,sizeof(imgWidth * imgHeight * 2));
 
 
but seems its not working.
 
void myfunc() {
   unsigned int  ix,xx, yy, y1, u1, v1, sumx, sumy,totalpix, centerx,centery;
   
    unsigned char *frame_buf, *frame_buf2;
   frame_buf = FRAME_BUF;
    frame_buf2 = FRAME_BUF2;
     
     grab_frame() ;
     
   while(1){
    grab_reference_frame() ;
    compute_frame_diff((unsigned char *)FRAME_BUF,  (unsigned char *)FRAME_BUF2, imgWidth, imgHeight);  
   
     
      y1 = u1=v1 =xx=0; yy=0;  centerx=centery=totalpix =sumx=0; sumy =0;
 for (xx=0; xx<imgWidth; xx+=2) {    
       for (yy=0; yy<imgHeight; yy++) {
       ix = index(xx,yy);  
           y1 = (((unsigned int)frame_buf[ix+1] + (unsigned int)frame_buf[ix+3]));
           u1 = ((unsigned int)frame_buf[ix]);
           v1 = ((unsigned int)frame_buf[ix+2]);
           
           if(y1>80 && u1> 30 && v1> 30){
              sumx=sumx+xx;      
              sumy=sumy+yy;    
              totalpix=totalpix+1;
      /* printf(" %u", y1);*/ }
    }}
    centerx=sumx/totalpix;  
    centery=sumy/totalpix;
    if (sumx>0 && sumy>0){printf(" &&& x:%u y:%u totalpix:%u  &&&",centerx,centery,totalpix );}
   
    memcpy(FRAME_BUF,FRAME_BUF2,sizeof(imgWidth * imgHeight * 2));
    }return;
     
     
}

Is there any way to control the frames per second so it could work, or with the use of a timer.
I would like  at most to capture 8 frames per second. How could i do this?