# How can I get Back Projection matrix including numbers over 255 or decimal by calcBackProject?

Hi, I need to use *calcBackProject* and then display the exact number.

```
for ( int i = 0; i < backProj.rows; ++i )
{
for ( int j = 0; j < backProj.cols; ++j )
{
cout << int(backProj.at< uchar >( i, j )) << " ";
}
cout << endl;
}
```

But its max value is 255 because of "uchar". I tried to use

```
Mat backProj( slid_.rows, slid_.cols, CV_64FC1 );
```

After using *calcBackProject*, display it

```
cout << backProj.at< double >( i, j );
```

but it does not work.

I really need the exact numbers which are bigger than 255. I don't want to use *normalize* before. Can I make it by *calcBackProject*?

If I try to **scale it down**, can this Back Projection matrix includes decimal? Because I don't want that 0 exists in this matrix.

Thank you.