A lot of OpenCV functions are defined as

```
function(InputArray src, OutputArray dst, otherargs..)

```

So if I want to process and overwrite the same image, can I do this: 

```
function(myImg, myImg);

```

is it safe to do this way?

Thanks

Edit:
-----

I'm asking for the standard functions in OpenCV like `threshold`, `blur` etc. So I think they should have been implemented accordingly, right?