Is there any way to convert a Bitmap back to an EncodedImage in order to scale it?

I have a large bitmap created from an EncodedImage. I scaled it fine and displayed it. The next step is to draw the same bitmap starting at a specified x and y, but I need to scale it too. The drawBitmap allows me to draw starting at a specified destination (ie. x,y) but the scaling is part of the EncodedImage. How do I translate the portion of the bitmap back to an Image in order to scale it?
Or is there another way to do this.

Any help will be appreciated.

Thanks