You can do this in the studio, in one of 2 ways.
First way is to place an image in the work area. Then you grab the middle handle of the picture by clicking your left mouse button and holding down on it and pull in the opposite way until done, then let go of the mouse button.
The other way is hold down the ALT button on your keyboard while doing the above instructions. This essentially flips the image in place.
If you want to do a mirror image, just copy the image and put it on the other side and flip it.
Watch the video to see this (No Sound).