[Add image inside selection]

Hi all, 

I have created a black figure from the photo of a woman, and I am now trying to fill the figure with an image of flowers. Usually, to add an image inside a shape I just place the image on top on the shape and then move it in the layers. However here it seems to take the background of the figure as part of the image, so when I move my image of flowers in the layer area to put it inside the figure of the woman, it replaces the entire surface (figure itself + background of the figure). I have exported my figure without background as an eps file to try and work around but that gave me the same result.

I believe converting the figure into a shape would do the trick but I couldn't find how to do this, I'm not even sure it's possible because I couldn't find any post on this topic.

Any idea? Thanks a lot!