I would select the photo using Adobe' Reader's snapshot tool (should be on the toolbar, or tools--basic--snapshot)); copy it to a picture editing program (or at worst Microsoft Paint); then choose to save it as a JPG.
To add to dr b; If you click the snapshot tool (small camera) to activate it and click anywhere on the page it will save the whole page to clipboard. To save a separate image you need to 'range' it (click in the top left corner of the image and drag to the right bottom. When you let the mouse button go you'll get a popup telling you it is saved to clipboard.
You can then view your clipboard by pasting it into Irfanview or any program that will let you paste the clipboard content.