Obviously you'd have to have Photoshop installed for Virendra's answer to work.
Thing is, alot of folks do not have Photoshop installed.
How to select an Image Editor:
Go into Acrobat Pro's Preferences.
Select the "Touchup" category.
At the top of the dialog observe "Image Editor".
Click the button "Choose Image Editor".
Note that IF you have Photoshop installed then, with the install of Acrobat, Photoshop is selected by default.
So, you browse to the executable for the desired Image Editor.
Aside from Photoshop you could try Inkscape, Photoshop Elements or the desktop download of Picasa.
There may be others - you'd have to do trial and error to see what "takes".