its impossible. If you have an image with low quality the best you can do is maybe apply some kind of sharpening filter to get details back. But garbage in garbage out! if you start with something that is low. It cant really get better without adding information the original image did not have present. Photoshop would be the application that would allow you the best chance of enhancing and up-resing a photo. Depending on the level of degredation you may be able to enhance the image with a filter. In other cases you may have alot of work ahead of you to restore the image. In that case you would need to manually enhance and add information to the image in an artistic way.
