How to extract numbers from an image?

I want to be able to take an image of some numbers, and have my MacBook "look" at the image and extract what the numbers are that are there (this is so I can do some algorithms with the numbers). Is this only possible with iPad handwriting recognition software?

I actually want to do this entirely on my MacBook though. So basically again, I want to get the important number from an image, and convert it into a computer number. I can then plug that number into Excel and do various things with it to perform calculations, which is what I really want to do. Any ideas? Thanks.