How does card.io image processing work?

Question

How do services like card.io work behind the scenes? Do they use an OCR library like Tesseract or is it more complex?

Also, in this video, it looks like the app is waiting for you to hold your card in a specific range from the camera inside the green boundaries on the camera, and when you do it takes the photo automatically. If the image recognition is happening on the server, how did they do that?

How can I implement my own mobile 2D object scanner? Where do I start?

Answer 1

Josh from card.io here. I can't tell you the details of how card.io works (hopefully others will speculate here), but I can answer some of your other questions.

card.io does not use an OCR engine; we looked at Tesseract and others and found that they did not work well on many credit cards.

card.io's image recognition happens entirely on the phone. Early versions required some server assistance, but even those did a good chunk of the work on the phone.

To get started, I recommend sitting down and reading Learning OpenCV; it is a good general introduction to computer vision. Then play around and ask more detailed questions. On the machine learning side, Theano and Eigen are very helpful libraries.