If you wrote numbers or letters as precisely as the triangles are drawn in the example, I doubt computers would have much of a problem reading them. We've got fast algorithms for digit classification that are pretty much perfect on the MNIST dataset with just 0.21% error (and I'm pretty sure there are errors in the dataset itself, which brings the real error rate down). MNIST is an easy image recognition task compared to others but it's not done with clearly written numbers.

Here's an example of some that were misclassified by an algorithm: http://www.concordia.ca/content/concordia/en/research/cenpar...