A Deep Q-Network is a convolutional neural network which isn't something that I'm an expert in. But you can follow this article series by Intel to learn more about it. While you are reading that let's get to the cool results.

6 Minutes 57 Seconds Of AI Playing Flappy Bird

In case you are wondering what happened to the cute background; realize that Deep Q-Network use raw pixel values from the game to train itself. Removing the background saves a lot of time and computing resources. It's basically allowing the AI to have it easy and lazy to get faster results.