Lossy compression is incredibly mathy and complex, but fascinating to read about. If you liked today's comic, and want a deeper understanding, pop over to EE Times for a real step-by-step. It's amazing how quickly the algorithm reveals itself when you look closely at a heavily compressed JPEG. Funnily, the one time I actually want jpeg artifacts, I had the hardest time producing them. Much of this is because of the nature of lossy and my art style. Lossy handles flat gradients pretty well, so I had the hardest time getting a good example of color distortion, while the hard line contrasts produced tons of ringing.