H.264 compresses 300 frames into a fifth of the size of a single PNG frame

H.264 Is Magic

A technical walkthrough of H.264, the codec behind internet video, Blu-ray, phones, and drones. It starts with the raw bandwidth problem: 1080p at 60 Hz needs about 370 MB per second, filling a 50GB Blu-ray in two minutes. Then it explains the tricks — lossy quantization in the frequency domain, chroma subsampling, and motion compensation with I-, P-, and B-frames — that let a 300-frame video weigh less than one PNG screenshot.