A ground-up technical course on diffusion models — the architecture behind modern image generators like Stable Diffusion. Starting from the intuition of adding and removing noise, it derives the forward process, the variational lower bound, the simplified training objective, the U-Net backbone, the DDPM training and sampling loops, fast deterministic samplers (DDIM), and finally conditioning and guidance.

Audience: technically comfortable; familiarity with deep learning recommended.
Prerequisites: Gaussian distributions, KL divergence, basic variational inference. The LLM course is a natural companion.


#Lesson
1The Big Picture
2The Forward Process
3The Reverse Process
4The Variational Lower Bound
5The Simplified Objective
6U-Net Architecture
7Training Algorithm
8DDPM Sampling
9DDIM and Score-Based Models
10Conditioning and Guidance

Appendices

AAcronyms
BFormulas & Symbol Glossary