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Diffusion Models

Generative models that create data by learning to reverse a gradual noising process, behind most modern image generation and now text.

exploring mlgenerativetheory

Diffusion models generate data by starting from noise and denoising it step by step. Training teaches the model to reverse a process that slowly adds noise to real data, so sampling walks that process backward, from pure noise to a coherent result.

Why I’m digging in

  • They are the engine behind modern image, audio, and video generation, and the underlying math is genuinely elegant.
  • Diffusion is now being applied to text (diffusion language models), a fascinating alternative to autoregressive generation.

What I want to understand

  • The forward and reverse process, and the intuition behind score matching.
  • DDPM versus DDIM sampling, and why latent diffusion (Stable Diffusion) made it practical.
  • Classifier-free guidance, and how conditioning (text to image) actually works.
  • How diffusion for text compares to autoregressive LLMs.

Starting points

  • The DDPM paper (Ho et al.) and Lilian Weng’s “What are Diffusion Models?” write-up.
  • The latent diffusion / Stable Diffusion paper.
  • Hugging Face diffusers to run and take apart a pipeline.

Notes