Rescent Advances in Deep Generative Model (4/4) - Score-Based Generative Modeling through Stochastic Differential Equations (SDE) (Connection to Diffusion Models)


< 목차 >


본 post 는 앞선 score matching post 와 마찬가지로 Score-Based Generative Modeling through Stochastic Differential Equations (SDE) 논문과 해당 논문의 저자 Yang SongBlog PostSeminar Video를 기반으로 해서 작성 했습니다.

Motivation

앞선 Post 들을 통해 우리는 다른 Generative Model 들과 Score Matching Models 을 비교해보며 어떤 차이가 있는지에 대해 알아봤습니다.

Perturbing data with an SDE

perturb_vp Fig.

Stochastic Process

Ordinary Differential Equation (ODE) and Stochastic Differential Equation (SDE)

Reversing the SDE for sample generation

denoise_vp Fig.

sde_schematic Fig.

Estimating the reverse SDE with score-based models and score matching

How to solve the reverse SDE

Probability flow ODE

teaser Fig.

Controllable generation for inverse problem solving

Connection to Diffusion Models and Others

Denoising Diffusion Implicit Models (DDIM)

Challenges of Score-based Models

  • First, the sampling speed is slow since it involves a large number of Langevin-type iterations.
  • Second, it is inconvenient to work with discrete data distributions since scores are only defined on continuous distributions.

References