Latent Diffusion Models

arXiv | BibTeX

High-Resolution Image Synthesis with Latent Diffusion Models
Robin Rombach*, Andreas Blattmann*, Dominik Lorenz, Patrick Esser, Björn Ommer
* equal contribution

Requirements

A suitable conda environment named ldm can be created and activated with:

conda env create -f environment.yaml
conda activate ldm

Model Zoo

Pretrained Autoencoding Models

Model	FID vs val	PSNR	PSIM	Link	Comments
f=4, VQ (Z=8192, d=3)	0.58	27.43 +/- 4.26	0.53 +/- 0.21	https://ommer-lab.com/files/latent-diffusion/vq-f4.zip
f=4, VQ (Z=8192, d=3)	1.06	25.21 +/- 4.17	0.72 +/- 0.26	https://heibox.uni-heidelberg.de/f/9c6681f64bb94338a069/?dl=1	no attention
f=8, VQ (Z=16384, d=4)	1.14	23.07 +/- 3.99	1.17 +/- 0.36	https://ommer-lab.com/files/latent-diffusion/vq-f8.zip
f=8, VQ (Z=256, d=4)	1.49	22.35 +/- 3.81	1.26 +/- 0.37	https://ommer-lab.com/files/latent-diffusion/vq-f8-n256.zip
f=16, VQ (Z=16384, d=8)	5.15	20.83 +/- 3.61	1.73 +/- 0.43	https://heibox.uni-heidelberg.de/f/0e42b04e2e904890a9b6/?dl=1

f=4, KL	0.27	27.53 +/- 4.54	0.55 +/- 0.24	https://ommer-lab.com/files/latent-diffusion/kl-f4.zip
f=8, KL	0.90	24.19 +/- 4.19	1.02 +/- 0.35	https://ommer-lab.com/files/latent-diffusion/kl-f8.zip
f=16, KL (d=16)	0.87	24.08 +/- 4.22	1.07 +/- 0.36	https://ommer-lab.com/files/latent-diffusion/kl-f16.zip
f=32, KL (d=64)	2.04	22.27 +/- 3.93	1.41 +/- 0.40	https://ommer-lab.com/files/latent-diffusion/kl-f32.zip

Get the models

Running the following script downloads und extracts all available pretrained autoencoding models.

bash scripts/download_first_stages.sh

The first stage models can then be found in models/first_stage_models/<model_spec>

Training autoencoder models

Configs for training a KL-regularized autoencoder on ImageNet are provided at configs/autoencoder. Training can be started by running

CUDA_VISIBLE_DEVICES=<GPU_ID> python main.py --base configs/autoencoder/<config_spec> -t --gpus 0,

where config_spec is one of {autoencoder_kl_8x8x64.yaml(f=32, d=64), autoencoder_kl_16x16x16.yaml(f=16, d=16), autoencoder_kl_32x32x4(f=8, d=4), autoencoder_kl_64x64x3(f=4, d=3)}.

For training VQ-regularized models, see the taming-transformers repository.

Pretrained LDMs

Datset	Task	Model	FID	IS	Prec	Recall	Link	Comments
CelebA-HQ	Unconditional Image Synthesis	LDM-VQ-4 (200 DDIM steps, eta=0)	5.11 (5.11)	3.29	0.72	0.49	https://ommer-lab.com/files/latent-diffusion/celeba.zip
FFHQ	Unconditional Image Synthesis	LDM-VQ-4 (200 DDIM steps, eta=1)	4.98 (4.98)	4.50 (4.50)	0.73	0.50	https://ommer-lab.com/files/latent-diffusion/ffhq.zip
LSUN-Churches	Unconditional Image Synthesis	LDM-KL-8 (400 DDIM steps, eta=0)	4.02 (4.02)	2.72	0.64	0.52	https://ommer-lab.com/files/latent-diffusion/lsun_churches.zip
LSUN-Bedrooms	Unconditional Image Synthesis	LDM-VQ-4 (200 DDIM steps, eta=1)	2.95 (3.0)	2.22 (2.23)	0.66	0.48	https://ommer-lab.com/files/latent-diffusion/lsun_bedrooms.zip
ImageNet	Class-conditional Image Synthesis	LDM-VQ-8 (200 DDIM steps, eta=1)	7.77(7.76)* /15.82**	201.56(209.52)* /78.82**	0.84* / 0.65**	0.35* / 0.63**	https://ommer-lab.com/files/latent-diffusion/cin.zip	: w/ guiding, classifier_scale 10 *: w/o guiding, scores in bracket calculated with script provided by ADM
Conceptual Captions	Text-conditional Image Synthesis	LDM-VQ-f4 (100 DDIM steps, eta=0)	16.79	13.89	N/A	N/A	https://ommer-lab.com/files/latent-diffusion/text2img.zip	finetuned from LAION
OpenImages	Super-resolution	N/A	N/A	N/A	N/A	N/A	https://ommer-lab.com/files/latent-diffusion/sr_bsr.zip	BSR image degradation
OpenImages	Layout-to-Image Synthesis	LDM-VQ-4 (200 DDIM steps, eta=0)	32.02	15.92	N/A	N/A	https://ommer-lab.com/files/latent-diffusion/layout2img_model.zip
Landscapes (finetuned 512)	Semantic Image Synthesis	LDM-VQ-4 (100 DDIM steps, eta=1)	N/A	N/A	N/A	N/A	https://ommer-lab.com/files/latent-diffusion/semantic_synthesis.zip

Get the models

The LDMs listed above can jointly be downloaded and extracted via

bash scripts/download_models.sh

The models can then be found in models/ldm/<model_spec>.

Sampling with unconditional models

We provide a first script for sampling from our unconditional models. Start it via

CUDA_VISIBLE_DEVICES=<GPU_ID> python scripts/sample_diffusion.py -r models/ldm/<model_spec>/model.ckpt -l <logdir> -n <\#samples> --batch_size <batch_size> -c <\#ddim steps> -e <\#eta>

Inpainting

Download the pre-trained weights

wget -O models/ldm/inpainting_big/last.ckpt https://heibox.uni-heidelberg.de/f/4d9ac7ea40c64582b7c9/?dl=1

and sample with

python scripts/inpaint.py --indir data/inpainting_examples/ --outdir outputs/inpainting_results

indir should contain images *.png and masks <image_fname>_mask.png like the examples provided in data/inpainting_examples.

Coming Soon...

Code for training LDMs and the corresponding compression models.
Inference scripts for conditional LDMs for various conditioning modalities.
In the meantime, you can play with our colab notebook https://colab.research.google.com/drive/1xqzUi2iXQXDqXBHQGP9Mqt2YrYW6cx-J?usp=sharing
We will also release some further pretrained models.

Comments

Our codebase for the diffusion models builds heavily on OpenAI's codebase and https://github.com/lucidrains/denoising-diffusion-pytorch. Thanks for open-sourcing!
The implementation of the transformer encoder is from x-transformers by lucidrains.

BibTeX

@misc{rombach2021highresolution,
      title={High-Resolution Image Synthesis with Latent Diffusion Models}, 
      author={Robin Rombach and Andreas Blattmann and Dominik Lorenz and Patrick Esser and Björn Ommer},
      year={2021},
      eprint={2112.10752},
      archivePrefix={arXiv},
      primaryClass={cs.CV}
}