README.md

VQGAN-f16-16384

Model Description

This is a Pytorch Lightning checkpoint of VQGAN, which learns a codebook of context-rich visual parts by leveraging both the use of convolutional methods and transformers. It was introduced in Taming Transformers for High-Resolution Image Synthesis (CVPR paper).

The model allows the encoding of images as a fixed-length sequence of tokens taken from the codebook.

This version of the model uses a reduction factor f=16 and a vocabulary of 13,384 tokens.

As an example of how the reduction factor works, images of size 256x256 are encoded to sequences of 256 tokens: 256/16 * 256/16. Images of 512x512 would result in sequences of 1024 tokens.

Datasets Used for Training

• ImageNet. We didn't train this model from scratch. Instead, we started from a checkpoint pre-trained on ImageNet.
• Conceptual Captions 3M (CC3M).
• OpenAI subset of YFCC100M.

We fine-tuned on CC3M and YFCC100M to improve the encoding quality of people and faces, which are not very well represented in ImageNet. We used a subset of 2,268,720 images from CC3M and YFCC100M for this purpose.

Training Process

Finetuning was performed in PyTorch using taming-transformers. The full training process and model preparation includes these steps:

• Pre-training on ImageNet. Previously performed. We used this checkpoint.
• Fine-tuning, Part 1.
• Fine-tuning, Part 2 – continuation from Part 1. The final checkpoint has been logged as an artifact in the training run and is the model present in this card.
• Conversion to JAX as flax-community/vqgan_f16_16384.

How to Use

The checkpoint can be loaded using Pytorch-Lightning.

Note: omegaconf==2.0.0 is required for loading the checkpoint.

Related Models in the Hub

• JAX version of VQGAN, trained on the same datasets described here: flax-community/vqgan_f16_16384.
• DALL·E mini, a Flax/JAX simplified implementation of OpenAI's DALL·E.

Other

This model was successfully used as part of the implementation of DALL·E mini. Our report contains more details on how to leverage it in an image encoding / generation pipeline.