Papers › Improved Vector Quantized Diffusion Models

Improved Vector Quantized Diffusion Models

31 May 2022arXiv:2205.16007archive 2025-07-28

Zhicong Tang, Shuyang Gu, Jianmin Bao, Dong Chen, Fang Wen

Vector quantized diffusion (VQ-Diffusion) is a powerful generative model for text-to-image synthesis, but sometimes can still generate low-quality samples or weakly correlated images with text input. We find these issues are mainly due to the flawed sampling strategy. In this paper, we propose two important techniques to further improve the sample quality of VQ-Diffusion. 1) We explore classifier-free guidance sampling for discrete denoising diffusion model and propose a more general and effective implementation of classifier-free guidance. 2) We present a high-quality inference strategy to alleviate the joint distribution issue in VQ-Diffusion. Finally, we conduct experiments on various datasets to validate their effectiveness and show that the improved VQ-Diffusion suppresses the vanilla version by large margins. We achieve an 8.44 FID score on MSCOCO, surpassing VQ-Diffusion by 5.42 FID score. When trained on ImageNet, we dramatically improve the FID score from 11.89 to 4.83, demonstrating the superiority of our proposed techniques.

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all_gather microsoft/vq-diffusion/image_synthesis/distributed/distributed.py official repository ran MIT (permissive) · 5d1755bb165b0225 · report
all_reduce microsoft/vq-diffusion/image_synthesis/distributed/distributed.py official repository ran MIT (permissive) · 68d08cf984f9fe2d · report
log_1_min_a microsoft/vq-diffusion/image_synthesis/modeling/transformers/diffusion_transformer.py official repository ran · honoured contract fingerprinted MIT (permissive) · 479771b269fc5883 · report
log_add_exp microsoft/vq-diffusion/image_synthesis/modeling/transformers/diffusion_transformer.py official repository ran · honoured contract fingerprinted MIT (permissive) · 032c0dece6594020 · report
reduce_dict microsoft/vq-diffusion/image_synthesis/distributed/distributed.py official repository ran MIT (permissive) · 7dbdda0920e3d074 · report
sum_except_batch microsoft/vq-diffusion/image_synthesis/modeling/transformers/diffusion_transformer.py official repository ran · our draft was wrong fingerprinted MIT (permissive) · 5eb945b1f970f6af · report

Tasks

DenoisingImage Generation

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Methods

Diffusion

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