Papers › Causal Diffusion Transformers for Generative Modeling

Causal Diffusion Transformers for Generative Modeling

16 Dec 2024arXiv:2412.12095archive 2025-07-28

Chaorui Deng, Deyao Zhu, Kunchang Li, Shi Guang, Haoqi Fan

We introduce Causal Diffusion as the autoregressive (AR) counterpart of Diffusion models. It is a next-token(s) forecasting framework that is friendly to both discrete and continuous modalities and compatible with existing next-token prediction models like LLaMA and GPT. While recent works attempt to combine diffusion with AR models, we show that introducing sequential factorization to a diffusion model can substantially improve its performance and enables a smooth transition between AR and diffusion generation modes. Hence, we propose CausalFusion - a decoder-only transformer that dual-factorizes data across sequential tokens and diffusion noise levels, leading to state-of-the-art results on the ImageNet generation benchmark while also enjoying the AR advantage of generating an arbitrary number of tokens for in-context reasoning. We further demonstrate CausalFusion's multimodal capabilities through a joint image generation and captioning model, and showcase CausalFusion's ability for zero-shot in-context image manipulations. We hope that this work could provide the community with a fresh perspective on training multimodal models over discrete and continuous data.

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Syntology Ran 8 of 10 code samples harvested from 1 repository linked to this paper; 2 have no recorded run. Of those that ran: 1 ran · honoured contract; 1 ran · our draft was wrong; 1 ran · fixture could not drive it; 5 ran with no contract checked.

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causalfusion/causalfusion officialmentioned in papermentioned on GitHubpytorch report

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1ran · honoured contract
1ran · our draft was wrong
1ran · fixture could not drive it
5ran
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Block causalfusion/causalfusion/models.py official repository ran · metamorphic tier: deterministic no licence file found · pointer only · b6fa5ad782b68160 · report
GeneralizedCausalAttention causalfusion/causalfusion/models.py official repository ran no licence file found · pointer only · 322790a68139c0a3 · report
LabelEmbedder causalfusion/causalfusion/models.py official repository ran · metamorphic tier: deterministic no licence file found · pointer only · 19b85a064360126a · report
Mlp causalfusion/causalfusion/models.py official repository ran · metamorphic tier: deterministic no licence file found · pointer only · 853c1fff1fdf9ee8 · report
TimestepEmbedder causalfusion/causalfusion/models.py official repository ran · metamorphic tier: invariant fingerprinted no licence file found · pointer only · 7a14af05d7f12417 · report
create_npz_from_sample_folder causalfusion/causalfusion/sample.py official repository ran · our draft was wrong no licence file found · pointer only · 84e2a647a1c4db79 · report
get_2d_sincos_pos_embed causalfusion/causalfusion/models.py official repository ran · honoured contract no licence file found · pointer only · 95e24bd9e56b2417 · report
CausalDiffusionModel causalfusion/causalfusion/models.py official repository unverified no licence file found · pointer only · fa3b06d978b9c137 · report
get_1d_sincos_pos_embed_from_grid identical code first harvested elsewhere ran · fixture could not drive it fingerprinted licence of this copy not recorded · e5947aba1d10885f · report
get_2d_sincos_pos_embed_from_grid identical code first harvested elsewhere unverified licence of this copy not recorded · 665d8a4e8f673a4c · report

Tasks

DecoderImage Generation

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Methods

AdamAttentionAttention DropoutBPECosine AnnealingDense ConnectionsDiffusionDiscriminative Fine-TuningDropoutGPTLLaMALayer NormalizationLinear LayerLinear Warmup With Cosine AnnealingMulti-Head AttentionResidual ConnectionSoftmaxWeight Decay

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