Papers › DiTAS: Quantizing Diffusion Transformers via Enhanced Activation Smoothing

DiTAS: Quantizing Diffusion Transformers via Enhanced Activation Smoothing

12 Sep 2024arXiv:2409.07756archive 2025-07-28

Zhenyuan Dong, Sai Qian Zhang

Diffusion Transformers (DiTs) have recently attracted significant interest from both industry and academia due to their enhanced capabilities in visual generation, surpassing the performance of traditional diffusion models that employ U-Net. However, the improved performance of DiTs comes at the expense of higher parameter counts and implementation costs, which significantly limits their deployment on resource-constrained devices like mobile phones. We propose DiTAS, a data-free post-training quantization (PTQ) method for efficient DiT inference. DiTAS relies on the proposed temporal-aggregated smoothing techniques to mitigate the impact of the channel-wise outliers within the input activations, leading to much lower quantization error under extremely low bitwidth. To further enhance the performance of the quantized DiT, we adopt the layer-wise grid search strategy to optimize the smoothing factor. Moreover, we integrate a training-free LoRA module for weight quantization, leveraging alternating optimization to minimize quantization errors without additional fine-tuning. Experimental results demonstrate that our approach enables 4-bit weight, 8-bit activation (W4A8) quantization for DiTs while maintaining comparable performance as the full-precision model.

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approx_standard_normal_cdf DZY122/DiTAS/diffusion/diffusion_utils.py official repository ran · our draft was wrong fingerprinted MIT (permissive) · d6a68e210556f857 · report
continuous_gaussian_log_likelihood DZY122/DiTAS/diffusion/diffusion_utils.py official repository ran · our draft was wrong MIT (permissive) · ab1c9568b4e13899 · report
create_logger DZY122/DiTAS/LinearQuant.py official repository ran · our draft was wrong MIT (permissive) · b2cc78f4103df806 · report
create_normal_map DZY122/DiTAS/utils_qaunt.py official repository ran MIT (permissive) · 98dc5039c3705609 · report
create_npz_from_sample_folder DZY122/DiTAS/sample_merge_TAS.py official repository ran · our draft was wrong MIT (permissive) · c43ca4c65f3079a7 · report
get_2d_sincos_pos_embed DZY122/DiTAS/models.py official repository ran · honoured contract MIT (permissive) · c92c27c924b517e8 · report
get_beta_schedule DZY122/DiTAS/diffusion/gaussian_diffusion.py official repository ran · honoured contract MIT (permissive) · 3e0fa4efc22272d4 · report
get_named_beta_schedule DZY122/DiTAS/diffusion/gaussian_diffusion.py official repository ran · honoured contract MIT (permissive) · 36e30c7fb679ec78 · report
low_rank_decomposition DZY122/DiTAS/LinearQuant.py official repository ran fingerprinted MIT (permissive) · 10cee608c936e97c · report
mean_flat DZY122/DiTAS/LinearQuant.py official repository ran · our draft was wrong fingerprinted MIT (permissive) · f6d7c009a8efb8b7 · report
modulate DZY122/DiTAS/models.py official repository ran · our draft was wrong fingerprinted MIT (permissive) · 03310bba324ae4fb · report
normal_kl DZY122/DiTAS/diffusion/diffusion_utils.py official repository ran · honoured contract fingerprinted MIT (permissive) · 8afbfc42c6ea0448 · report
space_timesteps DZY122/DiTAS/diffusion/respace.py official repository ran · fixture could not drive it MIT (permissive) · ea9dbc131adf582e · report
create_named_schedule_sampler DZY122/DiTAS/diffusion/timestep_sampler.py official repository unverified MIT (permissive) · e48218d7d73db0b3 · report
download_model DZY122/DiTAS/download.py official repository unverified MIT (permissive) · 6a0d5ecd441905cc · report
find_model DZY122/DiTAS/download.py official repository unverified MIT (permissive) · 29947a0a94157558 · report
get_2d_sincos_pos_embed_from_grid DZY122/DiTAS/models.py official repository unverified MIT (permissive) · 665d8a4e8f673a4c · report
quantize_tensor DZY122/DiTAS/utils_qaunt.py official repository unverified MIT (permissive) · 1b9176fa99542368 · report
weight_quant_fn DZY122/DiTAS/utils_qaunt.py official repository unverified MIT (permissive) · 588e216eef61e4b6 · report

Tasks

Image GenerationQuantization

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Methods

Diffusion

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