--- license: mit library_name: pytorch pipeline_tag: text-to-image tags: - image-generation - diffusion - pixel-space - adaptive-tokenization - imagenet - text-to-image - one-step-generation ---

BudgetPix: Compute-Adaptive Tokenization for Pixel-Space Image Diffusion

arXiv Project page Paper PDF Code on GitHub

BudgetPix teaser: one text-to-image model run from 100 % down to 10 % of the tokens

Checkpoints of the public reimplementation of **BudgetPix**. Pixel-space diffusion transformers spend the same compute on flat sky as on a face; BudgetPix lets one model run at many compute budgets. An entropy quadtree merges flat regions of the image into coarser tokens, the backbone runs on the shorter sequence, and a small token-local refiner puts the detail back inside each merged token. Every added module is zero-initialised, so the adapted model starts as the released model; at inference a single checkpoint is driven with a token budget. The code that loads, samples from and trains these files is at https://github.com/budgetpix/BudgetPix-public. Every file is the inference-only EMA weights of the full adapted model (released backbone plus the added modules) in fp32, with the geometry and trainer arguments it was trained with. | file | model | task | resolution | dense tokens | size | |---|---|---|---|---|---| | `budgetpix_jit_b16_256.pth` | JiT-B/16 | class-conditional ImageNet | 256 | 256 | 0.53 GB | | `budgetpix_jit_b32_512.pth` | JiT-B/32 | class-conditional ImageNet | 512 | 256 | 0.54 GB | | `budgetpix_jit_l16_256.pth` | JiT-L/16 | class-conditional ImageNet | 256 | 256 | 1.85 GB | | `budgetpix_jit_l32_512.pth` | JiT-L/32 | class-conditional ImageNet | 512 | 256 | 1.86 GB | | `budgetpix_minit2i_b_512.pt` | MiniT2I-B/16 | text-to-image | 512 | 1024 | 1.04 GB | | `budgetpix_minit2i_l_512.pt` | MiniT2I-L/16 | text-to-image | 512 | 1024 | 3.66 GB | | `budgetpix_pixeldit_1024.pt` | PixelDiT-T2I 1.3B | text-to-image | 1024 | 4096 | 5.23 GB | | `budgetpix_pmf_l16_256.pt` | pMF-L/16 | one-step class-conditional ImageNet | 256 | 256 | 2.07 GB | Extras for the pMF line: `pmf_released_B16_full_uv.pt` and `pmf_released_L16_full_uv.pt` are the released pixel MeanFlow weights ([Lyy0725/pMF](https://huggingface.co/Lyy0725/pMF), MIT) converted to PyTorch with the auxiliary v-branch that fine-tuning needs; the Hub's inference files carry the u-path only. `SHA256SUMS` lists the hash of every file. ## Usage ```bash git clone https://github.com/budgetpix/BudgetPix-public && cd BudgetPix-public pip install -r requirements.txt python scripts/download_checkpoints.py --all # fetches from this repo and checks the hashes cd jit && python sample.py --ckpt ../checkpoints/budgetpix_jit_l32_512.pth --budget 128 --classes 207,88,417,933 --overlay ``` The MiniT2I, PixelDiT and pMF lines import the official PyTorch code of those models at run time (`MINIT2I_ROOT`, `PIXELDIT_ROOT`, `PMF_ROOT`); the text encoders (`google/flan-t5-large`, `Efficient-Large-Model/gemma-2-2b-it`) are downloaded from the Hub on first use. See the GitHub README for sampling, training and evaluation commands. ## License The JiT, MiniT2I and pMF checkpoints derive from MIT-licensed weights and are released under MIT. The PixelDiT checkpoint derives from NVIDIA's released PixelDiT weights and is subject to the [NVIDIA License (NSCLv1)](https://github.com/NVlabs/PixelDiT/blob/master/LICENSE), which permits non-commercial research use only. ## Citation ```bibtex @article{kara2026budgetpix, title={BudgetPix: Compute-Adaptive Tokenization for Pixel-Space Image Diffusion}, author={Ozgur Kara and Yujia Chen and Daniel Watson and David Forsyth and James Matthew Rehg and Wen-Sheng Chu and Du Tran}, journal={arXiv preprint arXiv:2610.12307}, year={2026} } ```