BK-SDM-2M Model Card

BK-SDM-{Base-2M, Small-2M, Tiny-2M} are pretrained with 10× more data (2.3M LAION image-text pairs) compared to our previous release.

• Block-removed Knowledge-distilled Stable Diffusion Model (BK-SDM) is an architecturally compressed SDM for efficient text-to-image synthesis.
• The previous BK-SDM-{Base, Small, Tiny} were obtained via distillation pretraining on 0.22M LAION pairs.
• Resources for more information: Paper, GitHub, Demo.

Examples with 🤗Diffusers library.

An inference code with the default PNDM scheduler and 50 denoising steps is as follows.

import torch
from diffusers import StableDiffusionPipeline

pipe = StableDiffusionPipeline.from_pretrained("nota-ai/bk-sdm-small-2m", torch_dtype=torch.float16)
pipe = pipe.to("cuda")

prompt = "a black vase holding a bouquet of roses"
image = pipe(prompt).images[0]  
    
image.save("example.png")

Compression Method

Adhering to the U-Net architecture and distillation pretraining of BK-SDM, the difference in BK-SDM-2M is a 10× increase in the number of training pairs.

• Training Data: 2,256,472 image-text pairs (i.e., 2.3M pairs) from LAION-Aesthetics V2 6.25+.
• Hardware: A single NVIDIA A100 80GB GPU
• Gradient Accumulations: 4
• Batch: 256 (=4×64)
• Optimizer: AdamW
• Learning Rate: a constant learning rate of 5e-5 for 50K-iteration pretraining

Experimental Results

The following table shows the zero-shot results on 30K samples from the MS-COCO validation split. After generating 512×512 images with the PNDM scheduler and 25 denoising steps, we downsampled them to 256×256 for evaluating generation scores.

• Our models were drawn at the 50K-th training iteration.

Effect of Different Data Sizes for Training BK-SDM-Small

Increasing the number of training pairs improves the IS and CLIP scores over training progress. The MS-COCO 256×256 30K benchmark was used for evaluation.

Furthermore, with the growth in data volume, visual results become more favorable (e.g., better image-text alignment and clear distinction among objects).

Additional Visual Examples

Uses

Follow the usage guidelines of Stable Diffusion v1.

Acknowledgments

• We express our gratitude to Microsoft for Startups Founders Hub for generously providing the Azure credits used during pretraining.
• We deeply appreciate the pioneering research on Latent/Stable Diffusion conducted by CompVis, Runway, and Stability AI.
• Special thanks to the contributors to LAION, Diffusers, and Gradio for their valuable support.

Citation

@article{kim2023architectural,
  title={BK-SDM: A Lightweight, Fast, and Cheap Version of Stable Diffusion},
  author={Kim, Bo-Kyeong and Song, Hyoung-Kyu and Castells, Thibault and Choi, Shinkook},
  journal={arXiv preprint arXiv:2305.15798},
  year={2023},
  url={https://arxiv.org/abs/2305.15798}
}

@article{kim2023bksdm,
  title={BK-SDM: Architecturally Compressed Stable Diffusion for Efficient Text-to-Image Generation},
  author={Kim, Bo-Kyeong and Song, Hyoung-Kyu and Castells, Thibault and Choi, Shinkook},
  journal={ICML Workshop on Efficient Systems for Foundation Models (ES-FoMo)},
  year={2023},
  url={https://openreview.net/forum?id=bOVydU0XKC}
}

This model card was written by Bo-Kyeong Kim and is based on the Stable Diffusion v1 model card.