This code is the official implementation of Hard Prompts Made Easy.

If you have any questions, feel free to email Yuxin ([email protected]).

From a given image, we first optimize a hard prompt using the PEZ algorithm and CLIP encoders. Then, we take the optimized prompts and feed them into Stable Diffusion to generate new images. The name PEZ (hard Prompts made EaZy) was inspired from the PEZ candy dispenser.

You can try out our demos on Colab or Hugging Face Space .

More Jupyter notebook examples can be found in the examples/ folder.

We recommand to run more shots to obtain more desirable prompts.

• PyTorch => 1.13.0
• transformers >= 4.23.1
• diffusers >= 0.11.1
• sentence-transformers >= 2.2.2
• ftfy >= 6.1.1
• mediapy >= 1.1.2

import open_clip
from optim_utils import * 
import argparse
from PIL import Image

# load the target image
image = Image.open(image_path)

# load args
args = argparse.Namespace()
args.__dict__.update(read_json("sample_config.json"))

# load CLIP model
device = "cuda" if torch.cuda.is_available() else "cpu"
model, _, preprocess = open_clip.create_model_and_transforms(args.clip_model, pretrained=args.clip_pretrain, device=device)

# You may modify the hyperparamters
args.prompt_len = 8 # number of tokens for the learned prompt

# optimize prompt
learned_prompt = optimize_prompt(model, preprocess, args, device, target_images=[image])
print(learned_prompt)

Note:
prompt_len: number of tokens in the optimized prompt
batch_size: number of target images/prompts been used for each iteraion
prompt_bs: number of intializations

You may check the code in prompt_lm/ folder.