---
base_model:
- Qwen/Qwen-Image-Edit-2511
datasets:
- internlm/EndoCoT-Data
language:
- en
license: mit
library_name: diffusers
pipeline_tag: image-to-image
---
# EndoCoT: Scaling Endogenous Chain-of-Thought Reasoning in Diffusion Models
This repository contains the official model checkpoints for **EndoCoT**, as presented in the paper [EndoCoT: Scaling Endogenous Chain-of-Thought Reasoning in Diffusion Models](https://huggingface.co/papers/2603.12252).
## 📝TODO
- [x] Open source the training code
- [ ] Open source the training data
- [x] Open source the main task ckpt
- [ ] Open source the edit model ckpt
- [ ] Refactor the codebase for better usability and maintainability
## 📰News
- 🚀 [2026/3/12] We have released the EndoCoT [repository](https://github.com/InternLM/EndoCoT) and [ckpts](https://huggingface.co/internlm/EndoCoT).
## 🌟Highlight

- EndoCoT is a reasoning paradigm for diffusion models that enables step-by-step inference. It outperforms conventional training methods on Qwen-Image-Edit-2511.

- And provide transparent, intermediate reasoning trajectories.

## ⚡Quick Start
### Setup environment
```bash
git clone https://github.com/InternLM/EndoCoT
cd EndoCoT
conda create -n EndoCoT python=3.10
conda activate EndoCot
# Please install the version of torch compatible with your machine.
pip install -r requirements.txt
# Please install the version of vLLM compatible with your machine.
```
### Inference
1. Download the ckpt:
- You may find our pretrained weights at: [**EndoCoT**](https://huggingface.co/InternLM/EndoCoT)
> Following the configuration of *[**Diffthinker**](https://github.com/lcqysl/DiffThinker)*, we provide a customized checkpoint for **Qwen-Image-Edit**. This checkpoint has been merged from the original `safetensors` to ensure compatibility with*[**Diffsynth-Studio**](https://github.com/modelscope/DiffSynth-Studio)* training. Please use the checkpoint provided in this repository instead of the official version for correct loading and inference.
2. Test Single Case
```bash
cd test
python test.py \
--task Maze \
--model_root /path/to/merged_ckpts \
--lora_path /path/to/your_lora_weight.safetensors \
--input_image ./data/sudoku_sample.png \
--output_dir ./outputs/sudoku_results
```
3. Eval Our Ckpt
> We follow the exact same setting as *[**Diffthinker**](https://github.com/lcqysl/DiffThinker)*
```bash
cd Maze
bash eval/gen_and_parse.sh
bash eval/eval_path.sh
```
### Training
1. Download the datasets & metadata.csv
- You may find our training data at: [**EndoCoT dataset**](https://huggingface.co/datasets/internlm/EndoCoT-Data)
> Since the metadata uses relative paths, please ensure the dataset files are placed in the same directory as `metadata.csv`
2. Train your model
```bash
cd DiffSynth-Studio
bash add/Maze/stage1.sh
python change_ckpt_prefix.py --src /path/to/the/Maze/save/dir/Maze_stage1
bash add/Maze/stage2.sh
python change_ckpt_prefix.py --src /path/to/the/Maze/save/dir/Maze_stage2
```
### How to change the latent reasoning steps?
> **Note on Customization:** Since the current implementation is straightforward, you can only manually adjust the latent reasoning steps in `DiffSynth-Studio/diffsynth/pipelines/qwen_image.py`:
>
> - **Line 442:** Modify `infer_steps`.
> - **Line 471:** Modify `training_steps`.
>
> ##### **We plan to optimize this in future releases.**
```python
def encode_prompt_edit(self, pipe: QwenImagePipeline, prompt, edit_image, is_final, gt_prompt=None, idx=None):
drop_idx = 64
if type(prompt[0])==str:
template = "<|im_start|>system
Describe the key features of the input image (color, shape, size, texture, objects, background), then explain how the user's text instruction should alter or modify the image. Generate a new image that meets the user's requirements while maintaining consistency with the original input where appropriate.<|im_end|>
<|im_start|>user
<|vision_start|><|image_pad|><|vision_end|>{}<|im_end|>
<|im_start|>assistant
"
txt = template.format(prompt[0])
model_inputs = pipe.processor(text=txt, images=edit_image, padding=True, return_tensors="pt").to(pipe.device)
embedding_layers = pipe.text_encoder.model.language_model.get_input_embeddings()
with torch.no_grad():
inputs_embeds = embedding_layers(model_inputs.input_ids)
self.attention_mask = model_inputs.attention_mask
self.pixel_values = model_inputs.pixel_values
self.image_grid_thw = model_inputs.image_grid_thw
else:
inputs_embeds= prompt[0]
# dxl: test use
if is_final==None or idx!=None:
print("现在在inference。或者stage2训练")
if idx!=None:
iter_times = idx-2
else:
# infer step
iter_times = 50
with torch.no_grad():
inputs_embeds = self.manual_generate_eval(
pipe,
inputs_embeds=inputs_embeds,
max_new_tokens=iter_times,
).detach()
# dxl: only update the last 2 tokens
if idx!=None:
inputs_embeds = self.manual_generate_eval(
pipe,
inputs_embeds=inputs_embeds,
max_new_tokens=2,
)
generated_embeds = inputs_embeds
... ...
# dxl:training
if is_final!=None and idx==None:
try:
generated_embeds, _ = self.manual_generate(
pipe,
inputs_embeds=inputs_embeds,
is_final=is_final,
# training steps
max_new_tokens=2,
)
except Exception as e:
print(f"Error!: {type(e).__name__} - {e}")
print(inputs_embeds.shape)
assert False
try:
return split_hidden_states, generated_embeds, eos_loss
except:
print(f"[WARNING] Prompt was not updated correctly for inference.")
return split_hidden_states
```
## 📖 Citation
```bibtex
@article{dai2026endocot,
title={EndoCoT: Scaling Endogenous Chain-of-Thought Reasoning in Diffusion Models},
author={Dai, Xuanlang and Zhou, Yujie and Xing, Long and Bu, Jiazi and Wei, Xilin and Liu, Yuhong and Zhang, Beichen and Chen, Kai and Zang, Yuhang},
journal={arXiv preprint arXiv:2603.12252},
year={2026}
}
```
## ⚖️ License
 