ComfyUI-PIH

ComfyUI custom nodes for Semi-supervised Parametric Real-world Image Harmonization (PIH).

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Credits

This node wraps the original PIH research code by:

Ke Wang, Michaël Gharbi, He Zhang, Zhihao Xia, Eli Shechtman
Adobe Research — CVPR 2023

Project Page | Paper | Original Repo

Please contact Ke ([email protected]) or Michaël ([email protected]) with questions about the underlying model.

If you use this in your research, please cite the original paper:

@article{wang2023semi,
  title={Semi-supervised Parametric Real-world Image Harmonization},
  author={Wang, Ke and Gharbi, Micha{\"e}l and Zhang, He and Xia, Zhihao and Shechtman, Eli},
  booktitle = {Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR)},
  year      = {2023}
}

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PIH blends a composited foreground into a background by learning complex local appearance harmonization — matching color, tone, and shading — from unpaired real composites.

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Examples

Same dog cutout, two very different backgrounds — PIH adapts the lighting, color, and tone to each scene:

| Tropical beach | Dusk alley | |----------------|------------| | | |

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Nodes

| Node | Description | |------|-------------| | PIH Model Loader | Loads the PIH checkpoint (auto-downloads on first use) | | PIH Harmonize | Blends a foreground into a background with harmonization |

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Installation

Via ComfyUI-Manager (recommended)

Search for ComfyUI PIH in the Custom Nodes section and click Install.

Manual

cd ComfyUI/custom_nodes
git clone https://github.com/chrismyau/ComfyUI-PIH
cd ComfyUI-PIH
pip install -r requirements.txt

Model Checkpoint

The checkpoint (~93M parameters, trained on Artist Retouched Dataset) downloads automatically the first time you run the PIH Model Loader node.

It is saved to ComfyUI/models/PIH/ckpt_g39.pth.

To download manually: Google Drive link — place the file at ComfyUI/models/PIH/ckpt_g39.pth.

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Usage

1. Add PIH Model Loader → connect its PIH Processor output to PIH Harmonize
2. Connect your Background Image and Foreground Image (RGB or RGBA) to PIH Harmonize
3. Optionally connect a mask to control which region is harmonized
4. Adjust Strength (0–1) to blend between the original composite and the harmonized result

⚠️ Mask polarity

This node uses the compositing convention: mask = 1 where the foreground subject is, 0 elsewhere.

ComfyUI's built-in LoadImage node outputs an inverted mask (1 - alpha) because it's designed for inpainting workflows. If you're feeding the MASK output of LoadImage from a PNG with a transparent background, insert an InvertMask node between LoadImage and PIH Harmonize, or you'll harmonize the background instead of the subject.

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License

Apache 2.0 — see LICENSE. Original PIH model code © 2023 Adobe.