ComfyUI-Imagen-Gemini

ComfyUI-Imagen-Gemini

<img width="1057" height="584" alt="gemini-imagen" src="https://github.com/user-attachments/assets/881fcf7f-a631-4f6a-aab4-a0582bf2d75d" />

A custom node for ComfyUI that integrates Google's latest Imagen 4 and Imagen 3 generative models via the Gemini API.

Generate high-quality images directly within your ComfyUI workflows using Google's state-of-the-art diffusion models. Note that: The "allow_all" parameter value is not allowed in EU, UK, CH, MENA locations.

✨ Features

• Model Support: Access to the latest models including:
  • Imagen 4: Ultra, Standard, and Fast variants.
  • Imagen 3: Standard and Fast variants.
• Resolution Control: Select between 1K and 2K native generation.
• Aspect Ratios: Native support for 1:1, 3:4, 4:3, 9:16, and 16:9.
• Safety Settings: Configurable person generation filters (allow_adult, allow_all, dont_allow).
• Guidance Output: Includes a secondary text output containing official prompting guidance for Imagen 4.
• Secure Auth: Supports API keys via node widget or environment variables (GEMINI_API_KEY).

🛠️ Installation

Option 1: Git Clone (Manual)

1. Navigate to your ComfyUI custom_nodes directory.

2. Clone this repository:

   git clone [https://github.com/yourusername/ComfyUI-Imagen-Gemini.git](https://github.com/yourusername/ComfyUI-Imagen-Gemini.git)
   

3. Install dependencies (if necessary):

   pip install -r requirements.txt
   

   (Note: This node primarily uses standard libraries like requests, torch, and Pillow which are likely already installed in your ComfyUI environment.)

4. Restart ComfyUI.

🔑 API Key Configuration

You need a Google Gemini API key to use this node. You can get one here: Google AI Studio.

You can provide the key in two ways:

1. Environment Variable (Recommended): Set a GEMINI_API_KEY environment variable on your system. The node will automatically detect this, allowing you to leave the API key field in the UI blank.

2. Node Widget: Paste your API key directly into the gemini_api_key field on the node.

🎛️ Usage

1. Add Node: Right-click > ImagenGemini > Imagen Gemini.
2. Connect Prompt: Connect a string primitive or write your prompt in the widget.
3. Outputs:
   • IMAGE: The generated image tensor (connect to PreviewImage or SaveImage).
   • GUIDANCE: A string output containing prompting tips specific to Imagen models (connect to ShowText or similar).

Parameters

| Parameter | Description | | :--- | :--- | | prompt | The positive text description for image generation. | | model | Select the model version (e.g., imagen-4.0-generate-001, imagen-3.0-fast-generate-001). | | gemini_api_key | Your Google API Key. Leave empty if using env var. | | aspect_ratio | The shape of the image (1:1, 16:9, etc.). | | resolution | 1K or 2K generation. | | num_images | Batch size (1 to 4 images per request). | | person_generation | Controls generation of people: allow_adult (default), allow_all, or dont_allow. |

📋 Requirements

• ComfyUI
• Python 3.x
• requests
• torch
• Pillow
• numpy

⚠️ Notes

• Negative Prompts: Google's Imagen API implementation for these models does not currently support negative prompts or system instructions; therefore, the node only accepts a positive prompt.
• API Limits: Usage is subject to Google Gemini API quotas and pricing. Please check your Google AI Studio dashboard for details.

License

MIT