Nano Banana

Nano Banana

Image generation and editing skill powered by Google Gemini's Nano Banana models.

Prerequisites

This skill requires a GEMINI_API_KEY in the project's .env or .env.local file:

GEMINI_API_KEY=your_api_key_here

To obtain an API key, visit: https://aistudio.google.com/apikey

Capabilities

1. Text-to-Image Generation

Generate images from text descriptions using scripts/generate_image.py:

python scripts/generate_image.py "a serene Japanese garden with cherry blossoms" \
  --aspect-ratio 16:9

Parameters:

• prompt (required): Text description of the image to generate
• --output: Output directory or file path (default: current directory)
• --filename: Custom filename (default: auto-generated with timestamp)
• --aspect-ratio: Image aspect ratio (default: 1:1)
• --model: Model to use (default: gemini-3-pro-image-preview)

2. Image Editing

Edit existing images with text prompts using scripts/edit_image.py:

python scripts/edit_image.py "remove the background and make it transparent" \
  --images photo.png

python scripts/edit_image.py "change the sky to sunset colors" \
  --images landscape.jpg \
  --output edited_landscape.png

Multiple Image Support (for consistency/reference):

python scripts/edit_image.py "create a collage combining these images" \
  --images img1.png img2.png img3.png \
  --aspect-ratio 16:9

Parameters:

• prompt (required): Text description of the edit
• --images (required): One or more input image paths
• --output: Output directory or file path (default: current directory)
• --filename: Custom filename (default: auto-generated)
• --aspect-ratio: Output aspect ratio (optional)
• --model: Model to use

Supported Parameters

Aspect Ratios

1:1 | 2:3 | 3:2 | 3:4 | 4:3 | 4:5 | 5:4 | 9:16 | 16:9 | 21:9

Models

• gemini-3-pro-image-preview (default) - Nano Banana Pro: Higher quality, advanced reasoning, supports up to 14 reference images
• gemini-2.5-flash-image - Nano Banana: Faster generation, lower cost, good for quick iterations

Usage Examples

Generate a logo:

python scripts/generate_image.py "minimalist tech company logo, blue gradient, modern" \
  --aspect-ratio 1:1 --filename logo.png

Generate social media content:

python scripts/generate_image.py "cozy coffee shop interior, warm lighting" \
  --aspect-ratio 9:16

Edit a product photo:

python scripts/edit_image.py "place this product on a wooden table with soft lighting" \
  --images product.png --aspect-ratio 4:3

Quick iteration with Flash model:

python scripts/generate_image.py "abstract art, vibrant colors" \
  --model gemini-2.5-flash-image

Resources

scripts/

• generate_image.py - Text-to-image generation script
• edit_image.py - Image editing with text prompts
• requirements.txt - Python dependencies (install with pip install -r requirements.txt)

references/

• api_reference.md - Detailed API documentation, error codes, and troubleshooting

Notes

• All generated images include SynthID watermarking (invisible, added by Gemini)
• Pro model supports up to 14 reference images for style/subject consistency
• Images are saved as JPEG by default (based on API response)
• Ensure dependencies are installed: pip install -r scripts/requirements.txt