image-generation

name	image-generation
description	Generate images using nano banana.

Image Generation Skill

Generate images using Nano Banana (Google Gemini Image API). Supports text-to-image and image-to-image generation with configurable options.

Setup

Dependencies

pip install google-genai Pillow

Environment Variable

Set your API key:

export GEMINI_API_KEY="your_api_key_here"

Usage

Basic Text-to-Image

python scripts/generate.py --prompt "A futuristic city at sunset with neon lights" --output city.png

With Aspect Ratio

python scripts/generate.py \
  --prompt "Mountain landscape with a lake" \
  --output landscape.png \
  --aspect-ratio 16:9

Image-to-Image Mode

Use a reference image to guide generation:

python scripts/generate.py \
  --prompt "Make it look like a watercolor painting" \
  --input-image original.png \
  --output watercolor.png

Generate Multiple Images

python scripts/generate.py \
  --prompt "Abstract colorful art" \
  --output art.png \
  --num-images 3

Arguments

Argument	Short	Required	Default	Description
--prompt	-p	Yes	—	Text prompt describing the desired image
--output	-o	No	output.png	Output path for the generated image
--model	-m	No	gemini-2.0-flash-preview-image-generation	Model to use for generation
--input-image	-i	No	—	Reference image for image-to-image mode
--aspect-ratio	-a	No	—	Aspect ratio: 1:1, 16:9, 9:16, 4:3, 3:4
--num-images	-n	No	1	Number of images to generate

Available Models

• gemini-2.0-flash-preview-image-generation - Fast, optimized for speed and lower latency
• imagen-3.0-generate-002 - High quality image generation

Programmatic Usage

Import the function directly in Python:

from scripts.generate import generate_image

paths = generate_image(
    prompt="A serene mountain lake under moonlight",
    output_path="./outputs/lake.png",
    aspect_ratio="16:9",
    num_images=2,
)

Tips

• Detailed prompts work better: Instead of "a cat", try "a fluffy orange tabby cat sitting on a windowsill, soft morning light, photorealistic"
• Specify style: Include style keywords like "digital art", "oil painting", "photorealistic", "anime style"
• Use aspect ratios: Match the aspect ratio to your intended use (16:9 for landscapes, 9:16 for portraits/mobile)
• Image-to-image: Great for style transfer, variations, or guided modifications of existing images