Nanobanana Image Generation
Generate and edit images using Google Gemini API.
Prerequisites
| Requirement | Setup |
|---|---|
| API Key | Export GEMINI_API_KEY or add to ~/.nanobanana.env |
| Dependencies | pip install google-genai Pillow python-dotenv |
| Script | ${CLAUDE_PLUGIN_ROOT}/skills/core/nanobanana/nanobanana.py |
Basic Usage
| Task | Command |
|---|---|
| Generate image | python3 nanobanana.py --prompt "description" --output "file.png" |
| Edit image | python3 nanobanana.py --prompt "changes" --input source.png --output "edited.png" |
Aspect Ratios
| Size | Ratio | Use Case |
|---|---|---|
1024x1024 | 1:1 | Square, logos |
768x1344 | 9:16 | Portrait, stories (default) |
1344x768 | 16:9 | Landscape, wallpapers |
832x1248 | 2:3 | Portrait photos |
1248x832 | 3:2 | Landscape photos |
1536x672 | 21:9 | Ultra-wide |
Use --size WIDTHxHEIGHT to specify.
Models
| Model | Trade-off |
|---|---|
gemini-3-pro-image-preview | Higher quality (default) |
gemini-2.5-flash-image | Faster generation |
Use --model MODEL to specify.
Resolution
| Resolution | Use Case |
|---|---|
1K | Testing, drafts (default) |
2K | Good quality |
4K | Final output, print |
Use --resolution RES to specify.
Best Practices
| Practice | Why |
|---|---|
| Be descriptive | Include style, mood, colors, composition |
| Use 1:1 for logos | Clean square format |
| Use 9:16 for stories | Standard mobile format |
| Use 16:9 for wallpapers | Standard widescreen |
| Start with 1K | Test before using higher resolution |
| Use flash model for iteration | Save time during drafting |
Examples
Generate landscape:
python3 nanobanana.py --prompt "Mountain sunset with lake" --size 1344x768 --output "landscape.png"
Generate logo:
python3 nanobanana.py --prompt "Minimalist tech logo" --size 1024x1024 --output "logo.png"
Edit existing image:
python3 nanobanana.py --prompt "Add rainbow to sky" --input photo.png --output "edited.png"
High quality output:
python3 nanobanana.py --prompt "Professional portrait" --resolution 2K --output "portrait.png"
Troubleshooting
| Issue | Solution |
|---|---|
| Script fails | Check GEMINI_API_KEY is set |
| No image generated | Make prompt more specific |
| Can't read input | Verify file exists and is readable |
| Can't write output | Check directory is writable |