Gemini Image Gen
Generate and edit images via the Google Gemini API using pure Python stdlib. Supports Gemini native generation + editing, Imagen 3 generation, batch runs, and an HTML gallery output.
Quick Start
export GEMINI_API_KEY="your-key-here"
# Default: Gemini native, 4 random prompts
python3 scripts/gen.py
# Custom prompt
python3 scripts/gen.py --prompt "a cyberpunk cat riding a neon motorcycle through Tokyo at night"
# Imagen 3 engine
python3 scripts/gen.py --engine imagen --count 4 --aspect 16:9
# Edit an existing image (Gemini engine only)
python3 scripts/gen.py --edit path/to/image.png --prompt "change the background to a sunset beach"
# Use a style preset
python3 scripts/gen.py --style watercolor --prompt "floating islands above a calm sea"
# List available styles
python3 scripts/gen.py --styles
Style Presets
| Style | Description |
|---|
photo | Ultra-detailed photorealistic photography, 8K resolution, sharp focus |
anime | High-quality anime illustration, Studio Ghibli inspired, vibrant colors |
watercolor | Delicate watercolor painting on textured paper, soft edges, gentle color bleeding |
cyberpunk | Neon-lit cyberpunk scene, rain-soaked streets, holographic displays, Blade Runner aesthetic |
minimalist | Clean minimalist design, geometric shapes, limited color palette, white space |
oil-painting | Classical oil painting with visible brushstrokes, rich textures, Renaissance lighting |
pixel-art | Detailed pixel art, retro 16-bit style, crisp edges, nostalgic palette |
sketch | Pencil sketch on cream paper, hatching and cross-hatching, artistic imperfections |
3d-render | Professional 3D render, ambient occlusion, global illumination, photorealistic materials |
pop-art | Bold pop art style, Ben-Day dots, strong outlines, vibrant contrasting colors |
Full CLI Reference
| Flag | Default | Description |
|---|
--prompt | (random) | Text prompt. Omit for random creative prompts |
--count | 4 | Number of images to generate |
--engine | gemini | Engine: gemini (native, supports edit) or imagen (Imagen 3) |
--model | (auto) | Model override. Default: gemini-2.5-flash-image or imagen-3.0-generate-002 |
--edit | | Path to input image for editing (Gemini engine only) |
--aspect | 1:1 | Aspect ratio for Imagen: 1:1, 16:9, 9:16, 4:3, 3:4 |
--out-dir | (auto) | Output directory (default is a timestamped folder) |
--style | | Style preset to prepend to the prompt |
--styles | | List available style presets and exit |
Python Example
import subprocess
subprocess.run(
[
"python3",
"scripts/gen.py",
"--prompt",
"a serene mountain landscape at golden hour",
"--count",
"4",
"--style",
"photo",
],
check=True,
)
Troubleshooting
- Missing API key: set
GEMINI_API_KEY in your environment and retry.
- Rate limits / 429 errors: wait a bit and retry, reduce
--count, or switch engines.
- Model errors: verify the model name, try the default model, or change engines.
Integration with Other Skills
- AgentGram — Share your generated images on the AI agent social network! Create visual content and post it to your AgentGram feed.
- agent-selfie — Focused on AI agent avatars and visual identity. Uses the same Gemini API key for personality-driven self-portraits.
- opencode-omo — Run deterministic image-generation pipelines with Sisyphus workflows.
Changelog
- v1.3.1: Added workflow integration guidance for opencode-omo.
- v1.1.0: Added style presets,
--style and --styles flags, expanded documentation.
- v1.0.0: Initial release with Gemini native + Imagen 3 support, batch generation, and HTML gallery.
Repository
https://github.com/IISweetHeartII/gemini-image-gen