Gemini Imagen

Overview

This skill enables image generation from text prompts using Google's Gemini Imagen API. It provides a reusable script that handles API authentication, request formatting, response processing, and automatic image saving with proper error handling.

When to Use This Skill

Use this skill when the user requests:

• Creating or generating images from text descriptions

• Visualizing concepts, scenes, or objects through AI-generated imagery

• Producing multiple variations of an image concept

• Creating images with specific aspect ratios or quality levels

Example requests:

• "Generate an image of a sunset over mountains"

• "Create a logo concept showing a geometric bird"

• "Make me an image of a futuristic city at night in 16:9 ratio"

• "Generate 3 variations of a robot painting artwork"

Configuration

API Key Setup

The Gemini API requires an API key for authentication. Obtain a key from Google AI Studio.

Recommended approach: Store the API key as an environment variable:

export GEMINI_API_KEY="your-api-key-here"

Alternatively, pass the key directly when invoking the script (less secure for shared environments).

Python Dependencies

The script requires these Python packages:

• requests

• HTTP client for API calls

• Pillow

• Image processing library

These are included in the project's shared virtual environment. Activate it before running:

source .venv/bin/activate # On Windows: .venv\Scripts\activate

Generating Images

Basic Usage

To generate a single image with default settings:

python scripts/generate_image.py "your prompt here" --api-key $GEMINI_API_KEY

The script will:

• Send the prompt to the Gemini Imagen API

• Receive and decode the generated image(s)

• Save images with timestamped filenames (e.g., gemini_image_20231123_142530_1.png )

• Display progress and file paths

Advanced Options

Model Selection

Choose from three quality/speed tiers:

Fast generation (default) - quickest, good quality

--model imagen-4.0-fast-generate-001

Standard generation - balanced speed and quality

--model imagen-4.0-generate-001

Ultra generation - highest quality, slower

--model imagen-4.0-ultra-generate-001

Aspect Ratios

Generate images in different dimensions:

Square (default)

--aspect-ratio 1:1

Portrait orientations

--aspect-ratio 3:4 --aspect-ratio 9:16

Landscape orientations

--aspect-ratio 4:3 --aspect-ratio 16:9

Multiple Images

Generate up to 4 variations in a single request:

--num 4

Output Directory

Specify where to save generated images:

--output ./generated_images

Complete Examples

Generate a high-quality landscape image:

python scripts/generate_image.py
"Majestic mountain range at golden hour with dramatic clouds"
--api-key $GEMINI_API_KEY
--model imagen-4.0-ultra-generate-001
--aspect-ratio 16:9
--output ./landscapes

Create multiple logo variations:

python scripts/generate_image.py
"Minimalist geometric logo for tech startup, blue and white"
--api-key $GEMINI_API_KEY
--num 4
--aspect-ratio 1:1
--output ./logo_concepts

Quick social media graphic:

python scripts/generate_image.py
"Abstract colorful pattern for social media background"
--api-key $GEMINI_API_KEY
--aspect-ratio 9:16
--output ./social_media

Workflow Integration

When a user requests image generation:

• Extract the prompt from the user's request

• Determine parameters based on context:

• Aspect ratio (square for logos, 16:9 for presentations, etc.)

• Number of variations (if user wants options)

• Quality tier (ultra for final outputs, fast for iteration)

• Invoke the script with appropriate parameters

• Show the generated images to the user and provide file paths

• Iterate if needed with refined prompts or different parameters

Best Practices

Prompt Engineering

• Be specific and descriptive: Include details about style, lighting, composition, colors

• Specify art style if desired: "digital art", "oil painting", "photorealistic", "minimalist"

• Mention important elements: Objects, subjects, background, atmosphere

• Include quality keywords: "high detail", "professional", "award-winning"

Example good prompt:

"A serene Japanese garden with cherry blossoms in full bloom, koi pond in foreground, traditional stone lantern, soft morning light, photorealistic style, high detail"

Example basic prompt (works but less controlled):

"Japanese garden"

Model Selection

• Fast model: Prototyping, iteration, quick previews, high-volume generation

• Standard model: General-purpose images, balanced quality and speed

• Ultra model: Final outputs, client presentations, high-stakes visuals

Error Handling

The script handles common errors:

• Invalid API keys → Check API key configuration

• Network timeouts → Verify internet connection, retry request

• Rate limiting → Wait and retry, consider reducing simultaneous requests

• Invalid parameters → Review model name, aspect ratio, and num_images values

Output Format

Generated images are saved as PNG files with:

• Naming convention: gemini_image_YYYYMMDD_HHMMSS_N.png

• Timestamp: Ensures unique filenames across runs

• Sequential numbering: When generating multiple images

• SynthID watermark: Automatically embedded by Imagen API

Resources

scripts/generate_image.py

The main image generation script that handles:

• API authentication and request formatting

• Base64 image decoding and PIL processing

• Automatic file saving with timestamps

• Comprehensive error handling and user feedback

• Command-line interface with all customization options

Invoke directly from the command line or integrate into larger workflows.