Vision Bench — LLM Image Evaluation
Compare images by scoring them with one or more vision LLM judges against structured rubric criteria.
Quick Start
# Install dependencies
pip install pyyaml openai anthropic mistralai
# Score a single image
python bench.py image.png --criteria photorealism --judge gemini-2.5-flash
# Compare two AI-generated images
python bench.py img_a.png img_b.png \
--criteria text_to_image \
--prompt "a fox in a snowy forest" \
--judge gpt-4o
# Multi-judge consensus
python bench.py img.png \
--criteria portrait \
--judges gpt-4o gemini-2.5-flash claude-opus-4-5-20251022
# OpenRouter models (any vision-capable model)
python bench.py img_a.png img_b.png \
--criteria artistic_style \
--judges "openrouter/meta-llama/llama-4-maverick" "openrouter/mistralai/pixtral-large-2411"
# List all presets
python bench.py --list-presets
# Save report to file
python bench.py img.png --criteria chart_analysis --save report.mdPresets
| Preset | Use Case |
|---|---|
text_to_image | Compare AI image generators (Midjourney, DALL-E, Flux) |
photorealism | How convincingly an image looks like a photo |
artistic_style | Style consistency, composition, color harmony |
portrait | AI-generated portrait quality and realism |
product_photo | E-commerce product image quality |
document_ocr | Document text extraction and layout understanding |
chart_analysis | Chart and data visualization comprehension |
invoice | Financial document field extraction accuracy |
ui_screenshot | App/web screenshot understanding |
scientific | Scientific/medical image accuracy |
alt_text | Accessibility image description quality |
Custom criteria: pass any .yaml file as --criteria path/to/my.yaml.
Judge Providers
| Prefix | Provider | Example |
|---|---|---|
gpt-, o1, o3, o4 | OpenAI | gpt-4o |
claude- | Anthropic | claude-sonnet-4-5-20251022 |
gemini- | Google Gemini | gemini-2.5-flash |
pixtral-, mistral-, ministral- | Mistral | pixtral-12b-2409 |
openrouter/ | OpenRouter (any model) | openrouter/meta-llama/llama-4-maverick |
API Keys
Keys are loaded from secrets.enc.yaml (SOPS + age encrypted) with fallback to environment variables.
Supported keys: OPENAI_API_KEY, ANTHROPIC_API_KEY, GEMINI_API_KEY, OPENROUTER_API_KEY
To encrypt your own keys:
sops --config .sops.yaml --encrypt --input-type yaml --output-type yaml secrets.yaml > secrets.enc.yamlOutput Formats
--output markdown (default) · --output json · --output table
Files
bench.py— CLI entry pointjudge.py— Multi-provider LLM judge logicreport.py— Report generationvault.py— SOPS secrets decryptioncriteria/— 11 YAML preset files.sops.yaml— Age key config for encryptionsecrets.enc.yaml— Encrypted API keys