AI System for Alt-Text Generation for Images
Alt-texts are SEO and accessibility simultaneously. Manual writing for large media libraries is unrealistic: thousands of images remain without descriptions. Automation via vision-language models solves this task with quality approaching editorial standard.
Technical Stack
Vision-Language Models:
- GPT-4V / GPT-4o — best description quality, page context support
- LLaVA-1.6 / InternVL2 — self-hosted variant without data transfer
- BLIP-2 — light variant for high-frequency generation
Integration:
- REST API for CMS (WordPress, Contentful, Strapi)
- Bulk processing via S3/GCS bucket
- Real-time hook on image upload
What Gets Generated
System considers page context (title, category, surrounding text) and generates: brief alt (up to 125 characters for screen readers), extended description for SEO, structured data (objects, actions, colors).
Deployment: 1–2 weeks
Integration with existing CMS or DAM. Prompt configuration to brand standards (description style, what to include/exclude). Bulk processing of existing library.
| Parameter | Value |
|---|---|
| Processing Speed | 100–500 images/min (batch) |
| Description Accuracy | ~94% (vs. human benchmark) |
| Language Support | 50+ |
| WCAG 2.1 AA Compliance | Yes |