adamopoa/pdf-accessibility repository overview

⁠pdf-accessibility — Programmatic PDF Accessibility Remediation

Drop in any untagged PDF → get back a WCAG 2.2 / PDF/UA-1 (ISO 14289-1) / WTPDF 1.0 Accessibility compliant document. 100% local. No Adobe subscription, no cloud round-trip, no data leaves your network.

⁠Quick start

docker run -d --name pdf-a11y -p 8000:8000 \
  -e VLM_BASE_URL="http://your-vlm-host:1234/v1" \
  -e VLM_MODEL="qwen/qwen3-vl-30b" \
  -v pdf-a11y-jobs:/data/jobs \
  adamopoa/pdf-accessibility:latest

Open http://<host>:8000 — that's the upload form pictured above.

⁠What's inside the image

• Python 3.11 + the pdf_a11y remediation pipeline
• default-jre-headless for the opendataloader-pdf structure tagger (local, Apache 2.0)
• veraPDF 1.30.1 for PDF/UA-1 and WTPDF 1.0 Accessibility validation
• FastAPI web app on port 8000 — browser UI and a headless OpenAPI at /docs
• The bundled example PDF at /app/examples/ so you can try it without supplying one

The only external dependency at runtime is a vision-model endpoint (any OpenAI-compatible server — LM Studio, vLLM, llama.cpp server, Ollama, …) for image alt text. Cloud Anthropic / OpenAI are supported via the config file.

⁠The pipeline

opendataloader tagging → artifact-wrap pass → shared-Form-XObject cleanup → reading-order analysis → table header detection → VLM-driven alt text → form-field labels → contrast remediation → language-of-parts detection → WTPDF profile fixes → veraPDF validation.

On the bundled European Commission A short guide to the EU (36 pages, ~10 MB): veraPDF PDF/UA-1 0/106 failures, veraPDF WTPDF 1.0 Accessibility 0/1723 failures.

⁠Live progress in the UI

⁠Compliance pills + downloads

⁠Human-in-the-loop review

Optional Review image descriptions screen lets a non-technical reviewer audit every AI-generated alt text, edit it, or mark images decorative — then re-run with the corrections merged in.

⁠Headless API for CI/CD

Interactive OpenAPI docs are at /docs:

Endpoints include POST /api/jobs, GET /api/jobs/{id}, GET /api/jobs/{id}/download/{kind}, POST /api/jobs/{id}/refine, and POST /api/test-vlm for VLM-endpoint health checks.

⁠Tags

⁠Environment variables

⁠Volume

Mount /data/jobs to a named volume (-v pdf-a11y-jobs:/data/jobs) so uploads and results survive container restarts.

⁠Healthcheck

Built-in: GET /health → {"status":"ok","verapdf":true}. Docker reports the container as healthy once veraPDF is reachable on the wired-in path.

⁠Source, sponsor, contact

• Source code & full README: https://github.com/adamopoulosa1980/pdf_accessibility⁠
• Sponsor the open-source work: ☕ Buy Me a Coffee⁠
• Commercial services — on-prem deployment, local VLM provisioning & tuning, bulk remediation projects, prioritized feature work: [email protected]⁠

© 2026 ASSERT I.K.E. — Maintained by Alex Adamopoulos.