- metadata --check now shows claim_generator, c2pa_spec, digital_source_type, c2pa_actions, signer instead of empty table for C2PA-only files - reuses existing extract_c2pa_chunk() from noai/c2pa.py — no more duplicate PNG chunk parsing or full-file reads - adds data/samples/openai-images-2/amur-leopard.png: real gpt-image-2 output with C2PA manifest signed by OpenAI OpCo LLC / Trufo CA (spec 2.2.0) - removes stale data/samples/nano-banana-1/2.png (no longer referenced) - updates README: new Images 2.0 row in supported models table - documents known text-degradation limitation in CLAUDE.md Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
OpenAI ChatGPT Images 2.0 sample
Reference image generated by OpenAI's ChatGPT Images 2.0 (gpt-image-2, launched 2026-04-21). Kept in the repo so the C2PA manifest parser and invisible-watermark pipeline can be re-verified against a real production output.
amur-leopard.png
- Resolution: 1055 x 1491, PNG, 3.0 MB
- Downloaded: 2026-04-22
- Content: AI-generated infographic about the Amur leopard (Panthera pardus orientalis), chosen to exercise the model's new accurate-text-rendering feature
Embedded C2PA manifest (caBX chunk, 23607 bytes)
Parsed by remove-ai-watermarks metadata --check:
| Field | Value |
|---|---|
claim_generator |
GPT-4o |
c2pa_spec |
2.2.0 |
digital_source_type |
http://cv.iptc.org/newscodes/digitalsourcetype/trainedAlgorithmicMedia |
c2pa_actions |
created, converted |
| Signer | OpenAI OpCo, LLC / OpenAI Media Service API |
| Claim signing CA | Trufo C2PA Claim Signing CA (2025) -> Trufo C2PA Root CA (ECC P384) |
| Timestamp authority | OpenAI TSA Issuing CA -> OpenAI TSA Root CA |
The trainedAlgorithmicMedia tag is what triggers "Made with AI" labels on Instagram, Facebook, and X.
Invisible pixel-level watermark
OpenAI's system card for Images 2.0 states the model embeds an "imperceptible, robust, and content-specific" pixel-level watermark alongside C2PA. No public detector exists, so bypass cannot be verified empirically for this sample.
Reproducing the removal
# C2PA strip only
remove-ai-watermarks metadata amur-leopard.png --remove -o amur-leopard.clean.png
# Full pipeline (visible + diffusion regeneration + metadata)
remove-ai-watermarks all amur-leopard.png -o amur-leopard.all.png --device mps
Note: the diffusion step downscales to 768 px, which degrades fine text on text-heavy infographics like this one. Tracked as a known limitation; see project TODO.