aigc_label now reads the TC260 label from a raw-JSON `AIGC` PNG tEXt chunk
(as Doubao/ByteDance write it, with no namespaced XMP marker) in addition to
the `<TC260:AIGC>` XMP block, via a shared _parse helper gated on a TC260 field
so a generic AIGC key cannot false-positive. New huggingface_job() reads the
hf-job-id PNG chunk; identify surfaces it as a medium-confidence hf_job signal
(parallel to the visible sparkle, never overriding a hard metadata verdict).
Both wired into has_ai_metadata/get_ai_metadata; the PNG save whitelist already
strips them on removal. Found by auditing 646 corpus originals: 28 AIGC and 3
hf-job files the library previously reported as Unknown.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Surface contradictions between independent provenance signals instead of
collapsing to a single verdict -- a strong tell of spoofed, transplanted, or
laundered metadata. Inspired by arXiv:2603.02378.
Two rules in the new _integrity_clashes helper:
- Conflicting AI-origin attributions: two or more distinct AI vendors named by
independent generator stamps (e.g. a C2PA OpenAI manifest on an image whose
EXIF says Make="Ideogram AI").
- Camera + AI: a camera-capture C2PA device (Pixel/Leica/Sony/Nikon/Truepic)
coexisting with an AI-generation marker -- a genuine capture is not AI.
High-precision by design: only hard generator stamps feed it (C2PA issuer when
the source is AI, SynthID proxy, EXIF/XMP generator, IPTC AISystemUsed, xAI,
AIGC). The fuzzy visible sparkle and the open invisible watermark are excluded
-- the latter can be a by-product of our own SDXL removal pass. Vendor
normalization (_vendor_of over _AI_VENDOR_TOKENS) keeps consistent signals from
clashing (C2PA "Google (Gemini)" + SynthID-Google agree); the C2PA vendor is
read from the issuer attribution, not the resolved platform, so a camera label
like "Google Pixel" cannot mis-normalize to an AI vendor.
Surfaced as ProvenanceReport.integrity_clashes (red in the table view, included
in --json). 19 new tests; all real single-origin fixtures (chatgpt/firefly/
doubao/grok/mj) verified to produce zero clashes (false-positive guard).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Prevents an unmapped C2PA device whose manifest incidentally contains a mapped
issuer substring (e.g. the "Adobe XMP" toolkit string in a Canon/Sony camera
capture) from being mislabeled as that AI generator ("Adobe Firefly").
_attribute_platform now names a specific AI-generator platform only when the
digital-source-type is trainedAlgorithmicMedia; otherwise it degrades to the
neutral "C2PA signer: X" label. Real Firefly/OpenAI/Google output carries the
AI source-type and is unaffected (verified: chatgpt-1.png->OpenAI,
firefly-1.png->Adobe Firefly still attribute). Closes the only real downside of
leaving Canon/Samsung/Bria device signers unmapped: detection and removal were
already unaffected; now the platform label degrades gracefully too.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds Sony to _DEVICE_C2PA_PLATFORM, matching Sony's own `sony.sig` / `sony.cert`
C2PA assertion namespace (NOT bare "Sony", which is a common EXIF Make). Verified
against a real Sony-signed file (Sony PXW-Z300, signer "Sony Corporation") found
in the Security4Media/c2pa-video-player repo. The sample is video (MP4) -- our
ISOBMFF C2PA path detects it; Sony Alpha stills likely share the namespace.
Verified device set is now Leica, Nikon, Google Pixel, Sony, Truepic. Canon /
Samsung / Bria still have no public direct-download C2PA sample to verify.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Replaces the claim-generator-string match with a distinctive device-token scan
of the manifest bytes (_device_platform / _DEVICE_C2PA_PLATFORM), which is more
robust: it catches devices where the generator name lives under a non-standard
CBOR key (Pixel uses `claim_generator_info`, so it has no `claim_generator`).
- Adds Google Pixel, verified against a real Pixel 10 Pro C2PA file (attached to
c2pa-rs issue #1609/#1554): cert CN "Pixel Camera", digitalSourceType
`computationalCapture` -> capture authenticity, not AI (is_ai stays None).
- Token distinctiveness is load-bearing: bare "Truepic" matched the OpenAI
chatgpt-1.png fixture (Truepic is a trust-chain signing authority), so the
token is the specific "Truepic_Lens"; "Pixel Camera" (cert CN) not "Pixel".
- Verified Leica/Nikon/Truepic/Pixel attribute correctly and OpenAI/Adobe/MJ
do not regress. Sony/Canon/Samsung/Bria stay unmapped: no public direct-
download C2PA sample exists to verify their in-manifest string.
- Regression tests: device token beats incidental issuer mentions (Leica,
Pixel-vs-Google).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Verified on real signed files that the issuer byte-scan mis-attributes
multi-entity manifests: Leica read as "Truepic" (timestamp authority in the
chain), Nikon as "Adobe Firefly" (XMP-toolkit "Adobe" + the sample's
"Adobe_MAX" name), Truepic as "Google". Platform attribution now prefers the
claim generator (what produced the asset) and falls back to the issuer scan.
- New _CLAIM_GENERATOR_PLATFORM map + _platform_from_generator; claim generator
read for non-PNG via the now-public c2pa.cbor_text_after.
- Device tokens listed only where verified against a real C2PA file (Leica
lc_c2pa, Nikon, Truepic Lens); Pixel/Samsung/Sony/Canon/Bria deferred until a
real sample confirms the in-manifest string. Camera C2PA marks capture
authenticity, so these never set is_ai.
- cbor_text_after made public (was _cbor_text_after); call sites + tests updated.
- Regression test: claim_generator beats incidental Adobe/Google/Truepic tokens.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Broadens metadata provenance coverage at the detection and container-strip level.
Detection:
- C2PA soft-binding `alg` -> forensic-watermark vendor (Adobe TrustMark,
Digimarc, Imatag, Steg.AI, Microsoft, ...) via C2PA_SOFT_BINDINGS +
soft_binding_vendors_in(); names the watermark vendor even when the watermark
itself can't be decoded.
- IPTC Photo Metadata 2025.1 AI-disclosure XMP fields (AISystemUsed etc.) via
iptc_ai_system() + IPTC_AI_FIELD_MARKERS.
- Adobe TrustMark open keyless decoder (trustmark_detector.py, optional extra
`trustmark`) -- the watermark behind Adobe Durable Content Credentials.
Detects provenance, not AI origin, so it does not assert is_ai.
Removal / containers:
- isobmff.strip_c2pa_boxes now also drops a top-level XMP uuid box that carries
an AI label (matched by AI-marker content, byte-order-robust; plain XMP kept).
- remove_ai_metadata routes MP4/MOV/M4V/M4A (and any ftyp-sniffed ISOBMFF)
through the box stripper; raises a clear error for non-ISOBMFF audio/video
(WebM/MP3/WAV) instead of crashing in the image path.
Tests: soft-binding scan, IPTC element/attribute/presence, MP4 + M4A detect/
strip, ISOBMFF XMP surgical strip, content-sniff, unsupported-container guard,
TrustMark absent-safety + identify integration. ruff clean; pyright clean on
all new modules.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
xAI Grok (Aurora) images carry no C2PA/SynthID/IPTC -- their only provenance
signal is an EXIF pair: ImageDescription "Signature: <base64>" + a UUID Artist.
Verified stable across 3 genuine generations (a real download previously read
as unknown / "no AI metadata").
- metadata.xai_signature(): matches the Signature blob + UUID Artist pair;
wired into has_ai_metadata, get_ai_metadata, and identify (platform
"xAI (Grok / Aurora)").
- data/samples/grok-1.jpg: real Grok fixture (neutral content; the Artist UUID
is the public image id, not PII).
- Tests: synthetic-fixture unit tests, real-sample assertion, identify
integration (322 passing).
Docs (research refresh, May 2026):
- C2PA 2.4 Durable Content Credentials (soft-binding re-discovery after the
embedded manifest is stripped).
- New AI-labeling laws, primary-source verified: EU AI Act Art 50 (2026-08-02),
South Korea AI Framework Act Art 31(3), California AB 853.
- Hedge removal claims: defeating the SynthID verifier is not forensic
invisibility (arXiv:2605.09203); cite SynthID-Image (arXiv:2510.09263).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Corpus images were gitignored (local-only). The negatives were reviewed and
cleared for publishing, so the labeled set is now committed (regular git, 65 MB
across 25 files) -- making the removal regression set reproducible and CI-able.
Corpus:
- Track data/synthid_corpus/images/ (pos 9, neg 15, cleaned 1); keep only the
synthetic refs/ calibration fills gitignored.
- Reconcile manifest.csv to the on-disk files: 117 -> 25 rows (92 dangling rows
for removed images pruned; dedup left one cleaned output, f6dd47a5).
- Rewrite the corpus README layout/policy (images committed; review every image
for private content before adding -- public repo, permanent history).
Test fixtures:
- Remove data/samples/not-ai-1/2/3 (personal iPhone photos, incl. GPS EXIF).
- Add the clean_photo conftest fixture serving a verified-negative image from
the corpus neg/ set; repoint the three "non-AI / clean photo" tests onto it
(skips if the corpus is absent).
Metadata-source coverage (close the last sub-variant gaps):
- c2pa digitalSourceType: algorithmicMedia (procedural, not flagged AI) and
compositeWithTrainedAlgorithmicMedia (AI + SynthID proxy).
- exif_generator: EXIF Artist and ImageDescription fields (Software/Make/XMP
CreatorTool were already covered).
All 8 metadata-source kinds are now tested at both the unit and identify()
level. 313 tests pass. CLAUDE.md updated (corpus tracked, clean_photo fixture).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Closes the documented gap where EXIF/XMP fields inside AVIF/HEIF/JXL went
unparsed. metadata.exif_generator extracts the EXIF Software/Artist tag
(via PIL+piexif, which opens AVIF natively) and the XMP CreatorTool (via a
container-agnostic raw-byte scan that also covers HEIF/JXL that PIL can't
open), and matches against AI_GENERATOR_TOKENS so only generator names
(Firefly, DALL-E, Midjourney, ComfyUI, ...) fire -- a plain 'Adobe
Photoshop' or 'GIMP' tag is not flagged.
identify() surfaces it as a high-confidence signal and uses it for
platform attribution when no C2PA names a platform, so an AVIF/HEIF whose
only AI signal is an EXIF/XMP generator tag is now caught.
Validated with synthesized fixtures (the 'no positive fixtures' blocker
was self-imposed): real AVIF and JPEG written with EXIF Software via PIL,
plus an XMP CreatorTool raw-scan fixture. Zero false positives across the
109-image corpus (real iPhone photos carry no AI generator token).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Collected live C2PA positives from Bing Image Creator and Stability Brand
Studio (DreamStudio successor) and learned two things our scan got wrong:
- Bing now runs Microsoft's own MAI-Image model, not DALL-E, and signs
C2PA as 'Microsoft'. The scan caught it, but the platform label claimed
'Microsoft Designer (DALL-E / OpenAI backend)'. Relabeled model-neutral:
'Microsoft (Bing Image Creator / Designer)'.
- Stability signs C2PA as 'Stability AI' (cert 'Stability AI Ltd'), which
was not in C2PA_ISSUERS, so it read as 'unknown signer'. Added the issuer
and a platform mapping. Stability uses no SynthID and (on its current
Stable Image model) no imwatermark watermark -- verified, both negative.
Both ingested as SynthID-negative corpus fixtures (they are AI but not
SynthID) for issuer-coverage. Canva skipped: its downloads are re-encoded
design exports that strip C2PA, so a Canva sample would be inconclusive.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Research found one locally-fillable detection gap: Stable Diffusion, SDXL,
and FLUX all embed an open DWT-DCT watermark via the invisible-watermark
(imwatermark) library -- a PUBLIC decoder, no secret key, unlike SynthID.
New invisible_watermark.py decodes the known fixed patterns (verified
against upstream source: diffusers SDXL WATERMARK_MESSAGE, FLUX.2
src/flux2/watermark.py, and the 'StableDiffusionV1' default string) and
identify() reports the scheme as a high-confidence signal.
Verified locally end-to-end: embedding SDXL's exact 48-bit message and
decoding it back recovers 48/48 bits; a clean image and our own fal-SDXL
outputs decode to ~21/48 (no match). Caveat baked into the report: the
watermark is fragile -- gone after JPEG q90 -- so it confirms origin only
on pristine files; absence is never proof.
imwatermark is an optional dep (extra 'detect'; pulls non-headless opencv),
so the import is guarded and the signal is skipped when absent. CLI
--no-visible now means metadata-only (skips both pixel-domain detectors).
Also records the broader watermarking landscape in CLAUDE.md: which
services are locally detectable (SD/SDXL/FLUX), C2PA-covered (Bing/Canva/
Getty/Shutterstock unsampled), or proprietary-only like SynthID (Amazon
Titan/Nova, Kakao). Midjourney embeds neither C2PA nor an invisible mark.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds 20 tests around the new provenance path:
- identify(): local SD/ComfyUI params -> local-pipeline attribution;
visible-sparkle gating at the 0.5 threshold (mocked detector: above,
below, unavailable, opt-out); metadata verdict not downgraded by a
sparkle hit; OpenAI/SynthID caveats + dedup; ProvenanceReport is
JSON-serializable (the CLI --json path); and the honest edge where a
C2PA manifest without an AI source marker stays 'unknown'.
- CLI 'identify': help, clean PNG, AI PNG platform, valid --json,
missing file.
- gemini_engine.detect_sparkle_confidence: float in range for a real
image, None for an unreadable file.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
New 'identify' command and identify.py module: upload an image, get one
ProvenanceReport answering where it was made and what watermarks it
carries. Aggregates every locally-readable signal:
- C2PA Content Credentials -> generating platform (issuer + generator).
- IPTC digitalSourceType 'Made with AI' (Meta and others).
- Embedded SD/ComfyUI generation parameters (local pipelines).
- SynthID metadata proxy (Google / OpenAI C2PA companion).
- Visible Gemini sparkle (cv2 fallback for the stripped-metadata case),
promoted only at confidence >= 0.5 (corpus-tuned: Gemini sparkles
score >= 0.56, non-sparkle <= 0.49).
is_ai_generated is True or None, never asserted False -- stripped
metadata leaves no local proof of a clean origin, so absence of signals
is reported as 'unknown' with an explicit caveat. The SynthID *pixel*
watermark remains locally undecodable; the report says so.
Non-PNG containers (JPEG/WebP/AVIF/HEIF/JXL) get the same issuer +
generator attribution via a binary scan (the caBX parser is PNG-only).
The cv2 dependency is isolated in gemini_engine.detect_sparkle_confidence
so identify.py stays type-clean. CLI supports --json and --no-visible.
Validated against the 109-image corpus: 14/14 positives flagged AI,
93/94 negatives clean (the one 'neg' flagged is a Meta image that
genuinely carries the IPTC tag -- correct), zero true errors.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Victor Kuznetsov