Corpus-mined vendor gaps (42k-file metadata scan, 2026-07-23):
- Bria AI signs C2PA as "Bria Artificial Intelligence" with source type
empty (no trainedAlgorithmicMedia), so identify was completely blind;
registered with asserts_ai like Dreamina.
- fal.ai ("fal - Features & Labels Inc.", fal-ai/<model> generators)
was detected via the source type but never attributed; registered,
also asserts_ai as a pure generative platform.
- Apple Photos Clean Up (Apple Intelligence object removal) was detected
as a generic made-with-AI tag; now attributed as an AI edit via the
photoshop:Credit marker, and the credit value joins
AI_GENERATOR_TOKENS so removal strips it in parity.
Each new test was verified red without its fix.
remove_ai_metadata chose its save format (and the lossless-JPEG fast path)
from the OUTPUT file extension. On the ~2% of real uploads whose extension
lies about their content (a PNG served as .jpg is the common case, ~0.9% of
the corpus), the default flow -- which inherits the source's own extension --
re-encoded a lossless PNG/WebP into a real JPEG, silently degrading the pixels
and breaking the "work with originals" invariant.
Sniff the actual container from magic bytes (_sniff_image_format, reusing the
12-byte head already read for the ISOBMFF check) and route on content: a
misnamed lossless source (source-extension format != content) is preserved in
its true format, while a correctly-named source still honors a deliberate
output-extension conversion (source.png -> output.jpg). The JPEG-lossless gate
is likewise content-gated.
Found by a new metadata-removal parity audit over the local corpus
(scripts/metadata_removal_audit.py): 18170/18173 carriers strip cleanly, and
this fix takes the 208 pixel-integrity failures (all misnamed PNGs) to 0.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Full-corpus strip audit surfaced 24 china_aigc survivors on real uploads:
- 19 JPEG carried the bare AIGC{...} blob in APP11 (0xEB). That marker's branch
in _jpeg_app_carries_ai only tested for a C2PA/JUMBF manifest and RETURNED, so
a bare AIGC there slipped past the generic AIGC check. The specific
C2PA(APP11)/XMP(APP1)/IPTC(APP13) checks now fall through to the generic
_is_aigc_exif_value drop, which runs for every APP marker they did not claim.
- PNG carried the {"AIGC":{...}} block in a STANDARD text chunk (Description).
_is_ai_key keeps that key, so removal now also drops a text value carrying an
AIGC block (_is_aigc_exif_value broadened to accept str; wired into the PNG
re-save value filter), in parity with aigc_label's detection.
Verified on the corpus: decodable china_aigc survivors 27 -> 0; the 3 remaining
are truncated files the strip fail-safe (v0.15.1) copies through by design.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
PIL raises OSError decoding a truncated file, which crashed remove_ai_metadata
(the PNG/WebP PIL re-save path) -- a direct library caller like a web worker
500s on a partial upload. ~0.2% of the real upload corpus is truncated. The
strip now probes decodability first and, on failure, copies the input through
unchanged and returns rather than raising (we cannot strip what we cannot parse),
mirroring strip_c2pa_boxes' fail-safe. identify already handled these.
The CLI `metadata --remove` on an unreadable file therefore now exits 0 with the
input passed through, not a clean error (exit 1) -- `visible`, which must decode
to remove a mark, still exits 1. Test updated to the per-command contract.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Bug fixes (each with a regression test):
- metadata strip parity across every marker placement: IPTC digitalSourceType
in XMP, the Samsung post-EOI trailer, the China TC260 AIGC block in EXIF
UserComment, a bare AIGC block in a non-standard APP segment, and the ISOBMFF
EXIF path (AIGC + xAI) are all now stripped -- anything a scanner flags, the
strip reaches
- Samsung genAIType detected when its trailer sits past the 512 KB scan window
(file-tail read on large photos)
- crashes on edge inputs: Gemini detector on images with a short side < 16px,
footprint_mask on a zero-size ndarray, the humanizer on chromatic_shift >=
width, and the CLI on unreadable/corrupt/empty input (clean error, not a
traceback)
- WebP written losslessly (cv2 quality 101), not lossy at 100
- the IPTC digitalSourceType algorithmicMedia (procedural, not trained on
sampled data) is no longer flagged as AI-generated, so clean procedural
content is not scrubbed
- c2pa source-type: compositeWithTrainedAlgorithmicMedia is checked before the
bare algorithmicMedia token, so an AI-enhanced composite is not misclassified
Detection:
- integrity-clash coverage now normalizes ByteDance / Canva / ElevenLabs /
Black Forest Labs, so a transplanted manifest next to an independent
conflicting stamp is caught; the generic China TC260 AIGC label is attributed
to a co-present TC260 vendor, so a legit Doubao image (its own C2PA + TC260
label) does not clash (corpus-validated: 0 new clashes on 5000 carriers)
CLI:
- batch exits non-zero (with a warning) when any image errors or a GPU-missing
SynthID scrub is skipped, and copies the input through so the output dir stays
complete -- it used to always exit 0 and could silently drop files
Perf:
- GeminiEngine reused as a process-wide singleton with a precomputed template
ladder: -24% on the identify sparkle path, detection byte-identical
Internal: one shared _ai_exif_targets rule set feeds both EXIF scrubbers so
their coverage cannot drift; docs synced; maintain.sh hardened so the uv-secure
internal teardown crash no longer aborts the gate (still fails on a real finding).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Two AI-provenance metadata types mined from the retained corpus that
identify previously read as no-signal:
- Dreamina (ByteDance's international Jimeng brand) signs C2PA as
"Bytedance Pte. Ltd." with a "Dreamina/x.y" claim generator and NO
digitalSourceType, so the generator name is the only AI signal. Add a
C2paAiVendor row with a new asserts_ai flag (identity-AI: presence
asserts AI without trainedAlgorithmicMedia) plus the derived
C2PA_IDENTITY_AI_ORGS view, folded into identify's c2pa_is_ai. Keyed on
the Dreamina generator token, not the "Bytedance Pte" issuer, so non-AI
CapCut edits signed by the same entity stay unattributed. 7/7 corpus
files now attribute to ByteDance.
- Tencent Cloud's TC260 AIGC variant uses a ServiceProvider/ServiceUser
schema (vs the producer-side ContentProducer schema), embedded in EXIF
ImageDescription; add those field names to _TC260_FIELDS so the generic
{"AIGC":{...}} gate accepts it. 11/11 corpus files now flagged.
Test-first: reproducing tests in test_identify.py / test_metadata.py.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Resolve 10 code-review findings on the v0.14.0 localize->fill path, several
release-blocking:
- gemini: build the removal mask from the decision's provenance-aware region
instead of a strict internal re-detect. A relaxed/assume_ai sparkle was
re-demoted by the FP gate into a None mask and reported removed while left in
the image; this also drops the redundant double-detect.
- registry: report a mark removed only when a fill actually happened (remove()
returns a None region for an empty mask), so a no-op is never claimed.
- api/cli: add write_noop so the CLI `visible` no-mark path writes nothing and
cannot clobber a pre-existing -o file (was write-then-unlink -> data loss);
create output.parent; skip the same-file copy (SameFileError on in-place).
- cli: catch the missing migan/lama backend RuntimeError on the visible/all
paths (matches `erase`); route the single-mark relaxation through the shared
resolve_relax instead of an inline copy.
- metadata: keep_standard=False no longer takes the AI-only lossless JPEG
short-circuit (it left standard metadata); defer a malformed-marker JPEG to
the PIL fallback instead of reporting a partial strip as complete.
- invisible: register the HEIF opener before Image.open (HEIC --force) and
RGB-convert before the PNG temp (CMYK JPEG).
- pill: normalize via to_bgr so a 4-channel BGRA array cannot crash cvtColor.
Regression tests for each; docs synced (resolve_relax, write_noop,
best_auto_mark -> detect_marks).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
- Replace reverse-alpha removal with localize -> fill (template-free mask + one
shared cv2/MI-GAN/big-LaMa fill) for every mark; drops the colour-shift / dark-pit
failure modes, version-robust to a moved or re-rendered mark
- Separate perception/decision/action: engines report Candidates, a pure
decide(candidates, Context) arbiter owns all policy (sensitivity + provenance +
pill gate), remove_auto_marks orchestrates -- behavior-preserving (corpus 46/46/92)
- Three orthogonal knobs replace --method: --backend cv2|migan|lama,
--sensitivity auto|strict|assume-ai, provenance (auto from metadata)
- Add high-level api.remove_visible / visible_provenance (lazy top-level re-export);
visible --mark auto delegates to it so CLI and library share ONE path
- Read+write HEIC/AVIF on the pixel path via pillow-heif; imwrite preserves the input
format at max quality (JPEG q100/4:4:4); a no-op copies the original bytes verbatim
- Lossless byte-level JPEG metadata strip (no DCT re-encode); consolidate the two
remove_ai_metadata into one, delete legacy noai/cleaner + best_auto_mark
- Bump 0.13.0 -> 0.14.0
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Mined from the retained corpus 2026-06-22 (open-world EXIF/PNG-text/XMP scan,
minus the registry): three AI image generators that stamp a plain generator
name and no C2PA, so identify read them as no-signal -- and under the P0#5
no-signal skip would have skipped the scrub.
- NovelAI (anime SD): PNG tEXt Software/Source/Title. exif_generator now reads
PNG text chunks (via img.info), not only EXIF/XMP.
- Reve (reve.com): EXIF Software / XMP CreatorTool. Token is the full
"reve.com", not bare "reve" (would false-fire on "forever"/"reverie").
- Aphrodite AI: EXIF Make / Software.
Detection/removal parity: NovelAI stamps an AI-shaped VALUE under a non-AI KEY
(Title/Source), which _is_ai_key alone keeps. New _is_ai_value drops a text
chunk by value-token match on removal, mirroring exif_generator -- else the
cleaned file still read as NovelAI (verified on a real corpus file).
Tests: TestExifGenerator gains NovelAI PNG-text, Reve, Reve-not-overmatched,
Aphrodite, and a NovelAI detect/remove parity regression. Docs synced
(module-internals, watermarking-landscape, CLAUDE.md).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Closes a documented coverage gap (P2#9): an AI Software/Make/Artist/ImageDescription
token in an EXIF item (its TIFF bytes live in mdat/idat) survived remove_ai_metadata
because the top-level box stripper and (absent pillow-heif) the PIL EXIF reader can't
reach it. New isobmff.blank_ai_exif_tokens finds EXIF TIFF blocks by their II/MM
byte-order header, validates each with piexif (a coincidental II/MM run in pixels
won't parse as a TIFF IFD, so it's ignored), and overwrites any AI_GENERATOR_TOKENS-
bearing value with same-length spaces -- so box sizes and iloc offsets stay valid and
the coded image is untouched (mirrors blank_ai_xmp_packets; no iinf/iloc surgery, no
exiftool dep). Camera/editor EXIF without an AI token is preserved. Wired into
remove_ai_metadata's ISOBMFF path. Covers the realistic AI-generator-token case; xAI-
signature-in-meta-box-EXIF (Grok is JPEG-only) stays out.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
- AIGC: parse the bare ``AIGC{...}`` blob form (label glued to its JSON in a
JPEG APP segment near the JFIF header), and scan both raw-JSON forms in one
fall-through loop so a quoted ``"AIGC"`` later in an XMP packet no longer
shadows a real bare label earlier in the file (3 files read unknown before).
- Integrity clash rule 2: a camera device + an AI marker from the SAME C2PA
manifest (Google Pixel Magic Editor / Pixel Studio edit chain) is a legitimate
edit chain, not a contradiction. Fire only when the AI marker's source is
independent of the camera's manifest; pure cameras (Leica/Sony/Nikon) are
unaffected (2 Pixel files mis-flagged before).
- New c2pa_cloud_manifest detector: surface a C2PA 2.4 Durable Content
Credentials cloud-manifest reference (Adobe cai-manifests.adobe.com) as a
medium provenance signal when the embedded manifest is stripped. Provenance
only, never asserts is_ai (2 files read fully unknown before).
identify reuses its already-loaded scan head for the cloud check (no second
read). +7 tests; CLAUDE.md + README synced.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Apply fixes from a full-repo review (code, tests, docs).
Security / correctness:
- Clamp attacker-controlled PNG/caBX chunk lengths to the remaining file
size in metadata.py and noai/c2pa.py (a malformed length no longer drives
a multi-GB read); skipped chunks seek instead of read.
- noai/isobmff.strip_c2pa_boxes is now fail-safe on a malformed box: return
the original bytes with a warning instead of silently truncating the tail,
so metadata --remove can no longer emit a corrupt file.
- doubao_engine._fixed_alpha_map clamps the glyph box to the image (no crash
on degenerate width-vs-height).
- watermark_remover._run_region_hires gates the phaseCorrelate offset on
response and magnitude (a spurious shift no longer garbles text) and drops
the generator after a CPU fallback (no MPS/CPU device mismatch).
Robustness:
- gemini_engine, doubao_engine, region_eraser normalize grayscale and RGBA
inputs to BGR at the engine entry points.
- image_io.imwrite returns False on an unwritable path (matches cv2).
- invisible_engine guards a None imread result before use.
- trustmark_detector._decoder uses a double-checked threading lock.
- ctrlregen.tiling.tile_positions raises on overlap >= tile.
- humanizer chromatic shift no longer wraps opposite-edge pixels.
- identify OpenAI caveat keyed on the normalized vendor, not a substring.
- Remove the dead "visible --detect-threshold" CLI option.
- publish.yml verifies the release tag matches the package version.
Docs:
- README strength 0.05 to 0.10; .env.example HF_TOKEN marked optional;
doubao_capture README updated to reverse-alpha-only; CLAUDE.md synced with
the new behaviors and the batch command.
Tests: new test_security_clamp.py for the read clamp and isobmff fail-safe;
erase CLI coverage; integrity-clash rule 2 end-to-end; multi-tag EXIF
survival and cross-format strip guards; channel/size, tiling, humanizer, and
imwrite regressions. Full suite 493 passed, 2 skipped; ruff and pyright src/
clean.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A corpus audit surfaced China TC260 AIGC-labeled images that `identify`
missed. Three detection gaps in `aigc_label`, all fixed:
- raw-JSON `{"AIGC":{...}}` in JPEG EXIF (UserComment): brace-matched from
the scan head with `json.raw_decode`, gated on a TC260 field like the
PNG-chunk path. (Doubao-class output via that export surface.)
- XMP attribute form `TC260:AIGC="{...}"` (PicWish): folded into the
element regex as a second alternation.
- TC260 XMP packet appended after a large `IDAT`, past the 1 MB scan
window: `scan_head` now appends late PNG metadata chunks via
`_png_late_metadata`, mirroring the existing ISOBMFF late-box scan.
Adds `scripts/corpus_gap_scan.py`: runs `identify` over a corpus, writes
the per-file report CSV, and flags `unknown` files that carry a known
marker in their metadata region (the audit that found these gaps).
Scanning only the metadata region — not the whole file — avoids the
random short-token collisions inside compressed PNG/JPEG streams.
On the local corpus this lifts 3 files from `unknown` to AI (China AIGC)
and leaves zero false gap candidates. Synthetic piexif/PngInfo fixtures
cover all three forms.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
* fix(trustmark): gate detection on re-encode durability to kill false positives
TrustMark's wm_present flag is a BCH validity check that spuriously
validates on a content-correlated fraction of un-watermarked images
(AI textures trip it more than camera photos). On a 1343-image set all
20 raw detections were false, several on Gemini/OpenAI/Doubao output that
cannot carry Adobe's watermark, with random-bytes secrets.
A genuine TrustMark is a durable soft binding that survives re-encoding,
so detect_trustmark now re-decodes after a mild JPEG round-trip and
requires the same schema both times. Every observed false positive
collapsed under this gate; the second decode runs only on the rare hit.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* feat(identify): Samsung Galaxy AI, FLUX, ByteDance C2PA; fix C2PA substring FP
Detection extensions verified on real signed files (2026-05-29):
- Samsung Galaxy AI: signer attribution via a new _SIGNER_C2PA_PLATFORM
(Samsung Galaxy / ASUS Gallery) kept separate from the capture-camera
_DEVICE_C2PA_PLATFORM so a Galaxy AI edit (device cert + AI source type)
does not trip the camera-vs-AI integrity clash. Plus metadata.samsung_genai:
the proprietary genAIType marker in PhotoEditor_Re_Edit_Data, a medium-
confidence AI-editing signal (samsung_only branch).
- Black Forest Labs (FLUX) and ByteDance Volcano Engine (Doubao/Jimeng)
added as C2PA issuers + issuer->platform mappings.
- fix: C2PA presence required only the bare 4-byte 'c2pa' substring, which
false-positives on compressed pixel data (a recompressed PNG IDAT re-flagged
C2PA after its manifest was correctly stripped). New c2pa_marker_in() requires
the JUMBF wrapper (jumb+c2pa) or the C2PA uuid box; applied in identify +
metadata. Verified: all 535 real C2PA files carry jumb.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* fix(doubao): gate detection on text structure to cut ~95% of false positives (#23)
Coverage alone over-fired: any textured bottom-right corner cleared the
threshold, so the detector false-positived on ~28% of arbitrary images.
The real '豆包AI生成' mark is six glyphs in one row, so detect now also
requires the text-structure signature (_glyph_structure): many connected
components, no single dominant blob, concentration in a thin horizontal
band. False positives dropped 343 -> 17 across the corpus while keeping
real-mark recall and the doubao-1.png sample. Also accept a no-op force
kwarg for remover-interface symmetry.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* feat(samsung): add Samsung Galaxy AI visible-badge remover
New samsung_engine.py removes the bottom-left sparkle + localized
'AI-generated content' badge that Galaxy AI tools stamp. Mirrors the
Doubao locate->mask->inpaint pattern but bottom-left, with a dual-polarity
top-hat mask (the badge is light-on-dark or dark-on-light). Detection gates
on a band + left-anchor signature (the Doubao CJK-component gate does not
transfer: Latin badge letters connect into few blobs). Explicit-only --
tuned on few real badges with a ~4% FP floor, so it is not used in auto.
Synthetic byte-blob fixtures (real badges are user content, not shipped).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* feat(visible): unified known-watermark registry + LaMa inpaint backend
watermark_registry.py is a single catalog of known visible marks, each
tying {usual location, in_auto flag, recovery strategy, detect adapter,
remove adapter}: gemini (reverse-alpha, exact), doubao, samsung. cmd_visible
is now registry-driven (best_auto_mark for --mark auto; mark_keys() feeds the
CLI choices) -- the per-mark _run_doubao/_run_samsung helper branches are gone.
Cross-engine confidences are not comparable, so the gemini adapter applies the
corpus-validated 0.5 sparkle threshold for auto arbitration (its engine flag is
loose and weakly fired ~0.36 on Doubao text, hijacking auto).
--backend auto|cv2|lama chooses background reconstruction for the mask-based
marks; auto = LaMa when onnxruntime is present, else cv2. For LaMa the mask is
the FILLED glyph bounding box (sparse glyph masks leave anti-aliased edges
behind). cv2 stays the zero-dependency fallback.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* docs: watermark registry, Samsung/FLUX/ByteDance detection, LaMa backend, trustmark gate
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* feat(doubao): exact reverse-alpha removal from captured alpha map
The Doubao '豆包AI生成' mark is a fixed semi-transparent white overlay, so
given its alpha map the original pixels are recovered exactly:
original = (wm - a*logo)/(1-a) -- no inpaint hallucination.
The alpha map + logo colour were solved from real black+gray Doubao captures
on a controlled background: on black captured = a*logo, and the black/gray pair
solves a per-pixel without assuming the logo colour (a_max~0.65, logo near-white);
the white capture cross-validates (mark vanishes to a flat fill). Bundled as
assets/doubao_alpha.png + geometry constants.
remove_watermark_reverse_alpha applies it scaled to image width; exact at the
captured width, so the registry routes doubao through it only when
reverse_alpha_available (width within the calibrated band) and the mark is
detected, falling back to mask inpaint (cv2/LaMa) otherwise. A light residual
inpaint cleans the sub-pixel rescaling error. Add captures at more resolutions
to widen exact coverage.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* refactor(visible): reverse-alpha only -- drop inpaint removal + heuristic detection
Per the principle that we only remove/detect what we can do exactly, the
visible-mark path is now reverse-alpha only:
- Doubao detect is reverse-alpha-consistent: match the bundled alpha glyph
silhouette against the corner via TM_CCOEFF_NORMED (DETECT_NCC_THRESHOLD 0.4)
-- keys on the '豆包AI生成' SHAPE, not coverage/structure heuristics. FP
7/1243 (0.6%). Removes the cv2 inpaint path + the _glyph_structure gate.
- Registry is reverse-alpha only: dropped the cv2/LaMa backend (_glyph_remove,
_lama_box_inpaint, default_backend, --backend) and the Samsung entry. Doubao
outside the alpha resolution band is skipped, never inpainted.
- Removed samsung_engine.py + tests + --mark samsung (no alpha map captured;
Samsung C2PA/genAIType metadata detection in identify is unaffected).
- The universal erase --region (cv2/LaMa) is unchanged -- arbitrary-region
inpainting stays a user-directed tool, separate from the known-mark registry.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* feat(doubao): NCC sub-pixel alignment -> reverse-alpha at any resolution
A pure width-scale of the captured alpha map is only sub-pixel-accurate at the
captured width and leaves a faint ghost elsewhere. remove_watermark_reverse_alpha
now registers the alpha glyph to the actual mark via a TM_CCOEFF_NORMED
scale+position search (_aligned_alpha_map) before inverting the blend, so the
single 2048 capture works at any resolution -- verified clean on the 1773x2364
(3:4) corpus size, the biggest coverage gap (23 files).
reverse_alpha_available is now just 'asset present' (no width band); the registry
still gates removal on detect so a clean corner is never touched. Drops the
_ALPHA_WIDTH_TOLERANCE gate.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* fix(doubao): keep native recovery exact -- fixed geometry at captured width
Integer-pixel NCC alignment landed ~1px off at the captured width, degrading the
otherwise-exact native reverse-alpha (synthetic recovery error 0.94 -> 1.39).
remove_watermark_reverse_alpha now uses exact width-relative geometry within
_ALPHA_NATIVE_BAND of the captured width and the NCC search only off it -- best
of both: native back to 0.94, other resolutions still aligned.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* fix(doubao): harden alignment -- try fixed+aligned, keep least residual (56/56)
On a faint/busy-background mark the NCC alignment peak can wander a few px off
the true mark and leave a residual (2/56 real corpus files). Off the captured
width, remove_watermark_reverse_alpha now builds BOTH the fixed-geometry and the
NCC-aligned alpha map, applies each, and keeps whichever leaves the least
residual mark (re-detect confidence on the bare reverse-alpha) -- geometry wins
on faint marks, alignment on clear ones, no magic threshold. Real-file round-trip
now removes 56/56 detected Doubao clean across every corpus resolution (was 54).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* perf(doubao): skip residual inpaint at native width for exact recovery
At the captured width the fixed-geometry reverse-alpha is pixel-exact, so
inpainting over it only replaced exactly-recovered interior pixels with a
cv2 hallucination -- measured worse on a textured background (native error
vs true bg 1.6 reverse-alpha-only vs 2.6 with the old always-on
full-footprint inpaint). Native now returns the bare recovery untouched;
off-native, where NCC alignment is only sub-pixel-approximate, the footprint
inpaint stays to clean the seam. Real round-trip still 56/56 across all
corpus resolutions; negatives 0/60, Gemini unaffected.
Add test_native_returns_exact_reverse_alpha_no_inpaint as the regression
guard. Sync CLAUDE.md + README (the table cell and prose described the
pre-NCC "skipped off native / cv2-LaMa" behavior, now stale). Gitignore the
session scheduled_tasks.lock, and add the text-protection research note.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
remove_ai_metadata now writes JPEG at quality 95 with 4:4:4 (no chroma
subsampling) instead of the lossy PIL defaults (q75, 4:2:0), and preserves
WebP losslessly instead of silently rewriting it as PNG.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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>
HEIF/AVIF store XMP as a meta-box `mime` item whose bytes live in mdat/idat, out
of reach of the top-level uuid/jumb box stripper. An AI-label XMP packet there
(TC260 AIGC, IPTC "Made with AI", IPTC 2025.1) was therefore left in place.
isobmff.blank_ai_xmp_packets locates each XMP packet by its <?xpacket begin ...
end?> delimiters and, if it carries an AI marker (_AI_LABEL_MARKERS), overwrites
it with spaces of the SAME length. Equal length means no box size or iloc offset
shifts -- the coded image stays bit-for-bit intact, the item stays structurally
valid, only the AI label content is destroyed. Plain (non-AI) XMP is left alone,
mirroring the top-level XMP-uuid content match. Wired into remove_ai_metadata's
ISOBMFF branch after strip_c2pa_boxes.
Chosen over exiftool (a non-bundled binary dep) to stay pure-Python and
droplet-compatible; over full iinf/iloc surgery to avoid offset-rewrite
corruption risk. The AI labels we target are all XMP, so this closes the
practical gap. An Exif *item* inside the meta box (rare) still needs iinf/iloc
surgery or exiftool -- documented.
4 new tests (TestMetaBoxXmpBlanking): AI packet blanked (same length, marker
gone, surrounding image bytes intact), plain XMP preserved, no-packet no-op, and
end-to-end remove_ai_metadata on a .heic.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Provenance detection no longer relies on a fixed first-MB read. In a streaming /
non-faststart MP4 the C2PA manifest sits AFTER a multi-megabyte mdat, beyond the
1 MB scan window, so it was missed.
- isobmff.scan_c2pa_region(path): a file-seeking top-level box walker that
returns the payloads of uuid/jumb (provenance) boxes, seeking past mdat by
size without reading it -- works on multi-GB files. Returns b"" for
non-ISOBMFF or on read error. Mirrors the box-size encoding of the existing
in-memory _iter_top_level_boxes (largesize / size==0).
- metadata.scan_head(path, size): the shared input for every C2PA/AIGC/IPTC
byte scan -- first __TEXT __DATA __OBJC others dec hex bytes plus, for ISOBMFF, the late provenance-box
payloads. Behavior-neutral (f.read(size)) for non-ISOBMFF inputs.
- Routed all six metadata scan sites (has_ai_metadata, aigc_label,
iptc_ai_system, synthid_source, exif_generator XMP, get_ai_metadata
soft-binding) and identify's head read through scan_head.
6 new tests: late box found by scan_c2pa_region / scan_head, the fixed window
provably misses it, non-ISOBMFF -> b"", front-placed (faststart) regression.
The remaining gap stays documented: EXIF/XMP stored as items inside the meta
box (AVIF/HEIF stills) still needs meta-box surgery or exiftool.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
remove_ai_metadata now handles non-ISOBMFF audio/video (which the box walker
can't reach) by shelling out to ffmpeg with a lossless stream copy
(`-map_metadata -1 -map_chapters -1 -c copy`): codec data is untouched, only
container tags/chapters (ID3 / RIFF / Vorbis comments / EBML tags) are dropped.
Requires ffmpeg on PATH; raises a clear RuntimeError if absent or if ffmpeg
can't parse the input (instead of crashing in the image path).
Verified end-to-end: a real ffmpeg-made WAV/MP3 with a "Suno AI" title tag ->
tag gone, audio bytes preserved.
NOT built (evaluated, deliberate): Resemble PerTh audio *detection* --
`get_watermark()` returns a raw bit array with no presence/confidence flag, so
reliably telling watermarked from clean needs Resemble's fixed payload or a
confidence API (neither public; no real sample to calibrate). Same wall as the
SynthID pixel detector. AVIF/HEIF meta-box EXIF/XMP stripping also stays a gap
(needs exiftool, a non-installed binary). Both documented in CLAUDE.md.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds Trufo, Overlai, MarkAny, Mentaport, LumaTrace, VerdaAI, ContentLens, ISCC
(io.iscc content code), and Adobe ICN fingerprint to C2PA_SOFT_BINDINGS, and
notes AIWatermark wraps Meta PixelSeal. All `alg` prefixes verified against the
official c2pa-org/softbinding-algorithm-list registry.
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>
remove_ai_metadata now scrubs AI tags from the JPEG EXIF instead of passing
the block through wholesale. Closes the v0.5.5 follow-up: the xAI/Grok
Signature + UUID-Artist pair was detected but not removed.
- metadata._scrub_ai_exif(): deletes the xAI signature pair and any
Software/Make/Artist/ImageDescription tag carrying an AI_GENERATOR_TOKENS
token (so Ideogram's Make="Ideogram AI" is scrubbed too), keeping genuine
camera/editor EXIF intact.
- Shared _is_xai_signature_pair / _exif_text helpers (module-level compiled
regexes) are now the single source of truth, used by both xai_signature
and _scrub_ai_exif.
- Tests: Grok signature stripped on JPEG output, Ideogram Make stripped,
real-camera Make ("Apple") preserved. 325 passing.
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>
data/samples/doubao-1.png is the real #13 sample: carries the China TC260
<TC260:AIGC> XMP label and a visible '豆包AI生成' text mark (bottom-right).
Grounds the AIGC detection on a real file (alongside the synthetic tests)
and serves as the fixture for visible-watermark removal work.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Collected live samples from three popular generators we lacked:
- Ideogram tags its downloads with EXIF Make="Ideogram AI" (no C2PA, no
SynthID, no imwatermark) -- the Make tag is its only signal. exif_generator
only read Software/Artist/ImageDescription, so it missed this; now reads
Make too. Real cameras put "Apple"/"Canon" in Make (no AI token), so this
stays low-false-positive. 4 originals ingested.
- Recraft (PNG export) and Krea hosting FLUX 2: downloads carry NO detectable
signal -- no C2PA/EXIF/IPTC, and notably no imwatermark despite Krea running
FLUX. identify correctly reports 'unknown'. Both ingested as neg fixtures.
Lesson recorded in CLAUDE.md: the imwatermark detector fires only on pristine
output from a pipeline that runs the encoder (diffusers default, official BFL),
not from re-hosts (Krea/Stability) or re-encoded exports (Recraft/Canva).
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>
get_ai_metadata opened the file with PIL unguarded, so a HEIC (or any
format PIL can't open without optional plugins) raised
UnidentifiedImageError instead of falling through to the binary scan --
unlike has_ai_metadata, which already guards. Wrap the open in
except Exception and continue to the C2PA/IPTC path. Regression test
feeds an unopenable .heic shell and asserts no raise.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Detect SynthID-bearing images via their C2PA companion: a manifest signed by a
SynthID-using vendor (Google/OpenAI) on AI-generated content implies an
invisible SynthID pixel watermark. Verified end-to-end against the vendor
oracles (openai.com/verify, Gemini "Verify with SynthID").
- metadata: synthid_source() + synthid_watermark verdict in get_ai_metadata,
surfaced as a `metadata --check` callout. Format-agnostic (PNG caBX parser +
JPEG/WebP/AVIF/HEIF/JXL binary scan).
- constants: SYNTHID_C2PA_ISSUERS {Google, OpenAI}; +opened/placed actions.
- c2pa: single CBOR-aware parser (_cbor_text_after) replaces glitchy regex
(fixes fGPT-4o claim_generator); removed duplicate _scan_png_c2pa_chunk from
metadata; shared synthid_verdict / synthid_vendors_in helpers.
- corpus: scripts/synthid_corpus.py ingest tool + data/synthid_corpus/
(manifest tracked, images gitignored) for a labeled reference set.
- tests: +38 across C2PA parser internals, extract/inject round-trip, ISOBMFF
container stripping, all IPTC AI markers, and invisible watermark strength
tiers (SynthID/StableSignature/TreeRing/StegaStamp/RingID/RivaGAN/...).
Pixel-level SynthID detection remains out of reach locally (Google's decoder is
proprietary); a from-scratch spectral pilot confirmed it does not separate real
content. See CLAUDE.md for the full evaluation.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
SD-1.5 dreamshaper at 768 px did not defeat SynthID v2 on Gemini 3 Pro
outputs (verified May 2026 via Gemini app's "Verify with SynthID"). Switch
the default invisible engine to SDXL at 1024 px, matching the raiw-app
production config (strength 0.05, steps 50). Drop the SD-1.5 pipeline.
Metadata layer: add C2PA UUID and IPTC AI marker byte-scan detection
across all formats, plus an ISOBMFF box walker (noai/isobmff.py) that
strips top-level C2PA uuid and JUMBF jumb boxes from AVIF/HEIF/JPEG-XL
containers without re-encoding.
README gets a Legal table and a Threat-model section about SynthID v2's
136-bit payload. CLAUDE.md tracks the SD-1.5 regression as historical
context.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
- CLI with visible, invisible, all, metadata, and batch commands
- Gemini watermark removal via reverse alpha blending
- Invisible watermark removal via diffusion regeneration (SynthID, TreeRing)
- AI metadata stripping (EXIF, PNG text, C2PA)
- Face protection (YOLO/Haar) and analog humanizer
- 137 tests covering all CLI modes and core engines
- Ruff and Pyright clean