Merge remote-tracking branch 'origin/main' into docs/arxiv-paper-review

# Conflicts:
#	.claude/settings.json
#	docs/installation.md
#	docs/supported-signals.md
#	docs/synthid.md
#	docs/verification-plan.md
#	docs/watermarking-landscape.md
#	pyproject.toml
#	src/remove_ai_watermarks/identify.py
#	uv.lock
This commit is contained in:
Victor Kuznetsov
2026-08-26 12:39:05 -07:00
84 changed files with 6888 additions and 1666 deletions
+68 -5
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@@ -17,7 +17,7 @@ defaults. This page focuses on choosing the right command.
| `verify-openai-synthid` | `remove-ai-watermarks[verify]`, API access, and `OPENAI_API_KEY` |
| Visible signals in `identify` | `remove-ai-watermarks[visible]` (`pixels` is the minimal runtime) |
| Open DWT-DCT signals in `identify` | `remove-ai-watermarks[detect]` |
| Adobe TrustMark signals in `identify` | `remove-ai-watermarks[trustmark]` |
| Adobe TrustMark signals in `identify` on Python 3.11-3.12 | `remove-ai-watermarks[trustmark]` |
| `visible` and `erase` with OpenCV | `remove-ai-watermarks[visible]` (`pixels` is the minimal runtime) |
| `visible` or `erase` with MI-GAN | `remove-ai-watermarks[migan]` |
| `visible` or `erase` with big-LaMa | `remove-ai-watermarks[lama]` |
@@ -27,7 +27,7 @@ defaults. This page focuses on choosing the right command.
| `video visible`, `video all`, and visible/all batch modes | `remove-ai-watermarks[video]` plus ffmpeg on PATH |
| `video invisible` and `video all --invisible` | `remove-ai-watermarks[video,diffusion]` plus ffmpeg on PATH |
| HEIC/HEIF/AVIF pixel input | Add `remove-ai-watermarks[heif]` |
| Every production command and backend | `remove-ai-watermarks[all]` |
| Every production command and Python-compatible backend | `remove-ai-watermarks[all]` |
`batch` requires the same extra as its selected mode. Extras can be combined in
one installation, for example `remove-ai-watermarks[visible,detect,heif]`.
@@ -41,7 +41,15 @@ remove-ai-watermarks identify image.png
`identify` always inspects supported metadata. When pixel extras are installed,
it also evaluates supported visible and invisible pixel signals. When no signal
is found, it reports the origin as unknown. It does not claim the image is
clean.
clean. For C2PA files, the text report shows asset integrity, claim-signature,
signer-trust, and signer-validity results separately. Confidence follows the
binding: an intact asset binding and claim signature is high confidence, and an
unanchored or expired signer is reported as a caveat rather than a lower score,
because no trust anchor list ships with the reader. A failed asset binding or
signature, or a revoked signing credential, does not confirm the claimed origin. When a structured
C2PA soft binding is present, the report also names its exact algorithm and
signed value; removing the manifest does not remove the referenced pixel
watermark or content fingerprint.
Machine readable output:
@@ -191,6 +199,11 @@ remove-ai-watermarks metadata image.png --remove -o clean.png
When `-o` is omitted, removal overwrites the source. Standard metadata is kept
unless you pass `--remove-all`.
A quiet `--check` or a successful `--remove` is not a clean verdict. The command
only inspects and strips embedded AI metadata; a pixel watermark such as SynthID
has no local decoder once that metadata proxy is gone. `identify` reports the
same limit.
The command also supports the audio and video containers listed in
[supported signals](supported-signals.md). ffmpeg must be available for the
non-ISOBMFF audio and video path.
@@ -259,11 +272,17 @@ remove-ai-watermarks video metadata input.mp4 --check
remove-ai-watermarks video metadata input.mp4 --remove -o clean.mp4
```
As with the generic `metadata` command, a quiet check or a successful strip is
not a clean verdict: video SynthID is not decoded locally after the metadata
proxy is gone.
Supported containers are MP4, MOV, M4V, WebM, MKV, AVI, and FLV. The operation
delegates to the same verified metadata scanner and stripper as the generic
`metadata` command, so detection and removal stay in parity. Video and audio
streams are not transcoded. For MP4 and MOV, this includes the native TC260
`AIGC` key and JSON value stored in `moov.udta.meta.keys/ilst`. The inspector
`AIGC` key and JSON value stored in `moov.udta.meta.keys/ilst`, plus the
QuickTime-form `meta` variants Doubao's iOS export writes (a bare `meta` box
as a direct `moov` child, and a keyless `hdlr=mdir` metadata list). The inspector
seeks past a large `mdat` to find a tail `moov`. Removal stream-copies the
container in bounded chunks, converts supported top-level provenance boxes to
same-size `free` boxes, and blanks the TC260 key/value in place. Box sizes,
@@ -432,6 +451,50 @@ schedule, CFG 1.0 and CUDA, so every one of those flags existed only to be refus
several layers down. They are not parsed at all now, which fails at the point the
user can act on rather than after a model load.
### Restore operator-verified text
`--text-manifest` enables the experimental `vae-glyphs` post-pass. It reconstructs
the source with the Qwen VAE, blends 15% of that reconstruction into the normal
`qwen-zimage` result, erases the annotated candidate glyphs with LaMa, and composites
only the reconstructed glyph cores through source-derived silhouettes. It does not
run OCR or choose which strings are correct.
Install the combined extra and run only with an operator-verified manifest:
```bash
uv tool install --force "remove-ai-watermarks[text-restoration]"
remove-ai-watermarks invisible image.png -o clean.png \
--pipeline qwen-zimage --text-manifest verified-lines.json --force
```
``verified: true`` may also be set by an automated operator that attests
machine-verified geometry: stability-gated detector boxes inside sane caps. Such
operators should use the geometry-only schema 2, which carries no transcription
or script metadata.
Since 0.27.1 the global 15% Qwen-VAE fidelity-anchor blend is off by default: it
was measured to return detector-visible OpenAI SynthID on poster-scale manifests
(official Content Provenance API, 2026-08-19). `--fidelity-anchor` restores the
0.27.0 research behavior; text-box fidelity lost by the default is well under one
MAE point on the measured fixtures.
The manifest is a JSON object with `verified: true`, decoded RGB dimensions,
`source_pixel_sha256`, and a non-empty `lines` array. Schema 1 is retained for
manually reviewed annotations: each line has an integer `[x1, y1, x2, y2]` box,
exact `text`, a non-empty `script`, and an optional angle from -30 to 30 degrees.
Schema 2 is geometry-only: each line has the box and optional angle, with no
required `text` or `script`. Lines must be in top-to-bottom, left-to-right order.
The hash binds the annotations to decoded RGB geometry and pixels, so metadata-only
container changes remain valid while a resized or edited source fails closed. The
experimental helper
`remove_ai_watermarks._internal.text_restoration.source_pixel_sha256` computes it.
This mode is supported only by `qwen-zimage` at native geometry with
`humanize=0`, `unsharp=0`, and adaptive polish disabled. `all` also accepts the flag,
but its manifest must match the pixels entering the invisible stage; if visible-mark
removal changes those pixels, the hash check rejects the run. One oracle verdict does
not certify another manifest, seed, model/runtime version, or output hash.
### Work with limited memory
Lower CUDA memory pressure:
@@ -463,7 +526,7 @@ It is a memory strategy, not a guarantee of better quality.
The `all` command and the `all` installation extra are separate concepts. The
command runs every applicable stage. Installing `remove-ai-watermarks[all]`
makes every production backend available; a smaller installation such as
makes every backend compatible with the active Python available; a smaller installation such as
`remove-ai-watermarks[visible,qwen-zimage]` can also run the command with fewer
optional backends.
+12
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@@ -7,3 +7,15 @@ This page records notices required by source dependencies and licensed derivativ
- The DWT-DCT implementation derives from ShieldMnt's
[`invisible-watermark`](https://github.com/ShieldMnt/invisible-watermark), licensed
under MIT. Its notice ships in `src/remove_ai_watermarks/licenses/invisible-watermark-MIT.txt`.
The decode path is a vectorized reformulation, not a transcription: it produces
the same bits and is checked against upstream's own decoder, but it no longer
corresponds line by line to `imwatermark/maxDct.py`. Diffing the two files will
show structurally different code, which is expected and does not mean the
derivation notice is stale.
## Licensed test fixtures
- `data/fixtures/provenance/adobe-trustmark-p.png` is Adobe's official
TrustMark Variant P example, licensed under MIT. Its source commit, digest,
and reproduced license are recorded beside the fixture in
`data/fixtures/README.md` and `data/licenses/adobe-trustmark-MIT.txt`.
+1 -1
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@@ -524,7 +524,7 @@ held by its masked ArcFace vector -- no original pixel copied.
drift, NOT a perfect face swap. Set expectations; PuLID/InstantID are the higher-fidelity (heavier)
paths if needed.
- **Value scales with strength:** at low strength (OpenAI 0.10) faces barely drift, so FaceID is
marginal; at the higher strength a hard vendor (Google 0.30) needs, FaceID earns its keep.
marginal; at the higher strength then used for a hard vendor (Google 0.30), FaceID earned its keep.
### Build plan (staged)
+10 -1
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@@ -12,9 +12,18 @@ Read this reference for environment setup, dependency recovery, CI behavior, and
The optional TrustMark decoder downloads weights into its installed package directory. After pruning that extra, a leftover weights directory can make availability checks see an empty namespace package. If Pyright reports an unknown `TrustMark` import and `find_spec("trustmark")` returns a loader-less spec, remove that regenerable remnant from the active virtual environment and resync.
### Known security-gate blocks
`maintain.sh` fails while PyPI ships no fixed release for a transitive CVE. Current case (triaged 2026-08-17): `lightning` 2.6.5, pulled only by the optional `trustmark` extra, carries PYSEC-2026-3624 (RCE via `load_from_checkpoint` on an attacker-crafted checkpoint). The vulnerable API is unreachable here, because the TrustMark decoder loads only its own pinned weights downloaded from the TrustMark release, never a user-supplied checkpoint. The upstream fix is merged but unreleased, and ignores are never added, so run and report the remaining core checks (Ruff, Pyright, tests) separately until a fixed `lightning` release lands; bump it with `uv lock --upgrade-package lightning` as soon as one does.
## CI
`.github/workflows/test.yml` runs Ruff, a cross-platform test matrix over the supported-Python floor and the latest supported minor with default plus development dependencies, and a separate job that installs ffmpeg on Ubuntu to run the full-clip video test. Diffusion and model-running tests skip in that matrix; metadata, identification, visible removal, the DWT-DCT decoder, and the OpenCV eraser remain covered across operating systems.
`.github/workflows/test.yml` runs Ruff, a test matrix over every supported Python
minor with default plus development dependencies, cross-platform coverage at the
oldest and newest minors, and a separate job that installs ffmpeg on Ubuntu to
run the full-clip video test. Diffusion and model-running tests skip in that
matrix; metadata, identification, visible removal, the DWT-DCT decoder, and the
OpenCV eraser remain covered across operating systems.
Keep `uv.lock` compatible with `uv sync --frozen`. Dependency pull-request checks use GitHub's merge result against current `main`; if `main` moves, merge it locally and rerun the full gate because a newer linter can expose stale directives in later code.
+1 -1
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@@ -22,7 +22,7 @@ to run the tool. Use the maintainer references only when changing the code.
| [Development](development.md) | Environment setup, dependency recovery, CI behavior, and fixture policy. |
| [Code provenance](code-provenance.md) | Required notices for licensed derivative work. |
| [Verification plan](verification-plan.md) | Verification methods, completed measurements, and remaining validation gaps. |
| [Release and distribution](release-and-distribution.md) | PyPI, Homebrew, Hugging Face Space, and release workflow. |
| [Release and distribution](release-and-distribution.md) | PyPI, Homebrew, Hugging Face Space, ComfyUI Registry, and the release workflow. |
| [Watermarking landscape](watermarking-landscape.md) | Vendor signals and detection approaches. |
| [SynthID technical reference](synthid.md) | Mechanism, provenance, robustness, regeneration. |
+20 -6
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@@ -1,6 +1,6 @@
# Installation
Python 3.10.1 or newer is required.
Python 3.11 through 3.14 are supported.
## Default metadata mode
@@ -87,6 +87,15 @@ removal, metadata stripping and every `identify` command still run anywhere.
Video SynthID regeneration is a separate VAE path and does still run on CPU or MPS;
it needs the `diffusion` extra, not this one.
The experimental verified-text post-pass additionally needs LaMa:
```bash
uv tool install --force "remove-ai-watermarks[text-restoration]"
```
That extra includes `qwen-zimage` and `lama`; it does not add OCR. Text strings and
line boxes must be reviewed before the run.
## Feature extras
Extras are composable. Install only the capabilities and file formats the
@@ -99,13 +108,14 @@ application actually uses:
| `visible` | Visible mark detection, OpenCV inpainting, and manual erasing | `pixels` | No |
| `video` | Visible video identification/removal and timestamp preservation | `visible`, PyAV | No |
| `detect` | Open DWT-DCT detection for Stable Diffusion, SDXL, and FLUX | `pixels`, PyWavelets | No |
| `trustmark` | Adobe TrustMark detection | trustmark | Yes |
| `trustmark` | Adobe TrustMark detection on Python 3.11-3.12 | trustmark | Yes |
| `verify` | Official remote OpenAI SynthID verification | OpenAI SDK | No |
| `diffusion` | Torch and Diffusers runtime; video SynthID regeneration | `pixels`, Torch, Diffusers | Yes |
| `migan` | MI-GAN ONNX fill backend | `visible`, ONNX Runtime | Model download, no Torch |
| `lama` | big-LaMa ONNX fill backend | `visible`, ONNX Runtime | Model download, no Torch |
| `qwen-zimage` | Invisible image-watermark removal, both CUDA-only profiles | `diffusion`, DiffSynth | Yes |
| `all` | Every production feature | All rows above | Yes |
| `text-restoration` | Opt-in verified Qwen-VAE glyph restoration | `qwen-zimage`, `lama` | Yes |
| `all` | Every production feature available on the active Python | All compatible rows above | Yes |
| `dev` | Tests, linting, typing, and upstream parity checks | `video`, `detect`, upstream invisible-watermark | Yes, for parity tests |
Dependency composition:
@@ -119,14 +129,18 @@ flowchart LR
migan --> visible
lama --> visible
qwen["qwen-zimage"] --> diffusion
text["text-restoration"] --> qwen
text --> lama
heif
trustmark
verify
```
`heif`, `trustmark`, and `verify` are independent branches. Combine them explicitly with
another feature when required. The `all` bundle contains every production
branch but never includes `dev`.
another feature when required. TrustMark requires NumPy 1.x, which has no
CPython 3.13 or 3.14 wheels, so that branch is available only on Python
3.11-3.12. The `all` bundle contains every production branch compatible with
the active Python and never includes `dev`.
Examples:
@@ -146,7 +160,7 @@ uv tool install --force "remove-ai-watermarks[detect,trustmark]"
# Official OpenAI SynthID verification
uv tool install --force "remove-ai-watermarks[verify]"
# Every production capability
# Every production capability compatible with this Python
uv tool install --force "remove-ai-watermarks[all]"
# An arbitrary minimal combination
+75 -7
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@@ -57,12 +57,42 @@ Invisible removal does not decode and delete a payload. It regenerates the
image through a diffusion pipeline. Faces, text, colors, and fine detail can
change even when the watermark is successfully disrupted.
Text, tables, and UI screenshots are the worst case for a forced scrub: the
model redraws glyphs as plausible-but-wrong shapes. Do not run the invisible
stage on such content unless a locally-detectable invisible signal exists.
The default `all`, `invisible`, and `batch` commands already skip it then, and
`visible` (which strips AI metadata by default) or `metadata` alone never
redraws a glyph outside the filled watermark box. `--force` is for content you
know carries a pixel watermark despite no local signal; on a clean screenshot
it only buys distortion. Preserving or pasting back the original text pixels
during a real scrub is deliberately not offered: an invisible watermark such
as SynthID lives in the pixels everywhere, including inside the glyphs, so
frozen text regions would keep the watermark
([text protection research](text-protection-research.md)).
`qwen-zimage` is the default profile and `sdxl-zimage` the only alternative.
Both are CUDA only and differ only in the global regeneration model: each
conditions that stage on a canny edge map, which preserves structure but not
identity or exact texture, and each then runs the same face stage.
`qwen-zimage` is the higher fidelity of the two. Both are large, slow, and may
still alter small text or difficult faces.
Existing face evaluations favor `qwen-zimage`, but there is no blanket fidelity
ordering across content types. A fixed-seed, three-scene text comparison at the
profile defaults found no stable winner: SDXL won one poster, Qwen won one, and
the Chinese sign tied. Both are large, slow, and may still alter small text or
difficult faces. The measurements and their OCR and oracle caveats are tracked
in [`data/evaluations/fidelity/`](../data/evaluations/fidelity/README.md).
A global Z-Image Turbo prototype preserved text substantially better at low
strength, but it has no useful cross-provider operating point and is not a
supported profile. Automatic text restorers also remain research-only:
fresh-font and silhouette variants visibly changed typography. The higher-fidelity
`vae-glyphs` route is available only as an experimental opt-in with verified strings
and line geometry. It builds its donor internally but still requires an independently
clean global anchor. Automatic OCR and line-box proposals are not reliable enough to
remove those requirements, and exact oracle results do not establish a general mask,
seed, runtime, or provider operating range. Qwen-Image-2.0 is hosted-only and exposes
no equivalent low-strength denoise control. Exact experiments, controls, and pass
rates are kept in
[`text-protection-research.md`](text-protection-research.md) and the
[`fidelity` evaluation record](../data/evaluations/fidelity/README.md).
### There is no local SynthID pixel detector in the package
@@ -114,6 +144,21 @@ measured 25.39 dB paired PSNR and a 1.058 motion-compensated temporal-residual
ratio. This is one carrier, not a universal guarantee; hashes and exact verdicts
are tracked in `data/evaluations/video-synthid-oracle.csv`.
### The invisible video path does not touch the audio track
`remove_video_invisible` regenerates the video stream and copies the source audio
verbatim: the extracted audio bitstream of input and output has an identical
sha256, measured on two carriers. It also strips every metadata marker, so the
output can report clean from `get_ai_metadata` and `identify_video` while carrying
an untouched generated audio track. Google's verifier scores audio and visual
tracks separately, and a track this path never modifies is a track it cannot have
cleaned.
Whether a given carrier's audio actually holds a mark the verifier reads has not
been established -- that needs a provider verdict, which has not been obtained.
Treat a clean local report on a clip with generated audio as unproven, not as a
guarantee, and check the audio separately when it matters.
The shipped engine streams sampled frames in bounded batches, computes its
fidelity metrics incrementally, and pipes regenerated pixels directly to
ffmpeg. Its frame and latent memory is therefore bounded by `--batch-size`
@@ -134,9 +179,14 @@ path has not yet answered.
The two profiles resolve an unset strength differently, because different things
were measured for each.
`qwen-zimage` reads it from image area, through the resolution-adaptive denoise
curve. The vendor is deliberately ignored: the curve, not the issuer, is what was
calibrated.
`qwen-zimage` reads unknown content from the resolution-adaptive denoise curve.
Measured provider cohorts instead take flat operating points: OpenAI `0.07675`,
Google `0.27`, and Microsoft InvisMark `0.15`. OpenAI and Microsoft add one full
observed cross-source boundary spread to the worst clean source; Microsoft's three
first-clean boundaries were `0.04125`, `0.055`, and `0.095`, giving `0.14875` before
rounding up. Google's candidate was separately repeated across three valid sources
and three accounts. The small corpora make these operating points, not universal
thresholds.
`sdxl-zimage` reads it from the C2PA issuer, on a flat ladder:
@@ -162,6 +212,15 @@ certified at a fixed seed. The live resolver is
| `qwen-zimage` | CUDA only, large model stack, and limited broad certification across seeds and content. |
| `sdxl-zimage` | CUDA only. Its strength ladder is flat per vendor, not a resolution curve, because flat values are what was measured. |
Only manually verified `vae-glyphs` is an optional production stage, and it is
experimental rather than a default.
OCR plus LaMa recovered literal poster text but changed fonts and worsened whole-image
fidelity. Restricting it to OCR-mismatched lines improved the tradeoff but still
left a local shadow on one poster. The published AnyText2 SD1.5 checkpoint
substituted Chinese characters and increased CER on the sign fixture. AnyText2XL
is not published, and the released wrapper truncates individual text lines after
20 characters.
The `controlnet`, `sdxl`, `qwen` and `default` profiles were removed, not aliased
onward: a retired name is rejected at parse time rather than routed into a profile
the caller never chose. There is no `--model`, `--steps`, `--guidance-scale`,
@@ -346,8 +405,17 @@ Diffusion, SDXL, and FLUX workflows. That decoder is sensitive to the carrier
and transformations. A negative result is not a universal negative.
The `trustmark` extra adds Adobe TrustMark decoding. The implementation retains
an additional JPEG re-encode gate because isolated decoder hits can otherwise
be content noise.
an additional JPEG re-encode gate and requires the binary payload and schema to
remain identical because isolated decoder hits can otherwise be content noise.
It accepts Variant P schemas 0-2. Variant Q requires a different model, and
schema 3 is rejected at the measured precision threshold. Its NumPy 1.x runtime
limits the extra to Python 3.11-3.12; the rest of the package remains supported
through Python 3.14. Through 0.29.0 the extra also resolves lightning 2.6.5
(PYSEC-2026-3624, no fixed release yet); the vulnerable `load_from_checkpoint`
path is unreachable here because TrustMark loads its checksummed checkpoints
with plain `torch.load`. Bump lightning and cut a patch release when a fix
ships. The calibration history is in
[module internals](module-internals.md#metadata-and-provenance).
A generic metadata-free AI-generated-image classifier is not shipped. It is a
separate open research task from provenance detection: the current Model 1
+208 -6
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@@ -42,6 +42,10 @@ Important contracts:
- `invisible` writes no output when no supported local signal is found, unless
`--force` is supplied.
- The two no-signal conditions currently share exit code `2`.
- A quiet `metadata --check` and a successful `metadata --remove` (same for
`video metadata`) end by repeating the `identify` limit: the pixel channel is
untouched and a watermark such as SynthID has no local decoder once its
metadata proxy is gone, so neither outcome is a clean verdict.
- Hard processing and write failures exit with code `1`.
- `all` can still write the completed visible and metadata stages when the
diffusion dependencies are unavailable, but exits with code `1` so the
@@ -158,7 +162,14 @@ Native MP4/MOV TC260 labels follow TC260-PG-20257A:
`moov.udta.meta.keys` maps an `AIGC` key to a raw JSON value in `ilst`.
[`_internal/isobmff.py`](../src/remove_ai_watermarks/_internal/isobmff.py) walks those
nested boxes by seeking, so detection reaches a tail `moov` without reading the
preceding `mdat`. The MP4/MOV/M4V/M4A removal path first validates the top-level
preceding `mdat`. Two Doubao iOS variants sit outside that normative placement
and are covered by the same walker (2026-08-17 corpus findings, both previously
undetected): a QuickTime-form `meta` box as a *direct* `moov` child (no FullBox
header, disambiguated by probing the child-box offset), and a QuickTime
`hdlr=mdir` metadata list under `udta.meta` whose `ilst` data items carry the
validated JSON with no `keys` box at all (content-validated, so only genuine
TC260 JSON matches; the keyless entry has no key name to blank, so its value
alone is spaced out). The MP4/MOV/M4V/M4A removal path first validates the top-level
box walk, then copies the source to a sibling temporary file in bounded chunks.
Supported C2PA/JUMBF/AI-label boxes become same-size `free` boxes with blank
payloads; TC260 removal changes the four-byte key to `free` and blanks only the
@@ -364,6 +375,75 @@ Regression coverage:
official `c2pa-python` reader first. Its byte-level PNG parser remains a fallback
for partial and synthetic fixtures that the official reader rejects.
Structured extraction is limited to the active manifest and the ingredient
manifests reachable from it. Validation is preserved as separate dimensions:
asset binding integrity, claim signature, signer trust, and signer certificate
validity. A matching asset hash and valid claim signature do not make an
untrusted or expired signer trusted, so those stay separate fields and separate
caveats -- but they do not lower confidence. `identify` assigns high confidence
when the asset binding and the claim signature both validate, medium confidence
to a claim that validated nothing (fallback parsing, unknown dimensions), and no
origin verdict to a binding failure, a signature failure, or a revoked signing
credential. The failed claim remains in the marker inventory and keeps the removal
gate fail-safe because a post-signing container edit can invalidate C2PA without
removing a declared pixel watermark.
Revocation reaches the disqualifying branch through `signer_validity`, not through
binding or signature. A check that read only the latter two returned a confident AI
verdict off a credential the issuer had disowned, with an empty `integrity_clashes`
-- quieter than a hash mismatch on the same file. Certificate expiry is deliberately
not disqualifying: an expired certificate does not imply the signed bytes changed,
and a signature actually made outside validity already arrives as
`claimSignature.outsideValidity`.
One rule, one place. `_validation_fields` maps status codes to the four dimensions
and also emits `c2pa_failed_codes`, the subset of failures that actually drove a
dimension to invalid; `c2pa_info_has_invalid_credential` maps those dimensions to
disqualified, and both the ingredient-reachability walk and the report consume that
single path. The displayed reason comes from `c2pa_failed_codes` rather than a
substring rescan of the full code list, so what a caller is shown as the cause
cannot become a looser rule than the verdict it explains.
The structured walk also treats an exact known AI product in a reachable
`claim_generator` as an AI assertion. This covers update chains where the active
manifest names only `c2pa-tool` while a validated ingredient names Dreamina, and
Firefly chains that identify `Adobe_Firefly` without repeating a digital source
type. Unreachable manifests remain excluded.
Reachable `c2pa.soft-binding*` assertions retain their exact `alg` and bounded,
printable block `value` in addition to the normalized vendor label. A block value
without its algorithm is not surfaced because it cannot be attributed to a
decoder or registry entry. `com.microsoft.invismark.1` uses that value as the
pixel-watermark identifier in Microsoft Paint output. An InvisMark soft binding
keeps the invisible-removal gate fail-safe even when the C2PA asset binding has
since become invalid, because metadata damage does not prove the pixel carrier
disappeared. `identify` retains the generic `soft_binding` signal for schema-1
compatibility and adds `invismark` as the stable pixel-removal signal.
Content-fingerprint soft bindings do not trigger pixel regeneration.
The SDK default enables trust verification but supplies no production trust
anchors. Consequently, an installation without an explicitly maintained C2PA
trust bundle reports every otherwise valid signer chain as untrusted --
`signingCredential.trusted` appears in no default installation, from any vendor.
Confidence therefore must not depend on it. It did from 0.27.0 through 0.30.0, which made
the high-confidence branch unreachable in production while a hand-built fixture
stamping `signingCredential.trusted` kept it green in the suite; measured on the
committed provenance fixtures, every C2PA file from OpenAI, Adobe and Black Forest
Labs came back untrusted, and an intact manifest scored the same medium as a
fallback parse that validated nothing. That collapsed the one distinction the
official reader exists to draw.
`tests/test_identify.py::TestIdentifyRealSamples::test_no_committed_fixture_reports_a_trusted_signer`
is the reachability guard: it asserts the fixtures really are untrusted and still
reach high confidence.
Read `untrusted` here as a missing input, not a finding: nothing was checked,
because there was nothing to check against. If a maintained trust bundle is ever
configured, that stops being true and the confidence mapping in
`_c2pa_credential_level` must be re-read, because only then does a failed trust
check mean the signer was rejected. Shipping or fetching an official trust bundle
requires a separate update, provenance, and availability policy; do not silently
convert `signingCredential.untrusted` into trusted based on a vendor-name match.
Vendor attribution comes from the registry in
[`_internal/constants.py`](../src/remove_ai_watermarks/_internal/constants.py). Derived
issuer and platform maps should not be maintained separately.
@@ -930,22 +1010,82 @@ the function it replaces does — no provenance means no relaxation, and an unkn
invisible target means scrub rather than skip.
The `detect` extra composes the shared `pixels` runtime with PyWavelets. Its
in-tree [`dwt_dct.py`](../src/remove_ai_watermarks/dwt_dct.py) decoder preserves
the upstream matrix algorithm without installing Torch or non-headless OpenCV.
The upstream MIT notice ships inside the wheel under `licenses/`.
in-tree [`dwt_dct.py`](../src/remove_ai_watermarks/dwt_dct.py) decoder reproduces
the upstream algorithm's output bit for bit without installing Torch or
non-headless OpenCV; the block scan is vectorized rather than transcribed, so
the file no longer reads line by line against `maxDct.py`. The upstream MIT
notice ships inside the wheel under `licenses/`.
`is_ai_generated` is `True` or `None`; absence of evidence is not reported as a
human-made verdict. `ai_source_kind` distinguishes fully generated content from
AI-enhanced composites when the source metadata provides that distinction.
TrustMark is reported as a watermark signal but does not by itself assert AI
origin because it can also protect human-authored content.
origin because it can also protect human-authored content. The decoder requests
binary mode, matching Adobe's Durable Content Credentials example, then requires
the same payload and schema after a quality-95 JPEG round-trip. Only Variant P
schemas 0-2 count as positives. Schema 3 is below the precision threshold: all
38 measured historical false-positive candidates used it, and six retained the
same false payload after re-encoding. The official Adobe Variant P schema-1
fixture in `data/fixtures/provenance/` is the positive regression control.
#### Why the DWT-DCT decoder looks the way it does
Two things in `dwt_dct.py` are load-bearing and neither is obvious from the code.
`_approximation` calls `pywt.dwt` twice instead of `pywt.dwt2`, and transposes
before each pass. A factorial ablation over both axes separates the two:
skipping the three detail bands `dwt2` computes and this code discards is worth
**4%**, while the transposes are worth **2.8x**, because pywt walks the axis it
transforms and on axis 0 of a C-contiguous plane that is a column walk. The
arithmetic saving is the intuitive explanation and it is the small term; four
independent profiles named it as the mechanism before the ablation contradicted
them.
Bit-identity is a hard requirement, not a preference. For uint8 input the exact
Haar LL value is a multiple of 0.5 and the bit test is `peak % 36 > 18.0`, a
threshold sitting exactly on a representable value that ~1 block in 72 lands on,
so a 1-ulp difference deterministically flips real bits. That is why the ~16x
available from a hand-rolled numpy Haar is unreachable rather than merely
untaken: pywt's C convolution contracts into an FMA that numpy has no ufunc for,
and `np.longdouble` is 64-bit on arm64 macOS.
Each pass is one flat `pywt.downcoef` call over a raveled strip rather than
`pywt.dwt(..., axis=1)[0]`, and the plane is processed in strips of `_STRIP`
block-rows so no full-plane float64 intermediate is ever materialized. The strip
height is not a tuned value: 8 through 64 all scored inside each other's noise
with unstable ordering, and only "strips at all" versus whole-plane matters.
`_approximation`'s even-last-axis check is load-bearing, not defensive. Haar's
filter is length 2, so an even row length keeps every pair inside its own row;
on an odd width the pairs walk across row boundaries and the reshape still
succeeds whenever the total is even, which would be wrong bits with no
exception. Both call sites are even by construction today, and
`TestRaveledHaarPass` pins both halves -- the `downcoef`/`dwt` equivalence,
which a pywt upgrade could take away, and the raise on an odd width.
Measured on a 1536x2816 image, all arms timed in one process: the decoder went
0.112 s (the original per-block Python loop) to 0.011 s vectorized to 0.007 s
with strips, and a warm `identify()` 1.757 s to 1.365 s on the first step and a
further 0.4% on the second. That last figure is the point at which this target
is finished: the decoder is now under 2% of `identify()`, so speed here has
stopped buying anything. What the strips buy is peak RSS in the stage, 111 MB to
21 MB on a 4.3 MP image, which is what matters on the memory-limited Space.
Both steps were verified by recording decoder output and detector verdict over
200 sampled `data/` images plus two synthesized carriers before and after: the
record is byte-identical, as are seven degenerate shapes (`1x65536` through
`8x8192`, plus an odd width) that clear the caller's area check.
Regression coverage:
- [`test_identify.py`](../tests/test_identify.py)
- [`test_trustmark_detector.py`](../tests/test_trustmark_detector.py)
- [`test_invisible_watermark.py`](../tests/test_invisible_watermark.py)
- [`test_invisible_watermark.py`](../tests/test_invisible_watermark.py) --
note `test_in_tree_decoder_matches_upstream` is the parity guard against
upstream's own decoder, and the whole module is `skipif(not is_available())`.
A green run without the `detect` extra installed has not checked parity at
all, so a decoder change still owes the before/after verdict record.
## Visible mark removal
@@ -1111,6 +1251,11 @@ are CUDA-only. `controlnet`, `sdxl`, `qwen` and `default` were removed rather th
kept as a CPU path, and are rejected rather than aliased onward. There is no
content-dependent automatic router.
`qwen-zimage` normally resolves global denoise from image area for unknown content.
Measured provider cohorts bypass that curve with flat operating points. The values,
measurement derivations, and corpus limits are canonical in
[`known-limitations.md`](known-limitations.md#strength-is-content-and-seed-dependent).
For serverless cold starts, `InvisibleEngine.preload(global_only=True)` loads the
mandatory global stage and YuNet while leaving the optional Z-Image and SAM face
stack lazy until a face is detected. The default `preload()` still loads every
@@ -1240,6 +1385,63 @@ orchestration, YuNet integration, SAM selection, masks, sizing helpers, and pixe
compositing are implemented for this runtime. Changing a calibrated model input
requires the same provider-oracle and identity evaluation as a model change.
#### Verified text restoration
[`_internal/text_restoration.py`](../src/remove_ai_watermarks/_internal/text_restoration.py)
implements the opt-in `vae-glyphs` stage. A versioned manifest carries manually
reviewed strings and source-space line boxes in schema 1, or verified source-space
geometry alone in schema 2, plus a SHA-256 over decoded RGB width, height, and pixels.
Validation happens before model loading. The library never treats OCR confidence as
verification, and geometry-only operators do not need to invent text or script fields.
When enabled, `QwenZImagePipeline` reconstructs the source once through its already
loaded Qwen VAE, runs the ordinary global and face stages, blends 15% of the VAE
reconstruction into that clean result, and calls the shared restoration compositor.
The compositor derives binary source and candidate silhouettes, groups nearby lines,
uses LaMa for the initial and residual-glyph erase passes, paints fresh silhouette
edges, then copies the Qwen-VAE core with a 0.5-pixel feather. The evaluation script
imports these same mask and compositing helpers so the two implementations cannot
silently drift. Silhouette crops start 12% of line height beyond each horizontal
side, then expand each side independently while a foreground component anchored
inside the detector box still reaches that boundary, up to one line height. They
extend 8% above and 25% below. The anchored-component gate covers clipped leading
flourishes, trailing punctuation, icons, and descenders without walking into
disconnected decoration or background texture.
The stage is deliberately narrower than the engine: it rejects `sdxl-zimage`, tiles,
resolution caps, humanize, unsharp, and adaptive polish. Those combinations change
geometry or final pixels after the verified layer and have no measured oracle result.
It remains opt-in because annotations are manual and provider verdicts apply only to
the exact tested output hashes, not to the mechanism in general.
A matched stage-isolation check on the 18-face Gemini portrait grid confirms the
division of responsibility. The visible-cleaned, metadata-stripped control and the
Z-Image face-only output were both SynthID-positive; Qwen global-only and the full
Qwen-then-Z-Image output were both clean. The face stage raised identity cosine from
0.589 to 0.852 and reduced face LPIPS from 0.217 to 0.050 without reintroducing a
detectable whole-image signal. Thus Z-Image is a masked fidelity repair stage here,
not the watermark-removal stage. Exact hashes, metrics, strengths, and the one-fixture,
one-seed caveat are recorded in
[`data/evaluations/fidelity/face-stage-isolation-2026-08-13.csv`](../data/evaluations/fidelity/face-stage-isolation-2026-08-13.csv).
The public Synthid-Bypass v2 graph was subsequently audited at upstream commit
`3007d035`. Its saved-output path confirms the same division: Qwen-Image-2512
Lightning plus Canny is global, and Z-Image Turbo exists only inside the masked
face detailer. The connected face path is YOLOv8-face plus SAM; the MediaPipe nodes
described by the upstream README and the 1.2-megapixel normalization node do not
reach `SaveImage`. Upstream also applies its adaptive face strength directly,
whereas this implementation multiplies it by `FACE_DENOISE_SCALE = 0.5`.
A close reproduction on the same portrait fixture kept the control positive and
made both Qwen global-only and full Qwen-then-Z-Image outputs clean. Applying the
upstream-strength face pass raised identity from 0.589 to 0.783 and reduced face
LPIPS from 0.217 to 0.083, but remained worse than this profile's 0.852 and 0.050.
The published upstream pair 12 was also independently checked positive before and
clean after, with 0.975 identity. Exact workflow provenance, hashes, metrics,
oracle outcomes, and the DiffSynth/GGUF, scheduler, detector, and seed caveats are
recorded in
[`data/evaluations/fidelity/upstream-v2-reproduction-2026-08-13.csv`](../data/evaluations/fidelity/upstream-v2-reproduction-2026-08-13.csv).
### SDXL plus Z-Image
[`_internal/sdxl_zimage_pipeline.py`](../src/remove_ai_watermarks/_internal/sdxl_zimage_pipeline.py)
+85 -1
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@@ -172,8 +172,34 @@ from remove_ai_watermarks.identify import identify
report = identify(Path("input.png"))
print(report.platform)
print(report.signals)
print(report.c2pa_validation)
```
`c2pa_validation`, when present, reports `integrity`, `signature`,
`signer_trust`, and `signer_validity` independently, plus the reader status
codes. A valid hash and signature is a high-confidence signed claim; an
unanchored or expired signer appears in `caveats` and in these fields, not as a
lower confidence, because the reader ships no trust anchors to check against and
`signer_trust` is therefore a missing input rather than a finding. A hash or
signature failure, or a revoked signing credential, does not confirm the claimed
platform or AI origin.
A consumer must read `integrity_clashes`. When a credential fails validation,
`is_ai_generated` becomes `None`, because a claim that cannot be tied to these
bytes cannot establish origin -- the manifest may have been transplanted from a
real AI image onto anything -- and the failure is reported in
`integrity_clashes` instead. That is a different question from whether an AI
watermark is physically present in the pixels, which is what
`has_invisible_target` answers, and it stays fail-safe `True` on the same file.
Reading only `is_ai_generated` turns a broken vendor manifest into silence.
`c2pa_validation["state"]` is the reader's own aggregate and is carried for
diagnostics only; no verdict is derived from it, because it collapses a
transplanted manifest and a merely expired certificate into one `Invalid`, and
its `Trusted` level depends on anchors no default installation has. Fallback parsing reports unknown validation
dimensions, while a raw marker in an unsupported or malformed container can
leave `c2pa_validation` as `None`.
Use `check_visible=False` and `check_invisible=False` for metadata-only
inspection through the compatible path-based API:
@@ -241,6 +267,11 @@ the schema 1 serializer remains available for rolling upgrades. Asking a release
an unsupported schema raises `ValueError` rather than silently returning another
shape.
Microsoft InvisMark declarations emit both the compatible generic `soft_binding`
signal and the additive `invismark` signal. Consumers should use `invismark` to route
the image through pixel removal; the generic signal also covers content fingerprints
that must not trigger regeneration.
A record carries metadata regions, not the primary coded-pixel stream: marker
segments before the JPEG scan, every PNG chunk except `IDAT`, RIFF chunks except the
coded image, the ISOBMFF provenance boxes, the container's trailer, the parsed EXIF tags the
@@ -439,7 +470,8 @@ must use the same container extension as the source.
The returned `VideoMetadataResult` records the source, output, metadata detected
before removal, and any markers remaining after the verified strip. MP4/MOV
inspection recognizes the native TC260 `AIGC` entry in
`moov.udta.meta.keys/ilst`; its removal preserves container size and encoded
`moov.udta.meta.keys/ilst` and the QuickTime-form `meta` variants Doubao's iOS
export writes; its removal preserves container size and encoded
stream bytes. MP4/MOV/M4V are copied in bounded chunks, so a large `mdat` is not
loaded into memory; publication is atomic. MKV/WebM inspection recognizes the corresponding
`Segment.Tags.Tag.SimpleTag` representation; its removal requires ffmpeg for a
@@ -604,6 +636,58 @@ engine = InvisibleEngine(pipeline="sdxl-zimage")
The `qwen-zimage` extra is required for both profiles: each runs the same
DiffSynth Z-Image face stage.
The opt-in verified-text stage uses the same `text_manifest` argument as the CLI:
```python
engine.remove_watermark(
Path("watermarked.png"),
Path("clean.png"),
text_manifest=Path("verified-lines.json"),
)
```
Install `remove-ai-watermarks[text-restoration]`. The manifest schema and safety
constraints are documented in the CLI guide. The engine verifies its decoded RGB
hash before loading the diffusion models and rejects SDXL, downscaling, and
postprocessing combinations that were not evaluated. Tiling is allowed: the VAE
donor uses the same overlapping tiles as the global pass. `InvisibleOptions` exposes the
same field for `remove_all`; after a visible-stage edit, the manifest must be built
against the staged pixels rather than the pristine source.
Use manifest schema 1 for manually reviewed text plus script metadata. Automated
operators that verify only text-region geometry should emit schema 2 lines with a
`box` and optional `angle`; no placeholder transcription or script is required.
Since 0.27.1 the mode's global 15% Qwen-VAE fidelity-anchor blend is **off by
default** (`fidelity_anchor=False`): that whole-frame blend was measured to
return detector-visible OpenAI SynthID on poster-scale manifests (official
Content Provenance API, 2026-08-19 - detected x6 with the anchor, clean x6
without it, controls and base outputs validated in the same sessions). Pass
`fidelity_anchor=True` to reproduce the 0.27.0 research behavior.
### Drafting manifest lines
`remove_ai_watermarks.text_draft` proposes lines for a manifest; it never
produces verified ones:
```python
from remove_ai_watermarks.text_draft import draft_text_lines
draft = draft_text_lines(Path("watermarked.png"))
for line in draft.accepted:
print(line.box, line.script, line.min_score, line.text)
```
Install `remove-ai-watermarks[text-draft]` (CPU, no torch: PaddleOCR detection
plus three script-chosen recognition engines). A line lands in `accepted` only
when three crop paddings normalize identically and every confidence clears
`min_score` (default 0.85); `accepted` means crop-stable, NOT ground-truth-
correct - on the reference posters the draft's exact-text precision was 90.0%
and 94.4% because high-confidence OCR still lost punctuation. Every accepted
line needs a human yes/no before a manifest may claim `verified: true`.
`source_pixel_sha256` is re-exported here for building the manifest's
pixel-binding hash against the exact source the engine will decode.
`remove_watermark` takes strength, seed, tiling, resolution, and postprocessing
controls. It takes no model id, step count or guidance scale, and neither does the
constructor: each profile pins its model stack, its per-stage schedule and CFG
+41 -1
View File
@@ -3,6 +3,21 @@
This page describes the release behavior defined in this repository. External
registry state can change independently, so verify it during a release.
## Published surfaces
A release is complete only after all four published surfaces are verified:
| Surface | Published result | Automation |
|---|---|---|
| PyPI | The `remove-ai-watermarks` wheel and source distribution | `publish.yml` |
| Homebrew | The `remove-ai-watermarks` formula in `wiltodelta/homebrew-tap` | `distribute.yml` |
| Hugging Face Space | The Space demo deployed on the new release through a requirements-pin bump in `wiltodelta/raiw-hf-space` | `raiw-hf-space` sync workflow; the pin bump is manual, `distribute.yml` only re-installs the pinned version |
| ComfyUI Registry | A compatible release of `wiltodelta/ComfyUI-remove-ai-watermarks` with its own node version | `distribute.yml` and the node repository's workflows |
The GitHub Release is the trigger and release record for this flow. Conda is
not a supported publishing surface: this repository has no conda recipe or
conda publication job.
## Release sources of truth
The package version appears in:
@@ -43,7 +58,16 @@ PyPI API token from the repository.
waits for the matching source distribution to appear on PyPI, then:
- updates the Homebrew tap formula URL and SHA-256;
- triggers a factory rebuild of the Hugging Face Space.
- triggers a factory rebuild of the Hugging Face Space: this re-installs the
version pinned in the Space repo, it does NOT upgrade the demo;
- synchronizes, tests, versions, and publishes the ComfyUI nodes.
Upgrading the Hugging Face Space is a separate, manual step: bump
`remove-ai-watermarks[visible,heif]` in `wiltodelta/raiw-hf-space` (`pyproject.toml`,
`uv lock`, and the re-exported `requirements.txt`), then push. That repository's
`sync-to-hf.yml` mirrors the files onto the Space, which rebuilds on the new
pin. Its callback smoke tests run in that repository's CI on every push; they
are the scenario check for the demo surface.
The workflow can also be started manually with an optional version input.
@@ -100,4 +124,20 @@ After publication, verify:
- the Homebrew formula points to the new source distribution;
- the distribution workflow completed successfully;
- the ComfyUI Registry node requires the new library version;
- the Hugging Face Space serves the new release: its `requirements.txt` pin
matches (raw file via the HF API), the runtime stage is `RUNNING` after the
rebuild, and one live `identify` and one live `visible` API call succeed
against the running Space;
- a clean install can run `remove-ai-watermarks --version`.
A clean-install check run immediately after publication can fail with "no
version of remove-ai-watermarks==X.Y.Z" even though the simple index already
lists it: uv serves its cached pre-release view of the index. Re-run with a
fresh cache (`UV_CACHE_DIR=$(mktemp -d)`) before treating it as a release
failure.
The ComfyUI sync run can fail the same way on its own: it resolves the version
from the PyPI JSON API (which updates first) but installs the test dependency
with pip against the simple index, whose CDN edges lag by minutes. Rerun the
failed `distribute.yml` comfyui job once the simple index lists the release;
nothing about the release itself is wrong.
+29 -5
View File
@@ -37,7 +37,7 @@ when you can select the affected area yourself.
| `veo` | Current four-point diamond and legacy `Veo` text | Fixed bottom-right corner | Uses separate silhouettes and requires a recurring match; learned fill is preferable on structured backgrounds. |
| `seedance` | Boxed `AI` label | Fixed bottom-right corner | Requires an anchored recurring match; the full localized box is filled because a thinner synthetic shape mask leaves the real translucent rim behind. |
| `dola` | `Dola AI` text | Fixed bottom-right corner | Requires an anchored recurring match; ByteDance or BytePlus provenance can relax only an existing visual run. |
| `hailuo` | `MINIMAX \| hailuo AI` composite label | Fixed lower edge | Uses a synthetic waveform, text, separator, and ring silhouette; the complete recurring label box is filled. |
| `hailuo` | `MINIMAX \| hailuo AI` composite label | Fixed lower edge | Uses a synthetic waveform, text, separator, and ring silhouette; the complete recurring label box is filled. A TC260 label naming MiniMax as producer can relax only an existing stable run. |
| `kling` | Kling swirl, `KLING AI`, version, and optional `PRO` suffix | Fixed bottom-right edge | Combines a synthetic logo rescue with font variants, an edge gate, a white-label gate, and anchored temporal recurrence. |
`video identify`, `video visible`, and `video all` share this registry and the
@@ -80,11 +80,19 @@ The inspection and stripping code handles signals in these groups:
- Samsung AI editing markers;
- Hugging Face job metadata;
- open Stable Diffusion style DWT-DCT watermarks with the `detect` extra;
- Adobe TrustMark with the `trustmark` extra.
- Adobe TrustMark Variant P schemas 0-2 with the `trustmark` extra. Variant Q
needs a different model, while schema 3 is deliberately rejected because it
produced persistent false positives on unrelated generators.
`identify` combines detected signals into a `ProvenanceReport`. It reports
unknown when evidence is absent. It never treats missing metadata as proof that
an image is human made.
an image is human made. C2PA presence alone is not a verified identity: the
report distinguishes asset binding, claim signature, signer trust, and signer
validity. High-confidence C2PA attribution requires an intact asset binding and
claim signature; signer trust and certificate expiry are reported as their own
dimensions and as caveats, since no trust anchor list ships to evaluate them.
Fallback claims, which validate nothing, remain medium-confidence, while a failed
binding or signature or a revoked credential contributes no origin verdict.
## File and container formats
@@ -143,6 +151,20 @@ of C2PA for its decision, but it is not local: the sanitized raster is uploaded
to OpenAI after explicit acknowledgement. It is intentionally excluded from
`identify` and its negative result remains inconclusive.
Microsoft Paint can name `com.microsoft.invismark.1` in a C2PA soft-binding
assertion. Inspection reports both that exact algorithm and its signed `value`,
which Paint uses as the identifier carried by the pixel watermark, and emits an
additive `invismark` signal so callers can select pixel removal without parsing
the generic `soft_binding` detail. Photos uses a parallel local writer path.
Metadata stripping removes only the embedded manifest; `invisible` and `all`
guarantee the supported InvisMark removal contract by regenerating the pixel
layer as well. The project has no validated local InvisMark decoder, so local
inspection cannot independently verify the output. Microsoft's official
[Content Provenance Detection API](https://learn.microsoft.com/en-us/azure/ai-services/content-safety/how-to/how-to-provenance-detection)
is the external oracle: it reports pixel `Watermark` and embedded `C2PA` results
separately; a control-positive, output-negative pair is the available per-file
verification path.
For MP4, MOV, and M4V, `video invisible` or the explicit
`video all --invisible` option can regenerate the video through a VAE and strip
source metadata. The shipped profile is oracle-certified, but it is not a local
@@ -162,11 +184,13 @@ not a universal clean verdict.
| --- | --- | --- | --- |
| Google Gemini | Sparkle | Diffusion regeneration | C2PA and related source signals |
| Google Veo video | Veo diamond and legacy text | Oracle-certified VAE removal for SynthID | C2PA and related source signals |
| OpenAI image generators | None registered | Official remote pixel verifier; diffusion regeneration | C2PA and generator provenance |
| OpenAI image generators | None registered | Official remote pixel verifier; diffusion regeneration for supported invisible signals | C2PA and generator provenance |
| Microsoft Paint and Photos | None registered | External Microsoft oracle for InvisMark; no validated local decoder | Paint C2PA soft-binding algorithm and identifier |
| Stable Diffusion and SDXL | None registered | Diffusion regeneration; optional open decoder | Embedded parameters and text metadata |
| FLUX | None registered | Diffusion regeneration; optional open decoder | C2PA for supported sources |
| Adobe Firefly | None registered | No proprietary local decoder | C2PA; optional TrustMark decoder |
| Adobe Firefly | None registered | Optional TrustMark Variant P decoder | C2PA |
| Midjourney | None registered | No registered pixel decoder | EXIF, XMP, and IPTC signals |
| Luma AI | None registered | No registered pixel decoder | PNG text generator tags (Uni-1) |
| ByteDance generators | Doubao and Jimeng marks | No registered pixel decoder | TC260 AIGC, supported C2PA, and exact app-export AIGC disclosures |
| Qwen | Qwen mark | No registered pixel decoder | TC260 AIGC |
| Kling | Kling image and video marks | No registered pixel decoder | TC260 AIGC |
+5 -5
View File
@@ -891,8 +891,8 @@ study (section 2.2) gives empirical floors:
> were removed, and `OPENAI_STRENGTH` / `GEMINI_STRENGTH` / `UNKNOWN_STRENGTH` went
> with them. Everything from here to the end of this section is a record of what was
> measured on those profiles, kept because the oracle verdicts are still the evidence
> base. For the strength policy in force now see `module-internals.md`: `qwen-zimage`
> uses `resolution_adaptive_denoise`, `sdxl-zimage` a flat vendor ladder.
> base. For the strength policy in force now see
> [`known-limitations.md`](known-limitations.md#strength-is-content-and-seed-dependent).
The default was **vendor-adaptive** (`watermark_profiles.resolve_strength` +
`vendor_for_strength`): the tool read the C2PA issuer on the original input and picked
@@ -1048,9 +1048,9 @@ solid at 0.10 but at 0.15 it is near-threshold noise; (2) for reliable removal p
a strength with MARGIN above the borderline (controlnet >= 0.20), not exactly on
it; (3) **historical engineering conclusion:** this dated run argued for a
higher ControlNet strength than the then-current default. That proposal was
later superseded. The current resolver intentionally shares the 0.10/0.15
ladder between SDXL and ControlNet and uses a separate Qwen ladder; see
`_internal/watermark_profiles.py`.
later superseded. The resolver of that period shared the 0.10/0.15 ladder between
SDXL and ControlNet; the current policies are recorded in
[`known-limitations.md`](known-limitations.md#strength-is-content-and-seed-dependent).
Source images are private (faces / product shots), not committed; reproduce on any
photoreal + flat-graphic gpt-image pair, varying the seed, and re-checking the
oracle.
+228 -2
View File
@@ -20,8 +20,8 @@ filter applied to every candidate below.
## Problem recap
The `invisible` pipeline is SDXL base 1.0 img2img to defeat SynthID. The default
strength has risen over time as Google hardens SynthID (0.05 -> 0.10 -> **~0.30**, the
current threshold for fresh Gemini output); higher strength deforms text more, which is
strength rose over time as Google hardened SynthID (0.05 -> 0.10 -> **~0.30** in
this experiment; the later measured operating point is 0.27); higher strength deforms text more, which is
exactly why text protection matters. Text is protected via Differential Diffusion with a
per-pixel change map (`preserve` ~0.9) driven by the PP-OCRv3 DB detector
(`text_protector.py`). Large text survives; **small text (sub ~8 px strokes) softens or
@@ -143,3 +143,229 @@ Deep-research workflow run `wf_118b9a03-3eb` (2026-05-29). Findings adversariall
(2/3 refutes required to kill a claim). This note records research only; no code change is
implied until a prototype validates fidelity and the SynthID-scrub guarantee on the
restored output.
## 2026-08-13 OCR plus LaMa prototype
A lightweight version of the recommended two-stage architecture was tested on
the three tracked text fixtures. It used the already-clean Qwen result as the
base, recognized the source text, removed source and Qwen glyph contours with
LaMa, and rendered the recognized strings as fresh pixels. No source pixels
were pasted back.
The result validates only part of the hypothesis. Character-weighted CER on the
two multilingual posters fell from 0.338/0.305 to 0.007/0.007, and OpenAI Verify
remained clean for both matched Qwen and restored pairs. However, replacement
fonts changed the design, whole-image LPIPS worsened by 0.067 on each poster,
and the light poster retained a shadow in one small English line. On the Chinese
sign, punctuation errors moved CER from 0.074 to 0.111. The Google verifier run
was inconclusive because the available account detected both the restored image
and the byte-identical Qwen control that a previous account had called clean.
The experiment supports a proper glyph-conditioned restorer, not shipping the
plain OCR/system-font compositor. Exact hashes, metrics, masks, and provider
verdicts are tracked in
[`data/evaluations/fidelity/text-restoration-2026-08-13.csv`](../data/evaluations/fidelity/text-restoration-2026-08-13.csv).
## 2026-08-13 AnyText2 follow-up
The official AnyText2 SD1.5 checkpoint was then tested as the glyph-conditioned
restorer. Its ModelScope entry and code are Apache 2.0, and the downloaded
checkpoint matched the published SHA-256. An official blackboard edit completed
successfully before the fixture run, establishing that the runtime reproduced
the model rather than silently exercising a fallback.
On the Chinese sign, a three-line local edit over the exact Qwen output scored
CER 0.185 under the standard detector. Font mimic from the source glyph masks
scored 0.222. Whole-image LPIPS changed from 0.289 to 0.338 and 0.345 respectively.
A padded crop-recognition check showed why the comparison matters: Qwen contained
the full correct text and scored 0.000, while default AnyText2 still scored 0.074
with two substituted characters and mimic remained at 0.222. The provider oracle
was deliberately not called because these variants had already failed the
content-fidelity gate.
AnyText2 is therefore not the missing production restorer in its published form.
The negative result is narrower than the model family: only the SD1.5 checkpoint
is public, while AnyText2XL remains listed as future work. The current wrapper
also truncates each quoted text line to 20 characters, which prevents a direct
test of several tracked English and Russian poster lines. Exact model provenance,
output hashes, and metrics are recorded in
[`data/evaluations/fidelity/anytext2-restoration-2026-08-13.csv`](../data/evaluations/fidelity/anytext2-restoration-2026-08-13.csv).
The same cross-check exposes a measurement bug in the earlier lightweight
restoration result. Paddle detection made tight boxes that omitted the final
Chinese full stop from two lines, producing Qwen CER 0.074 although the pixels
and padded recognition were correct. Adding 16-32 pixels of horizontal context
restored every punctuation mark. A deterministic rerender using the full OCR
strings and the closest of nine mask-scored CJK fonts also reached detector CER
0.000, but its heavier Hiragino Sans GB W6 glyphs raised LPIPS from 0.289 to 0.327.
The actionable design is selective restoration: compare padded source and output
recognition first, and preserve the Qwen output when they already match.
That policy was tested on the two multilingual posters. A manual prototype kept
the lines whose padded source and Qwen recognition agreed and rerendered only the
changed lines. The edited mask fell from 15.4%/17.0% in the full compositor to
5.5%/5.5%. On a single Paddle `en+ru+ch` route, CER changed from 0.378/0.413 for
Qwen to 0.101/0.112, while LPIPS was only 0.120/0.103 rather than the full
compositor's 0.174/0.162. The different OCR route is intentional and all three
variants were remeasured through it; these CER values are not directly
comparable with the earlier Vision/Paddle hybrid results.
Both selective outputs returned `No OpenAI signals detected` in OpenAI Verify,
and the original light poster returned `Generated with OpenAI tools` immediately
afterward as the positive control. The dark poster was visually clean. The light
poster still showed one local old-text shadow, so mask construction remains the
blocking defect. Exact hashes, metrics, mask fractions, and oracle controls are
in
[`data/evaluations/fidelity/selective-text-restoration-2026-08-13.csv`](../data/evaluations/fidelity/selective-text-restoration-2026-08-13.csv).
Uniformly expanding every selected glyph mask by two pixels removed that light
poster shadow and moved CER from 0.101 to 0.081 without a meaningful LPIPS cost.
It also expanded the edited area from 5.5% to 7.0%, and the identical rule made
the dark poster worse at CER 0.147 rather than 0.112. Those follow-up bytes have
not been oracle-checked. The next prototype should detect residual source glyphs
per line and expand only the failing component, rather than introducing another
poster-wide tuning constant.
The manual selection was then replaced with per-line padded recognition. A line
is left untouched only when the source recognizer is sufficiently consistent
with the verified line and normalized source/candidate recognition agree
exactly. The automatic rule reproduced the manual selection on the dark poster
and correctly kept one additional large Russian line on the light poster. It
reduced that poster's effective edited area from 5.5% to 4.1%.
Mask cleanup became a measured second pass rather than a global dilation. After
the first LaMa erase, the prototype finds contrast that remains specifically at
the original glyph positions, dilates only that residual, and erases it before
fresh text is drawn. This removed the visible double glyphs from both posters.
The automatic outputs scored LPIPS 0.113/0.104 and detector CER 0.123/0.119, with
effective edited fractions of 4.1%/5.7%. The light aggregate CER is pessimistic:
the page detector fragments its untouched Cyrillic line into Latin-like pieces,
while the padded Russian recognizer returns the exact expected text.
OpenAI Verify returned `No OpenAI signals detected` for both new hashes and then
`Generated with OpenAI tools` for the original light poster in the same browser
sequence. Reproducing the prototype from the tracked script exposed harmless
ONNX rounding on the light image: 386 pixels differed by at most one channel
value from the initially checked hash. The exact tracked output hash
`900def5a...` was therefore submitted separately, returned clean, and was
followed immediately by another positive source result. The dark tracked output
was byte-identical to the initially checked hash.
The Chinese sign provides a no-edit control for the selector. Detector boxes for
its three large lines overlap vertically, so Latin-style vertical padding
incorrectly mixed neighboring lines. Horizontal-only CJK padding captured the
terminal punctuation without mixing neighbors and made source and candidate
recognition agree exactly on all three lines.
The script then produced a zero mask and copied the Qwen candidate byte for byte.
This prevents the heavier-font regression seen in the earlier CJK compositor,
but does not resolve the unavailable Google-negative oracle control.
The result clears the measured OpenAI gate without a manual line selection, but
is not a production design yet. It still assumes verified source strings and
line boxes, relies on macOS system fonts, and needs evaluation on uncurated
layouts, rotated text, false OCR matches, automatic line-box discovery, and a
reproducible Google-negative control.
The later source-silhouette experiment removed the font lookup but did not meet
the actual visual requirement. Native-size review found changed stroke weight,
color variation, edge antialiasing, and decorative details even where crop OCR
was exact. A narrower `vae-glyphs` experiment uses the silhouette only as a
support mask: exact pixels come from a Qwen-VAE reconstruction, while a fresh
flat-color silhouette supplies only the outer edge beneath that core. Across 48
typography cases (548 annotated lines), this improved glyph-edge MAE in 48/48
and text-box SSIM in 47/48. The median values moved from 37.59 to 32.42 and from
0.854 to 0.914 respectively. One separate untracked core-only output with a
1.43% donor area returned `No OpenAI signals detected`; the tracked script then
reproduced those exact bytes. A 0.5-pixel feathered sibling with 2.75% nonzero
donor area improved mean text-box SSIM from 0.957 to 0.960, with a 0.918 minimum
across 15 verified lines, while full-image RGB SSIM reached 0.864. Crop OCR
recovered from 7/15 exact lines on the raw pass to 14/15, equal to the source's
own recognizer floor. Whole-image LPIPS was 0.082, but only 0.108% of pixels
remained exactly equal to the source and the detected face's Laplacian-variance
ratio was 0.670, confirming residual global smoothing. A same-session
OpenAI Verify sequence detected the exact source control in 1/1 check, returned
clean for the raw global pass and clean-fidelity anchor in 1/1 each, and returned
clean for the feathered output in 3/3 repeats. The tracked script reproduced
that feathered file byte for byte. This proves two materially better exact-output
Pareto points, not a general operating range. The 48 matrix outputs and other
mask sizes remain oracle-unverified.
The first Google oracle sample did not transfer. For the synthetic CJK sign,
two separate work accounts detected SynthID in both the resaved positive source
control and the exact Qwen-VAE donor candidate. The candidate's text-box SSIM
improved from 0.791 to 0.835 and its glyph-edge MAE from 35.48 to 22.49, but its
3.67% donor layer did not create a clean operating point. The Qwen silhouette
base was already detected, as was the earlier original-sign Qwen baseline in the
same account. The measured cause is therefore insufficient global Google
regeneration, not a demonstrated watermark regression from the text donor.
Google needs a stronger oracle-clean global anchor before the narrow donor can
be evaluated there.
A targeted follow-up supplied that missing anchor for one CJK case. An explicit
Qwen global pass at strength 0.30 returned no reliable SynthID signal in Gemini,
while the matched source control was detected. Applying the 0.5-pixel
`vae-glyphs` layer to that clean anchor changed 1.17% of the image and raised
mean text-box SSIM from 0.765 to 0.964 (minimum 0.963), with mean text-box MAE
falling from 20.74 to 5.38. The post-donor output then returned clean in 3/3
Gemini checks across two work accounts. A separate 18-face fixture with four
tiny UI-text lines also had a clean strength-0.30 anchor; its donor layer changed
0.70% of the image, raised mean text-box SSIM from 0.617 to 0.976 (minimum
0.972), and returned clean in 3/3 checks across the same two accounts. One
quota-exceeded response is excluded from both pass rates. These are two exact
oracle-certified outputs, not a general operating range: other layouts, masks,
strengths, seeds, and donor areas remain unverified.
An automatic-box follow-up merged Paddle word detections by vertical overlap.
It found exactly 20/20 poster lines and 3/3 sign lines, with mean IoU 0.857,
0.847, and 1.000 against the verified boxes. That structural match was not
sufficient: reusing the annotation crop padding changed recognition decisions,
reduced preserved dark-poster lines from 7 to 4, and expanded its edited
fraction from 5.7% to 11.2%.
A recognition-only sweep isolated the crop sensitivity. Limiting vertical
padding around detector boxes to 8-12% of line height reproduced the verified-
box decision vectors on both posters; 10% was used for a full follow-up. It kept
8/20 and 7/20 lines with edited fractions of 4.1% and 5.7%, and visual inspection
found no double glyphs. Whole-image LPIPS remained 0.113/0.104, but detector CER
was 0.127/0.154 instead of 0.123/0.119. The dark regression failed the fidelity
gate, so these hashes were not submitted to the provider oracle. The opt-in flag
remains only to reproduce the negative result. Count, IoU, and matching decision
vectors are therefore insufficient gates for automatic boxes; the next design
needs box rectification or recognition stability under crop jitter before it
can replace verified geometry.
Removing verified strings was tested separately with an annotation-seed dry
run. It detects boxes, chooses `en`, `ru`, or `ch` from Unicode script, and
accepts a draft only when three crop paddings normalize identically and every
confidence is at least 0.85. One execution proposed 20 and 18 poster lines, but
exact-text precision against the held-out annotations was only 90.0% and 94.4%.
The stable errors were punctuation: one lost English comma and an ideographic
comma consistently replaced by ASCII. Thus crop agreement and confidence do
not verify literal text. The helper is retained only to seed annotations; every
proposal needs manual review before it can enter the restoration compositor.
## Production-path anchor leak and fix (2026-08-19)
The engine `text_manifest=` path (unlike the research compositor above) blends a
15% Qwen-VAE fidelity anchor across the WHOLE frame before glyph restoration.
Certified through the official OpenAI Content Provenance API on the exact
production path (qwen-zimage, seed 0, no strength override, untiled, LANCZOS
resize-back, metadata strip; library 0.27.0 @ 50d9f448):
- controls (pixel-identical metadata-stripped sources): `synthid: detected` -
the pixel channel was proven live before every session;
- base outputs: `clean` x6 (two 20-line posters, 3 attempts each);
- text-restored WITH the anchor: `synthid: detected` x6, deterministic;
- text-restored with `FIDELITY_BLEND_ALPHA = 0` (runtime ablation, base bytes
identical between runs): `clean` x6.
The anchor was therefore the leak channel: a 15% global donor admixture over a
scrubbed frame returns enough OpenAI SynthID for the provider detector. Fidelity
cost of dropping it (source-referenced text-box MAE): 11.60->11.72, 7.79->7.86,
and 7.57->8.13 across the two posters and the CJK sign - well under one point
against base MAEs of 24.7/16.8/10.2. Since 0.27.1 the anchor is off by default
(`fidelity_anchor` parameter on `remove_watermark` / `InvisibleOptions` /
`--fidelity-anchor`); Google rows were not re-queried because the default
strength leaves that fixture's base detected (the vendor-strength lane tracks
that separately). Certification artifacts: raiw-app
`data/certification/text-restoration-2026-08-19-A1/` (sha256-stamped rows).
+18 -5
View File
@@ -39,6 +39,15 @@ confidence), reviewed once, then re-baselined. Lost detections are the alarm.
Implemented as `scripts/sidecar_regression.py` (resumable, ~1.5 h at 8 workers).
A 2026-08-15 metadata-only C2PA regression audit over the local historical
corpus caught two structured-parser gaps before release: an exact Firefly claim
generator without a repeated source type, and a Dreamina generator carried by a
reachable ingredient under a generic update manifest. Both now have focused
tests. The same audit confirmed that invalid hash/signature claims lose origin
attribution without losing the C2PA inventory, and exposed the absence of
production trust anchors in the SDK defaults. Dataset-derived counts and
identifiers remain in the gitignored audit output.
#### Local run protocol
Re-run `identify` against locally recorded sidecars, classify losses separately from intended new detections, and keep generated reports under `.local-eval/`. Do not commit dataset-derived counts or identifiers.
@@ -177,11 +186,14 @@ report recall from the detector-sampled set.
## Tier D -- external oracles
SynthID removal cannot currently be verified locally because no public decoder weights
exist. Each vendor has its own oracle and it covers only that vendor's content. OpenAI
documents a synchronous Content Provenance API with a distinct SynthID result, while the
Gemini app provides a manual, quota-limited Google verifier. A quiet metadata proxy is
**not** proof the pixel watermark is gone.
Proprietary watermark removal cannot be verified locally by design -- no public decoder
exists. Each vendor has its own oracle and it covers only that vendor's content:
`openai.com/verify` for OpenAI, the Gemini app for Google, and Microsoft's
[Content Provenance Detection API](https://learn.microsoft.com/en-us/azure/ai-services/content-safety/how-to/how-to-provenance-detection)
for InvisMark. The Microsoft API reports `Watermark` and `C2PA` separately. It therefore
needs a pixel-identical metadata-stripped control: the control must lose `C2PA` while
remaining `Watermark`-positive before a candidate's negative result can be attributed to
pixel regeneration. A quiet metadata proxy is **not** proof the pixel watermark is gone.
OpenAI's API documentation says not to use repeated queries to reverse-engineer, remove,
or evade a watermark. Using it as an adaptive research oracle therefore requires explicit
@@ -189,6 +201,7 @@ authorization. Without that authorization it must not become a training loss, se
or automated removal gate. The provider-specific detector and pixel-only removal research
protocol is in [`synthid-detector-removal-plan.md`](synthid-detector-removal-plan.md).
Scope honestly: this tier certifies strength floors on a handful of images per vendor, and
that is all it can do. See `docs/synthid.md`.
+114
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@@ -171,6 +171,120 @@ Three readings, all MEASURED, none of them about SynthID:
so the `max(temporal_baseline, 1e-6)` denominator collapses and the ratio
inflates. This is the predicted defect, now observed rather than argued.
## Measurements on the real carrier (2026-08-06)
The public Veo 3 off-road sample was downloaded and its sha256 matched the manifest
exactly, so everything below is measured on the same file the 2026-07-31
calibration used. Its properties, none of which the manifest recorded at the time:
H.264 1920x1080 at 24 fps, 8.000 s, 5,155,063 bps video, plus an **AAC 48 kHz
stereo 192,241 bps audio track of 7.914 s**.
The shipped profile therefore delivers 512x288 at 12 fps: **7.1% of the frame area
and 3.6% of the pixels per second.**
### The geometry prize, measured end to end
Scored with `scripts/video_fidelity_probe.py` against the untouched 1920x1080
source, all at `noise_std=0.15`:
| Geometry | Frame area | PSNR | SSIM | Temporal | Bitrate |
| --- | --- | --- | --- | --- | --- |
| 512x288 @12 (shipped) | 7.1% | 25.3971 | 0.8215 | 1.0407 | 2187 kbps |
| 768x432 @12 | 16.0% | 27.3796 | 0.8556 | 1.0323 | 3782 kbps |
| 1024x576 @12 | 28.4% | 28.8542 | 0.8819 | 1.0262 | 5604 kbps |
| 512x288 @24 | 7.1% | 25.6142 | 0.8270 | 1.0995 | 3181 kbps |
**512 to 1024 is worth +3.46 dB, against 1.92 dB for the entire `noise_std` axis.**
The geometry lever is roughly twice the noise lever, which is the first hard number
this investigation has for the size of the prize. What it still costs in removal is
unknown: none of these was ever submitted.
Two readings that are not obvious from the table:
- **Temporal residual improves as resolution rises** (1.0407 to 1.0262). The shared
noise field lives on the latent grid, so at 1920 it is four times finer relative
to the frame than at 512, where it stretches into low-frequency blotches. Higher
resolution plausibly makes the perturbation *less* visible, not more.
- **The frame-rate arm looks bad here and the metric is the wrong judge.** 24 fps
buys +0.22 dB and worsens the temporal ratio to 1.0995, but what 24 fps actually
buys is smoothness, which neither PSNR nor SSIM measures at all. The metric sees
only the cost. Do not decide the fps question from this table.
Encoder cost on an M-series MPS device, 8 seconds of source: 51 s at 512/12, 180 s
at 768/12, 380 s at 1024/12, 190 s at 512/24. Native 1920x1080 at 24 fps
extrapolates to roughly 46 minutes for the same 8 seconds, around 350x real time. A
native run was started and killed before producing anything, so that figure remains
an extrapolation.
### The certified row does not reproduce
Re-running the certified configuration (512/12/0.15, seed 0) on this machine gave
25.5002 dB and 1.0675 against the manifest's 25.3911 and 1.0578, and a different
output sha256. The manifest records neither device nor dtype, and the original was
almost certainly CUDA fp16 while this was MPS fp32. **The oracle certified a
specific file that cannot be rebuilt**, so any re-run produces an artifact the
verifier never saw. Device and dtype belong in the schema.
### Audio passes through untouched, and the output still reads clean
Established on two carriers, by comparing the extracted audio bitstream sha256 of
input and output:
- Veo carrier: `674063df...` in, `674063df...` out.
- A Lyria 3 track generated for this purpose: `6ee4c041...` in, `6ee4c041...` out.
The Lyria case is the sharper one because its provenance is known. Google's own
generator stamps it: `get_ai_metadata` reads a C2PA manifest naming
`Google C2PA Core Generator Library`, issuer `Google LLC`, `trainedAlgorithmicMedia`.
After the shipped path runs, that output reports `{}` -- every metadata marker
stripped, `remaining_metadata` empty, visuals regenerated -- while the audio the
generator produced is bit-for-bit intact.
So the pipeline can produce a file that **our own detector calls clean while an
untouched Google-generated audio track sits inside it**. The mechanism is proven;
whether that audio carries an audible-to-the-verifier SynthID mark is not, and only
the oracle can say. If it does, this is a shipped defect rather than a quality
question, and it outranks everything else in this document.
Worth recording alongside it: the Veo carrier itself returns `{}` from
`get_ai_metadata`. The public sample carries no C2PA at all, which is exactly why it
needed an oracle verdict in the first place.
## State when this work was parked (2026-08-06)
Landed in `main` through PR #78: the manifest-backed default pin, the
scaling-factor gate and its single seam, the sweep loading through the engine's
loader, `scripts/video_fidelity_probe.py` with its tests, the extended manifest
schema, and this document. **The shipped operating point did not move**: it is
still 512 px / 12 fps / `noise_std=0.15`.
A product requirement arrived late and reframes the target: output resolution,
frame rate and bitrate must not be reduced. Resolution, frame rate and crf are
parameters and can be preserved, but zero quality loss is not achievable by this
mechanism at all -- removal works by rebuilding pixels, so a regeneration can never
return its input. The honest goal is to preserve container properties and make the
perceptual loss imperceptible, judged by DISTS and VMAF rather than PSNR. Two
consequences follow: crf 18 on this path against crf 14 on the visible path is an
unexplained asymmetry and a free quality win, and the oracle's 100 MB limit means a
higher-quality profile is *harder* to certify than the one it replaces.
Nothing is blocked on analysis. Six oracle submissions were prepared and never run,
because file upload to the verifier failed at the tool level:
1. A Lyria carrier and the pipeline's output from it, answering the audio question.
2. A multiplexed control-plus-candidate file at the shipped geometry, validating
whether the verifier reads a concatenated pair by time range. Verified locally
frame by frame: half one is bit-identical to the control, half two to the
candidate.
3. Three more multiplexed pairs for 768, 1024 and 24 fps, worth three queries
instead of six if the instrument validates.
Every generated artifact for those submissions has since been lost with its
scratch directory, which is the intended lifecycle for generated media. Rebuilding
costs one download and roughly 25 minutes of encoding; the Lyria track is the
exception, since regenerating it would produce a different track, and the copies
that survive are the only ones.
## The single most important unknown
**How much the 512 px downscale contributes to removal.** Every quality gain routes
+6 -9
View File
@@ -10,7 +10,7 @@ Who embeds what, and whether it is locally detectable (so we know which gaps are
**Root cause and external confirmation (deep-research 2026-06-19, adversarially verified).** This is the SCHEME's ceiling, not our usage — there is no better decoder to adopt. The imwatermark maintainers state verbatim (both the ShieldMnt and Stability-AI READMEs) that the algorithm "cannot guarantee to decode the original watermarks 100% accurately even though we don't apply any attack." Independent measurement (WMAdapter, arXiv:2406.08337 Table 2) puts dwtDct at only **~0.79 bit accuracy on CLEAN images (~38/48 bits — already below our 44 gate)**, collapsing to ~0.50 (chance) under crop/JPEG. Two code-verified + locally-reproduced mechanisms drive the content-dependent failures: (1) the decoder reads each bit as the **highest-magnitude DCT coefficient per block**, so any content coefficient exceeding the encoded target flips the bit; (2) the default embed is in the **YUV chroma channel, which 8-bit-clamps on white/bright pixels** (a +36 chroma delta survives a white-fill round-trip as only +4, ~89% loss) — this is the mechanism behind the bright-flat / minimalist failures and the all-ones degenerate decode. No maintained fork or detector decodes this scheme reliably: the WAVES benchmark (arXiv:2401.08573) relegates DWT-DCT to supplementary appendix G.5 and targets Stable Signature / Tree-Ring / StegaStamp instead; learned encoder/decoder schemes reach ~0.98-0.99 clean but are a DIFFERENT watermark class (not what SDXL/FLUX stamp). `dwtDctSvd` does not help (SDXL embeds `dwtDct`; dwtDctSvd cannot decode it, and its clean accuracy ~0.72 is lower). **Authoritative conclusion: the open DWT-DCT mark cannot be turned from positive-only into a reliable real-world detector; keep it positive-only and rely on C2PA.** (Refuted along the way: that the library is unmaintained, and that it is robust to JPEG but only fails on geometric attacks — both did not survive verification.)
Consequence for the FLUX hosted-output question (BFL Playground, FLUX.2 [pro] + FLUX.1 [dev], 2026-06-19): all samples carry the signed C2PA manifest (issuer "Black Forest Labs"); the open DWT-DCT decode returned `None`, but every available FLUX carrier (textured fox AND a minimalist-flat generation) failed the positive control (28/48), so the detector is blind on them and **whether BFL hosted output embeds the open pixel watermark is UNRESOLVED** (an earlier note here wrongly asserted it absent — overstated; a later note blamed "high texture" — also wrong, flat carriers fail too). What IS established: C2PA is the reliable FLUX identifier; the `_BITS_48` pattern is correct (round-trips on chatgpt/firefly/random). Resolving the hosted question needs a hosted FLUX carrier that first passes a >=44/48 positive control, which neither a textured nor a flat prompt produced — low priority (the open mark is only a stripped-metadata fallback).
- **C2PA / IPTC (covered by the issuer/marker scan):** OpenAI, Google, Adobe Firefly, Microsoft (Designer + **Bing Image Creator** collected 2026-05-24; Bing now runs Microsoft's own **MAI-Image** model, signs C2PA as "Microsoft", NOT OpenAI/DALL-E), **Stability AI** (collected from Brand Studio / DreamStudio successor; signs C2PA as "Stability AI Ltd", no SynthID, no imwatermark on its current Stable Image model — issuer added to `C2PA_ISSUERS`), and **Canva** (Magic Media signs C2PA as "Canva" + `trainedAlgorithmicMedia` with a generic `c2pa-rs` claim generator, no SynthID — issuer `b"Canva"` → "Canva (Magic Media)"; verified samples disproved the earlier assumption that Canva downloads always strip C2PA). Still unsampled: Getty, Shutterstock. Midjourney embeds NO C2PA and no invisible watermark (our `mj-*` sample carried only the IPTC tag).
- **C2PA / IPTC (covered by the issuer/marker scan):** OpenAI, Google, Adobe Firefly, Microsoft (Copilot + Designer; Bing Image Creator collected 2026-05-24 still signs as "Microsoft" and now runs **MAI-Image**, NOT OpenAI/DALL-E), **Stability AI** (collected from Brand Studio / DreamStudio successor; signs C2PA as "Stability AI Ltd", no SynthID, no imwatermark on its current Stable Image model — issuer added to `C2PA_ISSUERS`), and **Canva** (Magic Media signs C2PA as "Canva" + `trainedAlgorithmicMedia` with a generic `c2pa-rs` claim generator, no SynthID — issuer `b"Canva"` → "Canva (Magic Media)"; verified samples disproved the earlier assumption that Canva downloads always strip C2PA). Still unsampled: Getty, Shutterstock. Midjourney embeds NO C2PA and no invisible watermark (our `mj-*` sample carried only the IPTC tag).
**Samsung Galaxy AI** signs supported edits with C2PA and may carry the
proprietary `genAIType` marker. The registered visible detector covers the
@@ -28,7 +28,7 @@ take precedence over issuer attribution. Supported mappings include Higgsfield
AI, Topaz Labs Image API, and TikTok Ad Creative Toolbox; an unknown claim
generator still falls back to the certificate issuer.
**ByteDance Volcano Engine (Volcengine)** — the cloud behind Doubao / Jimeng — signs its AI image output with a cert from `certificate_center@volcengine.com` + `trainedAlgorithmicMedia` (issuer `b"volcengine"` → "ByteDance (Volcano Engine)", platform "ByteDance (Doubao / Jimeng / Volcano Engine)"); note this is the C2PA-signed surface, distinct from the XMP/PNG TC260 `AIGC` label Doubao also uses. ByteDance's **international brand (BytePlus / Seedream / Seededit)** signs the same content as **"Byteplus Pte. Ltd."**. The bare `volcengine` needle missed it, so BytePlus output was mis-attributed to "Adobe Firefly" through an incidental "Adobe XMP" toolkit string. Issuer `b"Byteplus"` now maps directly to "BytePlus (ByteDance)". ByteDance's consumer app **Dreamina** (the international Jimeng brand) signs as **"Bytedance Pte. Ltd."** with a `Dreamina/x.y` claim generator but, unlike the Volcano Engine surface, ships **no `trainedAlgorithmicMedia`**. Issuer `b"Dreamina"` maps to "ByteDance (Dreamina)" with **`asserts_ai=True`**. Registering the broader **issuer** `b"Bytedance Pte"` was deliberately avoided because that same entity also signs non-AI CapCut edits; keying on the `Dreamina` generator token is precise.
**ByteDance Volcano Engine (Volcengine)** — the cloud behind Doubao / Jimeng — signs its AI image output with a cert from `certificate_center@volcengine.com` + `trainedAlgorithmicMedia` (issuer `b"volcengine"` → "ByteDance (Volcano Engine)", platform "ByteDance (Doubao / Jimeng / Dreamina / Volcano Engine)"); note this is the C2PA-signed surface, distinct from the XMP/PNG TC260 `AIGC` label Doubao also uses. ByteDance's **international brand (BytePlus / Seedream / Seededit)** signs the same content as **"Byteplus Pte. Ltd."**. The bare `volcengine` needle missed it, so BytePlus output was mis-attributed to "Adobe Firefly" through an incidental "Adobe XMP" toolkit string. Issuer `b"Byteplus"` now maps directly to "BytePlus (ByteDance)". ByteDance's consumer app **Dreamina** (the international Jimeng brand) signs as **"Bytedance Pte. Ltd."** with a `Dreamina/x.y` claim generator but, unlike the Volcano Engine surface, ships **no `trainedAlgorithmicMedia`**. Issuer `b"Dreamina"` maps to "ByteDance (Dreamina)" with **`asserts_ai=True`**. Registering the broader **issuer** `b"Bytedance Pte"` was deliberately avoided because that same entity also signs non-AI CapCut edits; keying on the `Dreamina` generator token is precise.
- **EXIF/XMP/PNG-text generator tag (caught by `exif_generator`):** **Ideogram** writes EXIF `Make="Ideogram AI"` (collected 2026-05-24 — no C2PA, no SynthID, no imwatermark; the Make tag is the only signal). Additional verified generator stamps include **NovelAI** (`Software`, `Source`, and `Title` PNG text chunks), **Reve** (`Software` or XMP `CreatorTool` = `reve.com`), and **Aphrodite AI** (`Make` or `Software` = `Aphrodite AI`).
- **App-export provenance and AIGC JSON:** supported ByteDance-family exports can place a JSON object in EXIF `ImageDescription` or `UserComment`, independently of C2PA or TC260. Exact `product` values for Doubao, Xinghui, and Dreamina are removable product provenance, but do not alone prove that the pixels were generated. Dreamina additionally requires `exportType=generation` for that verdict. A nested Aweme `aigc_type=1` or private ByteDance `aigc_label_type=1` / `2` is an AIGC disclosure; `0` is inconclusive and can occur on a Dreamina generation export. Plain Aweme, retouch, and `lv` exports are preserved. The lower-case private field is deliberately not interpreted as the normative TC260 `Label`, whose values `1` / `2` / `3` mean generated / possibly generated / suspected generated under [GB 45438-2025](https://www.tc260.org.cn/upload/2025-03-15/1742009439794081593.pdf).
- **xAI / Grok — its own EXIF signature scheme, NOT C2PA (DETECTED by `metadata.xai_signature`, built 2026-05-26).**
@@ -45,7 +45,7 @@ pair. On the ISOBMFF path, `blank_ai_exif_tokens` provides the corresponding
in-place scrub for supported EXIF values, TC260 AIGC blocks, and the xAI pair.
- **China TC260 AIGC label (caught by `AIGC_MARKERS` / `metadata.aigc_label`, surfaced by `identify` as the `aigc` signal):** China-served generators embed an XMP `<TC260:AIGC>{"Label":"1","ContentProducer":...}` block — China's mandatory AI-content labeling (TC260 namespace `tc260.org.cn/ns/AIGC`). The label says only "this is AI", but its `ContentProducer` names the signing entity — `001` + `1` + an 18-char Unified Social Credit Code + a 5-digit product suffix, normalized by `metadata.uscc_of`, or for a few generators a bare product name. `KnownMark.tc260_producer_codes` maps the codes settled per vendor by `scripts/vendor_cohort_harvest.py` to registry mark keys, so an AIGC image relaxes the detector of the vendor it actually carries rather than a guessed pair; an unmapped or absent producer falls back to ByteDance's two products. A code identifies a legal entity, not necessarily one brand, so a hosting or aggregating platform that signs for several apps is a recall bet rather than a proof.
**Doubao** (ByteDance) uses it (verified on a public issue sample; `ContentProducer` `001191110102MACQD9K64010000`, no C2PA/SynthID/imwatermark — the XMP block is the only signal; GitHub attachment upload did NOT strip it). The same standard is mandatory for Jimeng/Kling/Qwen/Ernie etc., so the one marker covers the whole China-AIGC-labeled ecosystem. `aigc_label` reads **four image serializations** through a shared `_parse` helper: the HTML-entity-encoded XMP `TC260:AIGC` block in **either RDF form** — the nested element `<TC260:AIGC>{...}</TC260:AIGC>` (Doubao) or the attribute `TC260:AIGC="{...}"` (**PicWish**, `ContentProducer="picwish"`, verified on compatible samples) — via a container-agnostic raw-byte scan (any JSON object accepted), a raw-JSON PNG `AIGC` tEXt chunk (Doubao also writes the label this way, no namespaced marker at all — confirmed on compatible samples, `ContentProducer="doubao"`), a bare raw-JSON `{"AIGC":{...}}` object embedded in **JPEG EXIF (UserComment)** by some China-served generators, brace-matched from the scan head with `json.JSONDecoder().raw_decode` (no namespaced marker, no PNG chunk — confirmed on compatible samples, `ContentProducer="001191440300708461136T1308L"`), **and** a bare `AIGC{...}` blob (the label glued straight to its JSON, no `"AIGC":` key wrapper) embedded in a **JPEG APP segment near the JFIF header** — confirmed on compatible samples. The two raw-JSON forms are scanned in one loop (`'"AIGC"'` then `AIGC{`) that **falls through on a non-TC260 / undecodable hit instead of returning** — a quoted `"AIGC"` can appear later in an XMP packet while the real label is a bare `AIGC{...}` earlier in the file, so an unconditional early return on the quoted form would shadow the bare form (the exact bug behind the 06-10 misses). Native MP4/MOV is a fifth serialization: TC260-PG-20257A stores an `AIGC` key in `moov.udta.meta.keys` and the raw JSON in the matching `ilst` item. The seeking parser reaches a tail `moov` without reading `mdat`; removal replaces the key with `free` and blanks the validated value at the same length so every box size and stream offset stays fixed. All generic forms are gated on at least one TC260 field (`TC260_AIGC_FIELDS`) so a generic `AIGC` key cannot false-positive; the namespaced XMP element is unambiguous and needs no gate. `TC260_AIGC_FIELDS` covers **two schemas**: the producer-side one (`Label` / `ContentProducer` / `ProduceID` / `ContentPropagator` / `PropagateID`, Doubao and most China gens) and the **service-provider** one (`ServiceProvider` / `ServiceUser`, plus generic `Time` / `ContentId` which are NOT gated on) — **Tencent Cloud's** AIGC variant (`ServiceProvider` = `腾讯云`), embedded in **EXIF `ImageDescription`**, verified on compatible samples. In `identify`, `aigc` fires on the parsed label **or** the `AIGC_MARKERS` byte scan (the latter preserves the laundering-tell case where the JSON payload is truncated).
**Doubao** (ByteDance) uses it (verified on a public issue sample; `ContentProducer` `001191110102MACQD9K64010000`, no C2PA/SynthID/imwatermark — the XMP block is the only signal; GitHub attachment upload did NOT strip it). The same standard is mandatory for Jimeng/Kling/Qwen/Ernie etc., so the one marker covers the whole China-AIGC-labeled ecosystem. `aigc_label` reads **four image serializations** through a shared `_parse` helper: the HTML-entity-encoded XMP `TC260:AIGC` block in **either RDF form** — the nested element `<TC260:AIGC>{...}</TC260:AIGC>` (Doubao) or the attribute `TC260:AIGC="{...}"` (**PicWish**, `ContentProducer="picwish"`, verified on compatible samples) — via a container-agnostic raw-byte scan (any JSON object accepted), a raw-JSON PNG `AIGC` tEXt chunk (Doubao also writes the label this way, no namespaced marker at all — confirmed on compatible samples, `ContentProducer="doubao"`), a bare raw-JSON `{"AIGC":{...}}` object embedded in **JPEG EXIF (UserComment)** by some China-served generators, brace-matched from the scan head with `json.JSONDecoder().raw_decode` (no namespaced marker, no PNG chunk — confirmed on compatible samples, `ContentProducer="001191440300708461136T1308L"`), **and** a bare `AIGC{...}` blob (the label glued straight to its JSON, no `"AIGC":` key wrapper) embedded in a **JPEG APP segment near the JFIF header** — confirmed on compatible samples. The two raw-JSON forms are scanned in one loop (`'"AIGC"'` then `AIGC{`) that **falls through on a non-TC260 / undecodable hit instead of returning** — a quoted `"AIGC"` can appear later in an XMP packet while the real label is a bare `AIGC{...}` earlier in the file, so an unconditional early return on the quoted form would shadow the bare form (the exact bug behind the 06-10 misses). Native MP4/MOV is a fifth serialization: TC260-PG-20257A stores an `AIGC` key in `moov.udta.meta.keys` and the raw JSON in the matching `ilst` item; Doubao's iOS export additionally writes two QuickTime-form variants (a bare `meta` box as a direct `moov` child, and a keyless `hdlr=mdir` metadata list whose `ilst` data items carry the JSON with no key name) — both verified on retained carriers (2026-08-17). The seeking parser reaches a tail `moov` without reading `mdat`; removal replaces the key with `free` and blanks the validated value at the same length so every box size and stream offset stays fixed. All generic forms are gated on at least one TC260 field (`TC260_AIGC_FIELDS`) so a generic `AIGC` key cannot false-positive; the namespaced XMP element is unambiguous and needs no gate. `TC260_AIGC_FIELDS` covers **two schemas**: the producer-side one (`Label` / `ContentProducer` / `ProduceID` / `ContentPropagator` / `PropagateID`, Doubao and most China gens) and the **service-provider** one (`ServiceProvider` / `ServiceUser`, plus generic `Time` / `ContentId` which are NOT gated on) — **Tencent Cloud's** AIGC variant (`ServiceProvider` = `腾讯云`), embedded in **EXIF `ImageDescription`**, verified on compatible samples. In `identify`, `aigc` fires on the parsed label **or** the `AIGC_MARKERS` byte scan (the latter preserves the laundering-tell case where the JSON payload is truncated).
Native MKV/WebM is a sixth serialization. TC260-PG-20257A stores
`TagName=AIGC` and the raw JSON `TagString` in
@@ -64,12 +64,9 @@ payloads. Removal remuxes either container through ffmpeg with stream copy.
may carry IPTC metadata but no registered C2PA or pixel watermark. The open
DWT-DCT decoder only applies when the producing pipeline actually ran its
encoder and the carrier remains decodable.
- **Invisible but NOT locally detectable (proprietary, API/oracle only):**
Amazon Titan Image Generator + Nova Canvas (Bedrock
`DetectGeneratedContent` API), Kakao (new SynthID image adopter, May 2026),
and NVIDIA Cosmos (SynthID video). No public payload decoder is available;
these signals have no measured local payload decoder here.
- **C2PA 2.4 "Durable Content Credentials" (April 2026; verified against the spec) raise the bar for metadata stripping.** 2.4 defines soft bindings (an invisible watermark or a content fingerprint) plus a server-side manifest repository and a new `c2pa.repository-receipt` assertion. Per the spec: "if a C2PA manifest is removed from an asset, but a copy of that manifest remains in a provenance store elsewhere, the manifest and asset may be matched using available soft bindings." So our local `metadata --remove` deletes the *embedded* manifest, but a fingerprint/watermark soft binding can still re-link the image to its manifest in a repository server-side. Stripping the file is becoming necessary-but-not-sufficient against durable provenance. (Our parsers target the stable embedded-manifest format documented in C2PA 2.1 §11; that format is unchanged in 2.4 -- the new pieces are repository/soft-binding infra, not the on-file box layout, so no parser change is implied.) Spec: https://spec.c2pa.org/specifications/specifications/2.4/specs/C2PA_Specification.html We now READ the soft-binding `alg` (`C2PA_SOFT_BINDINGS` / `soft_binding_vendors_in`) to name the forensic-watermark vendor, and locally DECODE the one open scheme, Adobe TrustMark (`trustmark_detector`); the rest (Digimarc/Imatag/Steg.AI/...) stay name-only (proprietary decoders).
- **Invisible but NOT locally detectable (proprietary, API/oracle only — same wall as SynthID):** Amazon Titan Image Generator + Nova Canvas (Bedrock `DetectGeneratedContent` API), Kakao (new SynthID image adopter, May 2026), NVIDIA Cosmos (SynthID video). No local detector possible; treat like SynthID.
- **C2PA 2.4 "Durable Content Credentials" (April 2026; verified against the spec) raise the bar for metadata stripping.** 2.4 defines soft bindings (an invisible watermark or a content fingerprint) plus a server-side manifest repository and a new `c2pa.repository-receipt` assertion. Per the spec: "if a C2PA manifest is removed from an asset, but a copy of that manifest remains in a provenance store elsewhere, the manifest and asset may be matched using available soft bindings." So our local `metadata --remove` deletes the *embedded* manifest, but a fingerprint/watermark soft binding can still re-link the image to its manifest in a repository server-side. Stripping the file is becoming necessary-but-not-sufficient against durable provenance. (Our parsers target the stable embedded-manifest format documented in C2PA 2.1 §11; that format is unchanged in 2.4 -- the new pieces are repository/soft-binding infra, not the on-file box layout, so no parser change is implied.) Spec: https://spec.c2pa.org/specifications/specifications/2.4/specs/C2PA_Specification.html We now READ the soft-binding `alg` (`C2PA_SOFT_BINDINGS` / `soft_binding_vendors_in`) to name the forensic-watermark vendor, preserve the structured assertion's signed `value`, and locally DECODE the one open scheme, Adobe TrustMark (`trustmark_detector`); the rest stay name-only unless a compatible decoder is independently verified.
- **Microsoft Paint and Photos InvisMark (reverse-engineered 2026-08-20):** Paint receives a per-generation GUID from remote prompt moderation, embeds it into locally generated pixels, and records the same value in `c2pa.soft-binding` under `com.microsoft.invismark.1`. The C2PA soft-binding registry independently identifies that algorithm as Microsoft Responsible AI InvisMark for image and video. Paint's 144-bit writer framing does not match the public repository's 100-bit pretrained checkpoint interface, so compatibility is not assumed. The parser reports the signed identifier; there is no validated local pixel decoder. Microsoft's external Content Provenance Detection API is the removal oracle because it reports `Watermark` separately from `C2PA`; a metadata-stripped, pixel-identical control must remain watermark-positive before an output-negative result is attributed to pixel removal. Sources: https://xusheng.dev/posts/reversing/mspaint_invisible_watermark/main/, https://github.com/c2pa-org/softbinding-algorithm-list/blob/main/softbinding-algorithm-list.json, and https://learn.microsoft.com/en-us/azure/ai-services/content-safety/how-to/how-to-provenance-detection
- **Built in the dated batch:** soft-binding vendor detection, IPTC Photo
Metadata AI-disclosure fields, C2PA detection and stripping for supported
ISOBMFF video, the optional Adobe TrustMark decoder, and temporally stabilized