# Supported signals

This page describes the current support boundary. A check mark means that the
repository contains a corresponding code path. It does not guarantee detection
or removal on every future vendor version.

## Visible marks

The `visible` command registers these mark keys:

| Key | Mark | Expected area | Important limit |
| --- | --- | --- | --- |
| `gemini` | Google Gemini visible watermark (sparkle) | Usually bottom right | Detection includes a false positive gate. |
| `doubao` | `豆包AI生成` | Bottom right | Vendor specific text detector. |
| `jimeng` | `★ 即梦AI` | Bottom right | Vendor specific text detector. |
| `qwen` | `千问AI生成` or the three-lobe Qwen symbol | Bottom right | Separate strict templates cover the text and Qwen Create symbol variants. |
| `wan` | Wan logo and `Wan` wordmark | Bottom right, hugging the corner | Provisional: one real Wan 2.7 Pro export. Requires NCC >= 0.55 and a match that ends within 0.015 of the short side from both edges. |
| `kling` | `可灵AI 3.0` or `KlingAI 3.0` | Bottom right | Separate calibrated silhouettes cover the older CJK and current IMAGE 3.0 Latin variants. |
| `yuanbao` | `元宝` over `AI生成` | Bottom right | Standard two-line variant only. |
| `samsung` | `✦ Contenuti generati dall'AI` | Bottom left | Calibrated for the Italian text variant. |
| `runninghub` | `RunningHub AI生成` | Top left | Strict visual and position gates. |
| `baidu` | `百度 AI生成` | Bottom right | Detector and extended removal footprint. |
| `liblib` | `LiblibAI` | Bottom center | Historical wordmark variant; includes a minimum image size gate. |
| `liblib_pill` | Compact `AI生成` pill | Top left | Auto removal requires LiblibAI metadata or the bottom-center wordmark, plus a flat background under the pill. |
| `microsoft` | One Microsoft white AI-badge variant | Top right | Strict uses the visual gate; auto can use Microsoft provenance for the measured [relaxed gate](module-internals.md#visible-mark-removal). Other documented icon, text, and position variants are not covered. |
| `jimeng_pill` | `AI生成` pill | Top left | Weak detector with additional product and background gates. |
| `generic_ai_label` | Bare `AI生成` text, no vendor wordmark | Bottom right | Brand-less TC260 compliance-stamp fallback (vivo and Xiaomi Gallery AI-edit output confirmed; see [module-internals.md](module-internals.md#generic-bare-ai生成-label)). Font-rendered synthetic asset; **calibrated on a synthetic corpus only**, not a real captured generator screenshot -- treat as weaker evidence than the vendor-tuned detectors above. |
| `openart` | `OpenArt` wordmark (bowtie/infinity icon + brand name) | Frame center, not a corner | Confirmed from one customer-reported production case; no known metadata signal, so the visible mark is the only attribution route. **UNCALIBRATED**: procedurally reconstructed asset, no captured corpus -- see [module-internals.md](module-internals.md#openart-wordmark). |

`--mark auto` evaluates all registered marks and removes every selected match.
Known marks are localized to a mask, then the selected fill backend reconstructs
the masked area.

Marks from other vendors are not detected automatically. Use `erase --region`
when you can select the affected area yourself.

Synthetic canonical examples for every registered image and video mark live in
the [visible-mark gallery](../data/fixtures/visible/README.md), alongside
documented real provider originals where redistribution is cleared. The
canonical examples demonstrate detector geometry and house style; provider
originals exercise vendor raster fidelity.

Provider formats can change independently of the registered key. In particular,
the current LiblibAI sample in the gallery preserves a real new-format output
and its LiblibAI TC260 producer metadata. That metadata corroborates the compact
pill detector; the generic pill shape does not attribute LiblibAI on its own.

### Visible video marks

| Key | Mark | Motion | Important limit |
| --- | --- | --- | --- |
| `sora` | Sora 2 mascot, with or without the wordmark | Moves among frame positions | Requires a temporally recurring visual match; mascot-only matches also require complete-shape correlation, which rejects a measured Veo-diamond cross-match. The older Sora Turbo corner swirl is a different unsupported mark. OpenAI discontinued the Sora app on 2026-04-26 and the Sora API on 2026-09-24, so this covers existing exports only. |
| `veo` | Current four-point diamond and legacy `Veo` text | Fixed bottom-right corner | Uses separate silhouettes and requires a recurring match; a valid C2PA AI claim from another vendor (Google on a Sora match, for example) vetoes a mark its own vendor does not also confirm. Provenance alone does not create a visual detection. 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. |
| `doubao` | `豆包AI生成` text run | Fixed bottom-right corner | Reuses the image engine's synthetic alpha as the template; a stable run of at least 12 frames at confidence >=0.35 is required. Without Doubao TC260 confirmation, the run also needs a strong anchor at >=0.55. |
| `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. A TC260 label naming MiniMax as producer can relax only an existing stable run. |
| `vidu` | Vidu two-loop logo and `Vidu AI` wordmark | Fixed bottom-right corner | Provisional: one real Vidu Q3 export (0.72 per frame at 480-1080p, 0.60 at 360p; the 956 other local videos at most 0.41). Requires an anchored recurring run at >=0.52 with a strong frame at >=0.58. A ShengShu TC260 label confirms the vendor without lowering the bar. |
| `kling` | Kling AI swirl, `KLING AI` or `KlingAI`, version, and optional `PRO` suffix | Fixed bottom-right edge | Combines a synthetic logo rescue with font and capitalization variants, an edge gate, a white-label gate, and anchored temporal recurrence. It also scores the Vidu wordmark, so `vidu` is checked first, and a TC260 label naming a non-Kling producer vetoes the match. |

`video identify`, `video visible`, and `video all` share this registry and the
same temporal arbiter. It is separate from the image registry because selection
is made over a sequence rather than one raster. The default `auto` mode scans
all seven entries in one decode pass and selects the first temporally stable
match in table order, subject to the Veo/Sora overlap exception above; an
explicit mark restricts the scan to that row.
Accepted fills are motion-aligned across adjacent frames by default. The prior
fill contributes only where its warped mask covers the current removal mask and
nearby source context agrees. Scene cuts or disjoint marks retain the
independent frame fill.

## Fill backends

| Backend | Install | Behavior |
| --- | --- | --- |
| `cv2` | `remove-ai-watermarks[visible]` | Classical OpenCV inpainting |
| `migan` | `remove-ai-watermarks[migan]` | MI-GAN through ONNX Runtime; practical learned CPU video tier |
| `lama` | `remove-ai-watermarks[lama]` | big-LaMa through ONNX Runtime; offline video quality tier |
| `auto` | Depends on installed extras | Selects LaMa, then MI-GAN, then OpenCV |

The learned backends download model files on first use.

## Metadata and provenance

The inspection and stripping code handles signals in these groups:

- C2PA Content Credentials and supported cloud manifest references;
- EXIF and XMP generator fields, including structured
  `generationParams.modelName` values from supported generators;
- exact app-export provenance and AIGC disclosures from supported
  ByteDance-family products, with product-only provenance excluded from the
  generated-image verdict;
- IPTC AI disclosure fields;
- PNG text chunks and embedded generation parameters, including keyed
  `workflow` and `prompt` tags in MP4/MOV metadata lists;
- China TC260 AIGC labels in supported image placements and the normative
  MP4/MOV `moov.udta.meta.keys/ilst`, MKV/WebM
  `Segment.Tags.Tag.SimpleTag`, AVI `LIST/INFO/AIGC`, and FLV
  `script.onMetaData.AIGC` placements, plus the audio placements of
  TC260-PG-202510A: a RIFF `AIGC` chunk in WAV, an ID3v2 `TXXX` frame described
  `AIGC` in MP3, and an `AIGC=` Vorbis comment in OGG, Opus and FLAC;
- xAI and Grok signature-plus-UUID pairs in ordinary EXIF, ImageMagick PNG raw
  EXIF profiles, XMP description/creator fields, PNG Description/Author text,
  and IPTC Caption-Abstract/By-line fields;
- Samsung AI editing markers;
- Higgsfield job metadata (the `hf-job-id` PNG chunk);
- open Stable Diffusion style DWT-DCT watermarks with the `detect` 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. 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.

C2PA soft-binding names and their official `watermark` or `fingerprint` type come
from a generated snapshot of the
[C2PA registry](https://github.com/c2pa-org/softbinding-algorithm-list). A registry
match names the declared algorithm but does not imply local payload decoding.
`identify` keeps both kinds in the generic `soft_binding` signal; only watermark
entries enter the watermark inventory, while a fingerprint remains a
re-linkability warning, never selects pixel regeneration, and does not suppress
independent SynthID evidence.

The opt-in `classify_source` API is not an `identify` signal. It can suggest an
OpenAI or Google source/export pipeline after metadata removal, but it neither
detects nor decodes a watermark and never changes the provenance verdict.

## File and container formats

Pixel based image commands discover these extensions:

- PNG;
- JPEG (`.jpg`, `.jpeg`, `.jpe`, and `.jfif`);
- WebP;
- HEIC and HEIF;
- AVIF.

HEIC, HEIF, and AVIF pixel decoding requires the independent `heif` extra in
addition to the selected pixel feature. Metadata scanning does not.

Metadata inspection and removal additionally have container paths for:

- JPEG XL metadata;
- MP4, MOV, M4V, and M4A;
- WebM, MKV, MKA, AVI, FLV, MP3, WAV, FLAC, OGG, OGA, Opus, and AAC when
  ffmpeg is available.

JPEG image metadata stripping removes targeted metadata segments without
re-encoding the entropy coded image scan. PNG and WebP removal preserves pixel
values through lossless output paths. HEIC, HEIF, AVIF, and other containers
use their format specific paths.

## Invisible watermarks

The `invisible` command uses diffusion regeneration. A specialized Python API can
instead apply decoder-guided disruption to a positively identified local
Microsoft Paint payload.

Current diffusion pipeline values, all CUDA-only:

- `qwen-zimage`, the default;
- `sdxl-zimage`, the same recipe and the same face stage on an SDXL global pass;
- `chroma-zimage`, the same face stage on a Chroma1 global pass;
- `auto`, sdxl-zimage for Google provenance, chroma-zimage for Microsoft,
  otherwise qwen-zimage.

The `controlnet`, `sdxl`, `qwen` and `default` values were removed. A retired name
is rejected at parse time rather than remapped onto a surviving profile.

Google does not publish the SynthID payload decoder. This package does not
ship a local pixel detector for that watermark. Research on a periodic
lattice expert is in [synthid-detector-research.md](synthid-detector-research.md)
and `scripts/synthid_runtime/`.

The tool recognizes presence from supported provenance: Google AI C2PA
under Google's all-media watermark policy, and current OpenAI C2PA carrying an
explicit `c2pa.watermarked.*` action. Two Google signers are exceptions.
YouTube re-signs uploads as Google LLC (certificate `YouTube Video Processing
Services`, actions `opened` and `transcoded`, measured on Studio downloads), so
a YouTube-signed manifest establishes SynthID only through a SynthID action in
its chain, as a Gemini ingredient carries; with no AI claim in the chain,
`video identify` reports unknown. A Photos-signed AI edit is reported as
"Google Photos (AI edit)" with SynthID present, although the Photos manifest
records no SynthID action and Google documents the mark only for Reimagine:
Google's checker found SynthID in all four Photos AI edits tested on 2026-09-25
(Ask, eraser and two other edits), and a caveat says the claim rests on that
measurement. Legacy OpenAI C2PA without that action
does not assert SynthID. GPT Image 2.5 Flare and Sunburst were verified on
2026-09-15: both API outputs carried valid OpenAI C2PA with
`c2pa.watermarked.unbound` and exercised the existing model-independent OpenAI
route. Automatic routing selected `qwen-zimage` with the OpenAI strength cohort,
and both outputs cleared the official OpenAI SynthID check.

Provider verifiers and provenance APIs are reserved for development-time
calibration. They are not exposed through the installed CLI, the top-level
Python API, or `identify`; production reports only locally available evidence.

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.

For Paint's local `Watermarker.dll` format, the reader recovers the repeated
144-bit message and requires its prefix, GUID byte order, checksum, and per-bit
support. A caller can additionally require agreement with the UUID signed in
pristine C2PA. Only a positive local payload uses decoder-guided bit disruption;
the encoded output is read back and must no longer contain a valid local payload
before it is published. A Microsoft
soft-binding declaration without a matching local payload, including the
committed cloud Image Creator fixture, is rejected by this decoder. The CLI and
high-level API retain their Chroma diffusion route. Metadata stripping alone still
removes only the manifest.

This is local payload invalidation, not external removal certification. The
available Azure Content Provenance Detection API did not detect a known-positive
local-format control, so it cannot certify this direct output. Photos and future
Paint builds may use another pixel format and therefore remain on the regeneration
fallback unless this decoder positively identifies them.

Meta Muse Image stamps every output with Content Seal, a proprietary invisible
pixel watermark, and ships no visible mark (the legacy `Imagined with AI`
corner mark belongs to the pre-2026 Imagine pipeline and is not registered).
This project has no local Content Seal decoder. Meta Model API outputs and
Meta CDN copies carry an XMP `iptcExt:DigitalSourceType =
trainedAlgorithmicMedia` companion tag, which `identify` reports through the
existing Made-with-AI path; that IPTC code is a standard, not a Meta-exclusive
signal, so it neither asserts Content Seal nor selects a strength cohort. The
external oracle is `https://meta.ai/identification`: anonymous, no login,
accepts image, video, and audio, enforces an unspecified daily identification
limit, and answers with model attribution (`Muse Image 1 - Meta`) plus a
per-generation ID and creation timestamp read from the watermark payload. No
identification endpoint exists in the Meta Model API itself (the reference at
dev.meta.ai documents only generation and edits for images), and the official
documentation never mentions the seal. The
default `qwen-zimage` profile clears Content Seal at the default
resolution-adaptive strength (oracle-verified on 2.56 MP generations); measured
strength boundaries are recorded in `data/contentseal/manifest.csv` and
[module internals](module-internals.md#meta-content-seal-boundaries-for-qwen-zimage).
The derived Meta floor (0.1 by the standard spread method) ships as a measured
cohort. `invisible --vendor meta` (also `all` and `batch`, and
`InvisibleOptions.vendor` in the API) selects it when the source is independently
known. An explicit vendor implies the scrub runs: naming the cohort asserts the
pixel watermark is present.
The seal survives resizing, JPEG recompression, and metadata stripping; it dies
to center crops of a third to a half, matching the Reuters 2026-07-11 finding
that Meta's detector missed 55% of cropped Muse images.

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
decoder. A fresh source-positive, output-negative pair from Gemini's built-in
SynthID verifier is an optional per-file audit. A normal Gemini answer may instead
infer from a visible logo or metadata; asking it to reinterpret a completed
verifier result is not a second oracle run.

The optional `detect` extra is different: it provides a local decoder for the
open DWT-DCT watermark used by some Stable Diffusion, SDXL, and FLUX workflows.
That signal is carrier and transformation sensitive, so a negative is still
not a universal clean verdict.

## Provider overview

| Provider or family | Visible | Invisible path | Metadata or provenance |
| --- | --- | --- | --- |
| 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 | Diffusion regeneration for supported invisible signals | C2PA and generator provenance |
| Meta Muse Image | None on Muse output (legacy `Imagined with AI` unregistered) | Diffusion regeneration for Content Seal, oracle-verified on the default profile | XMP IPTC `trainedAlgorithmicMedia` companion tag; no local Content Seal decoder |
| Microsoft Paint local `Watermarker.dll` format | None registered | Local repeated-payload decoder and decoder-guided disruption; no usable external oracle for this format | Paint C2PA soft-binding algorithm and matching UUID |
| Microsoft cloud and other InvisMark variants | None registered | Chroma regeneration fallback | Microsoft C2PA attribution and soft-binding declaration |
| Microsoft image outputs (measured variant) | One top-right white AI-badge variant | No registered pixel decoder | C2PA attribution |
| 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 | 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 AI | Kling AI image and video marks | No registered pixel decoder | TC260 AIGC |
| Vidu (ShengShu) | Vidu video mark | No registered pixel decoder | TC260 AIGC in the MP4 `AIGC` key |
| Runway | None measured on paid-plan output | No registered pixel decoder | C2PA signed `RUNWAY AI, INC.` on its own models; third-party models keep their vendor's manifest |
| Amazon Bedrock (Nova Canvas, Nova Reel) | None | Invisible watermark readable only through the Bedrock API | C2PA signed `Amazon Web Services, Inc.`, claim generator `Amazon Bedrock` |
| Wan (Alibaba) | Wan image mark | No registered pixel decoder | TC260 AIGC in XMP |
| Hailuo AI / MiniMax video | Hailuo AI composite video label | No registered pixel decoder | TC260 AIGC where present |
| Baidu | Baidu mark | No registered pixel decoder | TC260 AIGC |
| LiblibAI | LiblibAI wordmark and compact pill | No registered pixel decoder | TC260 AIGC |
| RunningHub | RunningHub mark | No registered pixel decoder | TC260 AIGC |
| Samsung Galaxy AI | One locale specific mark | No registered pixel decoder | C2PA and Samsung markers |
| Google Photos AI edits | None | SynthID, reported present: Google's checker found it in 4 of 4 Photos AI edits (2026-09-25), though the manifest records no SynthID action | C2PA signed "Google Photos" with a `compositeWithTrainedAlgorithmicMedia` action, plus XMP `photoshop:Credit` `Edited with Google AI` |
| Apple Image Playground and Photos Clean Up | None | No registered pixel decoder; SynthID announced by Apple for a later update | XMP `photoshop:Credit` (`Apple Image Playground`, `Apple Photos Generative Edit: Clean Up`) plus IPTC digitalSourceType; no C2PA on measured 2026-09 output |

For detector thresholds, measured limits, and incident history, see
[module internals](module-internals.md) and
[known limitations](known-limitations.md).