Add Seedance and Dola video removal

docs/cli.md

@@ -153,18 +153,21 @@ different container extension.
 Visible video labels and invisible video watermarks are not handled by this
 command.
 
-## Remove a visible Sora or Veo video mark
+## Remove a supported visible video mark
 
 ```bash
 remove-ai-watermarks video visible input.mp4 -o clean.mp4
 remove-ai-watermarks video visible veo.mp4 --mark veo -o veo_clean.mp4
+remove-ai-watermarks video visible seedance.mp4 --mark seedance -o seedance_clean.mp4
+remove-ai-watermarks video visible dola.mp4 --mark dola -o dola_clean.mp4
 ```
 
-The experimental command supports the moving Sora mascot and wordmark plus two
-Veo corner variants: the current four-point diamond and the legacy `Veo` text.
-Sora searches the whole frame at multiple scales. Veo searches the
-bottom-right corner using separate synthetic silhouettes for the two variants.
-Both require a spatially recurring candidate across adjacent frames. Matching
+The experimental command supports the moving Sora mascot and wordmark, two Veo
+corner variants, the Seedance boxed `AI` label, and the `Dola AI` text label.
+Sora searches the whole frame at multiple scales. The other detectors search
+bounded bottom-right regions with separate synthetic silhouettes. Every mark
+requires a spatially recurring candidate across adjacent frames. Fixed marks
+must also remain anchored instead of drifting with a scene object. Matching
 provider provenance may relax the visual score, but metadata alone never
 creates a detection. Clean API exports therefore remain untouched.
 

docs/known-limitations.md

@@ -174,16 +174,19 @@ WebM, Matroska, MP3, WAV, FLAC, OGG, Opus, and AAC container metadata is strippe
 through ffmpeg with stream copying. The operation fails if ffmpeg is absent or
 cannot parse the input.
 
-### Visible video removal supports Sora and Veo and is still experimental
+### Visible video removal is provider-specific and still experimental
 
 The experimental `video metadata` command and high level video API inspect and
 strip supported AI provenance metadata without transcoding streams.
 
 `video visible` and `remove_video_visible` additionally support the moving
-Sora 2 mascot and wordmark, the current Veo four-point diamond, and the legacy
-`Veo` text. Detection requires a recurring visual candidate across adjacent
-frames. Provider provenance can recover low-contrast runs only after visual
-evidence exists, so metadata alone does not erase a clean API export.
+Sora 2 mascot and wordmark, the current Veo four-point diamond, the legacy
+`Veo` text, the Seedance boxed `AI` label, and the fixed `Dola AI` text.
+Detection requires a recurring visual candidate across adjacent frames.
+Seedance, Dola, and Veo candidates must remain anchored rather than drifting
+with a scene object. Provider provenance can recover low-contrast runs only
+after visual evidence exists, so metadata alone does not erase a clean API
+export.
 Historical Sora Turbo exports use a small OpenAI swirl in the corner rather
 than the moving mascot-and-wordmark design; that earlier variant is not
 detected by the `sora` video mark. Other provider video labels and proprietary
@@ -194,9 +197,12 @@ fill is not a motion-aware video inpainting model. OpenCV can leave a visible
 smear where the mark overlaps a hard edge or structured texture, and the smear
 can vary over time. MI-GAN and LaMa improve individual frames but do not
 guarantee temporal coherence. The Veo diamond uses a shape mask to limit damage
-outside the symbol, but OpenCV may still soften texture inside it. The current
-encoder also emits a constant-frame-rate output at the decoded stream rate, so
-variable-frame-rate preservation is not yet guaranteed.
+outside the symbol. Seedance fills the full localized box because a synthetic
+outline mask left part of the real translucent border visible in an end-to-end
+check. OpenCV may therefore soften texture inside that small box; use MI-GAN or
+LaMa when reconstruction quality matters. The current encoder also emits a
+constant-frame-rate output at the decoded stream rate, so variable-frame-rate
+preservation is not yet guaranteed.
 
 Native TC260 metadata in MP4/MOV is supported at its normative
 `moov.udta.meta.keys/ilst` placement, including non-faststart files whose

docs/module-internals.md

@@ -115,32 +115,34 @@ only a `Segment.Tags.Tag.SimpleTag` pairing `TagName=AIGC` with a JSON
 those container tags without transcoding the encoded streams.
 
 [`video_visible.py`](../src/remove_ai_watermarks/video_visible.py) implements
-the first pixel stages for Sora and Veo. The Sora detector searches a normalized
-frame with a fully synthetic mascot-and-text silhouette at several scales. The
-Veo detector uses separate synthetic silhouettes for the current four-point
-diamond and legacy `Veo` text, with bounded bottom-right searches calibrated
-independently from Sora. A strong relocated-diamond match may bypass the known
+the first pixel stages for Sora, Veo, Seedance, and Dola. The Sora detector
+searches a normalized frame with a fully synthetic mascot-and-text silhouette
+at several scales. The Veo detector uses separate synthetic silhouettes for the
+current four-point diamond and legacy `Veo` text. Seedance uses a synthetic
+rounded boxed-`AI` silhouette, while Dola uses an OpenCV-font `Dola AI`
+silhouette. All fixed-mark searches are bounded to the bottom-right area and
+calibrated independently. A strong relocated Veo diamond may bypass the known
 layout anchors, but weak free-corner matches never enter the temporal arbiter.
-This prevents recurring scene details in clean API exports from being promoted
-to a watermark.
 
 Every per-frame result is untrusted. The provider-specific stabilization
 wrappers share one recurrence implementation, while retaining separate visual
 floors and minimum-run policy. Provenance can relax a low-contrast run only
 after recurring visual evidence exists. Sora transition frames follow the
-nearest confirmed moving position only with Sora provenance. A confirmed Veo
-run can cover low-contrast frames at its fixed position. This separation keeps
-clean API exports from being modified merely because metadata names the same
-generator.
+nearest confirmed moving position only with Sora provenance. Veo, Seedance,
+and Dola additionally require candidates to remain anchored to the start of a
+run. This rejects slowly drifting scene details that still have high
+frame-to-frame overlap.
 
-Removal runs in a second decode pass. Sora and legacy Veo text use padded box
-masks. The square Veo diamond uses a synthetic shape mask so transparent box
-corners do not erase unrelated pixels. Every mask goes through the shared
-`watermark_registry.fill` backends. ffmpeg encodes the changed video stream and
-copies optional audio. The default OpenCV fill is the speed floor; structured
-backgrounds need MI-GAN or LaMa for better reconstruction. Invisible video
-stages must continue to reuse the image and metadata implementations rather
-than copying their logic.
+Removal runs in a second decode pass. Sora, legacy Veo text, Dola text, and the
+Seedance box use box masks. Seedance deliberately fills the complete localized
+box: a synthetic outline mask passed repeat detection but left part of the real
+translucent border visible during visual end-to-end review. The square Veo
+diamond uses a synthetic shape mask so transparent corners do not erase
+unrelated pixels. Every mask goes through the shared `watermark_registry.fill`
+backends. ffmpeg encodes the changed video stream and copies optional audio.
+The default OpenCV fill is the speed floor; structured backgrounds need MI-GAN
+or LaMa for better reconstruction. Invisible video stages must continue to
+reuse the image and metadata implementations rather than copying their logic.
 
 The inherited ISOBMFF metadata path currently reads the complete container into
 memory; replacing that with a streaming box copier is a prerequisite for large

docs/python-api.md

@@ -154,7 +154,7 @@ stream bytes. MKV/WebM inspection recognizes the corresponding
 `Segment.Tags.Tag.SimpleTag` representation; its removal requires ffmpeg for a
 stream-copy remux.
 
-## Remove a visible Sora or Veo video mark
+## Remove a supported visible video mark
 
 ```python
 import remove_ai_watermarks as raiw
@@ -173,14 +173,26 @@ veo_result = raiw.remove_video_visible(
     "veo_clean.mp4",
     mark="veo",
 )
+seedance_result = raiw.remove_video_visible(
+    "seedance.mp4",
+    "seedance_clean.mp4",
+    mark="seedance",
+)
+dola_result = raiw.remove_video_visible(
+    "dola.mp4",
+    "dola_clean.mp4",
+    mark="dola",
+)
 ```
 
 `remove_video_visible` scans the complete video before writing output. It
 combines synthetic multi-scale visual matching with temporal consistency, so an
 isolated lookalike in one frame is not enough to authorize inpainting. The
-supported `mark` values are `sora` and `veo`. The Veo detector recognizes the
-current four-point diamond and the legacy `Veo` text with separate synthetic
-silhouettes.
+supported `mark` values are `sora`, `veo`, `seedance`, and `dola`. The Veo
+detector recognizes the current four-point diamond and the legacy `Veo` text.
+Seedance recognizes the boxed `AI` label, while Dola recognizes its compact
+text label. Each variant has an independent synthetic silhouette and calibrated
+temporal policy.
 
 The returned `VideoVisibleResult` records the total, detected, and removed frame
 counts plus any AI metadata that survived the output encode. The function

docs/supported-signals.md

@@ -35,6 +35,8 @@ when you can select the affected area yourself.
 | --- | --- | --- | --- |
 | `sora` | Sora 2 mascot and wordmark | Moves among frame positions | Requires a temporally recurring visual match; the older Sora Turbo corner swirl is a different unsupported mark. |
 | `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. |
 
 Use `video visible` for this registry. It is separate from the image `visible`
 command because selection is made over a sequence rather than one raster.

docs/watermarking-landscape.md

@@ -56,8 +56,8 @@ the existing ffmpeg stream-copy path removes the tags without transcoding.
 - **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
-  visible Sora and Veo removal. Other visible video logos and proprietary
-  audio-watermark detection remain outside the package.
+  visible Sora, Veo, Seedance, and Dola removal. Other visible video logos and
+  proprietary audio-watermark detection remain outside the package.
   Metadata stripping for supported audio containers is a separate implemented
   path.
 
@@ -90,6 +90,17 @@ pixels or alpha maps from that project: it uses two synthetic silhouettes,
 known-layout searches plus a strong relocated-diamond fallback, and a separate
 temporal arbiter calibrated against raw watermarked clips and clean API exports.
 
+**ByteDance video surfaces use distinct visible labels.** Public Seedance
+showcase clips contain a fixed rounded box with `AI`, while the Dola sample in
+[issue #16](https://github.com/wiltodelta/remove-ai-watermarks/issues/16) uses
+fixed `Dola AI` text. The independent
+[Seedance remover](https://github.com/SamurAIGPT/seedance-2.0-watermark-remover)
+estimates a static corner from a temporal mean frame and edge density. Our
+implementation instead matches provider-specific synthetic silhouettes on
+every frame, then requires an anchored temporal run. This extra anchor check
+was necessary because a moving clean scene detail could retain enough adjacent
+overlap to pass a recurrence-only gate.
+
 **The faint-visible-mark precision/recall wall is fundamental, not a heuristic artifact.** The visible-watermark-detection literature has moved to LEARNED segmentation / object-detection (WDNet WACV'21 arXiv:2012.07616; SLBR ACM MM'21, open code+weights; the PRCV'18 large-scale detector; Su et al. survey 2025), but three verified findings bound what a learned detector actually buys: (1) a claim that a confidence threshold "cleanly separates" true from false matches even with a learned CNN front-end was **REFUTED** in verification (arXiv:1705.08593) -- the precision/recall wall persists even with learned features. (2) Learned detectors need a LARGE, pattern-diverse labeled dataset trained on synthetic composites (PRCV'18: 60k images / 80 watermark classes; CLWD: 60k / 160 marks), and off-distribution degradation is a documented real axis (models trained on limited-pattern LVW transfer worse; diversity of training patterns drives generalization). (3) Inference is cheap (WDNet ~8 ms at 256x256) -- the cost is the data pipeline, not runtime. Net: a learned detector shifts the frontier but does NOT remove the wall; for a SINGLE mark the cheapest next step is a small patch classifier (real-sparkle vs false-positive) on top of the existing NCC localizer, not a full segmentation model. SLBR is a ready baseline. The current NCC + false-positive gate (core-ring brightness margin + gradient-NCC crispness + white-core saturation) is a sound operating point, and the residual miss is the information-theoretic wall the literature confirms.
 
 **Visible-mark landscape beyond the registry.** Meta stamps a visible "Imagined with AI" mark (bottom-LEFT, a small symbol) on its OWN Meta AI / "Imagine" output; for third-party images it relies on C2PA / IPTC, not a visible mark. Samsung Galaxy AI additionally uses a **four-star icon** variant in a corner alongside the localized text wordmark `samsung_engine` calibrates (only the Italian text variant is covered) -- the icon is a distinct, uncovered variant. Every source agrees visible + metadata marks are trivially removable (crop / screenshot, ~2 s), which is the tool's premise.