The reverse-alpha text-mark engine (Doubao/Jimeng/Samsung) allocated
full-frame arrays where only the glyph footprint is ever read:
- _fixed_alpha_map / _aligned_alpha_map each built a full (h, w) float32
alpha map non-zero only inside the glyph box, and two were held at once
during removal (~96 MB of mostly-zeros on a 12 MP frame);
- extract_mask built a full (h, w) uint8 mask that every caller cropped to
the located box (~12 MB, rebuilt per text-mark detector on the
memory-tight identify path).
Both now return footprint-sized arrays: the alpha helpers return the
glyph-sized block plus its placement (ax, ay, gw, gh), and extract_mask
returns the box-sized mask. _apply_reverse_alpha consumes the block
directly; the residual inpaint embeds it into one full-frame uint8 mask only
at cv2.inpaint time (which needs a full-frame mask). remove_watermark_
reverse_alpha tracks the winning region alongside best_amap to place it.
Peak allocation drops from O(image*4)x2 + O(image) to O(footprint)x2 +
one gated O(image*1) uint8 mask -- a win every consumer gets, motivated by
the 512 MB raiw.cc worker that OOMs on large decodes. GPU path untouched.
Byte-identical to the old full-frame path (verified: 17 output hashes
across the three engines, inpaint/no-inpaint, detect, and the real
doubao-1.png fixture, unchanged before/after). tests/test_text_mark_memory.py
guards it by reconstructing the old full-frame path inline and asserting
equality, so the proof survives a cv2/asset bump, and pins the O(footprint)
shape so a regression to full-frame fails loudly.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The free `visible` path over-subtracted a faint Gemini sparkle on a
mid-tone background into a darker-than-background brown diamond instead
of removing it (2026-06-18 prod NPS report, "the watermark was not
removed, just its color changed"). The existing over-subtraction guard
only tripped when reverse-alpha drove a footprint pixel fully negative
(the issue #30 dark-background black-pit case); on a mid-tone background
the over-subtraction darkens the core well below the background without
any pixel crossing zero, so the gate missed it and shipped the dark mark.
Add a second over-subtraction signal to `_reverse_alpha_oversubtracts`:
predict the reverse-alpha output at the bright core, (core - a*logo)/(1-a),
and route to the footprint inpaint when it lands more than
`_OVERSUB_DARK_MARGIN` (25) gray levels below the local background ring.
Calibrated wide: clean removals predict within ~12 of background
(demo_banana ~-1), the prod regression ~-40, the issue #30 dark case ~-82.
Corpus-validated on the 479 detected Gemini images: 10 switch reverse-alpha
to inpaint, all of them dark-diamond cases that improve or match; the
other 469 stay byte-identical. demo_banana stays on the reverse-alpha
path (byte-identical).
Also crop both reverse-alpha helpers to the region they actually touch,
a pure O(image) -> O(mark) win that is byte-identical to the full-frame
math (a uint8<->float32 round-trip is exact):
- `GeminiEngine._core_and_bg` converts only the footprint+ring crop to
gray, not the whole frame (~70 ms -> 0.1 ms on a 12 MP image; it runs
for both the alpha-gain estimate and the new gate). Verified identical
across 479 images; detector confidence unchanged.
- `TextMarkEngine._apply_reverse_alpha` computes the blend on the glyph
crop only (`amap` is zero outside it, so the math is a no-op there):
~275 ms -> ~2 ms per placement on a 12 MP frame, up to 2 placements per
removal. Verified identical across 142 Doubao/Jimeng placements.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Nine findings from a high-effort project-wide review, fixed and verified
(571 passed, ruff/pyright clean):
Correctness:
- all/batch now remove Doubao/Jimeng/Samsung visible text marks: the visible
step routes through the registry (new cli._remove_visible_auto) instead of a
hardcoded GeminiEngine, so they no longer leave the wordmark intact.
- batch always reads the original source (dropped the out_path-reuse that
re-processed already-cleaned outputs on a re-run).
- img2img_runner only retries the diffusion call on the deprecated-callback
TypeError; any other TypeError now propagates instead of double-running.
- gemini detect/remove and the reverse-alpha engines normalize channels via a
new image_io.to_bgr, fixing a grayscale/BGRA crash in the FP-gate path.
- _png_late_metadata advances its cursor by the clamped length, so a malformed
chunk length no longer aborts the late AI-label scan.
Cleanup / efficiency:
- Consolidate the ~90%-identical Doubao/Jimeng/Samsung engines into a shared
config-driven _text_mark_engine.TextMarkEngine base; each engine is now a thin
subclass (TextMarkConfig + test shims). Behavior is byte-exact (the three
engine test suites pass unchanged). Registry adapters collapse to one
_text_mark(...) row each. Gemini stays a separate engine.
- scan_head is memoized per (path, size, mtime), so identify() reads the file
head once instead of ~8 times.
- invisible_engine post-processing decodes/encodes the output once (chained in
memory) instead of 2-4 times across stages.
- Remove the orphaned get_model_id_for_profile (+ CONTROLNET_PROFILE); derive
the --strength help from the strength constants (strength_default_help) so it
cannot drift; share the --pipeline/--strength click options; simplify the
retired --auto resolver.
Net -835 lines. Tests added for the registry-routed visible pass, to_bgr,
the polish/model/guidance wiring, and strength_default_help. CLAUDE.md updated
for the new base module, the engine/registry changes, image_io.to_bgr, and the
scan_head cache.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>