Issue #98. cv2's encoders write no container metadata, so every pixel-path
output (all, visible, invisible, erase) came back without its colour profile
and orientation tag, even with --keep-metadata.
imwrite now takes display_tags_from, the file whose decode produced the
pixels, and restores the two display tags into the re-encoded output: PNG and
JPEG by splicing iCCP/eXIf chunks and APP1/APP2 segments into the encoded
bytes, WebP by a lossless Pillow re-save (libwebp hides hand-spliced chunks
from readers without a VP8X header), HEIF through the save call itself.
Orientation is re-tagged only when the raster still has the source's stored
dimensions: cv2 rotates JPEG and (build-dependent) PNG decodes under
IMREAD_COLOR but never IMREAD_UNCHANGED, which is what the pixel paths read
with, so the decision is made against the raster's own shape and cannot
double-rotate.
The default metadata strip now preserves what the restore put back: the PIL
path forwards the profile and a scrubbed EXIF (orientation included) for PNG
and WebP outputs, the 16-bit chunk walker re-emits eXIf scrubbed instead of
dropping it wholesale, and --remove-all actually drops the ICC profile on
every format (Pillow's saver fallback kept it alive, contradicting the
documented "removed by --remove-all").
Mirror and 180-degree orientations (2, 3, 4) stay untagged: no cheap signal
distinguishes a rotated decode from a stored one for them.
Bug fixes (each with a regression test):
- metadata strip parity across every marker placement: IPTC digitalSourceType
in XMP, the Samsung post-EOI trailer, the China TC260 AIGC block in EXIF
UserComment, a bare AIGC block in a non-standard APP segment, and the ISOBMFF
EXIF path (AIGC + xAI) are all now stripped -- anything a scanner flags, the
strip reaches
- Samsung genAIType detected when its trailer sits past the 512 KB scan window
(file-tail read on large photos)
- crashes on edge inputs: Gemini detector on images with a short side < 16px,
footprint_mask on a zero-size ndarray, the humanizer on chromatic_shift >=
width, and the CLI on unreadable/corrupt/empty input (clean error, not a
traceback)
- WebP written losslessly (cv2 quality 101), not lossy at 100
- the IPTC digitalSourceType algorithmicMedia (procedural, not trained on
sampled data) is no longer flagged as AI-generated, so clean procedural
content is not scrubbed
- c2pa source-type: compositeWithTrainedAlgorithmicMedia is checked before the
bare algorithmicMedia token, so an AI-enhanced composite is not misclassified
Detection:
- integrity-clash coverage now normalizes ByteDance / Canva / ElevenLabs /
Black Forest Labs, so a transplanted manifest next to an independent
conflicting stamp is caught; the generic China TC260 AIGC label is attributed
to a co-present TC260 vendor, so a legit Doubao image (its own C2PA + TC260
label) does not clash (corpus-validated: 0 new clashes on 5000 carriers)
CLI:
- batch exits non-zero (with a warning) when any image errors or a GPU-missing
SynthID scrub is skipped, and copies the input through so the output dir stays
complete -- it used to always exit 0 and could silently drop files
Perf:
- GeminiEngine reused as a process-wide singleton with a precomputed template
ladder: -24% on the identify sparkle path, detection byte-identical
Internal: one shared _ai_exif_targets rule set feeds both EXIF scrubbers so
their coverage cannot drift; docs synced; maintain.sh hardened so the uv-secure
internal teardown crash no longer aborts the gate (still fails on a real finding).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Make `pyright src/` strict-clean via a hybrid: pure-logic files are fully typed
(piexif gets a local typings/ stub; PIL info-dict loops guard isinstance(key, str);
progress returns Callable[..., None]; availability checks use importlib.util.find_spec
instead of unused imports), while the irreducibly-untyped cv2/torch/diffusers boundary
files carry a documented per-file `# pyright:` relax pragma (or a ctrlregen
executionEnvironment) that disables only the unknown-type rules. Public ndarray-returning
signatures on the relaxed engines are annotated NDArray[Any] so strict consumers (cli.py)
stay clean.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Victor Kuznetsov