test-user 7dcc922617 feat(probe): solid-fill SynthID carrier probe; corpus reconfirms no pixel detector ...

scripts/synthid_pixel_probe.py is an experimental/diagnostic tool for the
one pixel-domain question that isn't a dead-end: on solid-color fills the
zero-mean residual IS essentially the watermark carrier. Two modes:
'consistency' (mean pairwise NCC of carriers across fills vs random
baseline) and 'removal' (does the pipeline drop the carrier toward
baseline?). Logic validated synthetically (injected carrier correlates,
random noise doesn't, simulated removal collapses it) -- no real fills or
GPU needed.

Running its metric on the corpus independently re-confirms the documented
dead-end for real content: at matched resolution SynthID positives do not
cluster apart from negatives (within-Gemini 0.07; at 1024 px pos-vs-neg
>= pos-vs-pos). An apparent 0.62 among 1254px ChatGPT positives turned out
to be near-duplicate content (5 renders of one prompt at ~0.92; a distinct
ChatGPT image scored ~0 against them), not a shared carrier. The probe is
solid-fills-only; do not use on real content.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

2026-05-24 16:35:39 -07:00

..

synthid_corpus.py

feat(corpus): read HEIC dimensions via macOS sips

2026-05-24 15:55:11 -07:00

synthid_pixel_probe.py

feat(probe): solid-fill SynthID carrier probe; corpus reconfirms no pixel detector

2026-05-24 16:35:39 -07:00