Transaction Science f218af5ac0 wai.image.jpegai: the exact decoder decodes the configurations of its bundle's model its vectors hold; two the reference leaves to the machine are refused configuration_undetermined ...

Completeness row C8. The exact decoder (jpegai_decode) decoded one configuration, the
reference codestream's; every other trapped. With the jpegai/v1 bundle (tools_0, the
high-operation-point synthesis, one eICCI pair) it now decodes:
- pictures whose sides are 128, 192 or 256, any display cropping (the post-filters run on the
  displayed picture; eICCI pads a side to a multiple of 4 by repetition);
- beta_displacement_log from -1069 to 702, the chroma one independent or not;
- LSBS off per plane; residual variance scaling and GRFS both off, or GRFS alone (one band);
- each post-filter off; eICCI on any plane subset with the bundle's pair; no colour transform.
Held by 29 configuration vectors (wai-rs/tests/vectors/jpegai/configs/: synthetic pictures the
reference software's encoder coded at each configuration, its rate search off, and header
edits of them), each pinned to its RGB8 (the same digests on Linux x86_64 and macOS arm64),
decoded the direct way to the same bits at every stage, and max|d| = 1 from the reference
decoder's picture on 2.5% to 6.6% of samples (tests/jpegai_configs.rs; wai-jpegai-e2e.yml).

Refused with a new code, configuration_undetermined (D74): residual variance scaling without
GRFS (the reference dequantises it by an integer shift or a float division as its tables sit,
and raises on a CPU) and a signalled colour matrix (a library inverse, applied by its first
row alone; the reference raises before either). Everything else outside scope is refused as
before, each with a vector or a header test showing where.

Readings fixed (D74): the scale's incomplete 8x8 blocks pad with 1411; LEF samples its scale
surface at the binary32 quotient's floor; no colour transform gives the decoded components.
The float ONNX path keeps the reference codestream's configuration alone
(check_reference_configuration). The scale path's text (integer-operators 13.6.1) gains the
picture's sizes, beta and the RVS modes; 13.6.2 states the graphs' declared sizes as maxima.

Second reader: tools/wai_jpegai_header.py (standard library) reads and writes the headers and
gives each codestream's scope; tools/wai_jpegai_configs.py writes the manifest, checks that
reader against it and holds decodes to the reference pictures; tools/wai_jpegai_make_vectors.py
makes the vectors (the edits regenerate byte for byte).

Planted faults (cfg(wai_planted), never in an ordinary build), each caught by the vectors:
likely-pad-index, beta-after-likely, grfs-only-floor, rvs-mode-swap, lef-nearest-round,
icci-pad-index, crop-index, icci-subset-swap, lsbs-off-ignored, ct0-order.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

2026-11-12 04:54:58 -05:00

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