Problem: camera RAW is at 0% (docs/codec-parity.md, #383). CinemaDNG,
the one cinema RAW format with a public specification, could not be
read at all.
Fix: new L0 crate filmcraft-dng, written from the public DNG 1.4-1.7,
TIFF 6.0 / TIFF-EP, ITU-T T.81 and CinemaDNG specifications only (no
other decoder's source read; editions in the crate README):
- TIFF container with SubIFDs, bounded (64 IFDs, 4 levels, cycles end
the walk) and checked offsets; the main raw IFD is the largest
NewSubFileType 0 CFA / LinearRaw image.
- Raw data: 1-16-bit uncompressed (MSB-first packing) and lossless JPEG
(process 14, predictors 1-7, 1-4 components, point transform, line
restarts), strips and tiles, tiles decoded in parallel; allocations
capped by size and by the data present.
- Processing per the DNG model: ActiveArea, LinearizationTable, per-site
black levels with deltas, white levels, as-shot white balance with
neutral highlight clipping, Malvar-He-Cutler Bayer demosaic (bilinear
for other patterns), DefaultCrop, ColorMatrix / CameraCalibration /
ForwardMatrix with illuminant interpolation, Bradford to linear
Rec. 709, BaselineExposure; output scene-linear RGBA floats.
- CinemaDNG FrameRate, TimeCodes and ReelName tags.
- A test-only writer (feature `writer`) synthesises DNGs. Tests: raw
samples bit-exact for every depth / predictor / layout, processing
against hand-computed values, hostile files (every truncation, 12k
mutations, cyclic IFDs, huge sizes, bad offsets), and LibRaw's
unprocessed_raw as an external oracle reading the same samples
(skipped when not installed).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
vangel76