- [x] HEIF item-local length-delimited NAL units, `hvcC`, VPS, SPS, PPS, and the parameter-set and slice-header syntax needed to decode the one independently coded picture carried by a supported still-image item. The production path remains item-local and exposes no Annex B byte-stream API or access-unit/timeline abstraction. Ten official Sony GENERAL Range Extensions first pictures, five real HEIC item payloads, and five public HEIC presentation cases pass exactly in Release: 20 cases with no failures or skips.
- [x] HEIF item-local length-delimited NAL units, `hvcC`, VPS, SPS, PPS, and the parameter-set and slice-header syntax needed to decode the one independently coded picture carried by a supported still-image item. The production path remains item-local and exposes no Annex B byte-stream API or access-unit/timeline abstraction. Ten official Sony GENERAL Range Extensions first pictures, five real HEIC item payloads, and five public HEIC presentation cases pass exactly in Release: 20 cases with no failures or skips.
- [x] One bounded decoder lifecycle owns only the parameter sets, current-picture state, slice/tile entropy state, and reconstructed planes required by that image item. Every allocator-backed child constructor and the owning picture decoder now unwind unpublished rents in reverse order. Focused tests exercise every constructor allocation-failure position and a complete real HEIC reconstruction through 2 KiB allocator groups with balanced exactly-once returns; all 22 official native-plane, real-item, ownership, constrained-allocation, and public presentation cases pass without failures or skips. Both Release source targets build with zero warnings and errors, the scoped Release test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, and `git diff --check` is clean.
- [x] One bounded decoder lifecycle owns only the parameter sets, current-picture state, slice/tile entropy state, and reconstructed planes required by that image item. Every allocator-backed child constructor and the owning picture decoder now unwind unpublished rents in reverse order. Focused tests exercise every constructor allocation-failure position and a complete real HEIC reconstruction through 2 KiB allocator groups with balanced exactly-once returns; all 22 official native-plane, real-item, ownership, constrained-allocation, and public presentation cases pass without failures or skips. Both Release source targets build with zero warnings and errors, the scoped Release test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, and `git diff --check` is clean. Commit `b6ba2dbf2f90c7b0a5d9da4e9f45d045bbce1a65` records the syntax reconciliation and lifecycle correction.
- [ ] CABAC arithmetic decoding and every required context transition.
- [ ] CABAC arithmetic decoding and every required context transition.
- [ ] Coding-tree, coding-unit, prediction-unit, and transform-unit traversal across all permitted sizes and partition modes.
- [ ] Coding-tree, coding-unit, prediction-unit, and transform-unit traversal across all permitted sizes and partition modes.
- [ ] Intra prediction for every luma and chroma mode, including strong intra smoothing and constrained prediction rules.
- [ ] Intra prediction for every luma and chroma mode, including strong intra smoothing and constrained prediction rules.
@ -856,6 +856,7 @@ No valid HEVC or AV1 color, compression, or bit-depth row may remain `unsupporte
- Keep changes vertical and reviewable. A slice should add one behavior, its focused tests, independent evidence, and any required notice update.
- Keep changes vertical and reviewable. A slice should add one behavior, its focused tests, independent evidence, and any required notice update.
- Keep every AV1 prediction family on the established JPEG color-converter operator architecture. Each distinct traversal contract owns a family-named predictor type; its `.Operator.cs` defines the static interface, and its family-named files own the closed generic widest-to-narrowest SIMD traversal. Semantic `readonly struct` operators implement scalar, `Vector128`, `Vector256`, and `Vector512` arithmetic through that contract. Only modes which share the same traversal and contract may share a predictor family; do not nest a separate predictor beneath a broad intra/inter family or create hardware-width-specific class hierarchies.
- Keep every AV1 prediction family on the established JPEG color-converter operator architecture. Each distinct traversal contract owns a family-named predictor type; its `.Operator.cs` defines the static interface, and its family-named files own the closed generic widest-to-narrowest SIMD traversal. Semantic `readonly struct` operators implement scalar, `Vector128`, `Vector256`, and `Vector512` arithmetic through that contract. Only modes which share the same traversal and contract may share a predictor family; do not nest a separate predictor beneath a broad intra/inter family or create hardware-width-specific class hierarchies.
- Keep AV1 forward and inverse transform operators under their family-named `Av1ForwardTransformer` and `Av1InverseTransformer` owners, matching the JPEG color-converter operator architecture. Their `.Operator.cs` files own the static contracts and generic dispatch, while the family-named operator files own each DCT, ADST, identity, and reconstruction-output implementation. Do not nest one-dimensional transform operators beneath a two-dimensional helper or name operator files after an implementation-detail dispatcher.
- Design SIMD-suitable codec work SIMD-first. Establish vector-friendly storage, operator boundaries, scratch ownership, traversal, every applicable lane width, and benchmark-gated dispatch before implementing the equivalent scalar fallback; never build a scalar production architecture and bolt SIMD onto it later.
- Design SIMD-suitable codec work SIMD-first. Establish vector-friendly storage, operator boundaries, scratch ownership, traversal, every applicable lane width, and benchmark-gated dispatch before implementing the equivalent scalar fallback; never build a scalar production architecture and bolt SIMD onto it later.
- Inspect every owning method and upstream invariant before adding guards. Validate external file data at the parser/model boundary and rely on those established invariants internally.
- Inspect every owning method and upstream invariant before adding guards. Validate external file data at the parser/model boundary and rely on those established invariants internally.
- Do not extract one-use helpers merely to label code. Extract shared primitives only when they have genuine reuse or remove substantial complexity.
- Do not extract one-use helpers merely to label code. Extract shared primitives only when they have genuine reuse or remove substantial complexity.
James Jackson-South
5 days ago