# HDR metadata

HDR10, HDR10+, and Dolby Vision Profile 8.1 requirements remain normative in
`IMPLEMENTATION_PLAN.md`, Section 10.

The boundary encoder preserves explicit colour range, primaries, transfer,
matrix and chroma-location fields. Automated application-generated fixtures
verify BT.2020/ARIB STD-B67 HLG at HEVC Main10, Main 4:2:2 10 and Main 4:4:4
boundaries. HDR10 gates verify BT.2020/PQ, mastering-display and content-light
metadata. HDR10+ is serialized from decoded dynamic-metadata side data, wrapped
with the correct ITU-T T.35 registration header, reinjected at the boundary,
and checked for physical per-frame payload coverage. A53 closed-caption side
data is carried into H.264 and HEVC boundary encoders and compared byte-for-byte.

Profile 8.1 Dolby Vision RPU/config preservation is covered by independent
`dovi_tool` parsing and scene-refresh handling as described in `FORMAT_SUPPORT.md`.
Remaining release work is broad manual player and display interoperability;
these checks do not imply Dolby certification.
