A caps field nothing reads is a contract nobody honors — and this one shipped
write-only: its single reader anywhere in the workspace was a hardware-gated
assertion inside pf-encode's own AMF smoke test. Both planes send the static
HDR grade out-of-band unconditionally (the native 0xCE datagram per keyframe,
the GameStream 0x010e control message), every first-party client reads
exclusively that path, and none parse in-band SEI — so the host decision the
field was reserved for (suppress out-of-band when the encoder embeds) can
never validly exist. The field's doc contract had also rotted in two
directions: it claimed set_hdr_meta no-ops when false (native AMF and QSV
consume it regardless) and that only Windows direct-NVENC attaches in-band
metadata (AMF and QSV do too). The in-band SEI/OBU emission itself is
untouched — it stays a bonus for stock decoders, documented at the emit
sites; the trait docs now describe the real routing.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
enricobuehlerandClaude Fable 5
f495b201e1