SteamOS DD+ 1.0.0-beta.1

SteamOS DD+ 1.0.0-beta.1

This first public prerelease packages the accepted SteamOS Dolby Digital Plus
runtime as a Decky Loader plugin.

Included

• Optional DD+ 5.1 and DD+ 7.1 HDMI/eARC profiles.
• Direct switching among stock Stereo, stock 5.1 LPCM, stock 7.1 LPCM, DD+ 5.1,
  and DD+ 7.1.
• Live ELD and PipeWire device discovery; no hard-coded HDMI card or PCM.
• Transactional, user-local installation and removal with exact-file ownership,
  crash recovery, and stock-profile preservation checks.
• The accepted x86_64 E-AC-3 runtime, exact corresponding FFmpeg source,
  third-party notices, and SHA-256 checksums.

Validation completed

• 47 codec, IEC 61937, channel-map, and reference tests.
• Complete legacy deployment, activation, rollback, and recovery test suite.
• Decky backend transaction tests covering all five selections, interrupted
  recovery, exact rollback, and preservation of unrelated defaults.
• TypeScript typecheck and production Rollup build.
• x86_64 packaged-runtime loader and codec self-test in the pinned SteamOS
  builder.

Prerelease boundary

The bundled DD+ runtime is the already accepted Steam Machine build. The new
portable Decky discovery and installer have automated Linux coverage but have
not yet completed a clean-machine hardware acceptance run across multiple
HDMI/eARC endpoints. Back up important configuration and use the plugin's
Remove action before uninstalling Decky itself.

This independent project is not certified, licensed, endorsed, or supported by
Dolby Laboratories or Valve. Review the repository licensing and third-party
notices before redistribution.