From ff0937fa8a433900f3cc87caf9acc2a00fda7062 Mon Sep 17 00:00:00 2001 From: MechaCat02 Date: Sat, 29 Aug 2026 11:12:38 +0200 Subject: [PATCH] port: pin the 5.1 downmix matrix explicitly -- human decision The RE agent escalated this rather than picking, correctly: folding centre into L/R changes how dialogue sits against the music, which is an aesthetic judgement about the game and not a container detail. Decided: explicit ITU fold, centre at -3 dB, recorded in the manifest with the rest of the transcode command. Pinned rather than defaulted because a default is a decision nobody made -- invisible in the output and free to change between ffmpeg versions. --- docs/MISSION.md | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/docs/MISSION.md b/docs/MISSION.md index 3333b637..cc2be83b 100644 --- a/docs/MISSION.md +++ b/docs/MISSION.md @@ -121,6 +121,28 @@ your own authority. Only the boot intro and the one new-game intro are in scope. The disc holds 3.3 GB of video; transcoding all of it is not this milestone. +### The downmix is decided: pin it explicitly + +**Human decision, 2026-08-29.** The cinematics are 5.1 (see +[`movie-audio-channels`][mac] for the disc-wide split — 28 surround, 69 stereo, +and *both* movies this milestone needs are surround). Fold to stereo with an +**explicit matrix**, not ffmpeg's default: + +``` +-af "pan=stereo|FL=0.707*FC+1.0*FL+0.707*FLC+0.707*BL+0.707*SL|FR=0.707*FC+1.0*FR+0.707*FRC+0.707*BR+0.707*SR" +``` + +Centre at −3 dB into both channels, which is the standard ITU fold and keeps +dialogue sitting correctly against the music. Record the full command in the +manifest, per the rule above. + +Pinned rather than left to the default because a default is a decision nobody +made: it is invisible in the output, it can change between ffmpeg versions, and +it silently alters how speech sits in the mix. Adjust the matrix if it sounds +wrong — but adjust it *deliberately*, as a commit. + +[mac]: https://git.mc02.dev/fabi/Syplheed-Reborn/src/branch/main/docs/re/structures/movie-audio-channels.md + ## 7. Out of scope 3D, gameplay, HUD, missions, save/load, localisation beyond English, the Ready