13bc0b02f7
The Decoder's closing point -- the inference is cheap and the measurement looks expensive right up until someone does it -- is actionable, so the probe I reverted is now permanent. The exporter records each transcode's duration and frame rate in the manifest (probed from the file it wrote, not the source), and every video run prints what it showed against what the media holds. An instrument that has to be added before the question can be asked will not be there the next time somebody reasons instead. Then the instrument corrected me twice more. It is an UPPER BOUND, not a count. It counts engine frames, and the engine renders the UI at its own rate: on a quiet box ADV drew 6480 frames across a 4123-frame video, 44 fps against the media's 30. Above that crossover it constrains nothing, and '157% presented' is the counter used outside its range. The report now says so instead of printing a percentage. So 'the player skips, heavily' is not supported. At 8.3 engine fps under contention S00A could not have shown more than 28% -- a valid bound under contention and nothing more. Quiet, the bound is 88-90%, permitting anything from no drops to a tenth. And the 720p-versus-432p contrast is refuted -- the finding I sent them twice. I reported ADV +6.7% against S00A -0.5% and built 'heavy decode falls behind, light keeps up' on it. Quiet, both run +6.7...+6.9%. The -0.5% was a contended run in which the player dropped frames to hold schedule. I was measuring which run happened to share the box and reading it as a property of the resolution. What survives is sturdier than either: playback runs +6.7%...+6.9% long on this container, five runs, both videos, quiet, resolution-independent. Three corrections in three iterations, all mine, all the same shape: argued from an absence; measured and over-read; then found the measurement was taken under a confound I introduced myself by running the suite alongside it. Their rule needs a companion -- ask what the quantity can be skipped by, and ask what else was running. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01N7FiFFFwbvG2uxdcEh8HyF
Sylpheed
A clean-room reverse engineering and port project for Project Sylpheed: Arc of Deception (Xbox 360, 2007).
Three things live here, in one repository so that a change spanning them lands as one commit:
| The decoders | crates/sylpheed-formats — the disc's formats, read and verified disc-wide |
| The port | port/ — a Godot 4 project, plus crates/sylpheed-export which converts a disc into the open asset tree it reads |
| The corpus | docs/re/ — what has been reverse engineered, with its evidence, its retractions and its dead ends |
You need your own copy of the game. No game content is in this repository and none ever will be. The exporter reads the disc you supply.
The oracle is the real game
sylpheed-cliand the Explorer are tools for verifying our decoding. They are hypotheses under test and they have been wrong. When something must be checked against the truth, the truth is the game running in Xenia Canary, captured — not any renderer of ours.
This is stated first because getting it backwards is the most expensive mistake this project has made.
Layout
crates/
sylpheed-formats/ the decoders. Disc-wide verified; the corpus is its spec
sylpheed-cli/ headless tools -- render a screen, dump a table, probe audio
sylpheed-viewer/ the Explorer: a human's window onto the disc. STATIC data only
sylpheed-export/ disc -> the open, moddable asset tree
port/ the Godot 4 project. Reads open formats ONLY
authored/ decisions that are NOT on the disc, each with its reason
data/
base/ generated by the exporter. Gitignored, never hand-edited
mods/ drop-in overrides. Yours
docs/
re/ the corpus: findings, refutations, method traps
game/ how the game is navigated -- menus, modals, flight
port/ the port's mission, its handoff contract, modding rules
agents/ how the agent team works together
tools/ capture harnesses, probes, the share tool
exchange/ transient inter-agent files. NOT in git
docker/ the agent containers
Where to start
docs/re/INDEX.md— what is decodeddocs/re/REFUTED.md— what has been tested and dieddocs/re/METHOD.md— traps this project has already paid fordocs/game/navigation.md— how the game is navigateddocs/port/MODDING.md— why the asset tree looks the way it does
Xenia Canary is a separate repository: it is a fork tracking upstream, and it carries our instrumentation.
Conventions
Confidence is per claim, never per document: ✅ CONFIRMED · 🟡 PROBABLE ·
❔ HYPOTHESIS · ❌ REFUTED. A withdrawn result is kept with its reasoning
rather than deleted — that is why the numbers here can be trusted.