0e03e7496e
Refutes a framing of mine that two documents and the port s exporter were built on, so it is a new page rather than an edit. voice-region-leading-chunk.md read a long cue s three streams as three presentations of one take, and from that came the instruction "take one stream, do not sum", which the port implemented. The open question was which presentation the game plays. It has no answer. Booted with --xma_param_probe=true, the cvar whose own comment says it is keyed to reveal which sub-wave of a movie s .slb the game actually decodes. The guest opens three XMA contexts and decodes all three concurrently: ctx=0 packets=632 byte_size=1294336 ch=2 48000 ADV stream 1 ctx=1 packets=546 byte_size=1118208 ch=2 48000 ADV stream 2 ctx=2 packets=572 byte_size=1171456 ch=2 48000 ADV stream 3 Byte-exact against the three streams payloads taken independently off the disc (RIFF size minus 60). Only these three contexts appear in the run. So a consumer that picks one discards two thirds of what the game mixes. Both "three presentations of one take" and "take one stream" are withdrawn -- and the previous behaviour is not thereby right either, because an equal-gain 1/n sum of channel pairs is not a downmix and the port s measured 6.02 dB loss was real. Neither rule is established; a consumer is authoring. Three concurrent stereo streams is six channels and N stereo streams is how XMA carries multichannel on the 360, which would also explain the 1-or-3-never-2 span census. Recorded as a hypothesis, not a result: all three fmt chunks declare ChannelMask 0x0002 identically, which is not what distinct channel roles should look like. Everything byte-level survives: the leading chunk being stream 1 clipped by our own guard, the 70 + 8 + 17 decomposition, the bank-header discriminator. Reach: one cue, one boot. That 28 cues are 3-stream is decoded; that all three decode concurrently is measured on ADV alone. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01QsEPXWVaEpyfudtR6re1Pd
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.