sssekai 0.1.1

Project SEKAI Asset Utility / PJSK 资源下载 + Live2D, Spine, USM 提取

sssekai

Command-line tool (w/Python API support) for downloading/deobfuscating the game's assets, along with some other tools.

usage: sssekai [-h]
              {apidecrypt,abdecrypt,usmdemux,abcache,live2dextract,mitm} ...

SSSekai Proejct SEKAI feat. Hatsune Miku (Android) Modding Tools
Installation:
    pip install git+https://github.com/mos9527/sssekai

options:
  -h, --help            show this help message and exit

subcommands:
  valid subcommands

  {apidecrypt,abdecrypt,usmdemux,abcache,live2dextract,spineextract,mvdata,mitm}
                        additional help
    apidecrypt          API crypto dumper
                        This crypto applies to:
                            - API request/response body dumped by packet sniffer (mitmproxy, wireshark, etc.)
                            - AssetBundleInfo (can be found at /sdcard/Android/data/com.hermes.mk.asia/files/data/AssetBundleInfo,or see sssekai.abcache)
    abdecrypt           Decrypt Sekai AssetBundle
                        These can be found at /sdcard/Android/data/com.hermes.mk.asia/files/data/
    usmdemux            Demux Sekai USM Video in a AssetBundle
    abcache             Sekai AssetBundle local cache
                        Downloads/Updates *ALL* PJSK JP assets to local devices.
                        NOTE: The assets can take quite a lot of space (est. 42.5GB for app version 3.3.1) so be prepared
                        NOTE: The AssetBundles *cached* are NOT OBFUSCATED. They can be used as is by various Unity ripping tools (and sssekai by extension)      
                              that supports stripped Unity version (should be 2020.3.21f1. the version is ripped).
    live2dextract       Extract Sekai Live2D Models in a AssetBundle
    spineextract        Extract Sekai Spine (Esoteric Spine2D) Models in a AssetBundle
    mvdata              Query Sekai MV data from AssetBundle
    mitm                Run Sekai API MITM proxy (WIP)

Documentations (WIP)

Supplementary instrutions for some of the scripts (Yes I'm actually writing these now lol)

NOTE: You can always view the script's help output by invoking the script with -h switch. i.e.

sssekai live2dextract -h

Have fun and good luck :)

Acquiring Game Files

abcache was created for it, which allows one to cache all of the game's assets locally without pulling them out from the game's runtime or its own cache folder.

Examples

• Caches the game data into D:\Sekai

  sssekai abcache --cache-dir D:\Sekai
  

• Download game data for a very specific version into D:\Sekai

  sssekai abcache --cache-dir D:\Sekai --platform android --version "3.5.0" --appHash "5e9fea31-2613-bd13-1723-9fe15156bd66"
  

Known Game Versions And Their Respective Hashes

NOTE: This table will probably remain not up-to-date and/or incomplete. PRs are welcome for additions.

platform	version	appHash
android	3.6.0	7558547e-4753-6ebd-03ff-168494c32769
ios	3.6.0	7558547e-4753-6ebd-03ff-168494c32769
android	3.5.0	5e9fea31-2613-bd13-1723-9fe15156bd66
ios	3.5.0	5e9fea31-2613-bd13-1723-9fe15156bd66

Bonus: How to extract appHash from Android releases

• Acquire the game's APK file.
• Run dump_android_pjsk_appHash.py on it. For example:

python dump_android_pjsk_appHash.py pjsk_360.apk

• Which prints

7558547e-4753-6ebd-03ff-168494c32769 production_android
7558547e-4753-6ebd-03ff-168494c32769 production_android
7558547e-4753-6ebd-03ff-168494c32769 production_ios

What Do These Files Do? (WIP)

There's a ton of them. Like ~45GB with version 3.5.0.(!) I'll try to document my limited findings here whenever possible

Spine2D Related Files

NOTE: You'll need Spine2D SDK 4.x to load these.

Path	Purpose (Assumed)
area_sd	Spine2D model files (it's those silly creatures you see in the menu screens). Can be extracted with spineextract

CriWare Related Files

NOTE: USM/HCA files, mainly. For the videos usmdemux can handle it by itself. For audio tracks try vgmstream!

Path	Purpose (Assumed)
live/2dmode/original_mv	Video, Original PV/MVs for selected tracks. Can be extracted with usmdemux. Filenames are the MV IDs which can be queried by mvdata.
live/2dmode/sekai_mv	Video, PV/MVs tailor made for proseka, for selected tracks. Can be extracted with usmdemux Filenames are the MV IDs which can be queried by mvdata.
music/short	Audio, Preview track for the songs.
music/long	Audio, The (ahem still cut though) songs that plays in rhythm game or PV viewer.
music/jacket	Images! The cover art for the songs.

The Charts

You can find them in music/music_score in...SUS Format?

...Anyways, here are some tools you can use to view them https://github.com/paralleltree/Ched

https://github.com/crash5band/MikuMikuWorld

TODO: I'd be really glad to know how to import these back into the game or why is it called SUS for no apparent reasons (jk i love it lmao)

Live2D Related Files

NOTE: Cubism's Live2D edtior comes with a viewer which you can use to view these things

Path	Purpose (Assumed)
live2d/model	Cubism Live2D model files. Can be extracted with live2dextract
live2d/motion	Animation files for the models. Again, Can be extracted with live2dextract

3D Asset Related Files

NOTE: Assets flagged with * can be imported by sssekai_blender_io into Blender

Path	Purpose (Assumed)
live_pv/mvdata	Metadata for the PVs. You can query them by name/id with mvdata
live_pv/model	3D Assets for real-time rendered PVs
live_pv/model/character	*Character models
live_pv/model/characterv2	*Cooler character models. (these sport slightly more advanced NPR techniques like facial SDF but otherwise the mesh topology/material otherwise stays the same)
live_pv/model/stage	*Stage models.
live_pv/model/stage_decoration	*Things that makes the stage cooler. Per-PV. Can be queried by mvdata
live_pv/model/music_item	*PV Props. There aren't lots of those.
And strangly enough there's another folder outside live_pv that also contains 3D assets. I'll put it here.
Path	Purpose (Assumed)
-	-
model3d/model/stage_object	*PV Props, again. Those this time it's all instruments and it has the same aforementioned weighting issues.

See Also

https://github.com/mos9527/sssekai_blender_io