AssetStudioWASM

A WebAssembly port of AssetStudio that lets you extract Unity assets directly in memory, enabling web tools to parse, inspect, and serve assets without writing them to disk.

Objectives

Traditional Unity asset extraction tools expect to run on desktop/server environments and often operate on file paths or the filesystem.

But in modern web tools, you may want to:

• Accept an Unity package by upload or URL
• Extract textures/meshes inside the browser or in a serverless function
• Serve extracted assets over HTTP without intermediate files

AssetStudioWASM fills that gap by providing the same core extraction capabilities as AssetStudio, compiled to WebAssembly + .NET, so it can run in browser or in WASM-capable runtimes.

Features

• List Unity assets
• Extract Unity assets in memory, currently supported assets:
  • Texture2D -> PNG
  • AudioClip (original format)
  • VideoClip (original format)
  • TextAsset
  • Font
• No file I/O required (apart from reading the original archive)
• Bridges to JavaScript / Web API
• Compatible with Unity versions supported by AssetStudio
• Reuse of AssetStudio’s parsing logic and data structures

Build

Prerequisites & Setup

Before building or contributing, make sure you have:

• VS Code
• Emscripten SDK installed and configured
• .NET 8.0 SDK

Instructions

1. Clone the repository

   git clone https://github.com/wad8989/AssetStudioWASM.git
   cd AssetStudioWASM
   

2. Ensure Emscripten SDK is activated (e.g. emcc is on your PATH)

3. Open AssetStudioWASM.code-workspace with VS Code

4. Using VSCode's Run and Debug Build WASM / Rebuild WASM, the product will be placed in dist/

5. Using VSCode's Run and Debug Test WASM, you may also try it in browser by serving test/

Update Remarks

If I was too lazy to update to catch up with aelurum/AssetStudio in the future, you can pull the sub-repo yourself.

I did not touch any code from them. As long as the APIs used and reflected are still the same, it could still works.

Usage

Step 1. Import dist/AssetStudioWASM.js

Option A: Import in <script src=>

<script type="module" src="dist/AssetStudioWASM.js"></script>
<script type="text/javascript" id="YOUR_WEB_TOOL">
  window.addEventListener("AssetStudioWASM.loaded", e => {
      var module = /*window.*/AssetStudioWASM;
      // ...
  });
</script>

Option B: Import as module

<script type="module" id="YOUR_WEB_TOOL">
  import "./dist/AssetStudioWASM.js";
  var module = AssetStudioWASM;
  // ...
</script>

Step 2. Load the unity package file

Option A: Load from URL

await AssetStudioWASM.LoadURL(url);

Option B: Load from file

// `file` from `dropEvent.dataTransfer.files[i]` or `document.querySelector('input[type="file"]').files[i]` whatever
const buffer = await file.arrayBuffer();
await AssetStudioWASM.LoadFile(new Uint8Array(buffer), file.name);

Remarks 2.1. Dealing with error "The asset's Unity version has been stripped"

// Add this to specify Unity package version
AssetStudioWASM.SetUnityVersionForStripped("2022.3.44f1");

await AssetStudioWASM.LoadURL(url);
// ...

Step 3. List and Extract assets

let assets = AssetStudioWASM.ListAllAssets();
// ...

// Pick `wanted_asset` from assets
let media_url = AssetStudioWASM.ExtractAssetResource(wanted_asset);
// media_url is blob:url to the .png, .mp4, .ogg, etc

// ...

//REMARKS: Your responsibility to use `URL.revokeObjectURL` to release the memory
URL.revokeObjectURL(media_url);

Thanks

• Perfare — for the original AssetStudio, which laid the foundation of quality
• aelurum (AssetStudioMod) — for continued enhancements, fixes, and community support
• The open-source community at large