HK4E Hdiff Builder

A tool to generate hdiff update files between two versions of an Anime Game. This tool replicates the official patch structure. Output is 1:1 identical to miHoYo’s format, but with improved compression. Unlike miHoYo’s use of ZIP, this tool utilizes 7z and hdiffz.exe with ultra compression settings, producing smaller and more efficient patch files with 100% full compatibility.

Features

• Compares two full game folders (old & new)
• Outputs clean .hdiff.7z update files
• Sequential or parallel diffing
• Multithreaded (configurable)
• Strict version checks
• Full logging

Folder Structure

/your-root-folder/  
├── GenshinImpact_6.0.0/                  ← Old version folder  
├── GenshinImpact_6.1.0/                  ← New version folder  
├── hdiffbuilder.exe                      ← Main executable  
├── config.json                           ← Execution config  
├── game_6.0.0_6.1.0_hdiff.7z             ← Patch output  
├── audio_en-us_6.0.0_6.1.0_hdiff.7z      ← Patch output  
├── audio_ja-jp_6.0.0_6.1.0_hdiff.7z      ← Patch output  
├── audio_ko-kr_6.0.0_6.1.0_hdiff.7z      ← Patch output  
├── audio_zh-cn_6.0.0_6.1.0_hdiff.7z      ← Patch output
└── BeyondAssets_OS_6.1.0.7z              ← Patch output

Also, you can use YuanShen.

config.json

{
  "old_ver": "6.0.0",
  "new_ver": "6.1.0",
  "mode": 0,
  "max_threads": 4,
  "keep_source_folder": true,
  "aggressive_mode": true,
  "log_level": "DEBUG",
  "game": true,
  "audio_en-us": true,
  "audio_ja-jp": true,
  "audio_ko-kr": true,
  "audio_zh-cn": true
}

Parameter	Type	Description
old_ver	string	Old version (folder must exist, e.g. GenshinImpact_6.0.0)
new_ver	string	New version (folder must exist, e.g. GenshinImpact_6.1.0)
mode	int	0 = sequential execution, 1 = parallel execution
max_threads	int	Maximum worker threads (1 to number of CPU cores)
keep_source_folder	bool	If true, retains original version folders after patching
aggressive_mode	bool	If true, process diffing the entire contents of game, not only AudioAssets
log_level	string	One of: "DEBUG", "INFO", "WARN", "ERROR", "FATAL", "NONE"
game	bool	If true, perform diffing for main game files
audio_en-us	bool	If true, include English audio in the diff
audio_ja-jp	bool	If true, include Japanese audio in the diff
audio_ko-kr	bool	If true, include Korean audio in the diff
audio_zh-cn	bool	If true, include Chinese audio in the diff

If the config is missing, it will be created automatically with safe defaults.
If the config is malformed or contains invalid values, the program will terminate with an error and hint.

Usage

1. Place hdiffbuilder.exe in the same folder as both game versions.
2. Edit config.json with correct versions.
3. Run the EXE directly.
4. Output .hdiff.7z files will be generated in the same directory.

Build Instructions

1. Install .NET 9.0 SDK
2. Run compile.bat
3. Output will be in bin/hdiffbuilder.exe

Disclaimer

This tool is for reverse engineering & educational use only.
Not affiliated with miHoYo, Cognosphere, or any official entity.
Do not use this project for public distribution or commercial purposes.