How to Unpack and Repack boot.img or recovery.img?

AOSP & ROM Development
1

Bootly is a modern Cross-Platform GUI Tool for Android Rom Development

:package: Installation & Usage​

For Developers Cross Platform (Source Code)​

git clone https://github.com/Haris16-code/Bootly.git
cd Bootly
pip install -r requirements.txt
python main.py

For Windows Users (Standalone EXE)​

  1. Download the Bootly-v1.2-windows-x64.zip from the Releases page.
  2. Run Bootly-v1.2-windows-x64.exe.

Source Code : https://github.com/Haris16-code/Bootly/

Unpacking and Repacking Guide

1. Launch Bootly

After running Bootly, it will automatically create three folders in its directory:

  • input/ - Place your boot.img or recovery.img files here
  • output/ - Your repacked images will be saved here
  • working/ - Temporary working directory

image.png1600×679 33.3 KB

2. Select Your Image File

  • Click the Browse button to open the file picker.

untitled-design.png1600×679 35.1 KB

  • The file manager will appear. Navigate to your boot.img or recovery.img file and select it.

3. Unpack the Image

  • Press the Unpack button to begin extracting the image contents.

untitled-design-1.png1600×679 35.1 KB

  • Once unpacking is complete, a popup will appear asking to open the folder where the image is extracted.

untitled-design-2.png1600×677 45.9 KB

  • Click Yes to open the extracted folder. You will also see the extracted image directory in the Workspace Explorer panel.

image.png1600×672 16.6 KB

4. Modify Extracted Files

  • The extracted folder now contains:
    • kernel - The kernel binary
    • ramdisk - The ramdisk image
    • Other configuration files
  • Open and modify any files as needed using your preferred text editor or tool.

Tip: Common modifications include:

  • Editing /init.rc for system configurations
  • Modifying build.prop files
  • Replacing kernel binaries
  • Updating ramdisk components

5. Repack the Image

  • After completing your modifications, go back to Bootly and press the Repack button.

untitled-design-3.png1600×679 34.8 KB

  • A dialog box will appear prompting you to enter a filename for your modified image.

untitled-design-4.png1600×677 124 KB

  • Enter your desired filename make sure dont add .img bootly automatically add file extension (e.g., boot-repacked) and click OK.

6. Completion & Retrieve Your Image

  • Bootly will begin repacking your image with the modifications. Once complete, a success popup will appear.

untitled-design-5.png1600×677 106 KB

  • Click Yes to open the output/ folder where your new repacked image is saved.

Summary Workflow

1. Launch Bootly
   ↓
2. Click Browse → Select your img file
   ↓
3. View image information
   ↓
4. Click Unpack
   ↓
5. Modify extracted files as needed
   ↓
6. Click Repack → Enter filename
   ↓
7. Retrieve your modified image from output folder

Troubleshooting

Common Issues

Q: “bin/ folder not found” error on Windows

  • A: Ensure the bin/ folder is in the same directory as Bootly-v1.1-windows-x64.exe. Do not separate them.

Q: Image fails to unpack

  • A: Verify your image file is a valid boot.img or recovery.img. Corrupted files may fail to unpack.

Q: Repacked image not booting

  • A: Double-check your modifications. Ensure critical files were not accidentally deleted or corrupted during editing.

Q: “Python not found” error

  • A: Make sure Python 3.x is installed and added to your system PATH.

Resources

Bootly Community

Join the development community, share feedback, and collaborate with other Android modding developers:

Join Community: https://bootly.harislab.tech

Contributing

Bootly is an open-source project. We welcome contributions, bug reports, and suggestions!

Developed with :heart: for the Android Community.