How to Extract and Read factoryfs.img from a TAR.MD5 Release
(Updated 02/02/2013)

We've all seen those pesky TAR.MD5 packages that we can flash through Odin.  How often have you wanted to look inside them and see what is inside before flashing?  There are several ways to do it and the most common answer requires Linux and Dsixda's Kitchen utility.  This tutorial gives you the ability to do that through Windows and without having to extract the full ROM.  These instructions are specific to the Samsung Galaxy S2 (all variants) but can be used on most Samsung Galaxy phones.

Each TAR.MD5 release contains multiple files.  Each of these files corresponds to a specific partition on your device.  These files are formatted to be mounted by your device but not by a computer.  We will be converting them from a .img partition type to an ext4.img type partition so we can mount them and read them through Windows.  For this tutorial we will be opening up the factoryfs.img (the system files partition).

  • A PC running Windows.
  • A stock TAR.MD5 release.  Several are available in the Stock ROMs section here.
  • DiskInternals Linux Reader (must be installed on the Windows PC).  You can download DiskInternals Linux Reader here.
  • SGS2toEXT4 Utility available here.
    *Be sure to extract the JAR file from the ZIP archive.
  • 7-Zip available here.
  1. Right click on the TAR.MD5 and select Open with 7-Zip.
    A message will popup that says, "There is no correct record at the end of archive."  Press ok and ignore it.
  2. Extract factoryfs.img to your desktop (or folder of choice).
  3. Run the sgs2toext4.jar utility.  A window titled "Drop .img here" will popup.
  4. Take the factoryfs.img icon and drag and drop it into the white space on the "Drop .img here" window.  It will now create a new file on your desktop titled factoryfs.ext4.img.
  5. Close the "Drop .img here" window.
  6. Open DiskInternals Linux Reader.
  7. Select "Mount image" from the column on the left.
  8. Make sure the "Raw Disk Images" option is selected and press Next.
  9. Navigate to where you saved factoryfs.ext4.img and select it.
  10. You will now see a new Hard Disk Drive titled "Linux Ext Volume 1".
    *You can mount multiple ext4 images at one time so make sure you select the right one.
    You can now select the drive and navigate it the same as you would on your device.
  11. To extract a file you select/highlight it and then press save at the top.  This will extract the file from the ext4 partition and save it to Windows.
Congratulations you have unpacked your first factoryfs.img from a TAR.MD5!

If you have additional questions or would like to discuss these methods further please visit the Rwilco12 Android Forums.