How to extract .backup files created by android stock recovery? I'm using Coolpad note 3 lite, running Android 5.1. I created internal memory backup using stock recovery. Files were created in this format: 


userdata_yyyymmdd_HHMMSS.backup  = 2GB
userdata_yyyymmdd_HHMMSS.backup1 = 2GB
n. ...
userdata_yyyymmdd_HHMMSS.backup5 = 1.53GB


Is there any way to extract the files to PC? I couldn't see file header mentioned here. Another user referred a method, which I couldn't understand.


Android 5.1
TWRP installed
Rooted
FAT32 internal &amp; SD card.
Tried Titanium backup and it don't recognize the format.


Edit:


Tried to do a stock recovery backup and replace the files. While trying to restore stock recovery not showing SD card, although it takes backup in SD card during backup in same session.
7Zip Windows opened the merged .backup file. It shows "2.ext".

Mounting 2.ext in Ubuntu shows nothing even though file space is occupied.

When trying to open 2.ext using 7zip, I see lot of files in similar name and opening them in 7zip again shows again same file names....



Now how do I recovery files from this 2.ext?
As a first step, you will need to merge the various .backupN files into one by using the following command:

cat userdata_yyyymmdd_HHMMSS.backup* &gt; userdata_yyyymmdd_HHMMSS.backup

It looks like the header size of 512 bytes is the same across many devices, so try to extract using the following command:

dd if=userdata_xxxxxxxx_yyyyyy.backup bs=512 skip=1 | gunzip -c | tar xv

If this doesn't work, you can try the other method as described in this post:


Download the simg2img tool from here.
Convert the .backup file into an image using command simg2img userdata_xxxxxxxx_yyyyyy.backup userdata_xxxxxxxx_yyyyyy.backup.raw
Mount the image using command mount -t ext4 -o loop,rw userdata_xxxxxxxx_yyyyyy.backup.raw "data".


You should now be able to copy the contents of the backup image.

Alternatively, you can download the simg2img binary along with the script that automates the above steps using the link from the above mentioned post.