MTK system.img解包

1. 解压
sun@ubuntu:~/ext4$ ls
ext4_utils.tar.gz  make_ext4fs  SIMg2img  system.img temp
sun@ubuntu:~/ext4$ file system.img
system.img: data
//生成 ext4格式的img文件
sun@ubuntu:~/ext4$ ./simg2img system.img system.img.ext4
root@yanfa3-desktop:~/ext4# file ./system.img.ext4
./system.img.ext4: linux rev 1.0 ext4 filesystem data, UUID=57f8f4bc-abf4-655f-bf67-946fc0f9f25b (needs journal recovery) (extents) (large files)
//最后一步挂载，挂载之后就可以随意修改了
sun@ubuntu:~/ext4$ mkdir ./sys_dir
sun@ubuntu:~/ext4$ mount -t ext4 -o loop system.img.ext4 ./sys_dir/
2.打包
sun@ubuntu:~/ext4$ ./make_ext4fs -s -l 512M -a system system_new.img ./sys_dir/
sun@ubuntu:~/ext4$  file ./system_new.img
./system_new.img: data