sudo apt-get install abootimg // install abootimg
abootimg -x boot.img or recovery.img //unpack u .img
mkdir unpck // great folder unpck
cd unpck //go to unpck folder
zcat ../initrd.img | cpio -i //unpack initrd.img
after edit repack
find . | cpio -o -H newc | gzip > ../initrd.img //repack intird.img
cd .. //go back folder
abootimg --create name-boot-or-recovery.img -k zImage -r initrd.img //make recovery or boot img
abootimg --create name-boot-or-recovery.img.img -f bootimg.cfg -k zImage -r initrd.img
If error "boot.img: updated is too big for the Boot Image"
abootimg --create boot.img -k zImage -r initrd.img
abootimg --create boot.img -f bootimg.cfg -k zImage -r initrd.img -c "bootsize=size-in-error-bootsize"