qemu-img create -f luks \
--object secret,id=OtherDemo.img_encrypt0,file=/path/to/secretFile \
-o key-secret=OtherDemo.img_encrypt0 \
/var/lib/libvirt/images/OtherDemo.img 5242880K
qemu-img convert --image-opts -n --target-image-opts \
--object secret,id=OtherDemo.img_encrypt0,file=/path/to/secretFile \
driver=raw,file.filename=/var/lib/libvirt/images/sparse.img \
driver=luks,file.filename=/var/lib/libvirt/images/OtherDemo.img,\
key-secret=OtherDemo.img_encrypt0