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