How use the encrypt mode?

[0x2b]

ruuveal [options] --device DEVICE <source.zip> <output.zip>

options:-

--info, -I Displays info about an encrypted zip
--encrypt, -E Set encryption mode
--mainver MAINVER, -m Set the mainver when encrypting
--key KEYINDEX, -k Set the encryption key index
--chunks CHUNKS, -c Set the number of encryption chunks

i see the function with encrypt. now i have the keyfile from bruutveal...how to use it encrypt rom？