you select 8 numbers that represent a 64bit key.
If the image isn't encrypted, the numbers will be
used to encrypt it. If the image is already encrypted,
the numbers will be used to decrypt the image.
notice that some zoom levels will not show the decrypted
image in the preview correctly. At 100% zoom the decrypted
image is correctly displayed for most effects. The
Noise and Cross decryption needs to be applied to
the image to decrypt it, the decrypted image will
not show in the preview.