In certain embodiments, a method of partially dual encrypting a digital
video signal involves examining unencrypted packets of data in the
digital video signal to identify a specified packet type. The specified
packet type includes packets occurring in a star pattern approximately
situated at approximately a center of an image; encrypting packets
identified as being of the specified packet type using a first encryption
method to produce first encrypted packets; encrypting the packets
identified as being of the specified packet type using a second
encryption method to produce second encrypted packets; and replacing the
unencrypted packets of the specified packet type with the first encrypted
packets and the second encrypted packets in the digital video signal to
produce a partially dual encrypted video signal. This abstract should not
be considered limiting since embodiments consistent with the present
invention may involve more, different or fewer elements.