Slice mask and moat pattern partial encryption

摘要

A selective encryption encoder consistent with certain embodiments of the invention has vertical and/or horizontal stripes encrypted. In one embodiment, packets are examined in the digital video signal to identify a specified packet type, the specified packet type being both packets carrying intra-coded data representing a pattern of horizontal stripes across an image and packets carrying intra-coded data representing a pattern of vertical stripes across an image. The packets identified as being of the specified packet type are encrypted using a first encryption method to produce first encrypted packets. These first encrypted packets are then used to replace the unencrypted packets in the digital video signal to produce a partially encrypted video signal. The packets of the specified type can also be multiple encrypted and replaced in the data stream to produce a multiple encrypted video data stream.