Method and system for securing compressed digital video

A method for decrypting a protected stream of compressed video content comprising:

• receiving an input stream of compressed video content containing encrypted frames and unencrypted frames;
• receiving frame decryption information necessary to decrypt said encrypted frames, said frame decryption information is synchronized with said set of encrypted frames into a synchronized frame decryption stream and distinguishes said encrypted frames from said unencrypted frames;
• obtaining an applicable frame decryption key from the received frame decryption information;
• and
• decrypting selected portions of said encrypted frames using a frame decryption function in accordance with said frame decryption information, which identifies the specific portions of the frames to be decrypted and the applicable frame decryption key from the frame decryption information.

An encrypting digital video encoder comprising:

• a video processing unit for generating a plurality of input data streams in response to a sequence of uncompressed video frames;
• an entropy compression unit for creating, based upon said plurality of input data streams, compressed video content containing a sequence of compressed frames;
• and
• a video encryption module configured to generate a table of encryption keys;
• wherein the video encryption module is also configured to create a set of encrypted frames by encrypting at least selected portions of selected frames of said sequence of compressed frames using said frame encryption keys in accordance with a frame encryption function;
• wherein the video encryption module is also configured to transform said sequence of compressed frames into a protected video stream containing at least the set of encrypted frames, the unencrypted frames and a synchronized frame decryption stream necessary to decrypt said set of encrypted frames;
• wherein said synchronized frame decryption stream includes encryption key pointers identifying encryption a decryption key to be used in the decryption of each encrypted frame.

A decrypting digital video decoder comprising:

• a video decryption module configured to receive a protected input stream of compressed video content containing at least a set of encrypted frames and synchronized frame decryption stream, said synchronized frame decryption stream being necessary for decrypting said set of encrypted frames so as to form a set of decrypted frames;
• wherein the video decryption module is further configured to obtain an applicable frame decryption key from the received frame decryption stream;
• wherein the video decryption module is further configured to generate the set of decrypted frames by decrypting selected portions of the encrypted frames in accordance with said frame decryption stream, which identifies the specific portions of the frames to be decrypted and the applicable frame decryption key;
• an entropy decompression unit for creating, based at least in part upon said set of decrypted frames, a plurality of video data streams;
• and
• a video processing unit for generating an output stream of uncompressed video content in response to said plurality of video data streams;
• wherein said synchronized frame decryption stream includes encryption key pointers identifying an applicable decryption key to be used in the decryption of each encrypted frame.