Systems and Methods for Secure Playback of Encrypted Elementary Bitstreams

• US 20200137460A1
• Filed: 11/18/2019
• Published: 04/30/2020
• Est. Priority Date: 12/04/2009
• Status: Active Grant

• Current Assignee: DivX, LLC (f/k/a DivX CF Holdings LLC) (SoftBank Group Corp.)
• Original Assignee: DivX, LLC (f/k/a DivX CF Holdings LLC) (SoftBank Group Corp.)
• Inventors: Chan, Francis Yee-Dug, Soroushian, Kourosh, Wood, Andrew Jeffrey
• Granted Patent: US 11,102,553 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04N 21/2351 involving encryption of additional data arrangements using cryptography for the use of broadcast information or broadcast-related information H04H60/23
• CPC Class Codes: H04N 21/23614 Multiplexing of additional data and video streams arrangements for simultaneous broadcast of plural pieces of information H04H20/28
• CPC Class Codes: H04N 21/4302 Content synchronisation processes, e.g. decoder synchronisation
• CPC Class Codes: H04N 21/4348 Demultiplexing of additional data and video streams
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/63345 by transmitting keys key distribution for secret or secure communication H04L9/08; network support of key management H04L63/06
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

Systems and methods for providing multimedia content from one process or component to another process or component over an unsecured connection are provided. One embodiment includes obtaining the cryptographic information, extracting the at least partially encrypted video data from the container file to create an elementary bitstream, enciphering the cryptographic information, inserting the cryptographic information in the elementary bitstream, providing the elementary bitstream to a video decoder, extracting the cryptographic information from the elementary bitstream at the video decoder, deciphering the cryptographic information, decrypting the elementary bitstream with the cryptographic information and decoding the elementary bitstream for rendering on a display device using the video decoder.

Claims

1. A playback device for playing back encrypted video, the playback device comprising:

a set of one or more processors; and

a non-volatile storage containing a playback application for causing the set of one or more processors to perform the steps of;

receiving a container file with video data at a parser;

extracting portions of the container file using the parser, wherein the container file comprises video data with a partially encrypted frame, a frame key index that references a frame key by which a portion of the partially encrypted frame is encrypted, and a block reference that identifies the encrypted portion of the partially encrypted frame, and wherein the partially encrypted frame contains encrypted portions and unencrypted portions of data;

providing the partially encrypted frame, the frame key index, and the block reference from the demultiplexer to a video decoder;

identifying the frame key by which the portion of the partially encrypted frame is encrypted using the frame key index and a key table stored on the video decoder;

identifying the encrypted portion of the partially encrypted frame using the block reference;

decrypting the encrypted portion of the partially encrypted frame using the frame key and the video decoder; and

decoding the decrypted portion of the frame for rendering on a display device using the video decoder.