System and method for embedding additional information in video data

Abstract

A method and system for embedding an electronic watermark directly in an MPEG stream is provided. An intra-macroblock of an I-frame or of a P or B-frame is detected in an MPEG stream, and following the detection of an intra-macroblock of the I-frame or of the P or B-frame, data for one macroblock are extracted from the MPEG stream and buffered. An embedding pattern is embedded in the buffered macroblock without changing the length of VLC, and the resultant macroblock is returned to the MPEG stream. More specifically, a DC factor is extracted from the buffered macroblock, and a pseudorandom number is generated to produce an embedding pattern. Then, whether the bit length of the DC factor will not be changed by embedding the obtained embedded pattern is determined. When the bit length of the DC factor not be changed, the embedding pattern is embedded in the buffered macroblock. When the bit length will be changed, whether ½ of the embedding pattern can be embedded is determined. If possible, ½ of the embedded pattern is embedded in the macroblock.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a divisional application of copending U.S. patent application Ser. No. 09 / 763,988, which is a national phase entry of International Application No. PCT / JP98 / 05355 having an International Filing Date of Nov. 25, 1998, the contents of which are hereby incorporated by reference in its entirety. FIELD OF THE INVENTION [0002] The present invention relates to a technique for the embedding of additional information in a video data stream, and in particular to a method and a system for electronically embedding information in MPEG2 video data without changing the length of the VLC (Variable Length Code) that constitutes the MPEG video data portion. BACKGROUND OF THE INVENTION [0003] The data hiding technique (trademark of IBM) is known as a technique for embedding invisible and inseparable data in still picture data, and moving picture data or audio data. This technique is also called electronic watermarking and has received ...

AI Technical Summary

Benefits of technology

This approach allows for efficient embedding and detection of additional information in MPEG2 video data streams without altering the stream's length, supporting packetized formats and reducing buffer requirements, while maintaining low-cost processing and minimizing delay.

Problems solved by technology

This is because the length of the VLC (Variable length Code) would be changed by directly embedding image data in a compressed MPEG2 video data stream, and thus a content packet can not be coped with.

Therefore, a large buffer is required and reconstruction of the bit stream is difficult.

Particularly when DVD data are formed into a packet having a fixed length, the reconstruction of the packet is very difficult.

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