Patent ID: 7295615

Claim:
A system for embedding additional information in MPEG video data, said system comprising: means for detecting a video frame in the video data from a video data stream, wherein said video frame is an intra-macroblock of an I-frame or of a P or B-frame; means for extracting data for a small domain from said detected video frame and for buffering said data; means for embedding part or all of the additional information into said buffered small domain data without changing the length of the video data stream based on a determination whether the embedding of all the additional information will change the length of the video data stream and where the embedding of all the additional information is determined to change the length of the video data stream, embedding ½ of the additional data if the embedding of ½ does not change the length of the video data stream, wherein said means for embedding said additional information includes: means for detecting a DC factor in said buffered small domain: means for determining whether the bit length of said DC factor will be unchanged even when said additional information has been embedded, means for embedding said additional information in said buffered small domain, when said bit length will be unchanged; and means for determining whether ½ of said additional information can be embedded when said bit length will be changed, and for embedding said ½ of said additional information in said small domain when embedding is feasible; and means for returning said small domain, in which said additional information has been embedded, to said video data.