发明名称 Scrambling a compression-coded signal
摘要 This invention provides methods and apparatus for protecting data transmitted using standard compression techniques such as Huffman coding. After input data is preprocessed (filtered, quantized, etc.), the data is encoded using a Huffman coder based on Huffman codes or code books which have been scrambled to change the order of the code books and/or codes from established standard Huffman code books and/or codes. When the transmitted information is received by a Huffman code receiver, the received data may be decoded using the scrambled Huffman code book/codes to obtain the data that was transmitted by the transmitter.
申请公布号 US6885749(B1) 申请公布日期 2005.04.26
申请号 US19990476463 申请日期 1999.12.30
申请人 AT&T CORP 发明人 CHANG TZU-CHIEH;QUACKENBUSH SCHUYLER REYNIER;SNYDER JAMES H
分类号 H03M7/30;H03M7/40;H04L9/00;(IPC1-7):H04K1/00;H04N7/167;G06F7/00 主分类号 H03M7/30
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