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US5166684A Expired / Lapsed US ⏱️ 0.0 years remaining

Variable length encoder having sign bit separation

Assignee: Panasonic Holdings Corp
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Filing: 1991-11-19
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Granted: 1992-11-24
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Expires: 2011-11-19
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Abstract

Abstract A variable length code encoder is provided in which, during variable length code encoding of video or audio data which has been divided into blocks for ease of transmission or storage, the lowest bit of a particular variable length code in each block of code words which is composed of a special pattern of bits and arranged to appear at no other position than the end of the block, is utilized for carrying a piece of data in addition to the data of the block.

Inventors

  • 👤 Tatsuro Juri
  • 👤 Masakazu Nishino
  • 👤 Hideki Otaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 01:00
CPC Classifications
H; H03; H03M; H03M7/00; H03M7/30; H03M7/40; G; G11; G11B; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1423; G11B20/1426; H03M5/00; H03M5/02; H03M5/04; H03M5/14; H03M5/145; H03M7/42; H04; H04N; H04N1/00; H04N1/41; H04N19/00; H04N19/10; H04N19/102; H04N19/13; H04N19/60; H04N19/90; H04N19/91

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 104 words
A variable length code encoder comprising: a code separating means for separating from an input signal a sign bit which denotes whether a value of the input signal is positive or negative during a process in which video or audio data is divided into blocks and data of each block is converted into a variable length code form for transmission and/or storage; and a means for assigning the sign bit separated by said code separating means to a lowest bit of an end-of-block code word having a special bit pattern which does not appear at any other position than the end of each block.
Claim 2
Dependent Claim 104 words
A variable length code encoder comprising: a code separating means for separating from an input signal a sign bit which denotes whether a value of the input signal is positive or negative during a process in which video or audio data is divided into blocks and data of each block is converted into a variable length code form for transmission and/or storage; and a means for assigning the sign bit separated by said code separating means to a lowest bit of an end-of-block code word having a special bit pattern which does not appear at any other position than the end of each block.
Claim 3
Dependent Claim 46 words
A variable length code encoder according to claim 1, wherein the variable length code encoding is such that both a number of continuous zeros of the input signal and an amplitude of non-zeros following the continuous zeros are simultaneously encoded to one or two code words.
Claim 4
Dependent Claim 137 words
A variable length code encoder comprising: a transforming means for dividing an input signal of video or audio data into blocks and separating a direct-current component from the remaining components of each block; a code separating means for separating a sign bit which denotes whether a value of the input signal is positive or negative from the input signal during variable length code encoding of the data in each block for transmission and/or storage; and a means for assigning the sign bit separated by said code separating means to a lowest bit of an end-of-block code word having a special bit pattern which does not appear at any other position than the end of each block whereby the lowest one bit of the end-of-block code word can carry information related to the direct-current component in the block.
Claim 5
Dependent Claim 137 words
A variable length code encoder comprising: a transforming means for dividing an input signal of video or audio data into blocks and separating a direct-current component from the remaining components of each block; a code separating means for separating a sign bit which denotes whether a value of the input signal is positive or negative from the input signal during variable length code encoding of the data in each block for transmission and/or storage; and a means for assigning the sign bit separated by said code separating means to a lowest bit of an end-of-block code word having a special bit pattern which does not appear at any other position than the end of each block whereby the lowest one bit of the end-of-block code word can carry information related to the direct-current component in the block.
Claim 6
Dependent Claim 16 words
A variable length code encoder according to claim 3, wherein said transforming means performs orthogonal transformation.
Claim 7
Dependent Claim 32 words
A variable length code encoder according to claim 3, wherein the sign bit assigned to the lowest bit of the end-of-block code word is a least significant bit of the direct-current component.
Claim 8
Dependent Claim 46 words
A variable length code encoder according to claim 3, wherein the variable length code encoding is such that both a number of continuous zeros of the input signal and an amplitude of non-zeros following the continuous zeros are simultaneously encoded to one or two code words.

References Cited (Backward Citations)

US4568916A Cited
US4675650A Cited
US4901075A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-11-24 1996-05-25 1996-11-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-11-24 2000-05-25 2000-11-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-11-24 2004-05-25 2004-11-24 $7700.00 Window Closed / Lapsed

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