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US5473377A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for quantizing intra-block DC transform coefficients using the human visual characteristics

Assignee: WiniaDaewoo Co Ltd
•
Filing: 1994-06-03
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Granted: 1995-12-05
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Expires: 2014-06-03
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Abstract

Abstract The quantization of intra-block DC transform coefficients is improved through the use of human visual characteristics. The method comprises the steps of converting each of the plurality of blocks included in the input digital video signal into a set of inter-block or intra-block DC and AC transform coefficients; selecting an intra-block DC transform coefficient from said set of inter-block or intra-block DC and AC transform coefficients; determining an intra-block DC quantizer step size based on a set of the selected intra-block DC transform coefficients; and generating a quantized intra-block DC transform coefficient from each of the transform coefficients included in the set of the selected intra-block DC transform coefficient through the use of the intra-block DC quantizer step size.

Inventors

  • 👤 Sang-Ho Kim

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 21:31
CPC Classifications
H; H04; H04N; H04N19/00; H04N19/10; H04N19/102; H04N19/124; H04N19/169; H04N19/18; H04N19/126; H04N19/134; H04N19/157; H04N19/159; H04N19/17; H04N19/176; H04N19/60; H04N19/61; H04N19/146; H04N19/152

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 165 words
A method for quantizing intra-block DC transform coefficients for use in a digitized video signal encoder which provides an encoded video signal for transmission from an input digital video signal comprised of a plurality of equal-sized blocks, each of the blocks being either an inter-mode or an intra-mode video signal, said method comprising the steps of: converting each of the plurality of blocks included in the input digital video signal into a set of inter-block or intra-block DC and AC transform coefficients; selecting an intra-block DC transform coefficient from said set of inter-block or intra-block DC and AC transform coefficients; determining an intra-block DC quantizer step size for each set of a predetermined number of selected intra-block DC transform coefficients based on the selected intra-block DC transform coefficients included therein; and generating a quantized intra-block DC transform coefficient from each of the transform coefficients included in each set of the selected intra-block DC transform coefficients through the use of said intra-block DC quantizer step size.
Claim 2
Independent Claim 165 words
A method for quantizing intra-block DC transform coefficients for use in a digitized video signal encoder which provides an encoded video signal for transmission from an input digital video signal comprised of a plurality of equal-sized blocks, each of the blocks being either an inter-mode or an intra-mode video signal, said method comprising the steps of: converting each of the plurality of blocks included in the input digital video signal into a set of inter-block or intra-block DC and AC transform coefficients; selecting an intra-block DC transform coefficient from said set of inter-block or intra-block DC and AC transform coefficients; determining an intra-block DC quantizer step size for each set of a predetermined number of selected intra-block DC transform coefficients based on the selected intra-block DC transform coefficients included therein; and generating a quantized intra-block DC transform coefficient from each of the transform coefficients included in each set of the selected intra-block DC transform coefficients through the use of said intra-block DC quantizer step size.
Claim 3
Dependent Claim 13 words
The method in accordance with claim 1, wherein said predetermined number is 4.
Claim 4
Dependent Claim 84 words
The method in accordance with claim 2, wherein said intra-block DC quantizer step size is determined as 1 if the maximum value of the transform coefficients included in the set of the selected intra-block DC transform coefficients is within a range of 0 to 255; as 2, if the maximum value is within a range of 256 to 510; as 4, if it is within a range of 511 to 1020; and as 8, if it is within a ranges of 1021 to 2040.

References Cited (Backward Citations)

US4698689A Cited
US5126857A Cited
US5335016A Cited
US5323187A Cited
US5294974A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-12-04 1999-06-05 1999-12-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-12-04 2003-06-05 2003-12-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-12-04 2007-06-05 2007-12-05 $7700.00 Window Closed / Lapsed

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