US5305102A
Expired / Lapsed
US
⏱️ 0.0 years remaining
HDTV receiver
Assignee: Nokia Bell Labs
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Filing: 1992-07-27
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Granted: 1994-04-19
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Expires: 2012-07-27
Abstract
Abstract The effects of perturbations in a decoder responsive to a signal encoded in a predictive coding schema are reduced by shortening the time needed to converge the decoder's prediction signal to that of the encoder. This is accomplished by temporarily altering the leak factor when it is known that a perturbation is about to manifest itself and by, in some situations, altering the incoming encoded signal itself.
Inventors
- 👤 Scott C. Knaur
- 👤 Kim N. Matthews
- 👤 Arun N. Netravali
- 👤 Eric D. Petajan
- 👤 Robert J. Safranek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:16
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/24; H04N7/52; H04N7/54; H04N19/00; H04N19/10; H04N19/134; H04N19/146; H04N19/152; H04N19/60; H04N19/61; H04N19/85; H04N19/89; H04N19/50
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
106 words
A decoder including means for receiving incoming signals and developing therefrom displaced frame difference signals and leak factor signals, an adder for combining signals related to the displaced frame difference signals with prediction signals, a buffer for storing signals responsive to the adder, and means for altering signals outputted by the buffer in response to the leak factor signals to develop thereby the prediction signals, wherein the improvement comprises: error detection means for developing an error signal that identifies errors in the displaced frame difference signals, and first means for modifying the leak factor signals applied to the means for altering based on the error signal.
Claim 2
Dependent Claim
106 words
A decoder including means for receiving incoming signals and developing therefrom displaced frame difference signals and leak factor signals, an adder for combining signals related to the displaced frame difference signals with prediction signals, a buffer for storing signals responsive to the adder, and means for altering signals outputted by the buffer in response to the leak factor signals to develop thereby the prediction signals, wherein the improvement comprises: error detection means for developing an error signal that identifies errors in the displaced frame difference signals, and first means for modifying the leak factor signals applied to the means for altering based on the error signal.
Claim 3
Dependent Claim
79 words
The decoder of claim 1 wherein the means for receiving also develops motion vector signals, the buffer includes MV means for altering the output signals of the buffer under control of the motion vector signals, the error detection means includes means for identifying errors in the motion vector signals; and the MV means includes a buffer for storing motion vectors and for selecting stored or unstored motion vectors to control the altering of the output signals of the buffer.
Claim 4
Dependent Claim
24 words
The decoder of claim 1 further comprising means for altering the leak signal in response to a channel change signal applied to the decoder.
Claim 5
Dependent Claim
32 words
The decoder of claim 1 further comprising means for altering the leak signal in response to a channel change signal that is unrelated to the signal applied to the means for receiving.
Claim 6
Dependent Claim
29 words
The decoder of claim 4 further comprising second means for modifying, interposed before the adder, for changing the displaced frame difference signals in response to the channel change signal.
Claim 7
Dependent Claim
20 words
The decoder of claim 5 wherein the second means for modifying is also responsive to the received leak factor signals.
Claim 8
Dependent Claim
78 words
The decoder of claim 6 wherein the incoming signals arrive in frame segments and, in response to the channel change signal, when the leak factor signal is other than equal to 1, the first means for modifying changes the leak factor signal applied to the means for altering to 0 for one frame and the second means for modifying multiplies the displaced frame difference signals by 1/(1-α) during that one frame, where α is the leak factor signal.
Claim 9
Dependent Claim
65 words
The decoder of claim 7 where, whenever the second means for modifying multiplies the displaced frame difference signals by 1/(1-α) during one frame, it also multiplies the displaced frame difference signals by a smaller multiplier during the frame following the one frame, provided that smaller multiplier is not smaller than 1/(1-α'), where α' is the leak factor signal of the frame following the one frame.
Claim 10
Dependent Claim
152 words
Apparatus responsive to an input signal that includes displaced frame difference data signals and a buffer control signal, comprising: an input buffer for storing the input signal, means for determining the fullness level of the input buffer, A decoder responsive to signals stored in the input buffer, means for evaluating the fullness level of the input buffer with reference to the buffer control signal to develop a comparison signal; means for taking action A, B, or C in response to the comparison signal, where action A is applying at least a subset of the signals stored in the input buffer to the decoder, action B is re-applying at least a subset of the signals stored in the input buffer to the decoder, and action C is skipping over a subset of the signals stored in the input buffer and sending another subset of signals stored in the input buffer to the decoder.
Claim 11
Dependent Claim
152 words
Apparatus responsive to an input signal that includes displaced frame difference data signals and a buffer control signal, comprising: an input buffer for storing the input signal, means for determining the fullness level of the input buffer, A decoder responsive to signals stored in the input buffer, means for evaluating the fullness level of the input buffer with reference to the buffer control signal to develop a comparison signal; means for taking action A, B, or C in response to the comparison signal, where action A is applying at least a subset of the signals stored in the input buffer to the decoder, action B is re-applying at least a subset of the signals stored in the input buffer to the decoder, and action C is skipping over a subset of the signals stored in the input buffer and sending another subset of signals stored in the input buffer to the decoder.
Claim 12
Dependent Claim
48 words
The apparatus of claim 9 wherein the input signal arrives in frame segments of non-uniform length and the buffer control signal is a number of frames and the means for evaluating the fullness level of the input buffer determines the number of frames stored in the input buffer.
References Cited (Backward Citations)
US5134477A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-04-18 | 1997-10-18 | 1998-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-04-18 | 2001-10-18 | 2002-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-04-18 | 2005-10-18 | 2006-04-19 | $7700.00 | Window Closed / Lapsed |