US4682230A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Adaptive median filter system
Assignee: RCA Licensing Corp
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Filing: 1986-03-21
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Granted: 1987-07-21
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Expires: 2006-03-21
Abstract
Abstract An adaptive median filter system is disclosed. Circuitry is arranged to produce successive sets of samples from an input signal which may possibly include noise. An adaptive median filter filters the samples in response to a control signal. Further circuitry estimates the relative density of the noise in the input signal to generate the control signal supplied to the adaptive median filter.
Inventors
- 👤 Stuart S. Perlman
- 👤 Sanford Eisenhandler
- 👤 Paul W. Lyons
- 👤 Michael J. Shumila
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:03
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/21; G; G06; G06T; G06T5/00; G06T5/20; G06T5/70; G06T2207/00; G06T2207/20; G06T2207/20004; G06T2207/20012; G06T2207/20024; G06T2207/20032
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
69 words
An adaptive median filter system, comprising: a source of an input signal possibly including noise; means responsive to said input signal for producing successive sets of samples representing said input signal; means for adaptively median filtering said samples responsive to control signal; means responsive to said input signal for estimating the relative density of said noise; and means responsive to said estimated noise density for generating said control signal.
Claim 2
Dependent Claim
69 words
An adaptive median filter system, comprising: a source of an input signal possibly including noise; means responsive to said input signal for producing successive sets of samples representing said input signal; means for adaptively median filtering said samples responsive to control signal; means responsive to said input signal for estimating the relative density of said noise; and means responsive to said estimated noise density for generating said control signal.
Claim 3
Dependent Claim
80 words
The system of claim 1, wherein said adaptive median filter means comprises: means for determining a median value sample and upper and lower M-tile value samples of said set of samples; means responsive to further control signal for selectively substituting said median value sample for a current one of said set of samples being filtered; and means responsive to said median valued sampled, said upper and lower M-tile value samples, and said current sample for generating said further control signal.
Claim 4
Dependent Claim
92 words
The system of claim 2, wherein said further control signal generator comprises: first subtracting means responsive to said upper and lower M-tile value samples for producing the difference therebetween; second subtacting means responsive to said current sample and said median value sample for producing the difference therebetween; and comparing means coupled to said first and second subtracting means for comparing the differences from said first and second subtracting means and for producing said further control signal if the difference from said second subtracting means exceeds the difference from said first subtracting means.
Claim 5
Dependent Claim
25 words
The system of claim 3 wherein said further control signal generator includes: a function generator coupled between said first subtracting means and said comparing means.
Claim 6
Dependent Claim
30 words
The system of claim 4 wherein said function generator includes means for multiplying a signal input to said function generator by a first constant and adding a second non-zero constant.
Claim 7
Dependent Claim
118 words
The system of claim 2, wherein said median value and upper and lower M-tile value sample producer comprises: means having a plurality of input terminals responsive to said set of samples, and a plurality of output terminals for producing said set of samples ordered according to their values; and multiplexing means having respective data input terminals responsive to said ordered set of samples, data output terminals for producing at least said upper and lower M-tile value samples, and a control input terminal responsive to said control signal, for coupling respective selected ones of said ordered set of samples to said upper and lower M-tile value sample data output terminals in response to the value of said control signal.
Claim 8
Dependent Claim
89 words
An adaptive median filter system comprising: a source of an input signal possibly including noise; means responsive to said input signal for producing successive sets of samples representing said input signal; means for adaptively median filtering said samples responsive to a control signal and producing a signal indicating that a current one of said set of samples represents a relatively noisy signal; means responsive to said indicating signal for estimating the relative density of said noise; and means responsive to said estimated noise density for generating said control signal.
Claim 9
Dependent Claim
89 words
An adaptive median filter system comprising: a source of an input signal possibly including noise; means responsive to said input signal for producing successive sets of samples representing said input signal; means for adaptively median filtering said samples responsive to a control signal and producing a signal indicating that a current one of said set of samples represents a relatively noisy signal; means responsive to said indicating signal for estimating the relative density of said noise; and means responsive to said estimated noise density for generating said control signal.
Claim 10
Dependent Claim
107 words
An adaptive median filter system, comprising: a source of an input signal including alternating synchronization and information time intervals and possibly including noise; means responsive to said input signal for producing successive sets of samples representing said input signal; means for adaptively median filtering said samples responsive to a control signal during said information time interval and producing a signal indicating that a current one of said set of samples represents a relatively noisy signal during said synchronization time interval; means responsive to said indicating signal for estimating the relative density of said noise; and means responsive to said estimated noise density for generating said control signal.
Claim 11
Dependent Claim
107 words
An adaptive median filter system, comprising: a source of an input signal including alternating synchronization and information time intervals and possibly including noise; means responsive to said input signal for producing successive sets of samples representing said input signal; means for adaptively median filtering said samples responsive to a control signal during said information time interval and producing a signal indicating that a current one of said set of samples represents a relatively noisy signal during said synchronization time interval; means responsive to said indicating signal for estimating the relative density of said noise; and means responsive to said estimated noise density for generating said control signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-07-20 | 1991-01-19 | 1991-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-20 | 1995-01-19 | 1995-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-20 | 1999-01-19 | 1999-07-21 | $7700.00 | Window Closed / Lapsed |