US5016104A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Receiver-compatible noise reduction systems
Assignee: Massachusetts Institute of Technology
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Filing: 1989-06-22
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Granted: 1991-05-14
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Expires: 2009-06-22
Abstract
Abstract Method and systems for combatting degradation in the transmission or storage of data signals especially useful in the field of motion picture or television signal transmission, such that an advanced receiver can decode that information to provide improved picture quality, while a standard receiver will display an image with minimally visible impairments. A data signal can be decomposed into a low frequency signal and a high frequency signal, and that the high frequency signal can then be modified by the application of a series of scaling factors over selected regions in response to local variance of data values in such regions. The low frequency signal and the modified high frequency signal are then combined and transmitted (or recorded) as a modulated facsimile of the data signal, together with the scaling factors. In the advanced receiver (or playback unit), the data signal is reconstructed from the modulated facsimile with concommittant reduction in signal degradation by the application of a series of inverse scaling factors.
Inventors
- 👤 Jae S. Lim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:01
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/015; H04N5/00; H04N5/14; H04N5/21; H04N7/12; H04N7/127; H04N19/00; H04N19/30
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
145 words
An apparatus for combatting degradation of data signals, the apparatus comprising: decomposition means for decomposing a data signal into a low frequency signal and at least one high frequency signal; variance measurement means for measuring the local variance of data values in said high frequency signal; scaling means for modifying the high frequency signal by application of a series of scaling factors over selected regions in response to the local variance of data values in said regions to produce a modified high frequency signal; summing means for summing said low frequency signal and said modified high frequency signal to yield a modulated facsimile of the data signal, and means for transmitting or storing said modulated facsimile and data representative of said scaling factors to permit reconstruction of the data signal and concomitant reduction in signal degradation by application of a series of inverse scaling factors.
Claim 2
Independent Claim
145 words
An apparatus for combatting degradation of data signals, the apparatus comprising: decomposition means for decomposing a data signal into a low frequency signal and at least one high frequency signal; variance measurement means for measuring the local variance of data values in said high frequency signal; scaling means for modifying the high frequency signal by application of a series of scaling factors over selected regions in response to the local variance of data values in said regions to produce a modified high frequency signal; summing means for summing said low frequency signal and said modified high frequency signal to yield a modulated facsimile of the data signal, and means for transmitting or storing said modulated facsimile and data representative of said scaling factors to permit reconstruction of the data signal and concomitant reduction in signal degradation by application of a series of inverse scaling factors.
Claim 3
Dependent Claim
49 words
The apparatus of claim 1 wherein the decomposition means further comprises a low pass filtering means for filtering said data signal to obtain the low frequency signal and a computation means for deriving the high frequency signal by subtraction of said low frequency signal from the unfiltered data signal.
Claim 4
Dependent Claim
43 words
The apparatus of claim 1 wherein the scaling means further includes means for calculating said scaling factors based on the dynamic range of said high and low frequency signals, as well as the local variance of data values in the high frequency signal.
Claim 5
Dependent Claim
35 words
The apparatus of claim 1 wherein the apparatus further includes an amplitude modifying means for compressing the dynamic range of said low frequency signal prior to construction of the modulated facsimile of the data signal.
Claim 6
Dependent Claim
44 words
The apparatus of claim 1 wherein the apparatus further includes means for sampling and quantizing said low frequency signal, and means for transmitting or storing data representative of the sampled, quantized low frequency signal, together with said modulated facsimile and said scaling factor data.
Claim 7
Dependent Claim
13 words
The apparatus of claim 1 wherein the data signal comprises television luminance values.
Claim 8
Independent Claim
126 words
A method of combating degradation of data signals, a method comprising the steps of: composing a data signal into a low frequency signal and at least one high frequency signal; measuring the local variance of data values in such high frequency signal; modifying the high frequency signal by application of a series of scaling factors over selected regions in response to the local variance of data values in certain regions to produce a modified high frequency signal; and summing said low frequency signal and said modified high frequency signal yield a modulated facsimile of the data signal, such that said modulated facsimile can be used to reconstruct the data signal with a concomitant reduction in signal degradation by application of a series of inverse scaling factors.
Claim 9
Independent Claim
126 words
A method of combating degradation of data signals, a method comprising the steps of: composing a data signal into a low frequency signal and at least one high frequency signal; measuring the local variance of data values in such high frequency signal; modifying the high frequency signal by application of a series of scaling factors over selected regions in response to the local variance of data values in certain regions to produce a modified high frequency signal; and summing said low frequency signal and said modified high frequency signal yield a modulated facsimile of the data signal, such that said modulated facsimile can be used to reconstruct the data signal with a concomitant reduction in signal degradation by application of a series of inverse scaling factors.
Claim 10
Dependent Claim
42 words
The method of claim 7 wherein the step of decomposing the data signal further comprises filtering said data signal to obtain said low frequency signal and deriving the high frequency signal by subtracting said low frequency signal from the unfiltered data signal.
Claim 11
Dependent Claim
46 words
The method of claim 7 wherein the step of modifying the high frequency signal further includes calculating said scaling factors based on the dynamic range of said high and low frequency signals, as well as the local variance of data values in the high frequency signal.
Claim 12
Dependent Claim
26 words
The method of claim 7 wherein the method further includes compressing the dynamic range of said low frequency signal prior to construction of the modulated facsimile.
Claim 13
Dependent Claim
16 words
The method of claim 7 wherein the method further includes transmitting or storing said modulated facsimile.
Claim 14
Dependent Claim
34 words
The method of claim 11 wherein the method further includes transmitting or storing data representative of said scaling factors and a subsampled, quantized version of the low frequency signal, together with said modulated facsimile.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-05-13 | 1994-11-12 | 1995-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-13 | 1998-11-12 | 1999-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-13 | 2002-11-12 | 2003-05-14 | $7700.00 | Window Closed / Lapsed |