US6415040B1
Expired / Lapsed
US
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Device for optically scanning a record carrier
Assignee: Koninklijke Philips NV
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Filing: 1998-05-20
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Granted: 2002-07-02
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Expires: 2018-05-20
Abstract
Abstract A watermark detector is disclosed to judge whether multimedia content can be copied or not. The watermark detector examines the multimedia content and outputs a signal indicating whether a watermark is present or not. A decision variable indicating to which extent the watermark is present is determined, for example, the amount of correlation between the input signal and a reference copy of the watermark to be detected. The watermark is detected if the decision variable exceeds a predetermined threshold (y 2 ). The detector also generates a random output signal for a predetermined range of decision values between the threshold (y 2 ) and a further threshold (y 1 ).
Inventors
- 👤 Johan P. M. G. Linnartz
- 👤 Maurice J. J. J-B. Maes
- 👤 Antonius A. C. M. Kalker
- 👤 Geert F. G. Depovere
- 👤 Peter M. J. Rongen
- 👤 Christianus W. F. Vriens
- 👤 Marten E. Van Dijk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:27
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/76; H04N5/91; H04N5/913; G; G06; G06T; G06T1/00; G06T1/0021; G06T1/005; G06T1/0078; H04N1/00; H04N1/32; H04N1/32101; H04N1/32144; H04N1/32149; H04N1/32203; H04N1/32208; G06T2201/00; G06T2201/005; G06T2201/0065; H04N2201/00; H04N2201/32; H04N2201/3201; H04N2201/3225; H04N2201/3233; H04N2201/3269; H04N2201/327
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
66 words
A method of detecting a watermark embedded in an information signal, comprising the steps of: determining a decision variable indicating to which extent the watermark is present in the signal; and generating an output signal indicating detection of the watermark if the decision variable exceeds a predetermined threshold (y 2 ); and randomly generating the output signal for decision values below the threshold (y 2 ).
Claim 2
Independent Claim
66 words
A method of detecting a watermark embedded in an information signal, comprising the steps of: determining a decision variable indicating to which extent the watermark is present in the signal; and generating an output signal indicating detection of the watermark if the decision variable exceeds a predetermined threshold (y 2 ); and randomly generating the output signal for decision values below the threshold (y 2 ).
Claim 3
Dependent Claim
38 words
The method as claimed in claim 1 , further comprising the step of randomly generating the output signal for a range of decision values between the threshold (y 2 ) and a further predetermined threshold (y 1 ).
Claim 4
Dependent Claim
32 words
The method as claimed in claim 1 , wherein the random output signal is generated with an increasing probability as the decision variable becomes closer to the predetermined threshold (y 2 ).
Claim 5
Dependent Claim
35 words
The method as claimed in claim 3 , wherein the probability is a linear function of the decision variable within the range between the threshold (y 2 ) and the further threshold (y 1 ).
Claim 6
Dependent Claim
36 words
The method as claimed in claim 3 , wherein the probability is a raised cosine function of the decision variable within the range between the threshold (y 2 ) and the further threshold (y 1 ).
Claim 7
Dependent Claim
30 words
The method as claimed in claim 1 , wherein the step of randomly generating the output signal includes generating the same output signal whenever the same information signal is received.
Claim 8
Dependent Claim
68 words
An arrangement for detecting a watermark embedded in an information signal, comprising: means for determining a decision variable indicating to which extent the watermark is present in the signal; and means for generating an output signal indicating detection of the watermark if the decision variable exceeds a predetermined threshold (y 2 ); means for randomly generating the output signal for decision values below the threshold (y 2 ).
Claim 9
Dependent Claim
68 words
An arrangement for detecting a watermark embedded in an information signal, comprising: means for determining a decision variable indicating to which extent the watermark is present in the signal; and means for generating an output signal indicating detection of the watermark if the decision variable exceeds a predetermined threshold (y 2 ); means for randomly generating the output signal for decision values below the threshold (y 2 ).
Claim 10
Dependent Claim
41 words
The arrangement as claimed in claim 7 , in which the arrangement further comprises means for randomly generating the output signal for a range of decision values between the threshold (y 2 ) and a further predetermined threshold (y 1 ).
Claim 11
Dependent Claim
34 words
The arrangement as claimed in claim 7 , further comprising means for generating the random output signal with an increasing probability as the decision variable becomes closer to the predetermined threshold (y 2 ).
Claim 12
Dependent Claim
42 words
The arrangement as claimed claim 9 , wherein the means for randomly generating the output signal includes a random number generator with a seed input, and means for deriving the seed input from the information signal in accordance with a predetermined function.
Claim 13
Dependent Claim
24 words
The arrangement as claimed in claim 9 , wherein the means for determining the decision variable constitute the means for deriving the seed input.
Claim 14
Dependent Claim
76 words
A multimedia playing and/or recording apparatus comprising: means for reading an information signal from and/or writing an information signal to multimedia material storage; means for determining a decision variable indicating to which extent the watermark is present in the signal; and means for generating an output signal indicating detection of the watermark if the decision variable exceeds a predetermined threshold; means for randomly generating the output signal for decision values below the threshold (y 2 ).
Claim 15
Dependent Claim
76 words
A multimedia playing and/or recording apparatus comprising: means for reading an information signal from and/or writing an information signal to multimedia material storage; means for determining a decision variable indicating to which extent the watermark is present in the signal; and means for generating an output signal indicating detection of the watermark if the decision variable exceeds a predetermined threshold; means for randomly generating the output signal for decision values below the threshold (y 2 ).
Claim 16
Dependent Claim
132 words
The method of claim 1 , in which: the output signal is randomly generated for a range of decision values between the threshold (y 2 ) and a further predetermined threshold (y 1 ); the random output signal is generated with an increasing probability as the decision variable becomes closer to the predetermined threshold (y 2 ); the probability is a linear function of the decision variable within the range between the threshold (y 2 ) and the further threshold (y 1 ); the probability is a raised cosine function of the decision variable within the range between the threshold (y 2 ) and the further threshold (y 1 ); and the step of randomly generating the output signal includes generating the same output signal whenever the same information signal is received.
Claim 17
Dependent Claim
113 words
The arrangement of claim 7 , in which: the arrangement further comprises means for randomly generating the output signal for a range of decision values between the threshold (y 2 ) and a further predetermined threshold (y 1 ); means for generating the random output signal with an increasing probability as the decision variable becomes closer to the predetermined threshold (y 2 ); the means for randomly generating the output signal includes a random number generator with a seed input, and means for deriving the seed input from the information signal in accordance with a predetermined function; and the means for determining the decision variable constitute the means for deriving the seed input.
References Cited (Backward Citations)
US6128401A
Cited
US5606609A
Cited
WO1996036163A2
Cited
US5748783A
Cited
EP0766468A2
Cited
WO1997013248A1
Cited
US6131161A
Cited
US5933798A
Cited
US6226387B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2005-07-01 | 2005-12-31 | 2006-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-07-01 | 2009-12-31 | 2010-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-07-01 | 2013-12-31 | 2014-07-02 | $7700.00 | Window Closed / Lapsed |