US4626922A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Picture signal discriminating circuit
Assignee: Fujifilm Business Innovation Corp
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Filing: 1984-06-21
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Granted: 1986-12-02
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Expires: 2004-06-21
Abstract
Abstract A picture signal discriminating circuit, having a comparator to binary-encode an analog picture signal obtained by raster-scanning an original signal, changes the threshold level for the comparator according to the signal conditions of previously binary-encoded picture signals.
Inventors
- 👤 Hiroyuki Saitoh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:09
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/403
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
137 words
A picture signal discriminating circuit for encoding an analog picture signal which is obtained by raster-scanning picture element targets (S i ,j) in an original picture, said circuit comprising: a. a comparator for binary-encoding said analog picture signal by comparing said picture signal to a threshold level, and b. threshold level setting means for changing the threshold level of said comparator into one of a plurality of values according to previously binary-encoded values of said analog picture signal, said previously binary-encoded values corresponding to the picture elements of said original picture in the same raster immediately adjacent the target being scanned (S i ,j-1) and in the prior raster immediately adjacent the target being scanned (S i-1 ,j), and said threshold level having a maximum value determined according to a peak value of said previously binary-coded values.
Claim 2
Dependent Claim
137 words
A picture signal discriminating circuit for encoding an analog picture signal which is obtained by raster-scanning picture element targets (S i ,j) in an original picture, said circuit comprising: a. a comparator for binary-encoding said analog picture signal by comparing said picture signal to a threshold level, and b. threshold level setting means for changing the threshold level of said comparator into one of a plurality of values according to previously binary-encoded values of said analog picture signal, said previously binary-encoded values corresponding to the picture elements of said original picture in the same raster immediately adjacent the target being scanned (S i ,j-1) and in the prior raster immediately adjacent the target being scanned (S i-1 ,j), and said threshold level having a maximum value determined according to a peak value of said previously binary-coded values.
Claim 3
Dependent Claim
68 words
A picture signal discriminating in claim 1, wherein said threshold level setting means includes means for detecting the peak value of said analog picture signal; means for dividing the voltage of said peak value detecting means to obtain said comparator threshold level; and means for changing the voltage division ratio of said voltage dividing means according to the signal states previously binary-encoded values of said analog picture signal.
Claim 4
Dependent Claim
86 words
A picture signal discriminating circuit in claim 2, wherein said comparator creates a succession of binary values each corresponding to a different picture element of said original picture and wherein said threshold level setting means sets a threshold level according to the binary values of a picture element located on the same line and immediately before a picture element to be binary-encoded and a picture element which is located adjacent to and on the preceding raster scan line line as said picture element to be binary-encoded.
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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) | 1989-12-01 | 1990-06-02 | 1990-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-01 | 1994-06-02 | 1994-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-01 | 1998-06-02 | 1998-12-02 | $7700.00 | Window Closed / Lapsed |