US4989246A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Adaptive differential, pulse code modulation sound generator
Assignee: Industrial Technology Research Institute
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Filing: 1989-03-22
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Granted: 1991-01-29
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Expires: 2009-03-22
Abstract
Abstract A sound generator for storing and reproducing audio signal with reduced memory storage, which is accomplished by: (a) the technique of Adaptive Differential Pulse Code Modulation (ADPCM), and (B) the elimination of silence period from memory storage but regenerating the silence signal at output.
Inventors
- 👤 Shyue-Yun Wan
- 👤 Shie-Ming Peng
- 👤 Der-Chwan Wu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:21
CPC Classifications
H; H03; H03M; H03M7/00; H03M7/30; H03M7/3002; H03M7/3044; H03M7/3046; G; G10; G10L; G10L19/00; G10L19/012
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
218 words
A storage and generation system for sound signal having silence and repetition periods, comprising means for converting said sound signal into digital codes using adaptive differential pulse code modulation (ADPCM) technique, means for storing in a memory said digital codes except said silence periods and repetition periods, means for converting said stored digital codes into analog signal together with said silence period and repetition periods, means for converting said ADPCM code in a read only memory based on different signal content, said means for storing said ADPCM code and said means for converting said digital signals including: (a) Oscillator for generating a basic clock pulse for whole said system, (b) Timing generator for generating clocks for different functional blocks, (c) Control circuit for controlling the start, repetition and end of said sound signal, (d) ROM1 for storing said sound signal codes, Address Decoder for outputting decoded addresses from said ROM1, (f) Data Decoder for decoding said digital codes from said ROM1, (g) ROM2 for storing stepsize values, (h) ADDER1 for adding or subtracting data from said decoder and outputting results to addresses of said ROM2, (i) ADDER2 for adding or subtracting said size values, (j) Data Code Counter for controlling said ADDER2 for continuous addition, (k) DAC for transferring the signal from said ADDER2 to corresponding analog signal.
Claim 2
Dependent Claim
218 words
A storage and generation system for sound signal having silence and repetition periods, comprising means for converting said sound signal into digital codes using adaptive differential pulse code modulation (ADPCM) technique, means for storing in a memory said digital codes except said silence periods and repetition periods, means for converting said stored digital codes into analog signal together with said silence period and repetition periods, means for converting said ADPCM code in a read only memory based on different signal content, said means for storing said ADPCM code and said means for converting said digital signals including: (a) Oscillator for generating a basic clock pulse for whole said system, (b) Timing generator for generating clocks for different functional blocks, (c) Control circuit for controlling the start, repetition and end of said sound signal, (d) ROM1 for storing said sound signal codes, Address Decoder for outputting decoded addresses from said ROM1, (f) Data Decoder for decoding said digital codes from said ROM1, (g) ROM2 for storing stepsize values, (h) ADDER1 for adding or subtracting data from said decoder and outputting results to addresses of said ROM2, (i) ADDER2 for adding or subtracting said size values, (j) Data Code Counter for controlling said ADDER2 for continuous addition, (k) DAC for transferring the signal from said ADDER2 to corresponding analog signal.
Claim 3
Dependent Claim
39 words
A storage and generating system for sound having silence and repetition periods as described in claim 1, wherein said Address Decoder and said ROM1 can automatically generate a signal such as 0000 which is decoded by said address decoder.
Claim 4
Dependent Claim
26 words
The claim 1 storage and generating system for sound having silence and repetition periods wherein said ADDER 2 adds a digital signal, such as 0000, appears.
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) | 1994-01-28 | 1994-07-30 | 1995-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-28 | 1998-07-30 | 1999-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-28 | 2002-07-30 | 2003-01-29 | $7700.00 | Window Closed / Lapsed |