EP0564089A1
Expired / Lapsed
EP
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A method and appartus for the perceptual coding of audio signals
Assignee: AT&T Inc
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Filing: 1993-02-25
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Granted: —
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Expires: 2013-02-25
Abstract
Abstract A method and apparatus for performing a Modified Discrete Cosine Transform on an audio signal is disclosed which utilizes a Discrete Fourier Transform. Illustratively, the MDCT spectral coefficients for the signal are generated from the real FFT spectral coefficients.
Inventors
- 👤 Anibal Joao De Sousa Ferreira
- 👤 James David Johnston
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 17:50
CPC Classifications
G; G11; G11B; G11B20/00; H; H04; H04H; H04H20/00; H04H20/86; H04H20/88; G11B20/00007; H04B; H04B1/00; H04B1/66; H04B1/665; G11B20/10; G11B20/10527; G11B2020/10537; G11B2020/10592
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
87 words
A method of coding a digital input signal to provide a coded digital output signal, the method comprising the steps of: sampling the digital input signal to create a frame of 2N input signal samples; analyzing the frame of signal samples with an odd-frequency fast Fourier transform to provide a frame of 2N Fourier coefficients; and outputting a coded signal comprising samples X(k), each sample X(k) provided by multiplying the real part of a Fourier coefficient, F(k), by cos[ π(2k + 1)(1 + N) 4N ] .
References Cited (Backward Citations)
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