The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 16, 1996
Filed:
Dec. 30, 1994
Jong-Il Kim, Incheon, KR;
Daewoo Electronics Co., Ltd., Seoul, KR;
Abstract
A novel apparatus, capable of adaptively encoding an input digital audio signal, comprises a subband filtering device for receiving the input digital audio signal and filtering the received digital audio signal, on a subband-by-subband basis; a first estimator for estimating signal-to-mask ratio data, sound pressure levels and masking thresholds for the respective subbands of the digital audio signal; a second estimator for estimating perceptual entropies for the respective frames of the input digital audio signal based on the estimated signal-to-mask ratio data, sound pressure levels and masking thresholds and for deriving a mean and a standard deviation parameters for a frame group including two or more current and previous frames which corresponds to the estimated perceptual entropies; a bit allocation unit for adaptively determining bits for each of the subbands based on the estimated signal-to-mask ratio data, perceptual entropies, and mean and standard deviation parameters and for generating bit allocation information corresponding to the determined bits for each of the subbands; a quantizer for quantizing each of the filtered subbands of the digital audio signal in response to the generated bit allocation information for each of the subbands; and a formatting circuit formatting the quantized audio signal together with the generated bit allocation information.