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:
Aug. 28, 2007
Filed:
May. 02, 2003
Toshiharu Kuwaoka, Yokohama, JP;
Toshiharu Kuwaoka, Yokohama, JP;
Victor Company if Japan, Ltd., Yokohama, JP;
Abstract
A digital audio signal has a sequence of samples. Extreme values in an audio waveform represented by the digital audio signal are detected. The extreme values include a maximum value and a minimum value. An audio frequency represented by the digital audio signal is detected in response to the number of samples between two temporally-adjacent extreme-corresponding samples. A difference between each extreme value and a value of a sample which immediately precedes the present extreme-corresponding sample is calculated. The calculated differences are multiplied by selected one of predetermined coefficients to get corrective values respectively. A decision is made as to whether or not the detected audio frequency is in one selected from predetermined frequency bands. When the detected audio frequency is in the selected frequency band, a corresponding corrective value is added to the maximum value and a corresponding corrective value is subtracted from the minimum value.