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:
Sep. 18, 2001
Filed:
Jan. 28, 1999
Masaru Matsui, Gifu, JP;
Sanyo Electric Co., Ltd., , JP;
Abstract
To achieve bi-directional transformation by using a single simply-structured discrete cosine transformation circuit for use in an audio recording/reproducing device. There is provided a circuit which comprises a RAM,, a ROM,, a multiplier,, and an adder/subtracter,and is capable of performing inverted transformation of a discrete cosine transformation. The multiplier,multiplies operand data stored in the RAM,by a proportional coefficient stored in the ROM,. The adder/subtracter,add/subtracts outputs of the multiplier,. This circuit is also able to perform a characteristic operation in a forward direction, such as addition or subtraction using intact base data. Specifically, data before conversion is stored in the RAM,, and one of them is supplied to the adder/subtracter,via an input terminal A. The supplied base data is added to the value “0” which is supplied to the adder/subtracter,via the input terminal B by the selector,, whereby the base data is passed intact through the adder/subtracter,. The outputted base data is then fed to the adder/subtracter,via the input terminal B by means of loop back through the selector,, and added or subtracted with respect to another base data item which is supplied to the adder/subtracter,via the input terminal A.