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.

Date of Patent:
May. 05, 1998

Filed:

Nov. 29, 1995
Applicant:
Inventors:

Shigeyuki Okada, Hashima, JP;

Naoki Tanahashi, Gifu, JP;

Hayato Nakashima, Gifu-ken, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
36472503 ; 36472502 ;
Abstract

Discrete cosine transform circuits suitable for inverse discrete cosine transform (IDCT) or forward discrete cosine transform (FDCT) are disclosed. An IDCT circuit includes a group of multipliers and a group of adders/subtracters. The multipliers receive plural pieces of input data which are externally supplied in parallel. Each multiplier has a cosine constant to multiply to the received input data. The adders/subtracters receive multiplication results from the multipliers and perform addition/subtraction thereon to produce output data, which is the result of inverse discrete cosine transform of the input data. An FDCT circuit includes a group of input-stage adders/subtracters, a group of multipliers, and a group of output-stage adders. The input-stage adders/subtracters perform addition/subtraction on input data which are externally supplied in parallel. Computation results of the input-stage adders/subtracters is supplied to the multipliers. The output-stage adders receive multiplication results from the multipliers and produce output data, which is the result of forward discrete cosine transform of the input data. The discrete cosine transform circuits are particularly suitable for use in MPEG video encoders/decoders.


Find Patent Forward Citations

Loading…