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. 15, 1998
Filed:
Apr. 18, 1995
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
An video decoder system, such as for use with MPEG video compression, uses a previous B-frame as an additional prediction source for the current B-frame. In one embodiment, a given block within a current B-frame 'N' reuses IDCT result terms from the previous B-frame 'N-1' if they are determined to be 'similar enough' to the anticipated IDCT result terms which would otherwise need to be computed. For a given block, each of the 'M' lowest-frequency DCT coefficients for B-frame 'N' and B-frame 'N-1' are respectively compared: if they differ by less than a similarity threshold value, then the IDCT result terms from the previous B-frame 'N-1' are reused without further computation. The similarity threshold may be adaptively adjusted to reduce the computational burden of video decompression, while affording a gradual degradation of picture quality, rather than wholesale skipping of entire frames.