Patent · US Expired

Low power video decoder system with block-based motion compensation

US5978509A · kind A · utility

80Cited by
0References
36Claims
0Family size

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Key dates

Filing dateOct 22, 1997
Grant dateNov 2, 1999
Priority date
Expiry dateOct 22, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N19/61
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A battery-powered computing system (20) including video decoding capability, particularly as pertinent to the H.263 standard, is disclosed. The system (20) includes a main integrated circuit (30) having an on-chip central processing unit (CPU) (32) and on-chip shared memory (33) for the temporary buffering of video image data that is retrieved and generated during the video decoding process. The CPU (32) is programmed to perform a combined P and B prediction process (46) upon a previously predicted P frame (P.sub.T-1), with accesses to internal buffers in shared memory (33) instead of to main memory (40). Preferably, inverse transform processes (48, 52) also access shared memory (33) rather than main memory (40). The combined P and B prediction process (46) preferably handles unrestricted motion vectors using edge pixels (P.sub.edge) stored in an edge buffer (44e) in the on-chip memory (33), by modifying (58, 60) motion vector components (MVx, MVy) that point outside of the displayable video image, and retrieving the corresponding edge pixels (P.sub.edge) from the edge buffer (44e) in this event. The on-chip memory (33) preferably also includes a buffer (NEWBFR) for storing current…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.