Patent · US Expired

Image data compression

US5995149A · kind A · utility

11Cited by
5References
20Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJul 31, 1997
Grant dateNov 30, 1999
Priority date
Expiry dateJul 31, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N19/146
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Image data compression apparatus comprises a data compressor for receiving data representing sub-areas of an input image and for generating respective blocks of compressed data representing those sub-areas, each block of compressed data comprising at least low spatial frequency image data and higher spatial frequency image data; a data formatter for formatting predetermined groups of said blocks of compressed data into output data blocks, said data formatter having a predetermined data capacity; a detector for detecting whether a current group of said blocks of compressed data contains more data than said data capacity of said data formatter; and a block truncator, responsive to a detection that a current group of said blocks of compressed data contains more data than said data capacity of said data formatter, for truncating one or more of said blocks of compressed data by discarding at least said higher spatial frequency image data.

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