Patent · US Expired

Facsimile system for the transmission of picture

US3956578A · kind A · utility

7Cited by
5References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 27, 1974
Grant dateMay 11, 1976
Priority date
Expiry dateDec 27, 1994

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/411
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

This system is provided for the field of electronic facsimile transmitting of a picture and relates more particularly to the compression of data to reduce the number of bits to be transmitted at a given resolution of the picture. Compression is effected by a correlation of neighbouring points of the picture by omitting, at the transmitting end, one point in four on two adjacent lines and by restituting it at the receiving end by means of a relatively simple Boolean function which takes into account the structure of the characters used in that picture. That first compression may be combined with a second compression due to the coding of the length of a white range.

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