Patent · US Expired

Font recall system and method of operation

US4568981A · kind A · utility

28Cited by
5References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 8, 1983
Grant dateFeb 4, 1986
Priority date
Expiry dateApr 8, 2003

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/278
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A font recall system stores a font of alpha-numeric characters in a video display format for selective insertion as a caption into a video image. Characters are stored on a video disk in digital pixel form with full dynamic resolution. Low pass filtering is employed to preserve high image quality and eliminate jagged edge aliasing at character boundaries. A first frame store receives selected characters from the video disk through an image size reducer to store the characters at selected display positions with a selected size to form a caption under control of a central processing unit. A keyer receives the caption video data from the first frame store as well as a background image to form a composite image, which is stored in the second frame store before being output as a continuous television video signal.

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