Patent · US Expired

Letterbox image detection apparatus

US6208385A · kind A · utility

35Cited by
1References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 17, 1997
Grant dateMar 27, 2001
Priority date
Expiry dateOct 17, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S348/913
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A letterbox image detection apparatus for detecting a letterbox image by detecting a boundary of an image area and a non-image area, so as to display the image area on a full screen according to the detection result but not to display the non-image area. The apparatus includes timing pulse generator for generating a timing pulse for splitting one screen image into N columns (N is an integer of 2 or more), image property calculator for calculating the image property of the N horizontal sections (hereinafter referred to as columns) split by the timing pulse generator, inter-line difference calculator for calculating the inter-line difference of the N image properties, edge detector for comparing the inter-line difference with a predetermined upper first threshold th1 and for detecting the edge, and edge position data holder for holding the vertical position data of the in-column edge detected by the edge determinator.

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