Patent · US Expired

Digital video signal processing apparatus for providing zoom and compressive images with soft focus

US4682227A · kind A · utility

6Cited by
4References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 8, 1985
Grant dateJul 21, 1987
Priority date
Expiry dateApr 8, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/64
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A video signal processing apparatus comprises an input (1) for receiving an input video signal and an output (2) at which the processed signal is produced. The apparatus includes a vertical filter (3), a horizontal filter (4), a vertical interpolator (5) a horizontal interpolator (6), and a field store (7) arranged in cascade. The cut-off frequencies of the vertical and horizontal filters (3,4) are adjustable by means of signals passed over paths (18 and 19) from the control circuit (8) to the filters (3,4). A control apparatus comprising a potentiometer (25), a switch (23), and an analogue to digital converter (26) produces signals which are passed over a path (24) to the control circuit (8). These signals are used to cause the control circuit (8) to produce signals over paths (18,19) to the filters (3,4) which reduce the cut-off frequencies of the filters to a value which is below that appropriate to the picture size. This produces a soft focus effect.

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