Method and device for film-mode detection

US5365273A · kind A · utility

Assignee

• Deutsche Thomson-Brandt GmbH · DE

Inventors

• Carlos Correa · Villingen-Schwenningen, DE
• Rainer Schweer · Mengen, DE

Key dates

• Filing date: Apr 23, 1993
• Grant date: Nov 15, 1994
• Expiry date: Apr 23, 2013

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04N9/11
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

A film mode detection method and corresponding relatively non complex hardware implementation compares the amplitudes of pixels of corresponding image areas of three successive field to determine if the pixel amplitudes are monotonically increasing or decreasing. Depending on the comparison a positive or negative polarity indication is generated and these indications are combined within each field to generate a polarity indication representing each respective field. The field sequence of such field polarity indications are thereafter compared with a predetermined pattern to determine whether the video signal is from a film or video-mode source.