ON-SCREEN COMPOSITING CIRCUIT FOR DIGITAL BROADCAST RECEIVER

• Main Author: KAWABATA YOHEI
• Format: Patent
• Language: English
• Published: 23.01.1998
• Edition: 6
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; PICTORIAL COMMUNICATION, e.g. TELEVISION

PROBLEM TO BE SOLVED: To provide an output of an on-screen composite image only at a TV monitor signal terminal without affecting a VTR output signal by compositing an analog luminance signal component of on-screen information with a luminance signal output to a TV monitor during video recording of the VTR. SOLUTION: When an on-screen display inhibit signal 1020 is active, since an AND element 1010 negates an on-screen selection signal(YS) by the on-screen display inhibit signal 1020, no YS 1030 is outputted to an on-screen compositing circuit 150. Since digital on-screen compositing is not conducted, a program signal not subject to on-screen compositing is outputted to Y, C signal outputs from a digital video encoder 16. On the other hand, a logic element 1011 provides an output of a YS signal from an on-screen generator 190 to an analog switch 2020 so as to throw the switch 2020 to the position shown in dotted lines. As a result, a luminance signal subject to on-screen compositing is outputted to a TV monitor.