Title:
GHOST DETECTION CIRCUIT
Document Type and Number:
Japanese Patent JPH02250467
Kind Code:
A
Abstract:
PURPOSE:To make ghost detection stable by selecting either output signal of the output signals of 1st and 2nd ghost cancellation reference signal (GCR) signal extraction pulse generating circuits for ghost elimination so as to check whether or not a vertical synchronizing signal separator circuit of a television signal is correctly operated. CONSTITUTION:When a pulse to fetch a GCR signal is generated by using 4fsc, it cannot cope with the case with occurrence of a discontinuous vertical synchronizing signal caused at the changeover of a camera. Then a vertical synchronizing confirmation circuit 119 monitors the discontinuity of the vertical synchronizing signal and when discontinuity takes place, a 1st GCR signal extraction pulse generating circuit 116 is used to generate again a GCR signal extraction pulse at a normal position and then a 2nd GCR signal extraction pulse generating circuit 116 is used to generate the GCR signal extraction pulse. Thus, the system copes with even the discontinuity of the vertical synchronizing signal to detect ghost stably at all times.
Inventors:
OZAWA TOSHIMITSU
INMI MASABUMI
ITO SHIGEFUMI
KIMURA KATSUNOBU
SHIBUYA HIROSHI
INMI MASABUMI
ITO SHIGEFUMI
KIMURA KATSUNOBU
SHIBUYA HIROSHI
Application Number:
JP7067289A
Publication Date:
October 08, 1990
Filing Date:
March 24, 1989
Export Citation:
Assignee:
HITACHI LTD
HITACHI VIDEO ENG
HITACHI VIDEO ENG
International Classes:
H04N5/21; H03H17/00; H03H17/08; (IPC1-7): H03H17/08; H04N5/21
Attorney, Agent or Firm:
Katsuo Ogawa (1 person outside)