Title:
TECHNIQUE FOR APPLYING COMPATIBILITY BETWEEN HIGH-DEFINITION COLOR TELEVISION AND CONVENTIONAL-TYPE COLOR TELEVISION
Document Type and Number:
Japanese Patent JPH05284507
Kind Code:
A
Abstract:
PURPOSE: To attain compatibility between a high-definition color TV and a conventional system color TV by generating a high-definition color TV image signal through frequency scale-up of the conventional TV system and enabling conversion into a compatible high-definition color TV image signal. CONSTITUTION: Signals R, G and B are sent from a camera by a line-scanning signal FR and sent to a matrix circuit 10 of luminance Y and chrominance signals I and Q. Prescribed band widths BI and BQ are applied to the chrominance signals I and Q by LPFs 16 and 17, the signals I and Q are added 20 to the luminance signal Y after square modulation 18 and 19 on color subcarrier waves. Then, the LPF of composite high-definition HDTV signal to the suitable band width BL is performed by a filter 21. Further, a color subcarrier frequency Fc is applied by a generator 22 for generating the color subcarrier frequency to be used for the NTSC system. Since a required higher harmonic wave, such as the HDTV composite signal is applied to the color subcarrier frequency, for example by a circuit 23 for making the output signal of generator 22 large by 18/5-fold, the output is converted into a suitable color subcarrier frequency.
Inventors:
Haskell, Baling the Offray
Application Number:
JP31286291A
Publication Date:
October 29, 1993
Filing Date:
November 28, 1991
Export Citation:
Assignee:
Western Electric Campany, Inc.
International Classes:
H04N5/46; H04N7/01; H04N7/015; H04N7/06; H04N9/00; H04N11/20; H04N11/24; (IPC1-7): H04N9/00; H04N5/46
Attorney, Agent or Firm:
Masao Okabe