JPH04267694A - Television receiver - Google Patents

Abstract

PURPOSE:To convert an NTSC luminance signal Y and color difference signals B-Y, R-Y into an HDTV luminance signal YHD and color difference signals PB, PR to implement color reproduction with fidelity in which a difference with the High Vision is not recognized at the display of the NTSC color difference input video image in the signal processing circuit of the High Vision HDTV. CONSTITUTION:In order to use an HDTV signal processing circuit in common even at NTSC signal input, a matrix circuit 13 is realized, which is provided with inverters 2, 6 converting NTSC signals Y, B-Y, R-Y into HDTV signals YHD, PB, OR, coefficient devices 1, 3, 4, 5, 7, 8, 9 having a prescribed coefficient and adders 10, 11, 12.

Description

[Detailed description of the invention]

0001

FIELD OF INDUSTRIAL APPLICATION This invention relates to a high-definition color difference signal conversion circuit for NTSC color difference signals in video signal processing circuits of high-definition receivers, high-definition monitors, and the like.

0002

[Prior art] In high-definition HDTV, NTSC
NTSC luminance signal Y and HDTV luminance signal YHD because the three reference primary colors are different when displaying a color difference input video
There are differences in color reproduction due to differences in transmission signal equations. That is, for the equation Y=0.30R+0.59G+0.11B of the NTSC luminance signal Y, H
The equation of DTV brightness signal YHD is YHD=0.212
This is because R+0.701 G+0.087 B is different. Furthermore, since the HDTV signal processes the color difference signals as PB and PR, a separate dedicated processing circuit is required to process the NTSC color difference signals BY and RY, which increases the circuit scale.

0003

SUMMARY OF THE INVENTION The present invention has been made in view of the above conventional example, and provides an NTSC luminance signal for faithful color reproduction with no discernible difference from high-definition HDTV when displaying NTSC color difference input video. Y and color difference signal B
The present invention provides a cost-effective conversion circuit for converting -Y and RY into an HDTV luminance signal YHD and color difference signals PB and PR.

0004

[Means for Solving the Problems] The present invention uses a high-vision HDTV signal processing circuit in common even when inputting NTSC signals.
-Y to HDTV signals YHD, PB, PR, a coefficient multiplier having predetermined coefficients, and an adder for the output of the coefficient multiplier.

[0005]

[Operation] As shown in FIG. 1, a matrix circuit includes inverters 2 and 6, coefficient multipliers 1, 3, 4, 5, 7, 8, and 9 having predetermined coefficients, and adders 10, 11, and 12 for the coefficient multiplier outputs. 13
NTSC luminance signal Y and color difference signal B-Y,
It inputs RY, adds a predetermined coefficient output, and outputs a high-definition luminance signal YHD and color difference signals PB and PR.

[0006]

[Example] In Fig. 1, 1 is a coefficient unit with a coefficient value of 1 which receives the NTSC luminance signal Y as input, 2 is an inverter with an NTSC color difference signal B-Y, and 3 and 4 each receives the B-Y with a coefficient value of 0.
．． 572 and 0.028 coefficients, 5 is -(B-
6 is an inverter for the color difference signal R-Y, 7 and 8 are coefficient multipliers with coefficient values 0.079 and 0.726, respectively, which receive R-Y as input; 9 is a coefficient value of 0.144 with -(RY) as input
Coefficient machine, 10 is Y of coefficient machine 1 output and -0.044 of coefficient machine 5 output, coefficient B-Y and -0.14 of coefficient machine 9 output.
4 an adder that adds the coefficients RY and outputs the high-definition HDTV brightness signal YHD; 11 is the 0.
572 An adder that adds the coefficient B-Y and the 0.079 coefficient R-Y of the coefficient unit 7 output and outputs the HDTV color difference signal PB. 12 is the 0.028 coefficient B-Y of the coefficient unit 4 output and the coefficient unit 8. Add the output 0.726 coefficient RY and HD
This is an adder that outputs a TV color difference signal PR.

[0007] The coefficient values of each coefficient unit for conversion into an HDTV color difference signal are set as follows. The NTSC transmission signal equation is Y = 0.30R + 0.59G + 0.11B
RY=0.70R-0.59G-0.11BB-
Y=-0.30R-0.59G+0.89B, and one high-definition transmission signal equation is YHD
= 0.212 R+0.701 G+0.087
B PR = 0.500 R-0.44
5 G-0.055 B=(RY)/1.576
PB=-0.116 R-0.384 G
+0.500 B=(BY)/1.826. The above transformation matrix

[0008]

[0009] Then, the above matrix is

0010

From the relationship 0011

0012

The coefficient can be found as follows. That is, YH
D is the coefficient unit 1 output Y and the coefficient unit 5 output - 0.044 (B
-Y) and the coefficient unit 9 output -0.144 (R-Y), PB is the addition of the coefficient unit 2 output 0.572 (B-Y) and the coefficient unit 7 output 0.079 (R-Y). Addition, PR is coefficient unit 4 output 0.028 (B-Y) and coefficient unit 8 output 0
．． 726 (RY). FIG. 2 shows a basic signal system diagram for both HDTV and NTSC to which the matrix conversion circuit 13 of FIG.
B, PR) as an HDTV signal processing circuit (not shown)
Connect to. In addition, in current broadcasting, the (RY) signal is
/1.14, the (B-Y) signal is multiplied by 1/2.03 and modulated. Therefore, when using a demodulated signal, a signal multiplied by a predetermined coefficient is used as an input to a matrix conversion circuit, or the matrix coefficients are converted.

[0014]

Effects of the Invention As described above, the present invention provides high-definition H
Since the signal processing circuit for DTV is commonly used when inputting NTSC signals, the NTSC signal is used as the HDTV signal Y.
By adding a matrix conversion circuit consisting of an inverter that converts and outputs HD, PB, and PR, a coefficient multiplier with predetermined coefficients, and an adder, it is possible to configure a circuit that reproduces faithful colors and has a cost advantage.

[Brief explanation of the drawing]

FIG. 1 is a matrix circuit that converts an NTSC signal to a Hi-Vision HDTV signal.

FIG. 2 is a basic signal system diagram for HDTV signal processing to which the matrix circuit of FIG. 1 is added.

[Explanation of symbols]

1 Coefficient unit 2 Inverter 3 Coefficient unit 6 Inverter 7 Coefficient unit 10 Adder

Claims (1)

[Claims] Claim 1: In a video signal processing circuit such as a high-definition HDTV, an NTSC luminance signal Y is connected to a first coefficient multiplier, and a color difference signal B-Y is connected to a second coefficient multiplier, a third coefficient multiplier, and a first coefficient multiplier. connected to a fourth coefficient multiplier via an inverter,
The color difference signal R-Y is connected to a seventh coefficient unit via a fifth coefficient unit, a sixth coefficient unit, and a second inverter, and
The output of the coefficient unit, the output of the fourth coefficient unit, and the output of the seventh coefficient unit are connected to the first adder, and the output of the second coefficient unit and the output of the fifth coefficient unit are connected to the first adder.
The output of the coefficient unit is connected to a second adder, the output of the third coefficient unit and the output of the sixth coefficient unit are connected to the third adder, and the high-definition luminance signal is output from the first adder. YHD is output, and the high-definition color difference signal P is output from the second adder.
NTSC color difference signals B-Y, R-, which outputs a high-definition color difference signal PR from the third adder;
A television receiver comprising a matrix circuit for converting Y high-definition color difference signals PB and PR.