JPH0358691A - Television signal converter - Google Patents

Abstract

PURPOSE:To attain color reproduction of a high definition television signal with fidelity hy providing a matrix conversion circuit converting a matrix of the high definition television signal into a matrix of a current standard television signal. CONSTITUTION:A matrix conversion circuit 9 is inserted between an output of a signal processing circuit 3 and D/A converters 5-7. Then a luminance signal and color difference signals of a high definition television signal outputted from the signal processing circuit 3 are converted into a Y signal, (R-Y) signal and a (R-Y) signal in matching with the luminance system of the current standard television signal by the matrix conversion circuit 9 and they are inputted to the D/A converters 5-7. Thus, color reproduction with fidelity with the high definition television signal is applied regardless of simple constitution.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention provides a function to eliminate differences in hue due to differences in matrix when converting a high-definition television signal to a current standard television signal with a different aspect ratio or matrix. The present invention relates to a television signal conversion device having the following.

BACKGROUND OF THE INVENTION In recent years, television signals such as high-definition television that have a different transmission method from conventional television signals have been developed and come into use. Accordingly, it has become necessary to convert high definition television signals to current standard television signals and to reproduce them on conventional television receivers.

FIG. 2 shows a schematic diagram of a conventional television signal converter. In the figure, 1 is an A/D converter that converts the analog video detection signal from the tuner's detection circuit (not shown) into a digital signal, 2 is the RAM that stores the video signal, 3 is the number of scanning lines, A signal processing circuit that converts the aspect ratio; 4 is a synchronization processing circuit that detects the synchronization of the video detection signal and generates a synchronization signal of a standard television signal; and 5 to 7 are digital signals processed by the signal processing circuit 3. It is a D/A converter that converts the Y signal, R-Y signal, and B-Y signal into analog signals.
is an encoder that converts the outputs of the D/A converters 5 to 7 into current standard television signals. Note that A is an input terminal for a high-definition television signal, and B is an output terminal for a standard television signal.

The operation of the television signal converter configured as described above will be explained below.

The high-definition television signal from the tuner/detection circuit is transmitted to the A. / Converted to digital signal by D converter 1,
The signal processing circuit 3 converts the aspect ratio and the number of scanning lines. At this time, the RAM 2 stores video signals to be displayed on the screen. Furthermore, the synchronization processing circuit 3 detects synchronization of high-definition television signals and generates synchronization of standard television signals. The Y signal, RY signal, and BY signal, which are digital signals output from the signal processing circuit 3, are converted into analog signals by D/A converters 5 to 7, respectively, and the outputs of the D/A converters 5 to 7 are converted to analog signals. The encoder 8 converts the signal into a current standard television signal and displays it on a television receiver.

Problems to be Solved by the Invention However, as can be seen from the operation of the conventional example, when converting a high-definition television signal with a different brightness signal system (matrix) from the current standard television signal into the current standard television signal, the matrix 5. This causes errors in color reproduction, resulting in different hues on the screen.

SUMMARY OF THE INVENTION Based on these problems, the present invention provides a television signal conversion device that eliminates the drawbacks and faithfully reproduces the color of high-definition television signals with a simple design. .

Means for Solving the Problems The television signal conversion device of the present invention converts an A/D converter, a signal processing circuit, a synchronization processing circuit, and a matrix for a high-definition television signal into a current standard television signal. It is characterized by being equipped with a matrix conversion circuit that converts it into a matrix, a memory (RAM) that stores video signals, and a D/A converter.

According to the television signal converting device of the present invention, color reproduction of high-definition television signals can be achieved by including a matrix conversion circuit that converts the 71x of high-definition television signals into a matrix of current standard television signals. can be carried out faithfully.

Example Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

In this figure, parts common to those in FIG. 2 are given the same reference numerals, and detailed explanations will be omitted. In the wooden structure, a matrix conversion circuit 9 is inserted between the output of the signal processing circuit 3 and the D/A converters 5 to 7.

As can be seen from FIG. 1, the Y signal, R-Y signal, and B-Y signal output from the signal processing circuit 3 are processed by the matrix conversion circuit 9 to produce the Y' signal ( RY)' signal, (B/Y)' signal,
The signal is converted into a D/A converter 5 to 7 and inputted to the D/A converters 5 to 7.

By inserting the matrix conversion circuit 9 in this way, it is possible to faithfully reproduce the color of the current standard television receiver to a high-quality television signal.

Effects of the Invention As described above, the present invention provides a television signal that can reproduce colors faithful to high-definition television signals despite having a simple configuration that only requires the insertion of a matrix conversion circuit. This invention can provide a converting device, and can be said to be an invention with outstanding practical effects.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram of a television signal converter according to an embodiment of the present invention, and FIG. 2 is a schematic block diagram of a conventional television signal converter. ■...A/D converter, 2...RA
M, 3...Signal processing circuit, 4...Synchronization processing circuit, 5-6...D/A converter, 8.
... Encoder, 9 ... Matrix conversion circuit.

Claims (1)

[Claims] It includes a signal processing circuit that receives a high-definition television signal and converts it into a current standard television signal with a different aspect ratio, and a matrix conversion circuit that converts the matrix of the high-definition television signal into a matrix of the current standard television signal. television signal converter.