JPH07245743A - High definition television signal processing circuit - Google Patents

Abstract

PURPOSE:To reduce power consumption and heat generation by stopping an output of an NTSC conversion circuit when an NTSC conversion signal is not in use. CONSTITUTION:A MUSE decode circuit 4 converts a MUSE signal into a High Vision signal (R, G, B signal), a D/A converter circuit 5 converts the High Vision signal into an analog signal and R, G, B signals are outputted and an NTSC conversion circuit 6 converts the MUSE signal into the NTSC signal. Furthermore, an NTSC conversion output use detection circuit 7 detects whether or not an output of the NTSC conversion signal is in use. For example, the presence of connection of an external connection terminal or the presence of selection of a slave pattern is detected and the result is outputted to a signal stop circuit 8. Then the signal stop circuit 8 stops an input signal to the NTSC conversion circuit 6 based on an output of the NTSC conversion output use detection circuit 7. That is, when an output of the NTSC conversion signal is not in use, the signal stop circuit 8 stops, e.g. the input signal to the NTSC conversion circuit 6 or supply of power based on an output of the NTSC conversion output use detection circuit 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high definition television signal processing circuit.

[0002]

2. Description of the Related Art In recent years, there has been an increasing interest in band compression transmission systems in order to efficiently transmit wideband high-definition television signals within a limited transmission band. For example, as one of the band compression transmission systems, MUSE (Mult) that band-compresses high-definition television (high-definition) signals.
The iple Sub-Nyquist Sampling Encoding method has been proposed by the Japan Broadcasting Corporation (NHK). For details of the contents, refer to “High-definition Television Satellite 1-Channel Transmission System (MUSE)” Yuichi Ninomiya et al. (Technical Report of IEICE, IE 84-7
2.1984).

A conventional high-definition television signal processing circuit will be described below with reference to the drawings. FIG. 2 is a block diagram of a conventional high-definition television signal processing circuit.

In FIG. 2, 1 is an input terminal for a MUSE signal, 2 is an A / D conversion circuit for converting into a digital signal, 3 is a synchronous processing circuit for detecting a synchronous signal, and 4 is MUSE.
A MUSE decoding circuit for converting a signal into a high-definition signal, 5 is a D / A conversion circuit for converting into an analog signal, and 6 is an NTSC conversion circuit for converting into an NTSC signal.

The operation of the high-definition television signal processing circuit configured as described above will be described below with reference to FIG. The MUSE signal input to the MUSE signal input terminal 1 is converted into a 10-bit digital signal by the A / D conversion circuit 2. The synchronization processing circuit 3 detects a synchronization signal (frame pulse or the like) from the digital signal. The MUSE decoding circuit 4 converts the MUSE signal into a high-definition signal (RGB signal). That is, the reverse process of the process performed on the transmitting side is performed. Furthermore, the D / A conversion circuit 5
Is converted into an analog signal and the R, G, B signals are output.
In addition, the NTSC conversion circuit 6 sends the MUSE signal to the NTS
Convert to C signal.

[0006]

However, the above-mentioned conventional method has a problem that power consumption and heat generation are large because a signal is always output regardless of the use of the output of the NTSC conversion circuit.

In the above conventional method, the input signal is M
Even if the signal is not a USE signal, the decoding process of the MUSE signal is performed, and therefore, there is a problem that power consumption and heat generation are large.

The present invention solves the above-mentioned conventional problems and, if the output of the NTSC conversion circuit is not used, it is NT.
The output of the SC conversion circuit is stopped to reduce power consumption and heat generation.

The present invention solves the conventional problems and reduces power consumption and heat generation when the input signal is not the MUSE signal.

[0010]

In order to achieve this object, a high-definition television signal processing circuit according to the present invention is an NTS.
A C conversion output use detection circuit and a signal stop circuit are provided.
When the TSC conversion signal is not used, the output of the NTSC conversion circuit is stopped to reduce power consumption and heat generation.

The high-definition television signal processing circuit of the present invention comprises an internal signal generating circuit, a MUSE signal detecting circuit and a signal switching circuit.

[0012]

According to the first configuration, the use of the NTSC conversion signal is detected by the NTSC conversion output use detection circuit, and when it is not used, the output of the NTSC conversion circuit is stopped by the signal stop circuit to reduce power consumption and heat generation. It is something to reduce.

According to the second configuration, the MUSE signal detection circuit detects the input signal, and when the input signal is not the MUSE signal, the signal switching circuit switches to the output (certain fixed data) of the internal signal generation circuit to reduce power consumption and It reduces heat generation.

[0014]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a high-definition television signal processing circuit showing an embodiment of the present invention.

In FIG. 1, 1 is an input terminal for a MUSE signal, 2 is an A / D conversion circuit for converting into a digital signal, 3 is a synchronous processing circuit for detecting a synchronous signal, and 4 is MUSE.
A MUSE decoding circuit for converting a signal into a high-definition signal, 5 is a D / A conversion circuit for converting into an analog signal, and 6 is an NTSC conversion circuit for converting into an NTSC signal. Further, 7 is an NTSC conversion output use detection circuit that detects the use of the NTSC conversion signal output that is the output of the NTSC conversion circuit 6, and 8 is a signal stop circuit that stops the output of the NTSC conversion signal.

The operation of an embodiment of the high-definition television signal processing circuit configured as described above will be described below with reference to FIG. The MUSE signal input to the MUSE signal input terminal 1 is input to the A / D conversion circuit 2 for 10
Convert to bit digital signal. The synchronization processing circuit 3 detects a synchronization signal (frame pulse or the like) from the digital signal.

The MUSE decoding circuit 4 converts the MUSE signal into a high definition signal (RGB signal). That is, the reverse process of the process performed on the transmitting side is performed. Furthermore, D
The A / A conversion circuit 5 converts the analog signal and outputs the R, G, B signals. The NTSC conversion circuit 6 converts the MUSE signal into an NTSC signal.

The NTSC conversion output use detection circuit 7 detects whether the output of the NTSC conversion signal is used. For example, the presence or absence of the connection of the external connection terminal or the presence or absence of the selection of the child screen is detected and output to the signal stop circuit 8. The signal stop circuit 8 stops the input signal of the NTSC conversion circuit 6 by the output of the NTSC conversion output use detection circuit 7.

As described above, according to this embodiment, the NTSC
A conversion output use detection circuit 7 and a signal stop circuit 8 are provided,
If the output of NTSC conversion signal is not used, NT
With the output of the SC conversion output use detection circuit 7, the signal stop circuit 8 can stop the input signal or power supply of the NTSC conversion circuit 6, for example, to reduce power consumption and heat generation.

(Embodiment 2) Another embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a block diagram of the high definition television signal processing circuit of the present invention.

In FIG. 2, 1 is an input terminal for a MUSE signal, 2 is an A / D conversion circuit for converting into a digital signal, 3 is a synchronous processing circuit for detecting a synchronous signal, and 4 is MUSE.
MUSE decoding circuit for converting signal to high-definition signal, 5 D / A conversion circuit for converting to analog signal, 9 MUSE signal detecting circuit for detecting MUSE signal, 10 internal signal generating circuit for generating a certain fixed value , 11 are signal switching circuits for switching signals.

The operation of the high-definition television signal processing circuit configured as described above will be described below with reference to FIG. In FIG. 2, the NTSC conversion circuit 6, the NTSC conversion output use detection circuit 7, and the signal stop circuit 8 which are not described among the constituent requirements described in the first embodiment are shown.
The description of the above will be omitted in this embodiment, but even if it is used, it has the same effect as the above.

M input to the MUSE signal input terminal 1
The USE signal is converted into a 10-bit digital signal by the A / D conversion circuit 2. The synchronization processing circuit 3 detects a synchronization signal (frame pulse or the like) from the digital signal.

The MUSE signal detection circuit 9 detects whether the input signal is the MUSE signal or not from the digital signal and controls the signal switching circuit 11. The internal signal generation circuit 10 generates a certain fixed value.

Next, in the signal switching circuit 11, the M
The output of the USE signal detection circuit 9 is switched between the output of the A / D conversion circuit 2 and the output of the internal signal generation circuit 10. That is, when the input signal is the MUSE signal, it is switched to the output of the A / D conversion circuit 2, and when it is not the MUSE signal, it is switched to the output of the internal signal generation circuit 10.

The MUSE decoding circuit 4 converts the MUSE signal into a high definition signal (RGB signal). That is, the reverse process of the process performed on the transmitting side is performed. Furthermore, D
The A / A conversion circuit 5 converts the analog signal and outputs the R, G, B signals.

As described above, according to this embodiment, the MUSE
When the signal detection circuit 9, the internal signal generation circuit 10, and the signal switching circuit 11 are provided and the input signal is not the MUSE signal,
The output of the MUSE signal detection circuit 9 allows the signal switching circuit 11 to switch from the output of the A / D conversion circuit 2 to the output of the internal signal generation circuit 10 to reduce power consumption and heat generation.

[0028]

As described above, according to the present invention, the NTSC conversion output use detection circuit and the signal stop circuit are provided, and when the output of the NTSC converted signal is not used, the signal is stopped by the output of the NTSC conversion output use detection circuit. NTSC in the circuit
The input signal of the conversion circuit can be stopped to reduce power consumption and heat generation.

The present invention further comprises a MUSE signal detection circuit, an internal signal generation circuit, and a signal switching circuit. When the input signal is not the MUSE signal, the output of the MUSE signal detection circuit causes the signal switching circuit to switch the A / D conversion circuit. The output can be switched to the output of the internal signal generation circuit to reduce power consumption and heat generation.

[Brief description of drawings]

FIG. 1 is a block diagram of a high-definition television signal processing circuit showing an embodiment of the present invention.

FIG. 2 is a block diagram of a high-definition television signal processing circuit showing another embodiment of the present invention.

FIG. 3 is a block diagram of a conventional high-definition television signal processing circuit.

[Explanation of symbols]

 1 MUSE signal input terminal 2 A / D conversion circuit 3 Synchronization processing circuit 4 MUSE decoding circuit 5 D / A conversion circuit 6 NTSC conversion circuit 7 NTSC conversion output use detection circuit 8 Signal stop circuit 9 MUSE signal detection circuit 10 Internal signal generation Circuit 11 Signal switching circuit

Claims (2)

[Claims] 1. A high-definition television signal processing circuit comprising a MUSE decoding circuit for decoding a band-compressed high-definition television signal and an NTSC conversion circuit for converting the band-compressed high-definition television signal into an NTSC conversion circuit output from the NTSC conversion circuit. The NTS conversion output use detection circuit for detecting the use state of the signal output and the signal stop circuit for stopping the output of the NTSC converted signal are provided, and the NTS
A high-definition television signal processing circuit, which stops the output of the NTSC conversion circuit when the C conversion signal is not used. 2. A high-definition television signal processing circuit comprising a MUSE decoding circuit for decoding a band-compressed high-definition television signal, and a MUSE signal detecting circuit for detecting the MUSE signal and generating a certain fixed data. An internal signal generating circuit and a signal switching circuit for switching the signal are provided, and when the input signal is not the MUSE signal, the signal switching circuit is switched to the output of the internal signal generating circuit by the output of the MUSE signal detection circuit. High-definition television signal processing circuit.