JPH04196786A - Television receiver - Google Patents

Abstract

PURPOSE:To allow the user to enjoy two different broadcast system programs simultaneously by using a picture memory required to receive the two different broadcast systems in common so as to reduce the cost. CONSTITUTION:An output signal of a mixer circuit 205 an output signal of a moving picture use YC separator circuit 203 are inputted to a selector 250, either signal is selected alternatively according to a selection signal and a selected output is fed to a decoding circuit 209 and a subtractor 214. When the selection signal selects the NTSC system, the selector 250 selects a signal from a mixer circuit 205. In this case, a high picture quality video signal without cross color and cross luminance is reproduced by movement adaptive processing. Moreover, in this case, a MUSE(Multiple Sub-Nyquist Sampling Encoding) signal converted into a digital data is inputted to a MUSE signal processing circuit 200. Thus, the capacity of a picture memory is saved, the cost is reduced and the user enjoys both the programs simultaneously.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to television signals based on the MUSE system and NT
The present invention relates to a television signal receiver that can receive television signals of different transmission systems, such as the SC system.

Conventional technology MUSE is an effective technology for compressing and transmitting wideband high-definition video signals into a practical level band that can be transmitted.
(Multiple 5ub-Nyquist sam
plingEncoding) method has been proposed (Ninomiya, et al., “Satellite one-channel transmission system for high-definition television (MUSE)” J.Television Society Technical Report TEBS95
-2 pages 37-42).

As described in the paper, this method compresses the band to about 1/4 and transmits it by performing 4:1 sub-Nyquist sampling on a wideband high-definition television signal in four fields. This compressed high-quality video signal (hereinafter referred to as MUSE signal) uses intra-field, inter-field, and inter-frame interpolation on the receiving side to approximately reproduce the sample point information that was not transmitted. The MUSE signal processing circuit then restores the original broadband, high-quality television signal.

FIG. 7 shows a simple configuration of the MUSE signal receiver.

In FIG. 7, 100 is a MUSE signal processing circuit, 101
is an AD converter, 102 is a still image processing circuit, 103 is a moving image processing circuit, 104 is a motion detection circuit, 105 is a mixing circuit,
107 and 108 are image memories, 109 is a decoding circuit,
110, 111° and 112 are DA converters, and 113 is a high-definition television monitor.

The input baseband MUSE signal is sent to AD converter 1
01, it is converted into a digital signal at a sampling rate of 16.2 MHz, and the still image processing circuit l○2. Video processing circuit 103. Motion detection circuit 104. The control signal generation circuit 1061 is supplied to the image memory 107, respectively.

Here, the image memory 107 is a memory that delays the input signal by one frame period. The still image processing circuit 102 includes an interframe interpolation circuit 1021 and an interfield interpolation circuit 1022.
and an image memory 1023. First, interpolation processing is performed in an interframe interpolation circuit 1021 using the input current signal and a one-frame period delayed signal from the image memory 107, and then Interpolation signal and image memory 10
An interfield interpolation circuit 1022 performs interpolation processing using the interpolation signal delayed by one field period from 23 to obtain untransmitted sample points.The interpolation signal is connected to one input of the mixer 105. Ru. Similarly, the moving image processing circuit 103 includes an intra-field interpolation circuit 1031, which performs interpolation processing using only the current signal to obtain sample points that have not been transmitted. The interpolated signal is connected to the other input of mixer 105. The motion detection circuit 104 is supplied with signals from the AD converter 101 and signals from the image memories 107 and 108. Here, the capacity of the image memory 108 is the same as that of the image memory 107, and a delay of one frame period is realized. Therefore, the motion detection circuit 104 is supplied with the current signal, one frame period delayed signal, and two frame period delayed signal, and based on these signals, the amount of motion between one frame or between two frames is determined. Detect. The detected amount of motion is connected to a mixing circuit 105. The mixing circuit 105 controls and outputs the mixing ratio of the signal from the still image processing circuit 102 and the signal from the moving image processing circuit 103 based on the amount of motion from the motion detection circuit 106. The signal interpolated by such motion adaptive processing is decoded into RGB digital data in the decoding circuit 109. These digital data are D
The signal is converted into analog data by A converters 110, 111, and 112, and displayed on a high-definition television monitor 113 as the original broadband high-definition video signal.

On the other hand, it is known that even in the current NTSC system, it is possible to reproduce high-quality images without cross color or cross luminance by separating the luminance signal Y and color signal C (hereinafter referred to as YC separation) using an image memory. .

FIG. 8 shows the configuration of a high-quality NTSC signal receiver. In FIG. 8, 200 is an NTSC signal processing circuit, 201 is an AD converter, 202 is a still image YC separation circuit, 203 is a moving image YC separation circuit, 204 is a motion detection circuit, 205 is a mixing circuit, 207 and 208 are image 209 is a memory, a decoding circuit, 210, 211, 212 are DA converters, 213 is a standard television monitor, and 214 is a subtracter.

The input baseband NTSC signal is sent to the AD converter 20
1, it is converted into a digital signal and sent to a still image YC separation circuit 2.
02. Video YC separation circuit 203゜Motion detection circuit 204
2 image memory 207. Each is supplied to one input terminal of the subtracter 214.

Here, the image memory 207 is a memory that delays the input signal by one frame period. Therefore, the still image YC separation circuit 202 performs YC separation by performing interframe calculations using the input current signal and the one frame period delayed signal from the image memory 207, and the separated color signals are transferred to one side of the mixing circuit 205. Connect to the input of Similarly, the video YC separation circuit 203 performs YC separation using only the current signal and performs calculations using signals in the same field, and connects the separated color signals to the other input of the mixing circuit 205. The motion detection circuit 204 is supplied with signals from the AD converter 201 and signals from the image memories 207 and 208. Here, the capacity of the image memory 208 is the image memory 2
This is the same as 07 and realizes a delay of one frame period. Therefore, the motion detection circuit 204 receives the current signal and the delayed signal by one frame period.

Two-frame period delayed signals are supplied, and based on these signals, the amount of motion between one frame and between two frames of an image is detected. The detected amount of movement is sent to the mixing circuit 205.
connected to. In the mixing circuit 205, the motion detection circuit 204
The mixing ratio of the separated color signal from the still image YC separation circuit 202 and the separated color signal from the moving image YC separation circuit 203 is controlled and output according to the amount of movement from the YC separation circuit 202 for still images. The color signal obtained by the motion adaptive processing in this way is sent to the decoding circuit 2.
09 and the other input of the subtracter 214. A subtracter 214 obtains a luminance signal by subtracting the color signal from the baseband NTSC signal.

The luminance signal is connected to a decoding circuit 209. The separated color signal and luminance signal are decoded into RGB digital data in a decoding circuit 209. These digital data are converted into analog data by DA converters 210, 211, and 212, and output to a standard television monitor 213 as a high-quality video signal without cross color or cross luminance.

Problems to be Solved by the Invention In the near future, when high-definition broadcasting using the MUSE system will begin,
A television receiver is required that can receive both MUSE and NTSC television signals. However, mounting the signal processing circuits shown in FIGS. 7 and 8 independently has the disadvantage that it leads to a large increase in cost.

Therefore, in view of the above problems, the present invention has developed the MUSE system and the NTS system.
The present invention provides a television receiver that can receive television signals of different broadcasting systems such as the C system and that can reduce costs.

Means for Solving the Problems In order to solve the above problems, the television receiver of the present invention includes a selector circuit that inputs a high-definition television signal and a current standard television signal and selectively outputs it in accordance with a selection signal; a first image memory that receives the selected output signal as an input; a second image memory that receives the output signal of the first image memory as an input; a control signal generation circuit for controlling the first and second image memories as appropriate for each of the signals; and an output of the high definition television signal and the first image memory which are input signals to the selector circuit. a first signal processing circuit to which the signal and the output signal of the second image memory are supplied, the current standard television signal which is the input signal to the selector circuit, the output signal of the first image memory and the first signal processing circuit; and a second signal processing circuit to which the output signal of the second image memory is supplied.

action The present invention has two different features depending on the configuration described above.

By sharing the image memory necessary for receiving images of the broadcasting systems, it is possible to significantly reduce costs and to enjoy programs of these two different broadcasting systems at the same time.

Embodiment Hereinafter, a format conversion circuit according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing the configuration of a television receiver in a first embodiment of the present invention. In Figure 1, 1 is the baseband MUSE signal input terminal, 2 is the baseband NT
SC signal input terminals, 101 and 201 are AD converters, 31 and 36 are selectors, 32 and 33 are image memories, 34 is a control signal generation circuit for MUSE, 35 is an N
Control signal generation circuit for TSC, 37 is MUSE/NTSC
Memory selection terminal (hereinafter referred to as M/N memory selection terminal),
100 is a MUSE signal processing circuit, 200 is an NTSC signal processing circuit, 110, 111, 112°210.211.
212 is a DA converter, and 113 and 213 are monitors. First, the baseband MUS applied to input terminal 1
The E signal is supplied to an A, D converter 101. The output of the AD converter 101 is connected to one input terminal of the selector 31 and M
The signal is supplied to the USE signal processing circuit 100. Similarly, the baseband NTSC signal applied to input terminal 2 is supplied to AD converter 201. The output of the AD converter 201 is supplied to the other input terminal of the selector 31 and the NTSC signal processing circuit 200. The output of selector 31 is supplied to image memory 32.

The output of the image memory 32 is sent to the image memory 33. It is supplied to the MUSE signal processing circuit 100 and the NTSC signal processing circuit 200. The output of the image memory 33 is supplied to the MUSE signal processing circuit 100 and the NTSC signal processing circuit 200. Further, the outputs of the MUSE control signal generation circuit 34 and the NTSC control signal generation circuit are connected to two terminals of the selector 36, respectively. The output of selector 36 is connected to the control inputs of image memories 32 and 33. The M/N memory selection signal applied to the M/N memory selection terminal is sent to the selector 31. Selector 36. Connected to the MUSE signal processing circuit and the NTSC signal processing circuit.

The operation of the television receiver configured as described above will be explained using FIG. 1. In FIG. 1, for example, when MUSE is selected by the selection signal input to the M/N mesori selection terminal 37, the selector 31
1 is selected and the MUSE signal converted into digital data is supplied to the memory 32. Further, the selector 36 selects the control signal from the MUSE control signal generation circuit and uses it to control the image memories 32 and 33.

In this case, the control signal is a signal that controls the image memories 32 and 33 to each achieve a one frame period delay at the MUSE signal rate. MUSE signal is 16.2
Since sampling is performed at MHz, the number of samples in one horizontal scanning period is 480 samples, and in one frame period there are 5 samples.
40,000 (480×1125) samples, and memories 32 and 33 are each set to a delay of 540,000 samples. Therefore, the output of the image memory 32 is the MUSE signal delayed by one frame period, and the output of the image flaw memory 33 is the MUSE signal delayed by two frame periods.

These signals are supplied to the MUSE signal processing circuit 100. The MUSE signal processing circuit 100 is composed of, for example, the circuit shown in FIG. Basically, it is the same as the conventional example shown in FIG. It selectively selects one of the signals according to the
Supply on 09. When the selection signal selects MUSE, selector 150 selects the signal from mixing circuit 105. In this case, the operation is the same as that described in FIG. 7 of the conventional example, and a high-quality video signal subjected to motion adaptive processing is reproduced.

Also, at this time, the NTSC current signal converted into digital data is input to the NTSC signal processing circuit 200. The NTSC signal processing circuit 200 is composed of, for example, the circuit shown in FIG. Basically, it is the same as the conventional example shown in FIG. 8, but a selector 250 is newly provided, and the output signal of the mixing circuit 205 and the output signal of the video YC separation circuit 203 are input to the selector 250. Either signal is alternatively selected according to the M/N memory selection signal, and the selected output is supplied to one input terminal of decoding circuit 209 and subtracter 214. When the selection signal selects MUSE, the selector 250 selects the signal from the moving image YC separation circuit 203. In other words, the YC-separated video is reproduced using only the current signal.Next, when NTSC is selected by the selection signal input to the M/N memory selection terminal 37, the selector 31
1 is selected, and the memory 32 is supplied with an NTSC signal converted into digital data. Further, the selector 36 selects a signal from the NTSC control signal generation circuit and uses it to control the image memories 32 and 33. In this case, the sub-part signal is a signal that controls the image memories 32 and 33 to each achieve a one frame period delay at the NTSC signal rate. NTSC signal for example 14
．． When sampling at 3 MHz (4x color subcarrier frequency), the number of samples in one horizontal scanning period is 910 samples, and in one frame period there are 477,750 (910 x 52
5) samples, with memories 32 and 33 each set to a delay of 477,750 samples. Therefore, the output of the image memory 32 is delayed by one frame period.
The output of the signal and image memory 33 has a two-frame period delay N.
A TSC signal is obtained. These signals are supplied to the NTSC signal processing circuit 200.

The NTSC signal processing circuit 200 is composed of, for example, the circuit shown in FIG. It is basically the same as the conventional example shown in FIG. 8, but a selector 250 is newly provided, and the mixing circuit 2
05 and the output signal of the video YC separation circuit 203 are input to the selector 250, one of the signals is alternatively selected according to the selection signal, and the selected output is sent to the decoding circuit 20.
9 and subtractor 214. Selection signal is NTSC
is selected, the selector 250 is the mixing circuit 205
Select the signal from. In this case, the operation is the same as that described in FIG. 8 of the conventional example, and motion adaptive processing is performed to reproduce a high-quality video signal without cross color or cross luminance. At this time, the MUSE current signal converted into digital data is input to the MUSE signal processing circuit 200. As mentioned above, the MUSE signal processing circuit is set to selectively output the video processing circuit when the selection signal selects NTSC, and the interpolated high-quality bite is reproduced using only the MUSE current signal. Ru.

Here, the number of samples in one frame period at the 16.2M ratio rate of the MUSE signal is 540,000 samples, which is NTS
In the case of a C signal, there are 477,750 samples at a 14.3 MHz rate, so it is possible to share the image memory in terms of capacity. Also, the operating speed is 16.2M and 14.3M.
Since it is Hz, there is no problem in terms of sharing.

It goes without saying that the image memory control signal is generally a signal indicating the address of the image memory. In the case of an image memory having an internal address generator, this signal is used to control the built-in address generator.

As described above, according to this embodiment, by sharing a large-capacity image memory, it is possible to reduce the image memory capacity required for processing, resulting in a significant cost reduction.

Furthermore, since the unselected MUSE signal and NTSC signal operate on moving image processing that does not require an image memory, both signals can be enjoyed at the same time.

FIG. 4 is a diagram showing the configuration of a television receiver in a second embodiment of the present invention. In Fig. 4, 1 is the baseband MUSE signal input terminal, 2 is the baseband NT
SC signal input terminal, 101 and 201 are AD converters, 31 and 36 are selectors, 32 and 33 are image memories, 34 is a control signal generation circuit for MUSE, 35 is an NT
The SC control signal generation circuit, 37 is an M/N memory selection terminal, 100 is a MUSE signal processing circuit, and 200 is an NTSC signal processing circuit, which is the same as the configuration shown in FIG. 1. The difference from the configuration shown in Figure 1 is the NTSC signal processing circuit 2.
The output of 00 is supplied to the scanning line number conversion circuit 301, and the MUS
Output signal of E signal processing circuit 100 and scanning line number conversion circuit 3
The output signals of 01 are respectively supplied to the combining circuit 302, and the output of the combining circuit 302 is sent to the DA converters 310, 311, 31.
2 and their output signals are connected to high-definition television monitors 113, respectively.

The operation of the television receiver configured as described above will be explained using FIG. 4. In FIG. 4, for example, when MUSE is selected by the selection signal input to the M/N memory selection terminal 37, the output of the MUSE signal processing circuit 100 is interpolated by motion adaptive processing as explained in the first embodiment. A high-quality video signal can be obtained. Also NTS
The output of the C signal processing circuit 200 is a standard video signal that has been subjected to YC separation using a moving image YC separation filter. The standard video signal undergoes scanning line number conversion in a scanning line number conversion circuit 301. In other words, the number of scanning lines of a standard television signal is 52.
The number of scanning lines is converted from 5 to 1,125 scanning lines of a high-definition television signal. This means that it can be displayed on a high-definition television monitor. The synthesis circuit 302 is supplied with a high-quality video signal, a standard video signal with the number of scanning lines converted, and a selection signal.

In the synthesis circuit 302, according to the selection signal, the high-quality video signal is displayed as the main screen as shown in FIG. 5, and the standard video signal whose number of scanning lines has been converted is inserted and synthesized on the main screen as the sub-screen. Composition can be easily performed by reducing the size of the sub-screen video using a memory or the like and displaying it in accordance with the timing of the main screen. The combined signal is sent to a DA converter 310,
The signals are converted into analog signals at steps 311 and 312 and displayed on the high-definition television monitor 113.

Next, when NTSC is selected by the selection signal input to the M/N memory selection terminal 37, the output of the MUSE signal processing circuit 100 is a high-quality signal interpolated only by video processing, as explained in the first embodiment. A video signal can be obtained. Further, as the output of the NTSC signal processing circuit 200, a high quality standard video signal which is YC separated and free of cross color and cross luminance is obtained through motion adaptive processing. The following operations are as described above, and as shown in FIG. 6, a composite screen is obtained in which the high-definition standard video signal converted to the number of scanning lines is the main screen and the high-definition video signal is the sub-screen, and the high-definition television monitor 113 will be displayed.

Although RGB signals are used as input signals to the scanning line number conversion circuit in the embodiments described above, the present invention is not limited to this, and similar processing can be performed using luminance signals and color difference signals. Furthermore, the display method is not limited to the one described above, and may be arbitrary, such as displaying only the main screen or the sub-screen, or exchanging the main screen and the sub-screen.

As described above, according to this embodiment, by sharing a large capacity image memory, it is possible to reduce the image memory capacity required for processing, and it is also possible to enjoy programs of two different broadcasting systems on one monitor. can.

Effects of the Invention As described above, the present invention provides a selector circuit that inputs a high-definition television signal and a current standard television signal and selectively outputs it according to a selection signal, and a first image that receives the selection output signal as input. a second image memory receiving the output signal of the first image memory; and a second image memory receiving the output signal of the first image memory; a control signal generation circuit for controlling the second image memory, the high-definition television signal that is an input signal to the selector circuit, and the first image memory;
a first signal processing circuit to which the output signal of the image memory and the output signal of the second image memory are supplied; By providing a second signal processing circuit to which the output signal and the output signal of the second image memory are supplied, it is possible to obtain the necessary signals for receiving different broadcasting systems such as a high-definition television signal and a current standard television signal. By sharing the image memory, it is possible to reduce the image memory, resulting in a significant cost reduction, and it is possible to enjoy both programs at the same time.

[Brief explanation of the drawing]

, FIG. 1 is a block diagram of a television receiver according to the first embodiment of the present invention, FIG. 2 is a block diagram of a MUSE signal processing circuit, and FIG. 3 is a block diagram of a N T & C signal processing circuit.
FIG. 4 is a block diagram of the television receiver in the second embodiment, FIGS. 5 and 6 are screen diagrams for explaining the operation of the television receiver in the second embodiment, and FIG. FIG. 8 is a block diagram of a conventional MUSE signal receiver. FIG. 8 is a block diagram of a conventional high-quality NTSC signal receiver. 31...Selector, 32...Image memory, 33...Image memory, 100...
MUSE signal processing circuit, 101...AD converter, 200...NTSC signal processing circuit, 201...
...AD converter. Name of agent Patent attorney Akira Koeji Akira and 2 other persons

Claims (4)

[Claims] (1) A television receiver that can simultaneously process a high-definition television signal band-compressed using the sub-Nyquist sampling method that goes through one cycle in four fields and a current standard television signal, into which the high-definition television signal and the current standard television signal are input. a selector circuit that selectively outputs the output signal according to a selection signal, a first image memory that receives the selection output signal as an input, and a second image memory that receives the output signal of the first image memory as an input. , a control signal generation circuit for controlling the first and second image memories to suit each of the high-definition television signal and the current standard television signal according to the selection signal; and an input signal to the selector circuit. a first signal processing circuit to which the high-definition television signal, the output signal of the first image memory, and the output signal of the second image memory are supplied; A television receiver comprising a second signal processing circuit to which a standard television signal, an output signal of the first image memory, and an output signal of the second image memory are supplied. (2) A television receiver that can simultaneously process a high-definition television signal whose band has been compressed using the sub-Nyquist sampling method that goes through four fields and a current standard television signal, and which inputs the high-definition television signal and the current standard television signal. a selector circuit that selectively outputs the output signal according to a selection signal, a first image memory that receives the selection output signal as an input, and a second image memory that receives the output signal of the first image memory as an input. , a control signal generation circuit for controlling the first and second image memories to suit each of the high-definition television signal and the current standard television signal according to the selection signal; and an input signal to the selector circuit. a first signal processing circuit to which the high-definition television signal, the output signal of the first image memory, and the output signal of the second image memory are supplied; a second signal processing circuit to which the standard television signal, the output signal of the first image memory and the output signal of the second image memory are supplied, and a scanning circuit to which the output signal of the second signal processing circuit is supplied; A television receiver comprising: a line number conversion circuit; and a synthesis circuit that selects or synthesizes and outputs the output signal of the first signal processing circuit and the output signal of the scanning line number conversion circuit. (3) The first signal processing circuit includes a video processing circuit, a still image processing circuit, a mixing circuit that mixes and outputs an output signal of the video processing circuit and an output signal of the still image processing circuit, and an output of the mixing circuit. 3. The television receiver according to claim 1, further comprising a circuit for setting a signal only to an output signal of said moving image signal processing in accordance with said selection signal. (4) The second signal processing circuit includes a video processing circuit, a still image processing circuit, a mixing circuit that mixes and outputs the output signal of the video processing circuit and the output signal of the still image processing circuit, and an output of the mixing circuit. 3. The television receiver according to claim 1, further comprising a circuit for setting a signal only to an output signal of said moving image signal processing in accordance with said selection signal.