JP2720639B2 - High Definition Television Receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a high-definition television receiver for demodulating a band-compressed high-definition television signal into an original broadband high-definition television signal and reproducing the reproduced signal. A high-definition television receiver for supplying a signal output from the means and a signal delayed by one field period extracted from the cyclic processing path in the frame interpolating means for the field interpolating means for a color difference signal. About.

[0002]

2. Description of the Related Art As a method of band-compressing a wide-band high-definition television signal to a level practical for transmission, a MUSE (Multiple Sub-Ny) for applying a sub-Nyquist sample to the original high-definition television signal in four fields.
quist Sampling Encoding) method ("New transmission method for high-definition television-MUSE"
~ ", July 1984, NHK Giken Monthly Report, Vol. 27, No. 7).

FIG. 5 is a circuit diagram showing a conventional MUSE signal decoder for demodulating a band-compressed high-definition television signal (hereinafter, referred to as a MUSE signal) into an original wideband high-definition television signal. .

[0004] An MUSE signal 2 is supplied to an input terminal 1 and is input to an inter-frame interpolation unit 3.

[0005] In the frame interpolating unit 3, the MUSE signal 2
The signal one field before and the signal three fields before are interpolated in the field memory 6 to generate a signal 7.
A signal 9 is generated by interpolating a signal two fields before the MUSE signal 2 and a signal four fields before the MUSE signal 2 in the field memory 8. Then, in the input switching circuit 4, the signal four fields before included in the signal 9 is replaced with a new MUSE signal.
In place of the signal 2, the cyclic processing is performed so as to obtain the signal 5 in which the current signal and the signal two fields before are interpolated between frames.

A signal 5 is a two-line delay line (2H delay line) 1
1 is a signal 12 delayed by two line periods. Signal 12
Is 1 due to field interpolation of the luminance signal processing unit 10.
It is supplied to a pre-filter 13 consisting of a 2 MHz low-pass filter. The prefilter 13 extracts a frequency component from 0 to 12 MHz and supplies it as a signal 14 to the frequency converter 15. The frequency converter 15 is 32 MHz
The rate signal 14 is converted into a 48 MHz rate signal 16 and supplied to the inter-field interpolation unit 17. The inter-field interpolation section 17 performs an interpolating process on a signal between fields to obtain an inter-field interpolation signal 18. The inter-field interpolation signal 18 is a signal obtained by combining data of four fields of the input MUSE signal, and is input to the mixing circuit 36 of the luminance signal processing unit 10.

The signal 12 is supplied to the field interpolation unit 1
9 as well. The field interpolation unit 19 obtains a signal 20 by field interpolation processing only from the data of the current field. This signal 20 is input to the frequency converter 21 and the time expansion unit 24. The signal 20 input to the frequency converter 21 is converted into a signal of a 48 MHz rate, that is, converted into an intra-field interpolation signal 22 and input to the mixing circuit 36 of the luminance signal processing unit 10. Also, the time extension unit 2
In step 4, the signal 20 at the 32 MHz rate is expanded to a color difference signal at the 8 MHz rate, and is input to the mixing circuit 37 of the color difference signal processing section 23 as an intra-field interpolation signal 25.

Further, the signal 5 is delayed for four lines by a four-line delay line (4H delay line) 26 for inter-field interpolation of the color difference signal processing unit 23, and is also supplied as a signal 27 to a time expansion unit 28. Is done. 32M in the time extension unit 28
The signal 27 at the Hz rate becomes the color difference signal 29 at the 8 MHz rate
And supplied to the inter-field interpolation unit 34. The inter-field interpolation section 34 interpolates the signal between fields to obtain an inter-field interpolation signal 35. The inter-field interpolation signal 35 is a signal obtained by combining data of four fields of the input MUSE signal, and is input to the mixing circuit 37 of the color difference signal processing unit 23.

The mixing circuit 36 of the luminance signal processing unit 10 changes the mixing ratio of the inter-field interpolation signal 18 and the intra-field interpolation signal 22 according to the motion detection signal 45 to obtain a luminance output signal 38, Output to terminal 39.

The mixing circuit 37 of the color difference signal processing section 23 changes the mixing ratio of the inter-field interpolation signal 35 and the intra-field interpolation signal 25 in accordance with the motion detection signal 43 to obtain a color difference output signal 40, Output to terminal 41.

The motion detection signal 43 is generated by a motion detection unit 42 to which the signal 5 is supplied, and the motion detection signal 45 is generated by a frequency converter 44 that converts the motion detection signal 43 to a 48 MHz rate.

FIG. 6 is a circuit diagram showing a configuration of the inter-field interpolation section 34 of the color difference signal processing section 23. Input terminal 46
Is delayed by one field period in the field memory 51 and output as a signal 52. The signal 52 and the signal 29 are alternately selected and output by the selector 48 and output to the output terminal 50 as the inter-field interpolation signal 35. As shown in FIG. 3, the selector 48 converts the data at the position of the mark x (non-sample point) in the line of the current field represented by the solid line with the upper and lower data (marked by the circle) one field period before represented by the broken line. Select to interpolate with the created data. The switching signal is supplied to terminal 49
Given by

[0013]

In this conventional MUSE signal decoder, two to four field memories are required because a signal one to four fields before is required in the cyclic processing of the frame interpolation means. Since the signal before the field period is required for each of the field interpolation units for the luminance signal and the color difference signal, one field memory is required for each, so that the frame interpolation unit and the field interpolation unit A total of four field memories are required. For this reason, there is a disadvantage that it is difficult to reduce the circuit configuration and cost of the high-definition television receiver.

An object of the present invention is to provide a high-definition television capable of reducing the number of field memories required as a decoder of a MUSE signal, reducing the circuit configuration and reducing costs by eliminating the above-mentioned disadvantages. An object of the present invention is to provide a receiver.

[0015]

According to the present invention, there is provided an inter-frame interpolation means for interpolating an input high-definition television signal by cyclic processing using a field memory, and an output from the inter-frame interpolation means. The color difference signal of the high-definition television signal to be interpolated, inter-field interpolation processing means for performing inter-field interpolation and field interpolation means for performing field interpolation, and the inter-field interpolation processing means and the field Mixing means for adaptively mixing the output signal of the interpolation processing means on the basis of the motion detection signal of the high-definition television signal in the high-definition television receiver. And a signal supply unit for extracting the signal from the frame interpolation unit and supplying the extracted signal to the field interpolation unit.

[0016]

The signal supply means fetches a high-definition television signal one field before, which is necessary as the field interpolation means, from the signal path in the frame interpolation means and supplies it to the color difference signal field interpolation means. .

Therefore, it is not necessary to provide a field memory in the interpolating means, and it is possible to reduce the circuit scale and cost.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a main part of a first embodiment of the present invention, and shows a decoder of a MUSE signal.

The first embodiment includes an input switching circuit 4, a field memory 6, and a field memory 8, and receives a MUSE signal 2 from an input terminal 1 and performs frame interpolation by cyclic processing. , A two-line delay line (2H delay line) 11, a pre-filter 13, a frequency converter 15, a field interpolator 17, a field interpolator 19, a frequency converter 21,
A luminance signal processing unit 10 including a mixing circuit 36 for performing field interpolation and field interpolation on the luminance signal of the output signal 5 of the frame interpolation unit 3 in accordance with the motion detection signal 45; The interpolation unit 19, the time extension unit 24, the 4-line delay line (4H delay line) 26, the time extension unit 28, the 4-line delay line 30, the time extension unit 32, the inter-field interpolation unit 34a, and the mixing circuit 37 A color difference signal processing unit 23 that performs field interpolation and field interpolation on the color difference signal of the output signal 5 of the frame interpolation unit 3 in accordance with the motion detection signal 43; And a frequency converter 44 that converts the frequency of the motion detection signal 43 and outputs a motion detection signal 45.

FIG. 2 is a circuit diagram showing details of the inter-field interpolation section 34a of FIG. Field interpolator 34a
Includes only the selector 48 and does not include the field memory.

A feature of the present invention is that, in FIG. 1, a 4-line delay line as signal supply means for taking out a MUSE signal one field period before from the inter-frame interpolating unit 3 and supplying it to the inter-field interpolating unit 34a. 30 and a time decompression unit 32, and the inter-field interpolation unit 34a does not have a field memory as shown in FIG.

That is, the first embodiment differs from the conventional example shown in FIGS. 5 and 6 in the point described in the above-mentioned feature of the present invention.

Therefore, the operation of the first embodiment will be described focusing on parts different from the conventional one. In FIG. 1, the signal 7 output from the field memory 6 of the interpolating unit 3 is
The signal 31 is input to the four-line delay line 30 and delayed by four line periods, and is input to the time expansion unit 32. The time expansion unit 32 time-expands the 32 MHz signal 31 to an 8 MHz signal 33 and inputs the signal to the inter-field interpolation unit 34 a of the color difference signal processing unit 23.

In the inter-field interpolation section 34a, as shown in FIG.
And the output signal 33 of the time extending unit 32 input from the input terminal 47 are alternately selected and output by the selector 48, and output from the output terminal 50 as the inter-field interpolation signal 35. The selector 48 shown in FIG.
As shown in the figure, the position of the mark x (non-sample point) in the line of the current field shown by the solid line is
Select to interpolate the data created by the upper and lower data (marked by ○) before the field period. The switching signal is provided from a terminal 49. FIG. 4 is a block diagram showing a main part of a second embodiment of the present invention, and shows a decoder. In the first embodiment of FIG. 1, the signal 7 is delayed by four lines by the four-line delay line as in the prior art. However, the second embodiment of FIG. As a supply unit, the capacity of the field memory 6a of the frame interpolation unit 3 is adjusted so as to be increased by four lines, and the signal 7a is delayed by four line periods from the conventional output signal 7 to obtain a signal 7a via the time expansion unit 32. This is input to the inter-field interpolation unit 34. In the second embodiment, compared to the first embodiment in FIG.
There is an advantage that one line delay line (the four line delay line 30 in the first embodiment of FIG. 1) can be eliminated. In the second embodiment, the capacity of the field memory 6a is increased by four line periods, and
The signal 7a input to the input switching circuit 4 is delayed by four line periods, but the signal 9a input to the input switching circuit 4 is reduced by reducing the capacity of the subsequent field memory 8a by four lines. It can be the same as the signal 9 in the example. Other parts are the same as in the first embodiment.

[0026]

As described above, according to the present invention, the signal one field period before, which is supplied to the inter-field interpolation means for the color difference signal, is taken out from the signal path in the inter-frame interpolation means. Since no field memory is required for the color difference signal interpolating section,
This has the effect of reducing the circuit scale and cost.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main part of a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing details of an inter-field interpolation section 34a.

FIG. 3 is an explanatory diagram showing the operation of the selector.

FIG. 4 is a block diagram showing a main part of a second embodiment of the present invention.

FIG. 5 is a block diagram showing a main part of a conventional example.

FIG. 6 is a circuit diagram showing details of the inter-field interpolation unit 34;

[Explanation of symbols]

1, 46, 47 input terminal 2 MUSE signal 3 frame interpolation unit 4 input switching circuit 5, 7, 7a, 9, 9a, 12, 14, 16, 20, 2,
7, 29, 31, 33, 52 signal 6, 6a, 8, 8a, 51 field memory 10 luminance signal processing unit 11 two-line delay line (2H delay line) 13 pre-filter 15, 21, 44 frequency converter 17, 34, 34a Inter-field interpolation section 18 Inter-field interpolation signal 19 Inter-field interpolation section 22, 25, 35 Inter-field interpolation signal 23 Color difference signal processing section 24, 28, 32 Time extension section 26, 30 4 line delay line (4H Delay line) 36, 37 mixing circuit 38 luminance output signal 39 luminance output terminal 40 color difference output signal 41 color difference output terminal 42 motion detection unit 43, 45 motion detection signal 48 selector 49 terminal 50 output terminal

Claims (1)

(57) [Claims] 1. An interpolating means for interpolating an input high-definition television signal by a cyclic process using a field memory, and a high-definition television signal output from the interpolating means. Inter-field interpolation processing means for performing inter-field interpolation on the color difference signal, and field interpolation means for performing field interpolation, and output signals of the inter-field interpolation processing means and the field interpolation processing means And a mixing means for adaptively mixing the high-definition television signal based on the motion detection signal of the high-definition television signal. A high-definition television receiver comprising signal supply means for extracting and supplying the signal to the inter-field interpolation means.