JPH02278982A - Movement adaptive type luminance signal and chrominance signal separator - Google Patents

Abstract

PURPOSE:To control a pass band width of a variable vertical filter and a variable horizontal filter properly by using an output of a movement detection circuit, an output of a vertical change detection means and an output of a horizontal change detection means so as to designate an address of a storage device thereby reading a prescribed control signal. CONSTITUTION:An input of a control signal generating circuit 24' is an output signal K of a movement detection circuit 11, an output signal of a vertical change detection circuit 20 and an output signal of a horizontal change detection circuit 22. Then an address of a ROM is designated to read control data m'v, m'h stored in advance in response to the state of picture movement and a 2-dimension characteristic of the picture thereby controlling a variable vertical BPF 14 and a variable horizontal BPF 16. Since the vertical and horizontal filter is controlled nonlinearly depending on the output of the movement detection circuit, there is no visual sense of disorder from the moving state of the picture till the standstill state and the filter is controlled smoothly in response to the 2-dimensional characteristic of the picture thereby separating a luminance signal and a chrominance signal accurately.

Description

Detailed Description of the Invention [Industrial Application Field 1] The present invention relates to a luminance signal and chrominance signal separation device for separating and extracting a luminance signal and a color signal from a composite color television signal in equipment that handles images such as a telepinodine receiver. It flashes.

[Prior Art 1] Currently, the color television standard system generally used in television broadcasting etc. is a composite signal in which a luminance signal component and a color signal component are frequency-multiplexed. Therefore, in color television receivers and the like, it is necessary to separate and extract the luminance signal and color signal from the composite signal. Various methods have been developed to more accurately separate luminance signals and chrominance signals, and there are motion-adaptive luminance signal and chrominance signal separation processes that differ depending on whether the image is a still image or a moving image. This is a motion-adaptive type of processing that performs processing in the time axis direction in 7 frames of darkness when the image is still, and performs spatial processing (vertical and horizontal axes) within the field when the image is moving. high separation is possible. An example of this is JP-A No. 61-2744.
There is a "denotal decoder" described in Publication No. 93, which adaptively changes the intra-field processing for moving images depending on the spatial (two-dimensional) state of the image, and can produce relatively good luminance signals even in moving images. This allows separation of color signals.

In addition, prior to the present invention, the present applicant developed an improved motion-adaptive luminance signal color signal separation device and filed a patent application (Japanese Patent Application 1982-
No. 336121) and announced it at the Institute of Electronics, Information and Communication Engineers on May 25, 1986 (Proceedings of the 1986 IEICE National Conference, pp. 2-174 and Telepino Layer Society Technical Report, pp. 25-30). The structure of this improved motion-adaptive luminance signal/chrominance signal separation device is shown in FIG.
It is equipped with a temporal direction filter 13, a variable vertical filter 14, and a variable horizontal filter 16. It is possible to control the filter characteristics on the time axis, vertical axis, and horizontal axis to perform highly accurate separation of the luminance signal and color signal.

The control signal generating means for controlling the variable vertical filter 14 and the variable horizontal filter 16 is mainly constituted by a ROM whose address is specified by the output signal of the vertical change detection circuit 20 and the output signal of the horizontal change detection circuit 2Z. It consists of a control signal generation circuit 24 and multipliers 23 and 25 that multiply the output signal of the control signal generation circuit 24 by the output signal of the motion detection circuit 11.

As a result, the variable vertical filter 14 and the variable horizontal filter 16 are variably controlled according to the vertical and horizontal changes of the image, and are also variably controlled according to the movement of the image as shown in FIG. It is possible to separate the luminance signal and color signal.

[Problems to be Solved by the Invention] The tIIi control signal generation means in the improved motion adaptive luminance signal/chrominance signal separation device as shown in FIG.
The two output signals of the control signal generation circuit 24 are determined by the motion coefficient K, which is the output signal of the motion detection circuit 11, respectively.
The product output is used as a control signal.On the other hand, the output signal of this motion detection circuit 11 is processed by a temporal filter 13.
It is also used to control the mixing means that mixes the output signal of the variable vertical filter 14 with the output signal of the variable vertical filter 14, and the mixing ratio in this mixing means is the most appropriate for the output signal of the motion detection circuit. The standard value has been set as follows. In other words, the reference value for the motion coefficient is determined with priority given to this mixture ratio.

The multiplied output signals K my, K s+h of the signal generating means can only change linearly with respect to the motion coefficient K, as shown in FIG.

By the way, the output signal of this control signal generating means varies from the moving state of the image to the stationary state! ! There is no visual discomfort until
Moreover, since the variable vertical filter 14 and the variable horizontal filter 16 must be smoothly controlled according to the two-dimensional characteristics of the image, linear control using the motion detection output as in the conventional example is not sufficient.

Furthermore, when the multiplier is constructed using a dinotal circuit, there are disadvantages in that the circuit scale becomes large and the delay time determined by the characteristics of the elements is limited.

[Means for Solving the Problems 1] In the present invention, in order to solve the problems in the above-mentioned improved motion adaptive luminance signal/chrominance signal separation device, a predetermined control signal is recorded in the output signal of a control signal generation circuit. Instead of multiplying the output signal of the motion detection circuit, that is, the dynamic coefficient K, the storage device that constitutes this control signal generation circuit multiplies the output of the motion detection circuit, the output of the vertical change detection means, and the output of the horizontal change detection means. The address is specified by
The configuration is such that a predetermined control signal stored in advance is read out.

That is, according to the present invention, a motion detection circuit, a temporal filter, and a variable vertical filter each respond to a composite color signal, and a mixing ratio of the output of the temporal filter and the output of the vertical filter are determined in the motion detection circuit. a mixing means for mixing while changing in response to a signal indicating a detected image motion; a variable horizontal filter for separating color signals in response to the output of the mixing means; and a delayed signal of the combo knot color signal. means for subtracting the color signal to produce a luminance signal; vertical change detection means for detecting a difference at a sample point in the vertical direction of an image in response to the combo knot color signal; and a difference at a sample point in the horizontal direction of the image. and a horizontal direction change detection means for detecting the band of the variable vertical band filter and the variable horizontal band according to the output signals from the vertical direction change detection means and the horizontal direction change detection means and a signal indicating the motion of the image. In the motion-adaptive luminance signal/chrominance signal separation Wt device comprising a control signal generation means for generating a control signal for controlling a band of a filter, the control signal generation means has a storage device in which a predetermined control signal is stored in advance. 7 addresses of the storage device are designated by the output signal of the vertical change detection means, the output signal of the horizontal change detection means, and the output signal of the motion detection circuit, and the control signal is read out. Motion-adaptive luminance signal and color signal separation featuring the following! If! is provided.

[Operation 1] The motion-adaptive luminance signal/chrominance signal separation device of the present invention has a configuration in which the address of the control signal generation means for controlling the variable vertical filter and the variable horizontal filter is specified by the above three output signals. Therefore, it is possible to read out the two control signals by specifying addresses by taking into account not only the vertical and horizontal change detection results but also the motion coefficients. By storing a predetermined control signal in the vertical direction change,
The most appropriate control signal can be sent out based on the three factors: horizontal direction change and motion coefficient. As a result, it is possible to obtain a curvilinear change along a desired curve, rather than a linear change in the extra-motion coefficient of the control signal caused by the multiplication result with the motion coefficient in the conventional device, and the passage of the variable vertical filter and the variable horizontal filter. Bandwidth can be controlled most appropriately.

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

FIG. 1 is a block diagram showing an embodiment of a motion adaptive luminance signal/chrominance signal separation device of the present invention. A combo-not color signal converted into a digital signal by a ^/D converter (not shown) is applied to an input terminal 10, and is applied to a subtracter 18 via a delay compensation circuit IZ.

On the other hand, the composite color signal is processed by a motion detection circuit 11, a temporal band pass filter (BPF) 13, and a variable vertical BP.
It is given to F14. The output of the variable vertical BPF 14 is the subtracter 17, the multiplier 19, the adder 21 and the variable horizontal BP
The signal is applied to the signal output terminal 32 via the FI 6 and the color signal output terminal 32 of the 1.1s 18. The output of the reducer 18 is connected to a luminance signal output terminal 30. The composite color signal is further processed by a vertical change detection circuit 20 and a horizontal change detection circuit 22.
As will be described later, the difference at the vertical sample point and the difference at the horizontal sample point of the image in one field are detected, and a signal indicating this difference is provided to the control signal generating circuit 24'.

Further, the motion coefficient, which is the output signal of the motion detection circuit 11, is provided to a multiplier 19 and a control signal generation circuit 24'.

The control signal generation circuit 24° receives three input signals as 7dresses and generates two control signals m'v and m'h as described later.
are read out and given to the variable vertical BPF 14 and variable horizontal IPF 16 as band control signals, respectively. Note that the control signal generating circuit 24' constitutes a control signal generating means.

Next, the specific configuration and operation of each part will be explained. The motion detection circuit 11 has a 7-frame memory and detects the motion of an image by taking the difference between two consecutive frames of the same pixel of the image, and its output signal has a motion coefficient K ( Hereinafter, the output signal of the motion detection circuit 11 will be simply referred to as a motion coefficient, which indicates 0≦to≦1). It is one of the three inputs of the generator circuit.

The temporal direction BPF 13 cuts high-frequency components and low-frequency components with respect to image movement between two or more frames, and its output signal is sent to one terminal of the subtractor 17 and the ten terminal of the adder 21. Given.

The vertical change detection circuit 20 and the horizontal change detection circuit 22 detect changes in pixels in the vertical and horizontal directions in one field of images, and constitute vertical change detection means and horizontal change detection means, respectively.

FIG. 2 is a block diagram showing an example of a specific configuration of the control signal generating circuit 24'. For example, 4-bit data from the vertical change detection circuit 20, horizontal change detection circuit 22, and motion detection circuit 11 is applied to a latch 48, and is applied as a 12-bit addressing signal to a ROM (read-only memory) 50 for storage. If the control signal data is 8 bits, it is applied to the latch 52, and then two control signals of 4 bits each, 1'V%m'h, are read out, and the variable vertical BPF 14
and variable horizontal BPF1B, respectively.

In this way, the inputs of the control signal generation circuit 24' are the output signal of the motion detection circuit 11, the output signal of the vertical change detection circuit 20, and the output signal of the horizontal change detection circuit 22, and by these, the address of the ROM 50 is determined. The pre-stored control data m'V and m'l+ are read out according to the specified image movement state and the two-dimensional characteristics of the image, and optimize the variable vertical BPF 14 and variable horizontal BPF 16, respectively. It is possible to control the

This operation will be explained using FIG. 3. In the conventional example, as shown in FIG. 5, the variation range of the bandwidth of the variable vertical BPF 14 and the variable horizontal BPF 16 was linearly varied by the output signal K of the motion detection circuit 11.
In the present invention, the range of change in these bandwidths can be non-linearly changed by the output signal K of the motion detection circuit 11, as shown in Fig. MrJ3. This means that a desired curve can be formed, and therefore, the bandwidth of each variable band filter 14, 16 does not change much even with a slight movement of the H image, and dot interference etc. can be effectively suppressed. becomes possible.

Note that the control signal generation circuit is one ROM in the above embodiment.
However, it can also be divided into a plurality of ROMs depending on the number of input address bits and storage capacity.

[Effects of the Invention] As is clear from the detailed explanation above, the motion adaptive luminance/chrominance signal separation device according to the present invention can non-linearly control the vertical and horizontal filters using the output of the motion detection circuit. Therefore, from the state of movement of the iii image to the state of rest! ! The filter can be smoothly controlled according to the two-dimensional characteristics of the image, and the luminance signal and color signal can be separated precisely without any visual discomfort.

Furthermore, since the multiplier can be omitted, the circuit specifications can be reduced, and unnecessary time delays caused by the multiplier can also be eliminated.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the motion adaptive luminance signal/chrominance signal separation device of the present invention, FIG. 2 is a block diagram showing an example of the configuration of the control signal generation circuit in the fjfJ1 diagram, and FIG. FIG. 4 is a block diagram of a conventional motion adaptive luminance signal/chrominance signal separation device.
FIG. 5 is an explanatory diagram of the operating state of filter control in a conventional example. 11...Motion detection circuit, 12...Delay compensation circuit,
13... Time opening direction BPF, 14... Variable vertical B
PF, 16...Variable horizontal BPF, 17.18
...Three instruments, 19.23.25...Multiplier, 20
...Vertical change detection circuit, 21...Additional W, device, 2
2...Horizontal change detection circuit, 24.24゛...Control signal generation circuit, 48.52...Latch, 50...
ROM.

Claims (1)

[Claims] (1) A motion detection circuit, a temporal filter, and a variable vertical filter each responsive to a composite color signal, and an image in which the motion detection circuit detects the mixing ratio of the output of the temporal filter and the output of the vertical filter. a mixing means for mixing the color signal while changing it in response to a signal indicating the movement of the composite color signal; a variable horizontal filter for separating the color signal in response to the output of the mixing means; and a variable horizontal filter for separating the color signal from the delayed signal of the composite color signal. means for subtracting to produce a luminance signal; vertical change detection means responsive to said composite color signal, respectively, for detecting a difference at a sample point in a vertical direction of an image; and means for detecting a difference in a horizontal direction for detecting a difference at a sample point in a horizontal direction of an image. A change detection means, and a band of the variable vertical band filter and a band of the variable horizontal band filter are controlled according to output signals from the vertical change detection means and the horizontal change detection means and a signal indicating the movement of the image. In a motion-adaptive luminance signal/chrominance signal separation device comprising a control signal generating means for generating a control signal, the control signal generating means has a storage device in which a predetermined control signal is stored in advance, and the vertical change An address of the storage device is designated by an output signal of the detection means, an output signal of the horizontal change detection means, and an output signal of the motion detection circuit, and the control signal is read out. Adaptive luminance and chrominance signal separation device.