KR101552886B1 - Apparatus and method of improving definition of moving picture - Google Patents

Abstract

The present invention relates to an apparatus and a method for improving the picture quality of a moving picture. More particularly, the present invention relates to an apparatus and a method for improving picture quality of a moving picture, The present invention provides a method for improving the quality of a moving image that can correct luminance of a pixel to be determined and transmit the corrected luminance to a liquid crystal display device.

Video, brightness, picture quality

Description

[0001] APPARATUS AND METHOD OF IMPROVING DEFINITION OF MOVING PICTURE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for improving picture quality of a television, and more particularly, to an apparatus and a method for improving picture quality of a moving picture.

Display devices for replacing the difficulty of miniaturization of CRT (Cathode Ray Tube) have been studied for a long time, and liquid crystal display (LCD) has been regarded as a display device having the most advanced technology capable of replacing it.

However, a liquid crystal display capable of solving the problems of miniaturization and weight of a CRT has a problem in afterimage, contrast ratio, response speed, etc. Such problems are gradually being improved through continuous research in the field of liquid crystal display devices.

Among them, blurring phenomenon (or afterimage) of a moving image is pointed out as a major problem of a liquid crystal display device, and various methods for improving the blurring phenomenon have been proposed.

Conventional techniques for eliminating motion blur in video include techniques for controlling the backlight. That is, a backlight scanning method in which the CCFL backlight is sequentially turned on or off, or a backlight blinking method in which the entire backlight is turned off for each frame for a predetermined time is used.

In addition, methods of controlling only the CCFL corresponding to a region in which a moving picture exists are analyzed by advancing the backlight scanning technique as described above to analyze the data of the entire screen. Due to such a method, blurring phenomenon It has been removed and a smoother screen can be output.

However, the conventional techniques for controlling the backlight for improving the image quality of the moving picture have a problem of reducing the brightness of the liquid crystal display device. That is, since the conventional technique repeatedly turns on and off the backlight, the luminance is seriously reduced.

Particularly, in the case of the backlight scanning method in which the backlight is sequentially turned on, the number of backlights always turned on is reduced by 1/4 as compared with the general driving method, and the total luminance of the liquid crystal display is also reduced to 1/4, and flicker phenomenon And the like. In order to solve the above problem, there is a problem in that a method of blinking only a CCFL corresponding to a part in which a moving image exists is improved to some extent as compared with the conventional method, but a reduction in partial or overall luminance can not be avoided .

That is, a conventional technique of scanning or blinking a backlight to improve the quality of a moving image has a problem in that the overall luminance of the liquid crystal display device is lowered.

In order to solve the above problems, an object of the present invention is to provide a method and apparatus for analyzing data for each frame for a broadcast program received on a television, A method of improving picture quality of a moving picture capable of correcting luminance of a picture element and transmitting the picture to a liquid crystal display device.

According to another aspect of the present invention, there is provided an apparatus for improving the moving picture quality of a television, comprising: a signal processing unit for processing a broadcast signal received by the television and separating the received signal into a voice signal and a video signal; Th frame and the (n + 1) -th frame to detect a moving picture pixel region in which a pixel value changes, and adjusts a pixel data value for the detected moving picture pixel region, And a conversion unit for correcting the luminance lower than the original luminance.
According to another aspect of the present invention, there is provided a method for improving the moving picture quality of a television, comprising the steps of: separating a video signal and a video signal from a broadcast signal received by the television in a signal processing unit of the television; Frame and an (n + 1) -th frame; comparing the n-th frame with the (n + 1) -th frame in the converting unit to determine whether a moving picture pixel region in which a pixel value is changed exists; As a result, if the moving picture pixel region exists, the converting unit adjusts the pixel data value for the moving picture pixel region of the (n + 1) -th frame to correct the luminance of the moving picture pixel region to be lower than the original luminance, After the correction step, the (n + 1) -th frame and the (n-1) Quot;

The present invention relates to a method and an apparatus for analyzing data for each frame for a broadcast program received on a television to regard a portion where pixel data changes as a moving picture pixel region and modulate a luminance for a pixel determined as a moving picture pixel region, The image quality of the moving image outputted through the liquid crystal display device can be improved, and the decrease in luminance of the liquid crystal display device can be minimized.

In other words, the present invention is a solution to the response speed of moving picture, which is one of the problems of the liquid crystal display constituting the television, by modulating the luminance for the pixel where the change will occur, So that there is an excellent effect.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of a television according to an embodiment of the present invention.

Recently, digital broadcasting systems using digital television have been developed. As one of such digital broadcasting systems, a digital broadcasting system using an Internet Protocol (IP) network has been used.

In addition, a television (recording function television) equipped with a personal video recorder (PVR) function that automatically records and reproduces a broadcast on a built-in storage unit (HDD: hard disk drive) Has recently become widespread.

Meanwhile, a method for improving the picture quality of a moving picture according to the present invention can be applied not only to a digital television but also to an analog television. However, in order to compare each frame of a video signal with each other, a lookup table related to correction of data and pixels of each frame is stored It is desirable to apply the present invention to a digital television equipped with a storage unit as described above.

1, the television to which the present invention is applied includes a channel tuning unit 410, a signal processing unit 420, a liquid crystal display 430, a speaker 440, a data storage unit 450, an interface 460 A user selection unit 470, a conversion unit 480, and a control unit 490.

The channel tuning unit 410 may include one or a plurality of tuners for tuning a broadcast signal received through an antenna and a demodulator for outputting the tuned signals in a transport stream format through a demodulation process and an error correction process , The broadcasting signal having the frequency band corresponding to the tuning control signal of the control unit is tuned.

The signal processor 420 processes the broadcast signal of the channel tuned through the channel tuner and separates the broadcast signal into a voice signal and a video signal, and then transmits the voice signal to the speaker and the video signal to the converter.

The conversion unit 480 compares the video signal transmitted from the signal processing unit on a frame-by-frame basis to convert the luminance of the moving picture pixel region including the moving picture, and transmits the video signal including the converted luminance to the liquid crystal display . On the other hand, a television generally outputs a continuously converted video signal. The term moving picture used in the present invention is used as a relative concept representing an image that is dynamically converted more dynamically than other parts of dynamically converted video signals . For example, when a soccer broadcast program is relayed on a television, a soccer broadcast video signal is a video signal in which the entire screen moves dynamically. In general, a soccer ball is almost stationary, In the soccer broadcast program, when the entire signal of the image portion output to the liquid crystal display device is a video signal, the moving part of the video signal, especially the soccer players, can be referred to as a moving picture. On the other hand, a frame refers to a still image constituting a video signal, and a large number of frames are combined to complete a video signal. In addition, the moving picture pixel region refers to a pixel region constituting a moving picture among one frame, and frames including the moving picture pixel region are continuously output, thereby outputting a moving picture from the video signal.

The liquid crystal display device 430 outputs a video signal transmitted from the converting unit of the selected channel so that the user can view the video signal. The liquid crystal display 430 may be a digital light processing (DLP), a liquid crystal display (LCD) Plasma Display Penal) and the like can be applied. 1, the liquid crystal display includes an interface circuit 431, a timing controller 432, a gate driver 433, a source driver 434, an LCD panel 435, an inverter 436, And a light 437. The interface circuit generates various signals such as a vertical synchronizing signal (Vsync), a horizontal synchronizing signal (Hsync), a data enable signal, and a data clock signal in response to the supply of the video signal from the converting unit And the timing controller generates a control signal required for the gate driver and the source driver based on a signal provided from the interface circuit and provides the control signal to the gate driver and the source driver. The gate driver supplies scan pulses of a gate high voltage to the gate lines sequentially according to a gate shift clock (GSC) provided from the timing controller to allow data to be charged in a liquid crystal cell of the LCD panel, Latches data according to a shift clock (SSC), a source start pulse (SSP), etc., provided from the timing controller, and provides the data to the source line. The gate lines are sequentially driven to turn on the thin film transistors of the LCD panel. At the same time, the data latched through the source line is charged in the LCD panel. At this time, due to the voltage difference between the pixel electrode and the common electrode Predetermined information is displayed while the liquid crystal cell is variable.

The speaker 440 outputs a voice signal decoded by the signal processor of the broadcast signal of the selected channel so that the user can hear the voice signal.

The data storage unit 450 includes a hard disk drive and the like. The data storage unit 450 stores a broadcast signal and EPG information received from the channel tuning unit, and stores a lookup table to be used in the conversion unit. do. That is, the look-up table refers to related information for correcting the luminance of the moving picture pixel region. For example, the converting unit may calculate the luminance of the moving picture pixel region by using the variation of the moving picture pixel region and the current luminance of the moving picture pixel region. The luminance of the current moving picture pixel area is corrected by referring to the lookup table indicating whether to change the current moving picture pixel area.

The interface 460 is connected to a network and a personal computer (PC), and transmits / receives various broadcast signals and content information.

The user selection unit 470 includes various menu buttons for controlling the control unit. The user selection unit may include at least one of a remote signal receiving unit for receiving the remote control signal transmitted from the remote controller or an input pad unit including buttons formed on the television outer surface. And various buttons such as a bar.

The control unit 490 is realized by a CPU or a microcomputer. The control unit 490 not only outputs a broadcasting program among broadcasting signals transmitted through a channel tuning unit through a speaker and a liquid crystal display, but also converts information of a lookup table into a conversion unit Or temporarily store the frame data transmitted from the conversion unit in the storage unit.

FIG. 2 is a flowchart illustrating an image quality improvement method of a moving image according to the present invention. FIG. 3 is a diagram illustrating a conversion state of a frame for explaining a method of improving image quality of a moving image according to the present invention.

The method of improving picture quality of a moving picture according to the present invention aims at improving picture quality in a video signal in which a change such as a moving picture is severe due to characteristics of a liquid crystal display device of a hold type driving system, A method of finding the changing pixels and lowering the luminance by a predetermined value is used.

To this end, the method for improving the quality of moving images according to the present invention starts with a process of temporarily storing the n-th frame and the (n + 1) -th frame of the video signal transmitted from the signal processing unit in the data storage unit. At this time, the conversion unit may store data of the n-th frame and the (n + 1) -th frame in the data storage unit, but may store the data in the storage unit formed in the conversion unit itself.

Then, the converting unit compares the (n + 1) th frame with the (n + 1) th frame and determines whether there is a pixel region having data different from the pixel of the n-th frame among the pixels of the (n + 1) -th frame. For example, as shown in Fig. 3, when a video signal that the car runs on the road is received by the television, the video signal is represented by the n-th frame, the (n + 1) (N + 1) -th frame is compared with the n-th frame, it can be seen that only the pixel region (hereinafter simply referred to as' moving image pixel region ') of the portion A and A' In the above description, only the n-th frame and the (n + 1) -th frame are stored and the two frames are compared. However, the present invention is not limited thereto. That is, the present invention may be configured to store at least two frames in consideration of the processing capability and speed of the conversion unit, and sequentially select the moving picture pixel region by comparing the forward and backward frames. Therefore, the television to which the present invention is applied has a delay time of at least one frame or more than a general television.

As a result of the determination, when it is determined that the moving picture pixel region A 'exists among the pixels of the (n + 1) -th frame, the transforming unit uses the lookup table stored in the data storing unit (206) with the pixel data having the luminance. That is, the present invention is for improving the image quality of a moving image. To this end, the present invention uses a method of lowering the brightness of pixels of a moving image pixel region. On the other hand, in the frames as shown in FIG. 3, a certain amount of change can be detected not only in the moving picture pixel area in which the car is represented, but also in other areas, except when the camera is completely stopped. However, the present invention is intended to reduce the luminance of a moving picture pixel area having a larger amount of variation than other moving pictures, and the converting unit may extract a plurality of moving picture pixel areas in one frame in consideration of the luminance. In this case, it is difficult to predict the amount of change of the moving picture with only two frames. To this end, according to the present invention, the moving picture pixel region having the largest change amount or a change amount exceeding a certain limit is extracted .

The reason why the present invention reduces the luminance of the moving picture pixel region as described above is to reduce the blur phenomenon in the moving picture. That is, in order to improve the blurring phenomenon of the liquid crystal display device, conventionally, a method for improving only the response speed of the liquid crystal has been proposed. However, since the LCD is a hold-type driving mode, a residual image remains in the human visual system independent of the response speed. The afterimage remaining in the human visual system depends on the amount of light energy, and the larger the light energy, the more the afterimage remains in the human eye. A simple example is that when you expose your eyes to bright light like the sun, you will still have a blurred image when you look at other objects for a while. This is because sunlight with a large amount of light energy comes into your eyes and affects the human visual system. Unlike a CRT in a liquid crystal display device, a pixel holds data for one frame to transmit light having a constant brightness, so that much energy is left in human vision as compared with an impulse type CRT. Accordingly, the present invention uses a method of reducing the blurring phenomenon by reducing the light energy of the moving image by reducing the luminance of the moving image pixel regions where the image is changed. In the meantime, the present invention is not performed in the liquid crystal display device 430, but in the preceding stage of the liquid crystal display device, that is, in the conversion part. The liquid crystal display device according to the present invention has hardware and software variations It becomes unnecessary.

The conversion unit temporarily stores the corrected n + 1-th frame and the n-th frame after correcting the luminance of the moving picture pixel area as described above (208). After a predetermined time elapses, And transmitted to the liquid crystal display device (210). If it is determined that there is no moving picture pixel area among the pixels of the (n + 1) -th frame, the transformer also temporarily stores the n-th frame and the (n + 1) . Storing and storing the compared frames as described above is for continuously transmitting frames to the liquid crystal display 430. For example, if the (n + 1) -th frame is corrected or is not corrected by transmitting the n-th frame to the liquid crystal display after the determination 204, The (n + 1) th frame can not be directly transmitted to the liquid crystal display device for comparison with two frames, so that a delay time between each frame occurs and the screen may flicker.

That is, according to the present invention as described above, the received data of the n-th frame and the (n + 1) -th frame are temporarily stored and then the two frames are compared with each other. Data is directly transmitted to the liquid crystal display device and output. When a difference occurs, the data is modulated by referring to a lookup table prepared only for the corresponding pixel of the (n + 1) th frame. To this end, the look- Is stored in the data storage unit or the conversion unit in advance.

On the other hand, in the case of a liquid crystal display device driven at 60 Hz or more, even in a moving image at a high speed, the difference between two adjacent frames is not large. Therefore, even if the brightness of the pixels having the difference is lowered as in the present invention, the overall brightness of the liquid crystal display device is not significantly affected.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

1 is a block diagram of a television according to an embodiment of the present invention;

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

DESCRIPTION OF THE RELATED ART [0002]

410: channel tuning unit 420: signal processing unit

430: liquid crystal display device 440: speaker

450: Data storage unit 460: Interface

470: User selection unit 480:

490:

Claims (9)

An apparatus for improving the moving picture quality of a television, A signal processor for processing the broadcast signal received by the television and separating the broadcast signal into a voice signal and a video signal; A moving picture pixel region in which a pixel value is changed is detected by comparing the nth frame and the (n + 1) th frame of the video signal applied from the signal processing unit, and a pixel data value is adjusted for the detected moving picture pixel region, and a conversion unit for correcting the luminance of the moving picture pixel region of the (n + 1) -th frame to be lower than the original luminance, The conversion unit corrects the luminance of the moving picture pixel region according to the lookup table with reference to a lookup table storing information on the current luminance of the moving picture pixel region in advance when the moving picture pixel region is detected And the image quality improvement device of the moving image. The method according to claim 1, Wherein, And the pixel data of the n-th frame and the (n + 1) -th frame are not converted when the moving picture pixel area in which the pixel value of the comparison result of the n-th frame and the (n + 1) And the image quality improvement device of the moving image. delete The method according to claim 1, Wherein, And temporarily stores the (n + 1) -th frame, which has been corrected or not corrected, with the n-th frame for a predetermined period of time before outputting the pixel-corrected n + 1-th frame. The method according to claim 1, Wherein, And the (n + 1) -th frame and the (n-1) -th frame in which the luminance is corrected are transmitted to the liquid crystal display of the television. A method for improving the moving picture quality of a television, Separating a video signal and a video signal from a broadcast signal received from the signal processing unit of the television through the television; Storing an n-th frame and an (n + 1) -th frame of the video signal in a conversion unit of the television; Comparing the n-th frame and the (n + 1) -th frame in the converting unit to determine whether a moving picture pixel area in which a pixel value changes exists; As a result of the determination, if the moving picture pixel region exists, the converting unit adjusts the pixel data value for the moving picture pixel region of the (n + 1) -th frame to correct the luminance of the moving picture pixel region to be lower than the original luminance Wow, And outputting the (n + 1) -th frame and the n-th frame, the luminance of which has been corrected by the conversion unit, to the liquid crystal display of the television after the correcting step, Wherein the correcting step is a step of correcting the luminance of the moving picture pixel region according to the lookup table with reference to a lookup table storing information on the current luminance of the moving picture pixel region in the converting unit in advance How to improve the quality of moving pictures. The method according to claim 6, Further comprising the step of not converting the pixel data of the n-th frame and the (n + 1) -th frame in the conversion unit when the moving picture pixel area does not exist as a result of the determination . delete The method according to claim 6, And the step of temporarily storing the (n + 1) -th frame, which has been corrected or not corrected, with the n-th frame for a predetermined period of time before the converting unit outputs the pixel-corrected n + Wherein the image quality of the moving image is improved.

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