JP2008089943A - Storage structure for overdrive drawing data, and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the memory size of a drive controller of a display device making the most use of overdrive techniques. <P>SOLUTION: Drawing data are divided into non-video data and video data which are stored in a non-video data storage area and a video data storage area in a memory unit, respectively. Data of the primary colors of the non-video data are stored directly in the video data storage area, data of the primary colors of the video data are converted into YCbCr data, and current data of the primary colors and video data of the primary colors of the last image frame are compared to one another, by using a look-up table to obtain overdrive YCbCr data. Then the YCbCr data and overdrive YCbCr data are subjected to MPEG compression, sampled and combined, and stored in the video data storage area. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a data storage technique for display device images, and particularly to a graphic data overdrive storage device and method for reducing the need for storage memory size.

In recent years, liquid crystal display devices have gradually replaced CRT display devices due to the light and thin characteristics of liquid crystal display devices and further lower power consumption compared to conventional CRT display devices.

Liquid crystals are organic compounds that have intermediate properties between liquids and crystals, and change their color and transparency depending on voltage and temperature. The arrangement of the conventional liquid crystal display device includes a liquid crystal panel and a drive circuit connected to the liquid crystal panel, and the drive circuit includes a gray voltage for generating an electric circuit.

The liquid crystal panel is composed of a plurality of gates and a plurality of data lines connected to each other perpendicularly to the gates. Each pixel includes a thin film transistor (TFT), a capacitor, and a liquid crystal capacitor. Each pixel of the liquid crystal panel further includes three pixels corresponding to the three primary colors of red (R), green (G), and blue (B). The pixels displayed on the liquid crystal panel are composed of a combination of R, G, and B color filter lenses. Depending on the combination method, not only color drawings can be displayed, but also pure red, green, blue, and lightness can be displayed. Among them, the thin film transistor plays a role of a switching function, and its gate and gate line are electrically connected and controlled by a gate drive circuit. The source and data lines are also electrically connected and controlled by the source drive circuit. The gray voltage generates an electric circuit and is electrically connected to the source drive circuit to generate a gray voltage or a gray reference voltage, which is a reference for generating a liquid crystal drive voltage.

The operation method of the liquid crystal display device is that the gate drive circuit scans the pixels in each row of the panel in order, and the gray reference voltage generates the electrical circuit output at the gray reference voltage, and then the R input by the source drive circuit. A liquid crystal drive voltage is generated based on the G and B timing data. When the source drive circuit is activated, the liquid crystal drive voltage generated each time scanning is applied to the panel.

Due to the fact that liquid crystal display devices become faster with the development of the industry, the drive speed is increased to increase the charging speed of the storage capacitor and the liquid crystal capacitor in the pixel in the current system. If the voltage applied from the source drive circuit is a high value, the storage capacitor and the liquid crystal capacitor are quickly charged, and the total drive circuit performance of the liquid crystal display device is enhanced.

FIG. 1 is a schematic diagram of input / output gray voltages of overdrive. The output gray value 2 displayed by the pixels on the panel not only depends on the input gray value 1 of the original drawing data, but also uses the gray voltage of the previous frame, and can be calculated using a lookup table or conversion method. The output gray number 2 that causes overdrive is also used. Overdrive technology increases the gray value of the video data to accelerate the reaction time of the thin film transistor, making the screen smoother with a short reaction time. For example, the original input gray numerical data raises the panel brightness to 21 at 16.6 ms, but overdrive raises the panel brightness to 31 at 16.6 ms, thereby accelerating the thin film transistor reaction time and the liquid crystal inversion time. To make it even smoother.

With this overdrive technology method, the memory capacity of the drive element needs twice as much as the original, and the original picture data and the overdrive picture data are stored respectively. In a conventional method, a drive element generally used in a display device of a mobile phone is to add an external memory to the drive circuit by utilizing non-synchronization between graphic data input on a display screen and pixel scan. The overdrive graphic data can be stored in the external memory, the gray value of the original input graphic data is increased, the pixel reaction time is accelerated, and the screen is further smoothed.

Currently, this type of overdrive method requires an external memory to be added to the overdry circuit, which increases the memory capacity. However, this method has caused a great increase in demand for memory capacity of display device products, resulting in an increase in manufacturing cost and an increase in space required for the drive circuit.

In order to solve the above disadvantages and eliminate the disadvantages themselves, the present invention converts the three primary color data of the image data of the image frame data into YCbCr data, and converts the overdrive three primary color data into the overdrive YCbCr data. Both YCbCr data are compressed, sampled and combined by MPEG to reduce the memory cost of the display controller drive controller using overdrive technology.

  In order to achieve the above object, the present invention provides a data storage method of a drive controller for a display device, which divides drawing data into non-video data and video data, and a non-video data storage area in a memory unit. And the video data storage area. The three primary color data of the non-video data are stored directly in the video data storage area. The three primary color data of the video data is converted into YCbCr data, and the three primary color data of the previous video material is compared with the video data of the three primary colors of the image frame by a look-up table, and the three primary color data after comparison is converted into overdrive YCbCr data. Convert. Also, YCbCr data and overdrive YCbCr data are compressed, sampled and combined in MPEG and stored in the video data storage area.

The significance represented by Y is luminance, the significance represented by Cb and Cr is chrominannce, and the present invention uses the sampling of the Y component that has the greatest effect on the human eye. Proportionally sampled and compressed, then stored in the memory module, the drive controller reduces the size required for the memory unit.

  In order to realize the system according to the present invention, the storage structure in the drive controller of the display device is changed. The storage structure according to the present invention includes a memory unit, which is divided into a non-video data storage area and a video data storage area. The first multiplexer has two input terminals, and the input terminals are connected to non-video data of the three primary colors (RGB) of the image frame and output the data to the non-video data storage area. The first conversion unit is connected to video data of the three primary colors (RGB) of the current image frame (frame N) and converts the three primary color data into YCbCr data. Further, the second conversion unit compares the video data of the three primary colors of the current image frame (frame N) and the previous image frame (frame N-1) by using a lookup table, and then the overdrive three primary colors (R The data of “G′B”) is converted into overdrive YCbC r data (Y′Cb′C r ′). The data code unit connects the YCbCr data output from the first conversion unit and the overdrive YCbCr data output from the second conversion unit, compresses, samples, and combines the two data using MPEG. The signal is input to the other input terminal of the multiplexer and transmitted to the video data storage area through the first multiplexer. In the compression and sampling, the calculation rule is sampled from any one of Y: Cb: Cr = 4: 2: 2, Y: Cb: Cr = 4: 2: 0 and Y: Cb: Cr = 4: 1: 1.

  The image data of the three primary colors of the image frame (frame N-1) are YCbCr data and overdrive YCbCr data of the previous image frame in the image data storage area, and are decompressed by the previous original MPEG through the data code unit, and further The YCbCr data is converted into video data of the three primary colors of the previous frame through the first conversion unit and transmitted to the lookup table.

  The storage data of the memory unit is connected to the data of the non-video data storage area through the input terminal of the second multiplexer, and the decompression unit converts the data of the video data storage area into data of the three primary colors, The second multiplexer outputs the non-video data and the video data to the display element.

The overdrive graphic data storage structure allows overdrive technology to reduce memory needs.

The detailed contents and technical description of the present invention will be described as follows together with the diagram.
This is because the various colors seen by the human eye have different wavelengths in the light. Through experimentation, the human eye is particularly sensitive to the three wavelengths, and the intensity of these three types of light is measured. It was discovered that, with proper adjustment, humanity can feel almost all colors. These three colors are called the three primary colors of light (RGB), namely red, green and blue. All color televisions and screens are equipped with light emitting devices that generate these three basic light beams. Since almost all colors can be displayed by mixing these three types of light, the computer displays the colors in the size of the digital data values of the three primary colors (RGB), and each color is recorded in 8 bits. In total, 256 types of luminance changes are possible. When the three types are multiplied, there are about 16 million variations, which is the 24-bit all color that we often hear.

The Y data of YCbCr data is the color converted to the gray value or luminance value of the gray image, and this conversion formula has different sensitivity mainly for the three primary colors (RGB) of red, green and blue. In particular, the larger the numerical value, the more sensitive the human eye is to the above-mentioned colors, so the sensitivity of the three colors is green (0.587), red (0.299), blue (in order) 0.114). For this reason, the general conversion calculation relationship in which the three primary color (RGB) data is converted to YCbCr data is as follows.
Y = 0.299R + 0.587G + 0.114B
Cb = −0.168R−0.331G−0.499B
Cr = 0.500R-0.419G-0.081B
The relationship of conversion calculation for converting YCbCr data to three primary color (RGB) data is as follows.
R = Y + 104020 (Cr-128)
G = Y-0.3441 (Cb-128) -0.7141 (Cr-128)
B = Y + 107720 (Cb−128)

For the human eye, data for low frequencies is more sensitive than data for high frequencies, but in fact the human eye is much more sensitive to changes in brightness than changes in color. Therefore, in terms of application of display devices, generally only gray and all color images are processed, and all color images are composed of combinations of Y, Cb, and Cr three-component components. Since a gray video has only luminance and no color, there is only one element, Y data. The meaning represented by Y data is luminance, and the meaning represented by Cb and Cr is hue data, that is, Y data is important.

FIG. 2 is a schematic view of a storage structure according to the present invention. The present invention is mainly based on the above principle, and presents the above storage structure. However, the present invention is a storage structure in a drive controller installed in a display device, and includes a memory unit 15. The internal area is divided into a non-video data storage area 151 and a video data storage area 152. The input end is connected to the non-video data of the three primary colors (frame N) of the current image frame through the first multiplexer 11 having two input ends, and the data is output to the non-video data storage area 151. The other input terminal receives the converted and combined video data and transmits the video data to the video data storage area 152 of the memory unit 15.

The video data is first transmitted to the first conversion unit 131 before being stored, and the first conversion unit 131 is connected to the video data of the three primary colors RGB (frame N) of the current image frame, and the three primary color RGB data is YCbCr data. Converted to
The second conversion unit 132 compares the original video data of the three primary colors of the current image frame and the previous image frame using the lookup table 12, and uses the overdrive YCbCr data as the overdrive three primary color data R'G'B '. Convert to Y'cb'Cr '. Then, the data code unit 141 connects the YCbCr data output from the first conversion unit 131 and the overdrive YCbCr data Y'cb'Cr 'output from the second conversion unit 132, and both the data are MPEG (Motion Pictures Expert Group). ) To compress, sample and combine, Y: Cb: Cr = 4: 2: 2, Y: Cb: Cr = 4: 2: 0 and Y: Cb: Cr = 4: 1: 1 Sampling rules from either. The combined data is input to the other input terminal of the first multiplexer 11 and transmitted to the video data storage area 152 through the first multiplexer 11.

The video data of the three primary colors of the previous frame (frame N-1) is the original YCbCr data of the previous frame in the video data storage area 152, which is decompressed by the original MPEG through the decode unit 142, and is converted by the third conversion unit 133. Convert YCbCr data to video data of the three primary colors of the previous frame.

FIG. 3 is a schematic diagram in which the graphic material is divided into non-video and video data. The non-video data storage area 151 in the memory unit 15 stores the non-video three primary colors R, G, and B of the original image frame. The video data storage area 152 stores YCbCr data compressed and sampled in the original video data of the current image frame, and overdrive YCbCr data Y ′ Cb′Cr ′ compressed and sampled after overdrive. When Y: Cb: Cr = 4: 1: 1 (4: 2: 0) is sampled and compressed, it is the original compressed and sampled YCbCr data, and a set of CbCr data consists of four pixels Used for Y data, the data is stored before that, another overdriven YCbCr data Y 'Cb'Cr' is a set of Cb'Cr 'data consisting of 4 pixels Y' data The data is subsequently saved afterwards.

FIG. 4 is a schematic diagram of video data storage according to the present invention. Taking 4x4 pixels of the display device as an example, the video data of the original image frame is sampled and compressed in Y: Cb: Cr = 4: 1: 1 (4: 2: 0), and then the video data storage area There are 152 original compressions, sampled YCbCr data as well as 4 post-drive compressed, sampled YCbCr data Y'cb'Cr '. Therefore, in addition to the four original compressed and sampled YCbCr data stored in the video data storage area 152, the four overdriven YCbCr data Y'cb'Cr 'are also stored and overwritten with the original data. By simply compressing and sampling the driven data, it increases the gray value of the video data, thereby accelerating the thin film transistor (TFT) reaction time and liquid crystal inversion time, making the screen smoother. is there.
At the same time, the original data and overdriven data are also compressed and sampled, reducing the need for memory for the display controller's drive controller using overdrive technology and reducing the cost of the memory.

The data stored in the memory unit 15 is further connected to the three primary color (RGB) data in the non-video data storage area 151 through the input terminal of the second multiplexer 17, and the decompression unit 16 converts the YCbCr data in the video data storage area 152 into the three primary colors. The data is converted into (RGB) data, output to the input terminal at the other end of the second multiplexer 17, the data and video data in the non-video data storage area are scanned and output through the second multiplexer 17, and the display element 20 Forward to.

The present invention presents a method for storing overdrive graphic data. The method according to the present invention divides graphic data into non-video data and video data, and also includes a non-video data storage area 151 and video data in the memory unit 15. The data is stored in the storage area 152, respectively. The three primary color (RGB) data of the non-video data is directly stored in the video data storage area 151, and the three primary color data of the video data is converted into YCbCr data. The three primary color video data of the previous image frame are compared, and the three primary color data after the comparison are converted into overdrive YCbCr data Y'cb'Cr '. Next, the YCbCr data and the overdrive YCbCr data are compressed, sampled and combined by MPEG and stored in the video data storage area 152.

Taking an image frame of 4 × 4 sets of three primary color RGB data as an example (shown in FIG. 4), in the conventional overdrive model, the memory capacity is the original 16 × 3 = 48 bits and the original three primary color RGB data is stored. In addition, it is necessary to store data of the three primary colors R'G'B 'that has been overdriven with a memory capacity of a similar size (16 x 3 = 48 bits). 2 times the memory capacity, and is stored in original image data (original image data) and overdrive image data (overdrive image data), respectively, and the graphic data of overdrive technology is stored with a total of 96 bits.

In the present invention, the three primary color (RGB) data conversion is first converted into YCbCr data, and then Y: Cb: Cr = 4: 2: 2 (2: 1: 1) or Y: Cb: Cr = 4: 1: 1 (4 : 2: 0) proportionally sampled or sampled as compressed. Taking sampling and compression of Y: Cb: Cr = 4: 1: 1 (4: 2: 0) as an example, the four Y data of the present invention share the same set of Cb and Cr data. The overdriven graphic data (Y′cb′Cr ′) also shares the same set of Cb ′ and Cr ′ data with the four Y ′ data. Therefore, as shown in FIG. 4, the size required for storing the overdrive video data according to the present invention suffices with a 48-bit memory space similar to the non-overdrive model. Compared to the drive model, it saves half of the storage space.

The present invention converts the original three primary color data and the overdrive three primary color data of the video data in the drawing data into YCbCr data format, compresses and samples with MPEG, and further saves them in the memory of the drive controller of the display device. This effectively reduces the need for storage, reduces the need for storage space for overdrive model memory, and saves overdriven graphic data in the original memory space, thereby reducing production memory costs. .

The above description is only a preferred embodiment of the present invention, and does not limit the scope of the present invention. In other words, uniform changes or modifications made within the scope of patents for which the present invention is applied are all within the scope of the technology according to the present invention.

It is the schematic of the input-output gray voltage of an overdrive. It is the schematic of the preservation | save structure which concerns on this invention. It is the schematic which divided the drawing material into the non-video and video data. It is the schematic of video data preservation | save based on this invention.

Explanation of symbols

11 First multiplexer 12 Look-up table 131 First conversion unit 132 Second conversion unit 133 Third conversion unit 141 Data code unit 142 Data decoding unit 15 Memory unit 151 Non-video data storage area 152 Video data storage area 16 Decompression unit 17 Two multiplexer 20 display element

Claims (6)

A storage structure for overdrive graphic data, which is a storage structure installed in the drive controller of the display device,
A memory unit including a non-video data storage area and a video data storage area;
A first multiplexer having two input ends, one input end being connected to non-video data of the three primary colors of the image frame, and outputting the data to the non-video data storage area;
A first conversion unit that connects to the video data of the three primary colors of the image frame and converts the data of the three primary colors into YcbCr data.
A second conversion unit that compares the video data of the three primary colors of the current image frame and the previous image frame with a lookup table, and then converts the data of the three primary colors into overdrive YCbCr data;
The YCbCr data output from the first conversion unit and the overdrive YCbCr data output from the second conversion unit are connected, both data are compressed, sampled and combined by MPEG, and the combined data is input to the other input of the first multiplexer. An overdrive graphic data storage structure comprising a data code unit that is input to an end and transmitted to the video data storage area through the first multiplexer. The video data of the three primary colors of the previous frame is the original YCbCr data of the previous frame in the video data storage area, decompressed by the original MPEG through the data decoding unit, and the YCbCr data of the previous frame by the third conversion unit 2. The overdrive graphic data storage structure according to claim 1, wherein the data is converted into video data of three primary colors. Connecting the storage data of the memory unit to the data of the non-video data storage area through an input terminal of a second multiplexer;
The decompression unit decompresses the data in the video data storage area, converts it into three primary color data, outputs it to the input terminal at the other end of the second multiplexer, and displays the data and video data in the non-video data storage area through the second multiplexer. 2. The overdrive graphic data storage structure according to claim 1, further comprising a step of transferring to the element. In the compression and sampling, the operation rule is sampled from any of Y: Cb: Cr = 4: 2: 2, Y: Cb: Cr = 4: 2: 0 and Y: Cb: Cr = 4: 1: 1. The overdrive graphic data storage structure according to claim 1, wherein: An overdrive graphic data storage method for storing the drive controller data of the display device. The graphic data is divided into non-video data and video data, which are stored in the non-video data storage area and video data storage area in the memory unit. Storing the three primary color data of the non-video data directly in a video data storage area;
The three primary color data of the video data is converted into YcbCr data, and the three primary color data of the video data is compared with the three primary color video data of the previous image frame by using a lookup table, and the three primary color data thus compared are compared. A method for storing overdrive drawing data, comprising: converting the YCbCr data into overdrive YCbCr data, compressing, sampling and combining the YCbCr data and overdrive YCbCr data with MPEG, and storing the data in a video data storage area. In the compression and sampling, the operation rule is sampled from any of Y: Cb: Cr = 4: 2: 2, Y: Cb: Cr = 4: 2: 0 and Y: Cb: Cr = 4: 1: 1. 6. The method for storing overdrive drawing data according to claim 5, wherein:

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