KR100519763B1 - Method and apparatus for rendering image signal - Google Patents

Abstract

The present invention discloses a method for representing an image in an image presentation device having a plurality of pixels including a plurality of subpixels. A method of representing an image in an image display apparatus including subpixels displaying four or more different colors, each pixel including three subpixels of (a) 4 Selecting three color signals according to types of subpixels constituting a predetermined pixel among the one or more color signals; (b) obtaining selected color signal values of peripheral pixels of the pixel; (c) calculating a brightness value to be expressed in each subpixel included in the pixel by using the selected color signal value and corresponding color signal values of the peripheral pixel; And (d) driving the display to control the brightness of the image to be expressed in the image display device according to the calculated subpixel brightness value.

Description

Method and apparatus for expressing image signal

The present invention relates to a method and apparatus for representing an image. Specifically, the present invention relates to a method of expressing an input image while minimizing deterioration of image quality when the resolution of the input image signal is higher than the resolution of the image display apparatus, and an image expression apparatus using the method.

When the actual number of pixels of the image display apparatus is smaller than the number of pixels of the input image signal, that is, when the spatial resolution of the input signal is larger than the resolution of the image display apparatus, the image signal is displayed to display the entire area of the input signal on the image display apparatus. Down sampling should be done. However, downsampling of an image signal generates jagged patterns in an image portion (e.g., text, line, and edge) having a high spatial frequency (hereinafter, referred to as aliasing), which is an image displayed on an image display device. Is one of the causes of deterioration of the image quality.

As a conventional method for solving this problem, an anti-aliasing method for pixels is introduced in Computer Graphics: Principles and Practice 2nd [Foley et al., Addison-Wesley, 1996]. The proposed method reduces the difference in brightness values between neighboring pixels by performing low pass filtering on the image signal, smoothing the image signal, and sampling, thereby reducing coarse image phenomena such as jagged patterns. This method uses low pass filtering to reduce the difference between the values between pixels, and thus, the contrast effect of the image is weakened, thereby causing the blurring of the image sharply.

One of methods of controlling object and character boundaries in units of sub-pixel (RGB component) instead of pixel processing is disclosed in US Patent No. 6,384,839 filed by Agfa Monotype Co. This method improves the sharpness of the image by sub-pixel boundary processing, and also mitigates the brightness difference between adjacent pixels, thereby reducing color fringe error caused by sudden color transition at the object boundary during sub-pixel processing. Reduced. In this method, in order to obtain weights to alleviate the difference in brightness between pixels near the boundary, the image is first divided into the foreground and background areas, and then the object and background areas are binarized. The low-pass filtering of the binarized images was performed to obtain the weight of the whole image area.

However, this method uses only a horizontal lowpass filter for applying the RGB stripe type in the horizontal direction, and performs one-to-one conversion for each pixel, so that the same channel (subpixels of the same primary color) must be arranged in the vertical direction. It is not suitable for the channel image display apparatus, and there is no disclosure on the processing method when the image resolution is different from the device resolution, that is, scaling.

The technical problem to be achieved by the present invention is an image representation that increases the apparent resolution of the image display device by using different spatial arrangement of sub-pixels, when the spatial resolution of the image display device is lower than the spatial resolution of the input image signal It is to provide a method and apparatus.

In particular, in a color image display device using four primary colors and having a limited spatial resolution, color space by subpixel position is performed by using different spatial arrangements of four primary colors of subpixels, and thus the apparent spatial resolution in the four primary color image display devices. It is to provide an image expression method and an image expression apparatus for increasing.

In order to achieve the above-described technical problem, a subpixel for displaying each of at least four different colors, and including an image display device including a pixel composed of three different subpixels among the subpixels. The method comprises the steps of: (a) selecting three color signals in accordance with the type of subpixels constituting a predetermined pixel among four or more color signals; (b) obtaining selected color signal values of peripheral pixels of the pixel; (c) calculating a brightness value to be expressed in each subpixel included in the pixel by using the selected color signal value and corresponding color signal values of the peripheral pixel; And (d) driving the display to control the brightness of the image to be expressed in the image display device according to the calculated subpixel brightness value.

In addition, in order to achieve the above-described technical problem, an image display apparatus including subpixels respectively displaying four or more different colors, and including pixels including three different subpixels among the subpixels. Another method for expressing may include: (a) selecting one of the remaining color signals other than the predetermined two color signals among four or more color signals according to the type of subpixel included in the pixel; (b) obtaining selected color signal values to be represented in the peripheral pixels of the pixel; (c) calculating a brightness value to be expressed in the subpixel using the selected color signal value and corresponding color signal values of the peripheral pixels; And (d) driving the display to control the brightness of the image to be expressed in the image display device according to the calculated three subpixel brightness values.

In addition, step (c) of the above-described image representation method may include a predetermined output to express a color signal of a subpixel included in a pixel among input color signals in a region corresponding to each subregion of the (c1) region mask. Generating a representative value, which is a color signal value of, for each mask subregion; (c2) generating deviation information between the representative value between the central subregion and the adjacent subregion of the mask; And (c3) generating an output color signal value to be expressed by a subpixel included in the center subregion of the mask in order to express a predetermined color signal among the input color signals in the entire mask region according to the representative value and the deviation information. Wherein the mask has a predetermined number of subregions smaller than the size of the pixel, and the central subregion of the mask is set to include subpixels representing a predetermined color signal.

On the other hand, the image display device of the present invention for achieving the above-described technical problem, includes a subpixel for displaying each of at least four different colors, and includes a pixel consisting of three different subpixels of the subpixels An image display apparatus, comprising: a signal selector for selecting three color signals for each pixel according to a type of a subpixel among four or more color signals; A color signal value extraction unit for obtaining selected color signal values to be expressed in the peripheral pixels of each pixel; A subpixel representation unit configured to calculate a brightness value to be expressed in a subpixel included in each pixel by using the selected color signal value and corresponding color signal values of neighboring pixels; And a display driver for controlling brightness of an image to be expressed in the image display device according to the calculated subpixel brightness value.

In addition, another image expression method of the present invention for achieving the above-described technical problem, includes a sub-pixel displaying each of four or more different colors, and includes a pixel consisting of three different sub-pixels of the sub-pixels An image display apparatus comprising: a signal selector configured to select one of the remaining color signals other than two predetermined color signals among four or more color signals according to a type of a subpixel included in a pixel; A color signal value extraction unit for obtaining selected color signal values to be expressed in the peripheral pixels of the pixel; A subpixel representation unit configured to calculate a brightness value to be expressed in the subpixel using the selected color signal value and corresponding color signal values of neighboring pixels; And a display driver for controlling brightness of an image to be expressed in the image display device according to the calculated three subpixel brightness values.

In addition, the sub-pixel expression unit of the image representation apparatus is a predetermined color signal value to be output to express the color signal of the sub-pixel included in the pixel among the input color signals in the region corresponding to each sub-region of the area mask. A representative value calculator for generating a representative value for each mask subregion; A difference value calculator for generating deviation information between the representative subregions of the mask and the representative subregions; And generating a subpixel value for generating an output color signal value to be expressed by a subpixel included in the center subregion of the mask in order to express a predetermined color signal among the input color signals in the entire mask region according to the representative value and the deviation information. Preferably, the mask has a predetermined number of subregions smaller than the size of the pixel, and the center subregion of the mask is set to include a subpixel representing a predetermined color signal.

On the other hand, another image expression method of the present invention for achieving the above-described technical problem is a method of representing an image in the image display device having a plurality of pixels including a plurality of sub-pixels, (a) smaller than the size of the pixel Setting a mask such that a central subregion of the mask having a predetermined number of subregions includes a subpixel representing a predetermined color signal; (b) generating, for each mask subregion, a representative value, which is a color signal value to be output in order to express the predetermined color signal among input color signals in a region corresponding to each subregion of a mask; (c) generating deviation information between the representative value between a central subregion of the mask and an adjacent subregion; And (d) generating an output color signal value to be expressed by a subpixel included in the center subregion of the mask in order to express the predetermined color signal among the input color signals in the entire mask region according to the representative value and the deviation information. Steps.

In addition, another method for representing an image in the image display apparatus having a plurality of pixels including a plurality of subpixels for achieving the above technical problem, (a) out of the first predetermined number of color signals to be expressed in the image representation device Selecting a second predetermined number of color signals in accordance with the type of encoding station of the video representation apparatus; (b) setting a mask such that the central subregion of the mask having a predetermined number of subregions smaller than the size of the pixel includes a subpixel representing a predetermined color signal of the second predetermined number of color signals; (c) generating, for each mask subregion, a representative value which is a color signal value to be output in order to express a predetermined color signal among the second predetermined number of color signals in a region corresponding to each subregion of the mask; (d) generating deviation information between the representative value between the central subregion and the adjacent subregion of the mask; (e) generating an output color signal value to be expressed by a subpixel included in the central subregion of the mask in order to express a predetermined color signal among the second predetermined number of color signals in the entire mask region according to the representative value and the deviation information; ; And (f) performing steps (b) to (e) for every second predetermined number of color signals.

On the other hand, in order to achieve the above technical problem, an image expression apparatus including a plurality of pixels including a plurality of subpixels of the present invention may be configured by using a mask having a predetermined number of subregions smaller than the size of a pixel. A representative value generator for generating a representative value for each of the mask subregions, which is a color signal value to be output in order to express a predetermined color signal in a region corresponding to each subregion; A deviation information generation unit for generating deviation information between a representative value between a central subregion of the mask and an adjacent subregion; And a subpixel value generator configured to generate an output color signal value to be expressed by a subpixel included in the center subregion of the mask in order to express a predetermined color signal among the input color signals in the entire mask region according to the representative value and the deviation information. And a display driver for controlling an image signal to be expressed according to the output color signal value generated by the subpixel value generator.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

Hereinafter, a method and an apparatus for displaying an image in an image display apparatus including three subpixels among subpixels in which each pixel represents four colors will be described. However, it will be apparent to those skilled in the art that the image expression method of the present invention can be applied to an image display device in which each pixel includes three or more subpixels among subpixels representing four or more colors.

1 is a diagram illustrating an example of an RGB stripe type filter structure in a video display device.

The four-channel image display methods of adding white or arbitrary primary colors to the RGB three channels as shown in FIG. 1 have an advantage of increasing the output light amount when the additional primary colors are white, and the primary colors added are other than RGB primary colors. In this case, there is an advantage in that the color gamut can be increased.

In addition, there have been many studies on converting signals from RGB 3 channels to RGBW 4 channels in which another color W is added while preventing disadvantages such as color shift when adding an arbitrary primary color. There is a method of generating a 4-channel signal of RGBW by extracting a W signal from RGB and updating the corresponding RGB signal using the extracted W signal.

2A and 2B illustrate a color filter structure in which another primary color W is added to RGB in an LCD image display device. Here, W means any color that is not White or RGB.

In the case of the color filter shown in Fig. 2A, the W filter cells exist one in one device pixel indicated by a dotted line, where one device pixel has a total of four sub-pixels in the form of a 2x2 grid. In the case of the color filter shown in FIG. 2B, the W filter cells exist one in one device pixel indicated by a dotted line, where one device pixel has a total of four sub-pixels of stripe type.

In the case of the color filter shown in Figs. 3A and 3B, each of the W and B filter cells alternately exist one per two device pixels, with one device pixel having a total of three subpixels. In the filter of FIG. 3A, pixels of each row and each column are alternately arranged in the order of RGB-RGW. In the filter of FIG. 3B, pixels are arranged in RBG-RWG order for odd rows, pixels are arranged in GWR-GBR order for odd rows, pixels are arranged in RBG-GWR order for odd columns, and RWG-GBR orders for even columns. The pixels are arranged.

As shown in FIGS. 2A to 3B, the color filter structure of the RGBW 4-channel image display device may have a complex and diverse structure different from that of the RGB 3-channel filter, depending on an input resolution different from the device resolution. Each device subpixel RGBW star color scheme should be performed.

4A is a block diagram illustrating a configuration of an image representation apparatus according to an exemplary embodiment of the present invention, and FIG. 5A is a flowchart illustrating a method of representing an image in the image representation apparatus according to the preferred embodiment of the present invention.

The image presenting apparatus of the present invention includes a signal converter 410, a signal presenter 420, and a display driver 470.

The three color image signals R, G, and B are input to the signal converter 410 (S200), and the signal converter 410 receives the three color signals and converts the signals into four color signals, and converts the converted four color signals. The signal is output to the signal expression unit 420 (S220).

The signal expression unit 420 receives a four-color signal, calculates brightness values of device subpixels for three signals among the four input signals, and outputs the result to the display driver 470 (S240). The display driver 470 controls the output brightness according to the brightness value of the input three-color signal (S260).

When a video signal having an arbitrary spatial resolution larger than the spatial resolution of the display device is input to the four-color (RGBW) image representation device having a predetermined spatial resolution, the input video signal is converted into a signal. The four-color signal is generated in the unit 410, and the four-color signal is input to the signal expression unit 420.

Hereinafter, the configuration and signal processing of the signal representation unit 420 will be described with reference to FIGS. 4B and 5B. 4B and 5B are four primary color image display apparatuses as in the case of FIG. 3A or 3B, but show the configuration and processing of the signal expression unit 420 applicable to the case where each device pixel is composed of three subpixels. do.

4B is a block diagram showing the configuration of the signal representation unit 420, and FIG. 5B is a flowchart for explaining a signal representation method.

The signal representation 420 illustrated in FIG. 4B includes a first subpixel representation 430, a second subpixel representation 440, a third subpixel representation 450, and a signal selector 460. do.

Two signals of the four color signals output from the signal converter 410 are input to the first subpixel representation 430 and the second subpixel representation 440, respectively, and the first subpixel representation 430 is provided. The second subpixel representation unit 440 recalculates the level values for representing the first subpixel and the second encoder according to the difference in the arrangement of the spatial positions between the device subpixels (S242 and S244).

The other two signals of the four color signals output from the signal converter 410 are input to the signal selector 460, and the signal selector 460 is input according to the device subpixel filter type at the image position to be expressed. One of the two selected signals is selected and output (S246).

The signal output from the signal selector 460 is input to the third subpixel representation 450, and the third subpixel representation 450 according to the arrangement difference of the spatial position between the device subpixels. Recalculate the level value to represent (S248). The two signals input to the signal selector 460 are signals corresponding to subpixels alternated with each device pixel.

FIG. 4C is a block diagram illustrating the configuration of the first subpixel representation unit 430, and the second subpixel representation unit 440 and the third subpixel representation unit 450 are also the first encoder representation unit 430. Has the same configuration as The first subpixel representation unit 430 includes a representative value calculator 431, a difference value calculator 433, an increase / decrease amount calculator 435, and a level value calculator 437.

5C is a flowchart illustrating a process of recalculating an image signal level for subpixel representation in the first subpixel representation unit 430.

The image signal P1 input to the first subpixel representation unit 430 is input to the representative value calculator 431, and the representative value calculator 431 calculates a representative value for each mask subregion (S510).

The mask used in the present invention is used to calculate a brightness value to be expressed by each subpixel of the image display apparatus, and is composed of cells having a size corresponding to the size of each subpixel and having a predetermined number of areas. The mask used in the present invention may have a 3 × 3 spatial region as shown in FIG. 6A, or may have a 5 × 5 spatial region as shown in FIG. 6B. Other sizes are possible, and of course, the horizontal and vertical sizes may not be the same.

Determination of the size of the mask subregion and the weight of each mask subregion of the present invention depends on the type of the device subpixel constituting the device pixel. FIG. 7 illustrates a form of a color filter that can be applied to the present invention. The filter structure shown in FIG. 7 is a filter structure of the RGBW four-channel image display device shown in FIG. The spatial resolution (horizontal 8, vertical 5) is larger than the 4 x 4 spatial resolution (horizontal 4, vertical 4) of the image display device.

In this case, since the device pixels alternate the structures of RGB and RGW, each of the R and G device subpixels has 16, but only 8 B and W device subpixels are provided.

Therefore, the mask area size (see 61 and 62 of FIG. 9A) for the device subpixel processing for the R and G components and the mask area size (see 63 and 64 of FIG. 9B) for the B and W device subpixel processing should be different. .

However, as shown in FIG. 8, when all the device subpixels constituting the device pixel are the same, the mask area size may be the same for all of the RGBW as shown in FIG. 10. In a preferred embodiment of the present invention, the input image resolution is set to 1280 (W) x 768 (H), the device resolution is 640 (W) x 768 (H), and the mask size is set to 3 x 3, respectively. The size is the same as the device sub-pixel size, and the weight for each mask area is set to m22 = 1/2, m12 = m21 = m23 = m32 = 1/8, m11 = m33 = m31 = m33 = 0.

The representative value calculator 431 calculates representative values for each mask subregion, and calculates values of nine mask subregions for a 3 × 3 mask and calculates 25 mask subregions for a 5 × 5 mask. .

Referring to FIG. 5D, which is a flowchart illustrating a process of the representative value calculator 431, as illustrated in FIGS. 9A and 9B, one or more image pixels overlapping an arbitrary subpixel area may be provided. The representative value calculator 431 multiplies the brightness value of the image pixel placed in the mask subregion by the weight of the area occupied by the image pixel (S512).

The representative value calculator 431 calculates values Mref () (hereinafter, referred to as mask subregion representative values) representing these mask subregions for each mask subregion according to Equation 1 below (S514).

Here, i is an index indicating the i th subregion of the mask subregions, q is the number of image pixels in the i th mask subregion, and A (i, j) is j in the i th mask subregion. I (i, j) is the brightness value of the j th image pixel in the i th mask subregion.

Meanwhile, in the embodiment of the present invention, the weight A (i, j) is obtained as the area ratio of the j th image pixel in the i th mask subregion. The area ratio is different depending on the ratio of the image resolution and the device resolution, and the arrangement of the device subpixels.

The representative value calculation for each mask subregion is performed by the set number of mask sizes (S520). In the embodiment of the present invention, only the central mask subregion m22 and the upper, lower, left, and right neighboring mask subregions m21, m12, m23, and m32 are used in a 3x3 mask size.

The video signal whose representative value of the mask subregion is calculated is input to the difference value calculator 433, and the difference value calculator 433 obtains the difference value by obtaining spatial deviation information of adjacent mask subregions in each mask subregion. Calculate (S520).

Referring to FIG. 5E, which is a detailed flowchart of the step S520 of FIG. 5C, the difference value calculator 433 first determines that the mask subregion to which the difference value is to be calculated is the center (when the size of the mask is 3 × 3, m22, mask). If the size is 5 x 5, it is checked whether m33) (S521).

If the subregion to which the difference value is to be calculated is the center, Neighbor_ave (i), which is an average value of the representative values of the peripheral mask subregions, is obtained (S522). Thereafter, the difference between the average value and Mref (i), which is a representative value of the center mask subregion, is calculated (S523), and Mdiff (i), which is a difference value for each mask subregion, is extracted (S525).

If the mask subregion is not the center, the difference calculator 433 calculates a difference between the representative value of the central mask subregion and the representative mask subregion representative value as shown in Equation 2 (S524). In operation S525, Mdiff (i), which is a difference value of each mask subregion, is extracted.

The difference value calculation unit 433 checks whether the difference values of all the subregions have been calculated, and repeats the above-described process until the difference values of all the mask subregions are calculated (S526). If it is calculated, the calculated result is output to the increase / decrease calculator 435.

The increase / decrease calculator 435 that receives the image signal controls the magnitude of the increase / decrease amount to be applied to the device subpixel using the spatial deviation information calculated in step S520 described above (S530).

Referring to FIG. 5F, which is a detailed flowchart of step S530 of FIG. 5C, the increase / decrease amount calculation unit 435, for each of the input mask subregions, represents a representative value Mref (i) of the mask subregion and a difference value of the mask subregion. Multiply Mdiff (i) (S532). Thereafter, the increase / decrease calculator 435 extracts the increase / decrease amount Minc (i) for each mask subregion by multiplying the multiplied value by a predetermined weight W2 (i) as shown in Equation 3 below (S534).

The increase / decrease calculation unit 435 checks whether the increase / decrease amount is calculated for all the mask subregions (S536), and repeats steps S532 and S534 for all the subregions. The increase / decrease amounts calculated for all the mask subregions are output to the level value calculator 437.

The device subpixel value calculator 437 calculates the device subpixel value using the increase / decrease amount calculated for each mask subregion (S540).

Referring to FIG. 5G, the level value calculator 437 receiving an image signal sets the device subpixel value to 0 (S541), and then represents a representative value of each mask subregion Mref (i) and a corresponding mask subregion. The increase and decrease Minc (i) is added (S542).

Thereafter, the level value calculator 437 multiplies the added value by the weight W3 (i) of the mask subregion (S543), and accumulates the resultant value on the device subpixel value (S544).

When the level value calculator 437 performs the above-described operations S542 to S544 for all sub-regions (S545), the device sub-pixel value Sout (x, y) at the corresponding position is extracted as shown in Equation 4 below. (S546).

FIG. 11A is a block diagram illustrating a configuration of an image representation apparatus according to an exemplary embodiment of the present invention, which may be applied when the number of subpixels constituting one device pixel illustrated in FIGS. 2A and 2B is four. 2A and 2B are flowcharts illustrating a method of representing an image in an image rendering apparatus according to another exemplary embodiment of the present invention, which may be applied when the number of subpixels constituting one device pixel is four.

The image presenting apparatus of the present invention, which is applicable when the number of subpixels constituting one device pixel is 4, includes a signal converter 1110, a second signal presenter 1120, and a second display driver 1170. In addition, the second signal representation unit 1120 may include a fourth subpixel representation 1130, a fifth subpixel representation 1140, a sixth subpixel representation 1150, and a seventh subpixel representation 1160. It includes.

When an image signal of RGB three colors having an arbitrary spatial resolution larger than the spatial resolution of the display device is input to the four-color (RGBW) image representation device having the predetermined spatial resolution (S1200), The three-color image signals R, G, and B are converted into four-color signals by the signal converter 1110, and the converted four-color signals are output to the second signal expression unit 1120 (S1220).

The second signal expression unit 1120 receives the four-color signal and calculates brightness values for each device subpixel for all four input signals and outputs the result to the second display driver 1170 (S1240). .

Each of the four color signals output from the signal converter 1110 may include a fourth subpixel representation 1130, a fifth subpixel representation 1140, a sixth subpixel representation 1150, and a seventh subpixel representation. In operation 1160, the level value is recalculated according to an arrangement difference between the spatial positions of the device subpixels. Detailed block diagrams of the fourth subpixel expression unit 1130, the fifth subpixel expression unit 1140, the sixth subpixel expression unit 1150, and the seventh subpixel expression unit 1160 illustrated in FIG. 11B are shown. It is the same as the first subpixel representation unit 430, and the subpixel representation methods are also applicable to the encoding representation method shown in FIG. 5C.

The second display driver 1170 controls the output brightness according to the brightness value of the input four-color signal (S1260).

The invention can also be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, which are also implemented in the form of a carrier wave (for example, transmission over the Internet). It also includes. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

So far I looked at the center of the preferred embodiment for the present invention. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

According to the image representation method and apparatus of the present invention, the resolution of the low resolution representation of the image representation apparatus is improved by controlling the subpixels, thereby reducing the aliasing phenomenon causing the image quality degradation when the high resolution image is represented on the low resolution image display apparatus. You can. Due to such a configuration, it is possible to obtain an effect of reducing a driver driver chip, removing a fine process work, and increasing an amount of filter transmitted light, as compared with a method of increasing the physical spatial resolution of an image display device.

In particular, in a preferred embodiment of the present invention in which an image is expressed in four channels by adding one primary color to an input signal representing three primary colors of RGB, the four-channel image display method may increase the output light amount when the additional primary color is white. In addition, when the additional primary color is a primary color other than RGB, an effect of increasing the color gamut that can be expressed can be additionally obtained.

1 is a diagram illustrating an example of an RGB stripe type filter structure in a video display device.

2A and 2B illustrate an example of a color filter structure in which another primary color W is added to RGB in an LCD image display device.

3A and 3B illustrate another example of a color filter structure in which another primary color W is added to RGB in an LCD image display device.

4A is a block diagram illustrating a configuration of an image expression apparatus according to an exemplary embodiment of the present invention.

FIG. 4B is a block diagram showing the configuration of the signal expression unit 420 shown in FIG. 4A.

FIG. 4C is a block diagram showing the configuration of the subpixel representation unit 430 shown in FIG. 4B.

FIG. 5A is a flowchart illustrating a process of the image signal representation apparatus illustrated in FIG. 4A.

FIG. 5B is a detailed flowchart of step S240 shown in FIG. 5A.

FIG. 5C is a detailed flowchart of step S510 shown in FIG. 5B.

5E to 5G are detailed flowcharts illustrating the processing of each step shown in FIG. 5C.

6A and 6B are diagrams illustrating a mask size according to a preferred embodiment of the present invention.

7 and 8 are diagrams illustrating a case where the resolution of the input image and the resolution of the image display apparatus are different.

9A and 9B illustrate an example of applying a mask to the pixel blocks illustrated in FIG. 7.

FIG. 10 is a diagram illustrating an example of applying a mask to the pixel blocks illustrated in FIG. 8.

11A is a block diagram illustrating a configuration of an image expression apparatus according to another exemplary embodiment of the present invention.

FIG. 11B is a block diagram showing the configuration of the second signal expression section shown in FIG. 11A.

FIG. 12 is a flowchart for describing a processing process of the apparatus for representing video signals shown in FIG. 11A.

Claims (41)

A method of expressing an image in an image display device including subpixels displaying four or more different colors, and including pixels consisting of three different subpixels among the subpixels. (a) selecting three color signals according to types of subpixels constituting a predetermined pixel among the four or more color signals; (b) obtaining the selected color signal values of peripheral pixels of the pixel; (c) calculating a brightness value to be expressed in each subpixel included in the pixel by using the selected color signal value and corresponding color signal values of the peripheral pixel; And and (d) driving the display to control the brightness of the image to be expressed in the image display device according to the calculated subpixel brightness value. The method of claim 1, wherein before step (a), And a signal conversion step of receiving a three-color video signal and converting the video signal into four or more color video signals. delete The method of claim 1, wherein (a) to (d) And image display is performed on all pixels of the image display device. A method of expressing an image in an image display device including subpixels displaying four or more different colors, and including pixels consisting of three different subpixels among the subpixels. (a) selecting one of the remaining color signals other than the predetermined two color signals among the four or more color signals according to the type of subpixel included in the pixel; (b) obtaining the selected color signal values to be represented in peripheral pixels of the pixel; (c) calculating a brightness value to be expressed in the subpixel using the selected color signal value and corresponding color signal values of the peripheral pixels; And and a display driving step of controlling brightness of an image to be expressed in the image display device according to the calculated three subpixel brightness values. The method of claim 5, wherein before step (a), And a signal conversion step of receiving a three-color video signal and converting the video signal into four or more color video signals. delete The method of claim 1 or 5, wherein step (c) (c1) A representative value, which is a predetermined color signal value to be output to represent a color signal of a subpixel included in the pixel among the input color signals in a region corresponding to each subregion of an area mask, is assigned to each mask subregion. Generating an image; (c2) generating deviation information between the representative value between the central subregion and the adjacent subregion of the mask; And (c3) an output color signal value to be expressed by a subpixel included in the center subregion of the mask in order to express the predetermined color signal among the input color signals in the entire mask region according to the representative value and the deviation information; Generating a; And the mask has a predetermined number of subregions smaller than the size of a pixel, and the central subregion of the mask is set to include a subpixel representing the predetermined color signal. The method of claim 8, wherein step (c1) And generating the representative value by multiplying an area weight by an input color signal value to be expressed in the mask subregion. The method of claim 8, wherein step (c2) And generating deviation information of the mask subregion adjacent to the mask center subregion by calculating a difference between the representative value of the mask subregion and a mask subregion adjacent to the mask center subregion. . The method of claim 8, wherein step (c3) The increase / decrease amount of the representative value of each mask subregion is calculated according to the representative value and the deviation information for each mask subregion, and the representative value is added to the increase / decrease amount to represent the subpixel included in the central subregion of the mask. And an output color signal value. A recording medium which can read the image representation method according to any one of claims 1 to 7, and which is recorded by executable program code. A recording medium which can read the image representation method of claim 8 in a computer-readable program and executable program code. An image display device including sub-pixels each displaying four or more different colors, and including pixels including three different sub-pixels among the sub-pixels. A signal selector which selects three color signals for each pixel according to the type of subpixel among the four or more color signals; A color signal value extraction unit for obtaining the selected color signal values to be expressed in peripheral pixels of each pixel; A subpixel representation unit configured to calculate a brightness value to be expressed in a subpixel included in each pixel by using the selected color signal value and corresponding color signal values of the peripheral pixels; And And a display driver configured to control the brightness of an image to be expressed in the image display device according to the calculated subpixel brightness value. The method of claim 14, And a signal converter which receives a three-color video signal and converts the video signal into four or more color video signals and outputs the same to the signal selector. delete An image display device including sub-pixels each displaying four or more different colors, and including pixels including three different sub-pixels among the sub-pixels. A signal selector configured to select one of the remaining color signals other than the predetermined two color signals among the four or more color signals according to the type of subpixel included in the pixel; A color signal value extraction unit for obtaining the selected color signal values to be expressed in peripheral pixels of the pixel; A subpixel representation unit configured to calculate a brightness value to be expressed in the subpixel using the selected color signal value and corresponding color signal values of the peripheral pixels; And And a display driver for controlling brightness of an image to be expressed in the image display device according to the calculated three subpixel brightness values. The method of claim 17, And a signal converter which receives a three-color video signal and converts the video signal into four or more colors and outputs the signal to the signal selector. delete 18. The method of claim 14 or 17, wherein the subpixel representation is A representative value, which is a predetermined color signal value to be output in order to express a color signal of a subpixel included in the pixel among the input color signals in a region corresponding to each subregion of an area mask, is generated for each mask subregion. Representative value calculator; A difference value calculator which generates deviation information between the representative value between the center subregion and the adjacent subregion of the mask; And According to the representative value and the deviation information, to generate an output color signal value to be expressed by the sub-pixel included in the center sub-region of the mask in order to express the predetermined color signal among the input color signals in the entire mask area Sub-pixel value generation unit, And the mask has a predetermined number of subregions smaller than the size of a pixel, and the center subregion of the mask is set to include subpixels representing the predetermined color signal. The method of claim 20, wherein the representative value calculation unit And generating the representative value by multiplying an area weight with an input color signal value to be expressed in the mask subregion. The method of claim 20, wherein the difference value calculator And calculating the difference between the representative value of the mask center subregion and the representative value of the mask subregion adjacent to the mask center subregion to generate deviation information of the mask subregion adjacent to the mask center subregion. 21. The method of claim 20, wherein the subpixel value generator The increase / decrease amount of the representative value of each mask subregion is calculated according to the representative value and the deviation information for each mask subregion, and the representative value is added to the increase / decrease amount to represent the subpixel included in the central subregion of the mask. And an output color signal value. A method of expressing an image in an image display device having a plurality of pixels including a plurality of subpixels, (a) setting a mask such that a central subregion of the mask having a predetermined number of subregions smaller than the size of the pixel includes a subpixel representing a predetermined color signal; (b) generating, for each mask subregion, a representative value which is a color signal value to be output in order to express the predetermined color signal among input color signals in a region corresponding to each subregion of the mask; (c) generating deviation information between the representative value between the central subregion and the adjacent subregion of the mask; And (d) generating an output color signal value to be expressed by a subpixel included in the center subregion of the mask in order to express the predetermined color signal among the input color signals in the entire mask region according to the representative value and the deviation information; An image representation method comprising the step. The method of claim 24, wherein step (b) And generating the representative value by multiplying an area weight with an input color signal value to be expressed in the mask subregion. The method of claim 24, wherein step (c) And calculating the difference between the average value of the representative values of the adjacent mask subregions and the representative value of the central mask subregion to generate the deviation information of the central subregion. The method of claim 24, wherein step (c) And calculating the difference between the representative value of the mask center subregion and the representative value of the mask subregion adjacent to the mask center subregion to generate deviation information of the mask subregion adjacent to the mask center subregion. The method of claim 24, wherein step (d) The increase / decrease amount of the representative value of each mask subregion is calculated according to the representative value and the deviation information for each mask subregion, and the representative value is added to the increase / decrease amount to represent the subpixel included in the central subregion of the mask. And an output color signal value. A method of expressing an image in an image display device having a plurality of pixels including a plurality of subpixels, (a) selecting a second predetermined number of color signals from among the first predetermined number of color signals to be expressed in the image representation device according to the type of sub-pixel of the image representation device; (b) setting a mask such that a central subregion of the mask having a predetermined number of subregions smaller than the size of the pixel includes a subpixel representing a predetermined color signal of the second predetermined number of color signals; (c) generating, for each mask subregion, a representative value which is a color signal value to be output to express the predetermined color signal among second predetermined number of color signals in a region corresponding to each subregion of the mask; (d) generating deviation information between the representative value between the central subregion and the adjacent subregion of the mask; (e) an output color signal to be expressed by a subpixel included in the central subregion of the mask in order to express the predetermined color signal among the second predetermined number of color signals in the entire mask area according to the representative value and the deviation information; Generating a value; And and (f) performing steps (b) to (e) for every second predetermined number of color signals. The method of claim 29, wherein prior to step (a) And receiving a three-color image signal and converting the three-color image signal into the first predetermined number of image signals. The method of claim 29, wherein step (c) And generating the representative value by multiplying an area weight with an input color signal value to be expressed in the mask subregion. The method of claim 29, wherein step (d) And generating deviation information of the central subregion by calculating a difference between an average value of representative values of an adjacent mask subregion and a representative value of the central mask subregion. The method of claim 29, wherein step (d) And calculating the difference between the representative value of the center mask region and the representative value of the mask subregion adjacent to the center mask subregion to generate deviation information of the mask subregion adjacent to the center mask subregion. The method of claim 29, wherein step (e) The increase / decrease amount of the representative value of each mask subregion is calculated according to the representative value and the deviation information for each mask subregion, and the representative value is added to the increase / decrease amount to represent the subpixel included in the central subregion of the mask. And an output color signal value. An image representation device having a plurality of pixels including a plurality of subpixels, Each mask unit uses a mask having a predetermined number of sub-regions smaller than the size of the pixel to represent a representative value, which is a color signal value to be output in order to express a predetermined color signal in a region corresponding to each sub-region of the mask. A representative value generator for generating a region; A deviation information generation unit generating deviation information between the representative value between the center subregion and the adjacent subregion of the mask; And Subpixel value generation for generating an output color signal value to be expressed by a subpixel included in the central subregion of the mask in order to express the predetermined color signal among input color signals in the entire mask region according to the representative value and the deviation information. part; And And a display driver for controlling an image signal to be expressed according to the output color signal value generated by the subpixel value generator. The method of claim 35, wherein the representative value generating unit And representing the representative value by multiplying an area weight with an input color signal value to be output from the mask subregion. 36. The apparatus of claim 35, wherein the deviation information generator And calculating the difference between the average value of the representative values of the adjacent mask subregions and the representative value of the central mask subregion to generate the deviation information of the central subregion. 36. The apparatus of claim 35, wherein the deviation information generator And calculating deviation information of a mask subregion adjacent to the center mask subregion by calculating a difference between a representative value of the center mask subregion and a mask subregion adjacent to the center mask subregion. 36. The method of claim 35, wherein the subpixel value generator The increase / decrease amount of the representative value of each mask subregion is calculated according to the representative value and the deviation information for each mask subregion, and the representative value is added to the increase / decrease amount to represent the subpixel included in the central subregion of the mask. And an output color signal value. 36. The method of claim 35 wherein And a signal selector configured to select a second predetermined number of color signals from among the first predetermined number of color signals inputted according to the type of subpixel to express the image and output the second predetermined number of color signals to the representative value generator. The method of claim 40, And a signal converter which receives a three-color image signal and converts the three-color image signal into the first predetermined number of image signals.