Apparatus and method for compressing coefficient values of an equation and circuit for compensating display data using compressed values

Abstract

The present disclosure discloses an apparatus and method for compressing coefficient values of a compensation equation for compensating for defects in an image and a circuit for compensating for display data using compressed values compressed by the apparatus and method. The apparatus for compressing coefficient values of a compensation equation includes a coefficient value providing unit configured to provide, for each pixel, a coefficient value of a coefficient of a compensation equation for compensating for defects in an image and position information, and a coefficient value compressing unit configured to provide a first compressed bitmap and a second compressed bitmap by sequentially performing a first compression and a second compression on the coefficient value.

Description

Technical Field

[0001] This disclosure relates to the compression of coefficient values ​​of a compensation equation for compensating defects in an image, and more specifically, to an apparatus and method for compressing coefficient values ​​of a compensation equation for compensating defects in an image, and to circuitry for using the compressed values ​​compressed by the apparatus and method to compensate display data. Background Technology

[0002] Recently, LCD panels or OLED panels have been widely used as display panels.

[0003] During the manufacturing process, due to factors such as errors, the display panel may have defects such as color difference (mura) in the image.

[0004] For example, color difference fault means that there are spots of light with uneven brightness in a specific pixel or area of ​​the display panel.

[0005] Defects in an image can increase with the size of the display panel and are used as an important factor in determining the quality of the display panel.

[0006] Therefore, in order to improve the quality of display panels, it is necessary to effectively compensate for defects.

[0007] Defects in an image can be improved by compensating for the brightness of the display data for each pixel. To this end, the driver of the display panel can be configured to include a defect compensation unit for compensating for defects in the image based on previously stored compensation information.

[0008] The defect compensation unit can compensate for the brightness of the received display data for each pixel based on compensation information. The driver can then drive the display panel using the compensated display data.

[0009] The defect compensation unit can be configured to perform defect compensation by using a preset compensation equation. For example, the compensation equation can be configured as a quadratic expression.

[0010] The degree of brightness compensation for each pixel can be determined by the coefficient values ​​of the compensation equation. Therefore, the compensation information stored in the driver can include the coefficient values ​​for each pixel, which will be applied to the compensation equation.

[0011] As display panel sizes increase, the amount of compensation information needed to compensate for defects in all images also increases. This increase in compensation information necessitates higher-capacity memory. Therefore, to reduce memory capacity, the compensation information needs to be compressed.

[0012] If compensation information is compressed at a high compression ratio and a large region is selected for compression, artifacts may appear between the compressed regions.

[0013] To prevent such artifacts, the compensation information needs to be compressed effectively in a way that creates correlation between adjacent pixels or blocks. Summary of the Invention

[0014] Various implementations are intended to provide apparatus and methods for compressing coefficient values ​​of compensation equations used to compensate for defects in an image, which can reduce memory capacity by effectively compressing the coefficient values ​​of compensation equations used to compensate for defects in an image for each pixel.

[0015] Furthermore, various embodiments are intended to provide an apparatus and method for compressing the coefficient values ​​of a compensation equation used to compensate for defects in an image, which can prevent artifacts from appearing between compressed regions and effectively compress the coefficient values ​​of the compensation equation for each pixel in a manner that is correlated between adjacent pixels or blocks.

[0016] Furthermore, various embodiments are intended to provide circuitry for compensating display data, which can address defects in an image by compensating for the brightness of each pixel based on a compressed value that has been effectively compressed as described above.

[0017] In an embodiment, the apparatus for compressing the coefficient values ​​of a compensation equation for compensating defects in an image may include: a coefficient value providing unit configured to provide coefficient values ​​and position information of the coefficients of the compensation equation for compensating defects in an image for each pixel; and a coefficient value compression unit configured to provide a first compressed bitmap and a second compressed bitmap by sequentially performing a first compression and a second compression on the coefficient values.

[0018] In this configuration, through the first compression, the coefficient value compression unit can construct a first two-dimensional (2-D) table for the coefficient values ​​based on location information, generate a first compressed bitmap having a first compressed value obtained by compressing the coefficient values ​​of the first 2-D table, and generate a representative value for recovering the first compressed value. Furthermore, through the second compression, the coefficient value compression unit can construct a second 2-D table for the representative value based on location information, and generate a second compressed bitmap having a second compressed value obtained by compressing the representative value of the second 2-D table.

[0019] In an implementation, a method for compressing the coefficient values ​​of a compensation equation used to compensate for defects in an image may include: a first step of receiving, for each pixel, the coefficient values ​​of the compensation equation as a first one-dimensional (1-D) table and position information, constructing the compensation equation as a quadratic expression and using it to compensate for defects in the image; and a second step of dividing the image into multiple block regions, sequentially performing a first compression and a second compression on each block region, and providing a first compressed bitmap and a second compressed bitmap.

[0020] In this case, the first compression may include: constructing a first 2D table based on the coefficient values ​​of a first 1-D table using location information; calculating the total average of the coefficient values ​​of the first 2-D table and generating a first compressed bitmap by mapping the first compressed value to a preset value corresponding to a value greater than or less than the total average of each of the coefficient values; generating a first representative value and a second representative value for recovering the first compressed value of the first compressed bitmap, and providing a second 1-D table that commonly includes location information and has the first representative value and the second representative value, respectively.

[0021] In addition, the second compression may include: constructing a second 2-D table based on location information, mapping a first representative value and a second representative value of the second 1-D table to each pixel in each of the second 2-D table; and calculating the difference between the current data and the next data in continuous data, and generating a second compressed bitmap by mapping the second compressed value to the next data as the difference.

[0022] In an embodiment, the apparatus for compensating display data may include: a compressed bitmap storage unit configured to store and provide a first compressed bitmap having a first compressed value and a second compressed bitmap having a second compressed value corresponding to a first representative value and a second representative value, respectively; a coefficient value generation unit configured to generate coefficient values ​​for a compensation equation for compensating defects in an image for each pixel based on the first compressed value of the first compressed bitmap and the second compressed value of the second compressed bitmap, and to provide coefficient values ​​for each pixel; and a defect compensation unit configured to receive display data and coefficient values ​​for each pixel, compensate the display data of each pixel by using a compensation equation to which the coefficient values ​​have been applied, and output the compensated display data.

[0023] This disclosure can effectively compress the coefficient value of each pixel, which will be applied to a compensation equation for compensating defects in an image through continuous compression, and can reduce memory capacity.

[0024] Furthermore, this disclosure can prevent artifacts from appearing between compressed regions and effectively compress the coefficient values ​​of the compensation equation for each pixel in a manner that is correlated between adjacent pixels or blocks.

[0025] Furthermore, the advantage of this disclosure is that it can resolve defects in images because the driver that drives the display panel to display the image compensates for the brightness of each pixel based on the effectively compressed value as described above. Attached Figure Description

[0026] Figure 1 This is a block diagram illustrating an apparatus for compressing coefficient values ​​of a compensation equation for compensating defects in an image, according to a preferred embodiment of the present disclosure.

[0027] Figure 2It is shown Figure 1 A block diagram of a preferred embodiment of the coefficient value compression unit in the diagram.

[0028] Figure 3 It is used to describe Figure 2 A diagram showing the operation of rearrangement unit 42 in the diagram.

[0029] Figure 4 This is a diagram used to describe the operation of compression unit 44.

[0030] Figure 5 It is a first compressed bitmap showing the block area that is reconstructed into an image and stored in the compressed bitmap storage unit 50.

[0031] Figure 6 It is used to describe Figure 2 A diagram showing the operation of rearrangement unit 46 in the diagram.

[0032] Figure 7 This is a diagram used to describe the operation of compression unit 48.

[0033] Figure 8 The second compressed bitmap, which shows the block area, is reconstructed into an image and stored in the compressed bitmap storage unit 50.

[0034] Figure 9 This is a block diagram showing the display system.

[0035] Figure 10 This is a block diagram illustrating a circuit for compensating display data according to an embodiment of the present disclosure, the circuit being configured in... Figure 9 In the drive. Detailed Implementation

[0036] Defects, including color differences in the form of light spots, may appear in the image on the display panel due to factors such as errors during the manufacturing process.

[0037] It can be achieved according to the implementation method Figure 1 The device is used to analyze defects. Correction information based on the analysis results can be compressed and then stored.

[0038] Reference Figure 1 The apparatus for compressing the coefficient values ​​of the compensation equation can be shown as including an image receiving unit 10, a defect detection unit 20, a coefficient value providing unit 30, a coefficient value compression unit 40, and a compressed bitmap storage unit 50.

[0039] The image receiving unit 10 is used to receive a precisely detected image of a test image displayed on a display panel (not shown) in order to detect defects and provide the received image.

[0040] The defect detection unit 20 is used to compare the received image with, for example, a previously stored reference image used for testing, to detect defect information for each pixel as a result of the comparison and to provide defect information.

[0041] The coefficient value providing unit 30 receives the defect information of each pixel and generates a coefficient value based on the defect information of each pixel.

[0042] This disclosure may demonstrate the use of a compensation equation configured as a quadratic expression to compensate for defects in an image. In this case, the compensation equation can be understood as Equation 1 below.

[0043] [Equation 1]

[0044] Y = aX 2 +bX+C

[0045] In Equation 1, Y is the brightness value of the pixel to be compensated. X is the normal brightness value of the pixel. That is, Y can be understood as the difference between the defective brightness value and the normal brightness value of the pixel. Furthermore, the coefficients of each dimension of the compensation equation are denoted as "a", "b", and "c".

[0046] The coefficient value providing unit 30 generates coefficients "a", "b", and "c" corresponding to the defect information of each pixel relative to the coefficients of the compensation equation used to compensate for defects in the image, and provides the position information and coefficient value of each pixel. In this case, the coefficient value providing unit 30 can provide the coefficient value and position information of each pixel by constructing the coefficient value and position information in the form of a first one-dimensional (1-D) table.

[0047] The coefficient value compression unit 40 can sequentially perform first compression and second compression on the coefficient values ​​provided by the coefficient value providing unit 30 based on position information, and as a result, can provide a first compressed bitmap and a second compressed bitmap. In this case, the first compressed bitmap based on the first compression can be understood as a bitmap in which the coefficient values ​​have been compressed. The second compressed bitmap can be understood as a bitmap in which the representative values ​​generated by the first compression have been compressed.

[0048] The compressed bitmap storage unit 50 can store a first compressed bitmap and a second compressed bitmap, i.e., the compression result provided by the coefficient value compression unit 40, and can provide the first compressed bitmap and the second compressed bitmap to the driver, which will be described later, according to the manufacturer's intention.

[0049] Embodiments of this disclosure can efficiently compress the coefficient values ​​of each pixel to be applied to the compensation equation into a first compressed bitmap and a second compressed bitmap by sequential compression, and thus can reduce memory capacity.

[0050] Furthermore, embodiments of this disclosure can effectively compress the coefficient values ​​of each pixel in a manner that is correlated between adjacent pixels or blocks by changing one-dimensional (1-D) coefficient values ​​to two-dimensional (2-D) coefficient values, so as to prevent artifacts from appearing between compressed regions.

[0051] Therefore, the coefficient value compression unit 40 can be configured to perform the first compression and the second compression sequentially.

[0052] The coefficient value compression unit 40 first performs a first compression. In the first compression, the coefficient value compression unit 40 configures a first 2-D table for the coefficient values ​​based on the pixel position information, generates a first compressed bitmap having a first compressed value obtained by compressing the coefficient values ​​of the first 2-D table, and generates a representative value for recovering the first compressed value.

[0053] Furthermore, the coefficient value compression unit 40 performs a second compression after the first compression. In the second compression, the coefficient value compression unit 40 configures a second 2-D table for the representative values ​​based on the location information and generates a second compressed bitmap having the second compressed values ​​obtained by compressing the representative values ​​of the second 2-D table.

[0054] The coefficient value compression unit 40 can generate a first compressed bitmap and a second compressed bitmap through sequential first compression and second compression.

[0055] In embodiments of this disclosure, location information can be assigned to each pixel. The coefficient value of each pixel can be matched with the location information.

[0056] Furthermore, embodiments of this disclosure can divide the entire image into multiple block regions for effective compression, and can sequentially perform first compression and second compression on each block region, and can provide a first compressed bitmap and a second compressed bitmap.

[0057] As described above, the first compressed bitmap and the second compressed bitmap obtained for each block region can be stored in the compressed bitmap storage unit 50 and provided in a manner that maps to the entire image.

[0058] The coefficient value compression unit 40 for sequential compression according to embodiments of this disclosure can be as follows: Figure 2 The configuration is as described in [the original text]. You can refer to [the original text]. Figures 3 to 8 describe Figure 2 The operation of the coefficient value compression unit 40 shown.

[0059] The coefficient value compression unit 40 includes a rearrangement unit 42 and a compression unit 44 for first compression, and a rearrangement unit 46 and a compression unit 48 for second compression.

[0060] The rearrangement unit 42 is used to construct a 2-D table (hereinafter referred to as the "first 2-D table") based on the position information for the coefficient values.

[0061] More specifically, the rearrangement unit 42 receives a 1-D table (hereinafter referred to as the "first 1-D table") containing coefficient values ​​and position information for each pixel from the coefficient value providing unit 30. The first 1-D table can be as follows: Figure 3 As shown, it can be arranged to have position information for each pixel and coefficient values ​​for each dimension of the compensation equation, namely “a”, “b”, and “c”.

[0062] The rearrangement unit 42 constructs a first 2-D table for each coefficient of the first 1-D table. For example, it constructs a first 2-D table Ta based on coefficient "a" and maps the coefficient value of coefficient "a" for each piece of location information. That is, it constructs the first 2-D table Ta by mapping the coefficient value of coefficient "a" in the first 1-D table to each pixel based on the location information. Similarly, it constructs a first 2-D table Tb based on coefficient "b" and maps the coefficient value of coefficient "b" for each piece of location information. That is, it constructs the first 2-D table Tb by mapping the coefficient value of coefficient "b" in the first 1-D table to each pixel based on the location information. Furthermore, it constructs a first 2-D table Tc based on coefficient "c" and maps the coefficient value of coefficient "c" for each piece of location information. That is, it constructs the first 2-D table Tc by mapping the coefficient value of coefficient "c" in the first 1-D table to each pixel based on the location information.

[0063] If the image, i.e. the target to be compressed, is configured to include M columns and N rows, then the first 2-D table for each coefficient can be configured to have an M*N matrix structure.

[0064] Compression unit 44 can divide the entire image into multiple block regions and perform a first compression on each block region.

[0065] Reference Figure 4 The diagram shows a first 2-D table Ta based on the coefficient "a", and the first 2-D table Ta is divided into four block regions BA, BB, BC, and BD. In this case, each of the block regions BA, BB, BC, and BD can have an M / 4*N / 4 matrix structure.

[0066] Compression unit 44 can perform compression on each block region of the first 2-D table Ta. As a result, first compressed bitmaps BAC, BBC, BCC, and BDC, corresponding to the four block regions BA, BB, BC, and BD, and two rectangles can be generated, respectively.

[0067] In this context, a moment is a representative value of the first compressed value used to recover the first compressed bitmap for each pixel. A first moment including the first representative value and a second moment including the second representative value can be generated for each block region (hereinafter, the first moment is referred to as the first representative value, and the second moment is referred to as the second representative value).

[0068] That is, a first representative value MA1 and a second representative value MB1 are generated based on the compression of block region BA. A first representative value MA2 and a second representative value MB2 are generated based on the compression of block region BB. A first representative value MA3 and a second representative value MB3 are generated based on the compression of block region BC. A first representative value MA4 and a second representative value MB4 are generated based on the compression of block region BD.

[0069] The first representative values ​​MA1, MA2, MA3, and MA4 can be constructed into a 1-D table (hereinafter referred to as the "second 1-D table") MA. The second representative values ​​MB1, MB2, MB3, and MB4 can be configured into another second 1-D table MB. While having the same block location information, the first representative value and the second representative value corresponding to the same block region are respectively configured in the second 1-D table MA and the second 1-D table MB. In this case, the first representative value and the second representative value can be understood as sharing block location information. In this case, the block location information can be understood as representing the address of the corresponding block region.

[0070] That is, a second 1-D table MA can have four first representative values ​​MA1, MA2, MA3, and MA4 for four block regions BA, BB, BC, and BD, as well as the corresponding block location information. Another second 1-D table MB can have four second representative values ​​MB1, MB2, MB3, and MB4 for four block regions BA, BB, BC, and BD, as well as the corresponding block location information.

[0071] Compression unit 44 calculates the total average of the coefficient values ​​in each of the block regions BA, BB, BC, and BD of the first 2-D table Ta corresponding to coefficient "a", and performs first compression, wherein the first compressed value is mapped to a preset value corresponding to a value that is greater than or less than the total average of the coefficient values ​​in each of the block regions BA, BB, BC, and BD. As a result, compression unit 44 can generate first compressed bitmaps BAC, BBC, BCC, and BDC corresponding to the block regions BA, BB, BC, and BD, respectively.

[0072] Furthermore, compression unit 44 generates first representative values ​​MA1, MA2, MA3, and MA4, and second representative values ​​MB1, MB2, MB3, and MB4, which are used in parallel with the first compression to recover the first compressed bitmaps BAC, BBC, BCC, and BDC for each of the block regions BA, BB, BC, and BD. Additionally, compression unit 44 generates a second 1-D table MA containing multiple block location information and first representative values ​​MA1, MA2, MA3, and MA4 corresponding to the block regions BA, BB, BC, and BD respectively, and a second 1-D table MB containing multiple block location information and second representative values ​​MB1, MB2, MB3, and MB4 corresponding to the block regions BA, BB, BC, and BD respectively.

[0073] That is, compression unit 44 generates a first compressed bitmap BAC to which the first compressed value is mapped, along with a first representative value MA1 and a second representative value MB1, based on block region BA; a first compressed bitmap BBC to which the first compressed value is mapped, along with a first representative value MA2 and a second representative value MB2, based on block region BB; a first compressed bitmap BCC to which the first compressed value is mapped, along with a first representative value MA3 and a second representative value MB3, based on block region BC; and a first compressed bitmap BDC to which the first compressed value is mapped, along with a first representative value MA4 and a second representative value MB4, based on block region BD. Furthermore, the first representative values ​​MA1, MA2, MA3, and MA4 and the second representative values ​​MB1, MB2, MB3, and MB4 for each of the block regions BA, BB, BC, and BD are stored in the second 1-D tables MA and MB, respectively, which share block location information.

[0074] Compression unit 44 can perform first compression by using either Block Truncated Coding (BTC) or Absolute Moment Block Truncated Coding (AMBTC) with a total average value.

[0075] In the case of BTC, in the first 2-D table Ta, the total average can be calculated for each of the four block regions BA, BB, BC, and BD. and standard deviation σ. Total mean The standard deviation σ can be calculated using Equation 2 below.

[0076] [Equation 2]

[0077]

[0078] In Equation 2, m is the number of all pixels in the block region, and x i It is the i-th coefficient value.

[0079] Furthermore, in the first compression, when the coefficient value is greater than the total average value of each pixel in each block region... At that time, by assigning and mapping "1", the first compressed bitmaps BAC, BBC, BCC, and BDC of the corresponding four block regions BA, BB, BC, and BD of the first 2-D table Ta are generated, and when the coefficient value is less than the total average value of each pixel in each block region... At that time, the first compressed bitmaps BAC, BBC, BCC, and BDC are generated by assigning and mapping "0". As a result, the first compressed bitmaps BAC, BBC, BCC, and BDC, which correspond to the four block regions BA, BB, BC, and BD of the first 2-D table Ta, respectively, have "0" or "1" as the first compressed value for each pixel.

[0080] Furthermore, for each of the four block regions BA, BB, BC and BD of the first 2-D table Ta, the first representative value α and the second representative value β can be calculated using the following Equation 3.

[0081] [Equation 3]

[0082]

[0083] In Equation 3, q ​​is a number with a value greater than the overall average.

[0084] That is, the first representative value α is greater than the overall average for each individual. The representative value of the coefficient, and can be understood as each being greater than the overall average. The average standard deviation of the coefficient values ​​is added to the total average. The obtained value. Furthermore, the second representative value β is less than the overall average. The representative value of the coefficient, and can be understood as derived from the total average. Subtract each one that is less than the overall average The value is obtained by taking the average standard deviation of the coefficient values.

[0085] The first representative value α and the second representative value β are used to approximately restore the first compressed value to its original state.

[0086] For each of the four block regions BA, BB, BC, and BD in the first 2-D table Ta, a first representative value α is generated. The second 1-D table MA is configured to include four first representative values ​​α for each of the four block regions BA, BB, BC, and BD, as well as block location information. Furthermore, for each of the four block regions BA, BB, BC, and BD in the first 2-D table Ta, a second representative value β is generated. The second 1-D table MB is configured to include four second representative values ​​β for each of the four block regions BA, BB, BC, and BD, as well as block location information.

[0087] In the case of AMBTC, the total average can be calculated for each of the four block regions BA, BB, BC and BD in the first 2-D table Ta.

[0088] Furthermore, when the coefficient value is greater than the total average value of each pixel in each block region... At that time, by assigning and mapping "1", the first compressed bitmaps BAC, BBC, BCC, and BDC of the corresponding four block regions BA, BB, BC, and BD of the first 2-D table Ta of the first compression are generated, and when the coefficient value of each pixel in each block region is less than the total average value. At that time, the first compressed bitmaps BAC, BBC, BCC, and BDC are generated by assigning and mapping "0". As a result, the first compressed bitmaps BAC, BBC, BCC, and BDC, which correspond to the four block regions BA, BB, BC, and BD of the first 2-D table Ta, respectively, have "0" or "1" as the first compressed value for each pixel.

[0089] Furthermore, for each of the four block regions BA, BB, BC and BD of the first 2-D table Ta, the first representative value α and the second representative value β can be calculated using the following Equation 4.

[0090] [Equation 4]

[0091]

[0092] That is, the first representative value α is greater than the overall average for each individual. The representative value of each coefficient can be understood as each being greater than the overall average. The average of the coefficient values. Furthermore, the second representative value β is individually less than the overall average. The representative values ​​of the coefficients can be understood as each being less than the overall average. The average of the coefficient values.

[0093] The first representative value α and the second representative value β are also used to approximately restore the first compressed value to its original state.

[0094] Furthermore, a first representative value α is generated for each of the four block regions BA, BB, BC, and BD in the first 2-D table Ta. The second 1-D table MA is configured to include four first representative values ​​α for each of the four block regions BA, BB, BC, and BD, as well as block location information. Additionally, a second representative value β is generated for each of the four block regions BA, BB, BC, and BD in the first 2-D table Ta. The second 1-D table MB is configured to include four second representative values ​​β for each of the four block regions BA, BB, BC, and BD, as well as block location information.

[0095] The first compressed bitmaps BAC, BBC, BCC, and BDC generated by compression unit 44 can be as follows: Figure 5 It can be reconstructed into a compressed bitmap TaC in a manner corresponding to the first 2-D table Ta of the coefficients "a" of the entire image, and can be stored in the compressed bitmap storage unit 50.

[0096] The rearrangement unit 46 constructs a second 2-D table. In each second 2-D table, the first representative value and the second representative value of the shared block location information are used for each mapping in the four block regions BA, BB, BC and BD, respectively.

[0097] More specifically, the rearrangement unit 46 receives a second 1-D table MA and MB, which together include position information for each of the four block regions BA, BB, BC and BD, and have first representative values ​​MA1, MA2, MA3 and MA4 and second representative values ​​MB1, MB2, MB3 and MB4 for each block position.

[0098] like Figure 6 In this manner, rearrangement unit 46 constructs second 2-D tables TMA1, TMA2, TMA3, TMA4, TMB1, TMB2, TMB3, and TMB4 corresponding to the block location information of the second 1-D tables MA and MB.

[0099] A second 2-D table TMA1 is constructed by matching a first representative value MA1, which is mapped to the block location information of the block region BA of the second 1-D table MA for each pixel. More specifically, since the first representative value of the block region BA is MA1, the second 2-D table TMA1 is constructed such that the first representative value MA1 maps to all pixels. A second 2-D table TMB1 is constructed by matching a second representative value MB1, which is mapped to the block location information of the block region BA of the second 1-D table MB for each pixel. More specifically, since the second representative value of the block region BA is MB1, the second 2-D table TMB1 is constructed such that the second representative value MB1 maps to all pixels.

[0100] Each of the second 2-D tables TMA2 and TMB2 for the first representative value MA2 and the second representative value MB2 of block region BB, the second 2-D tables TMA3 and TMB3 for the first representative value MA3 and the second representative value MB3 of block region BC, and the second 2-D tables TMA4 and TMB4 for the first representative value MA4 and the second representative value MB4 of block region BD can also be constructed in the same way as the second 2-D tables TMA1 and TMB1 for the first representative value MA1 and the second representative value MB1 of block region BA.

[0101] Compression unit 48 receives Figure 6 The second 2-D table TMA1, TMA2, TMA3, TMA4, TMB1, TMB2, TMB3, and TMB4, and as follows: Figure 7 Perform a second compression on the second 2-D table as described above.

[0102] Compression unit 48 generates second compressed bitmaps TMAC1, TMAC2, TMAC3, TMAC4, TMBC1, TMBC2, TMBC3, and TMBC4 by calculating the difference between the current data and the next data in the consecutive data within the second 2-D tables TMA1, TMA2, TMA3, TMA4, TMB1, TMB2, TMB3, and TMB4, and mapping the second compressed value of the next data to the difference.

[0103] In this case, compression unit 48 can store the first data of each of the second 2-D tables TMA1, TMA2, TMA3, TMA4, TMB1, TMB2, TMB3 and TMB4 as the original, and can store the second compressed bitmaps TMAC1, TMAC2, TMAC3, TMAC4, TMBC1, TMBC2, TMBC3 and TMBC4 such that the number of bits of the difference after the first data is less than the number of bits of the first data.

[0104] Furthermore, the compression unit 48 can prevent error increase and propagation by using a method that calculates the difference between the current data and the next data of sequentially continuous data in the horizontal and vertical directions of the second 2-D tables TMAC1, TMAC2, TMAC3, TMAC4, TMBC1, TMBC2, TMBC3 and TMBC4.

[0105] The second compressed bitmaps TMAC1, TMAC2, TMAC3, TMAC4, TMBC1, TMBC2, TMBC3, and TMBC4 generated by compression unit 48 can be as follows: Figure 8 In a manner corresponding to the first 2-D table Ta of the coefficients “a” of the entire image, a compressed bitmap TMAC and TMBC are reconstructed for each representative value, and can be stored in the compressed bitmap storage unit 50.

[0106] According to the apparatus and method of the present invention for compressing the coefficient values ​​of a compensation equation used to compensate for defects in an image, adjacent data can be correlated because 1-D data is changed to 1-D data with the same ratio as the displayed image. Therefore, effective compression can be guaranteed.

[0107] Furthermore, while the transformation and compression process for one coefficient has been described in the embodiments of this disclosure, the compressed bitmap can be calculated by performing the transformation and compression on the remaining coefficients in the same manner. Therefore, the advantage of this disclosure is that it allows for flexible handling of sensitive parts when compensating for defects, since the degree of compression loss may differ for each coefficient.

[0108] This disclosure can reduce memory capacity because the coefficient values ​​of the compensation equation used to compensate for defects in each pixel in the image can be effectively compressed through two consecutive compressions.

[0109] Furthermore, according to this disclosure, compression can prevent artifacts from occurring between compressed regions within each block region. The coefficient values ​​of the compensation equation can be effectively compressed for each pixel in a manner that is correlated between adjacent pixels or blocks.

[0110] This disclosure can be configured to address defects in an image by compensating for the brightness of each pixel using a compressed value that has been effectively compressed as described above.

[0111] That is, the first compressed bitmap and the second compressed bitmap calculated using this disclosure can be stored in the driver. Figure 9 The driver 110 of the display panel 120 can compensate for defects in the image by using a first compressed bitmap and a second compressed bitmap to compensate for display data.

[0112] like Figure 9 In this process, display data is provided to timing controller 100. Timing controller 100 constructs a packet PKT for the display data and provides the packet to driver 110.

[0113] The driver 110 is configured to recover display data after receiving a packet, generate a source signal Sout corresponding to the display data, and provide the source signal to the display panel 120.

[0114] For example, Figure 9 The driver 110 in the middle can be as follows Figure 10 That's the configuration you'd expect.

[0115] Reference Figure 10 The driver 110 may include a packet receiving unit 200, a defect compensation unit 210, a source signal generation unit 220, a source signal output unit 230, a compressed bitmap storage unit 250, and a coefficient value generation unit 260.

[0116] The packet receiving unit 200 receives the packet PKT for display data provided by the timing controller 100 and recovers the display data from the packet PKT.

[0117] The defect compensation unit 210 has a structure for compensating defects based on the compensation equation of Equation 1 and compensates display data, thereby resolving defects by applying coefficient values ​​provided by the coefficient value generation unit 260 to each pixel.

[0118] The source signal generation unit 220 drives the source signal based on the compensated display data. The source signal output unit 230 provides the source signal Sout driven by the source signal generation unit 220 to the display panel 120.

[0119] The compressed bitmap storage unit 250 can be configured using a memory such as an EEPROM, and provides coefficient value generation unit 260 with reference to... Figures 2 to 8 The process described generates a first compressed bitmap and a second compressed bitmap. In this case, the first compressed bitmap and the second compressed bitmap can be provided for each block region.

[0120] The first compressed bitmaps BAC, BBC, BCC, and BDC have a first compressed value for the coefficients of the corresponding block region for each pixel. The second compressed bitmaps TMAC1 and TMBC1, TMAC2 and TMBC2, TMAC3 and TMBC3, and TMAC4 and TMBC4, respectively, corresponding to the block regions BA, BB, BC, and BD, have a second compressed value corresponding to a first representative value and a second representative value for each pixel.

[0121] The coefficient value generation unit 260 is configured to generate coefficient values ​​for a compensation equation for each pixel to compensate for defects in an image by using a first compression value of a first compressed bitmap and a second compression value of a second compressed bitmap, and to provide the coefficient values ​​of each pixel to the defect compensation unit 210.

[0122] More specifically, the coefficient value generation unit 260 first releases the compression of the second compressed bitmaps TMAC1 and TMBC1, TMAC2 and TMBC2, TMAC3 and TMBC3, and TMAC4 and TMBC4.

[0123] That is, the coefficient value generation unit 260 generates a second 2-D table for each block region of the second compressed bitmaps TMAC1 and TMBC1, TMAC2 and TMBC2, TMAC3 and TMBC3, and TMAC4 and TMBC4, respectively, having first representative values ​​MA1, MA2, MA3 and MA4 and second representative values ​​MB1, MB2, MB3 and MB4. In this case, by mapping the first data of the second compressed bitmap to the original and adding the current data and the next data of the continuous data, a second 2-D table with first representative value and second representative value for each pixel can be generated. When the second compressed bitmap and Figure 7 When the reverse order of the shown order corresponds to the order, a second 2-D table is generated.

[0124] In addition, the coefficient value generation unit 260 releases the compression of the first compressed bitmaps BAC, BBC, BCC and BDC.

[0125] That is, the coefficient value generation unit 260 calculates first representative values ​​MA1, MA2, MA3, and MA4 and second representative values ​​MB1, MB2, MB3, and MB4 for each pixel in the second 2-D tables TMA1 and TMB1, TMA2 and TMB2, TMA3 and TMB3, and TMA4 and TMB4, of the first compressed bitmaps BAC, BBC, BCC, and BDC.

[0126] In addition, the coefficient value generation unit 260 releases the compression of the first compressed values ​​of the first compressed bitmaps BAC, BBC, BCC and BDC based on the first representative values ​​MA1, MA2, MA3 and MA4 and the second representative values ​​MB1, MB2, MB3 and MB4.

[0127] Specifically, the coefficient value generation unit 260 can generate the coefficient value by mapping a first representative value of the corresponding block region when the first compression value is "1" and a second representative value of the corresponding block region when the first compression value is "0". Figure 3 The first 2D table has a recovered grayscale value for each pixel. That is, the coefficient value generation unit 260 can map the representative value that belongs to the first representative value and the second representative value and corresponds to the first compressed value to... Figure 4 The first compressed values ​​of the first compressed bitmaps BAC, BBC, BCC, and BDC are used to generate a first 2D table with coefficient values ​​for each pixel. This process is related to... Figure 3 The first 2-D table was compressed into Figure 4 The first compressed bitmaps BAC, BBC, BCC, and BDC correspond to each other in reverse order.

[0128] Furthermore, the coefficient value generation unit 260 can extract the coefficient value and position information of the image for each pixel by performing this process on each coefficient of the compensation equation.

[0129] As described above, according to this disclosure, the coefficient value generation unit 260 can provide coefficient values ​​with positional information about the coefficients.

[0130] The defect compensation unit 210 can perform compensation on the display data by substituting the compensation equation of Equation 1 into the coefficient value of the coefficient provided by the coefficient value generation unit 260 for each pixel as described above.

[0131] Therefore, the apparatus for compressing coefficient values ​​of a compensation equation for compensating defects in an image, according to this disclosure, can store and provide coefficient values ​​using a memory with a small capacity, and can prevent artifacts and compensate for defects very well by using a 2-D compressed bitmap with the same ratio as the compressed bitmap of the image based on compressed values ​​that are correlated between adjacent data.

Claims

1. An apparatus for compressing the coefficient values ​​of a compensation equation for compensating for defects in an image, the apparatus comprising: The coefficient value providing unit is configured to provide coefficient values ​​and position information for each pixel of the coefficients of the compensation equation used to compensate for defects in the image; as well as The coefficient value compression unit is configured to provide a first compressed bitmap and a second compressed bitmap by sequentially performing a first compression and a second compression on the coefficient values. Wherein, through the first compression, the coefficient value compression unit constructs a first two-dimensional table for the coefficient values ​​based on the location information, generates a first compressed bitmap having a first compressed value obtained by compressing the coefficient values ​​of the first two-dimensional table, and generates a representative value for recovering the first compressed value; and In this process, the coefficient value compression unit constructs a second two-dimensional table for the representative value based on the location information, and generates a second compressed bitmap having a second compressed value obtained by compressing the representative value of the second two-dimensional table.

2. The apparatus according to claim 1, wherein: The coefficient value providing unit constructs and provides the coefficient values ​​of the compensation equation, which is constructed as a quadratic expression, for each pixel, along with the position information, as a first one-dimensional table. The coefficient value compression unit divides the entire image into multiple block regions, sequentially performs the first compression and the second compression on each coefficient, and provides the first compressed bitmap and the second compressed bitmap.

3. The apparatus according to claim 1, wherein, The coefficient value compression unit includes: The first rearrangement unit is configured to construct the first two-dimensional table based on the position information and the coefficient values. The first compression unit is configured to calculate the total average value of the coefficient values ​​of the first two-dimensional table, generate the first compressed bitmap through the first compression, wherein the first compressed value is mapped to a preset value corresponding to a value that is greater than or less than the total average value of each of the coefficient values, and generate a first representative value and a second representative value for recovering the first compressed bitmap. The second rearrangement unit is configured to construct a second two-dimensional table based on the location information, wherein in each of the second two-dimensional table, the first representative value and the second representative value are mapped for each pixel; and The second compression unit is configured to calculate the difference between the current data and the next data in continuous data, and to generate the second compressed bitmap by mapping the second compressed value of the next data to the difference.

4. The apparatus according to claim 3, wherein, The first compression unit generates the first compression bitmap, in which the first compression value is mapped to "1" according to the coefficient values ​​being greater than the total average value, and the second compression value is mapped to "0" according to the coefficient values ​​being less than the total average value.

5. The apparatus according to claim 3, wherein, First compression unit: The first representative value is generated as the average of coefficients that are each greater than the total average, or as a value obtained by adding the first average standard deviation of the coefficients that are each greater than the total average to the total average. The second representative value is generated as the average of the coefficients that are each less than the total average value, obtained by subtracting the second average standard deviation of the coefficients that are each less than the total average value from the total average value.

6. The apparatus according to claim 3, wherein: The second compression unit stores the first data of the second two-dimensional table as an original, and The difference is stored after the first data, such that the number of digits is less than the number of digits in the first data, or Calculate the difference between the current data and the next data in the horizontal and vertical directions of the second two-dimensional table.

7. A method for compressing coefficient values ​​of a compensation equation for compensating for defects in an image, the method comprising: The first step involves receiving the coefficient value and position information of each of the coefficients in the compensation equation for each pixel, which is used as a first one-dimensional table. The compensation equation is constructed as a quadratic expression and used to compensate for defects in the image. as well as The second step is to divide the image into multiple block regions, sequentially perform first compression and second compression on each block region, and provide a first compressed bitmap and a second compressed bitmap. The first compression includes: Based on the location information, a first two-dimensional table is constructed for the coefficient values ​​of the first one-dimensional table; Calculate the total average of the coefficient values ​​of the first two-dimensional table, and generate a first compressed bitmap having a first compressed value obtained by compressing the coefficient values ​​of the first two-dimensional table, wherein the first compressed value is mapped to a preset value corresponding to a value greater than or less than the total average of each of the coefficient values; and Generate a first representative value and a second representative value for recovering the first compressed bitmap, and provide a second one-dimensional table that commonly includes the location information and has the first representative value and the second representative value, respectively. The second compression includes: A second two-dimensional table is constructed based on the location information, and in each of the second two-dimensional table, the first representative value and the second representative value of the second one-dimensional table are mapped to each pixel respectively; and The difference between the current data and the next data in continuous data is calculated, and a second compressed bitmap is generated having a second compressed value obtained by compressing the first representative value and the second representative value of the second two-dimensional table, wherein the second compressed value is mapped to the next data as the difference. The first compressed bitmap is generated by mapping the first compressed value to "1" based on the fact that each of the coefficient values ​​is greater than the total average value, and mapping the second compressed value to "0" based on the fact that each of the coefficient values ​​is less than the total average value.

8. An apparatus for compensating display data using compression values, the apparatus comprising: A compressed bitmap storage unit is configured to store and provide a first compressed bitmap having a first compressed value and a second compressed bitmap having a second compressed value corresponding to a first representative value and a second representative value for recovering the first compressed value. The coefficient value generation unit is configured to generate coefficient values ​​for a compensation equation for compensating defects in an image for each pixel based on the first compressed value of the first compressed bitmap and the second compressed value of the second compressed bitmap, and to provide the coefficient values ​​for each pixel. as well as The defect compensation unit is configured to receive display data for each pixel and the coefficient value, compensate the display data for each pixel using the compensation equation to which the coefficient value has been applied, and output the compensated display data. Wherein, the coefficient value generation unit: A second two-dimensional table with the first representative value and the second representative value is constructed for each pixel by mapping the first data to an element of the second compressed bitmap with the second compressed value and adding the current data and the next data of the continuous data. Based on the first compressed value of the first compressed bitmap for each pixel, one of the first representative value and the second representative value of the second two-dimensional table for each pixel is selected as a representative value, and a first two-dimensional table is generated in which the coefficient values ​​corresponding to the representative values ​​have been mapped for each pixel. The position information of each pixel and the coefficient value are provided as the first two-dimensional table. The first compressed value is obtained by compressing the coefficient values ​​of the first two-dimensional table, and the second compressed value is obtained by compressing the first representative value and the second representative value of the second two-dimensional table.

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