TWI755066B - Display overdrive compensation method and display device and handheld device using the same - Google Patents

Abstract

An overdrive compensation method for a display, comprising: performing a block operation in the vertical direction on each frame of input image data to obtain N blocks, wherein N is an integer greater than or equal to 1; A line segment detection operation is performed for each to obtain a line segment vector, each of which includes a length value and a brightness value; the line segment vectors in each of the blocks of the input image data of a current frame are combined with performing a luminance comparison operation on the line segment vectors in each of the sub-blocks of the input image data of the previous frame correspondingly, and generating an overdrive compensation indication flag according to the result of the luminance comparison operation; and in the When the overdrive compensation indication flag is in an active state, according to the luminance value in the line segment vector corresponding to two of the input image data of the current frame and the input image data of the previous frame Perform an overdrive compensation operation on the corresponding image data in the input image data of the current frame to output an overdrive compensated image data.

Description

Display overdrive compensation method and display device and handheld device using the same

The present invention relates to a display device, in particular to an overdrive compensation method and an overdrive compensation device for a display.

In recent years, flat panel displays have gradually replaced cathode ray tube displays (CRTs) and are widely used in various industries, becoming an indispensable component of most electronic devices (such as mobile phones, Pads, TVs, computers, etc.).

The response time of the panel is one of the important factors to measure the characteristics and quality of various panels. When the response time is too long, it will cause the phenomenon of motion smear on the screen. Observed at the edges of content such as strips, text, graphics, and GUIs.

Please refer to FIGS. 1a to 1d together, wherein FIG. 1a shows a schematic diagram of the motion smear phenomenon; FIG. 1b shows a block diagram of a conventional overdrive compensation device; FIG. 1c shows the conventional overdrive compensation of FIG. 1b A schematic diagram of a frame change situation in which the device generates leakage compensation; and FIG. 1d is a schematic diagram of a frame change situation in which the conventional overdrive compensation device of FIG. 1b generates miscompensation.

As shown in Figure 1a, the image data bit width is 8 bits (value range 0~255), the background gray level (Gray Level, GL) is 64, and there is a gray strip (GL192) in the screen vertically upward When scrolling, the edge of the strip moves from the position of Line A in the previous frame to the position of Line B in the current frame. If the panel response time is too long, there will be motion smear in the area between Line A and Line B.

In order to alleviate or suppress this phenomenon, the conventional over-drive compensation (Over-Drive Compensation) method has been proposed, which is to appropriately strengthen or weaken the driving voltage corresponding to the gray scale to be displayed, so as to shorten the response time and achieve an ideal output. Effect. In FIG. 1a, when the current frame is displayed, the grayscale value of each line between Line A and Line B is increased to 208, and then the driving voltage corresponding to the grayscale of 208 is applied to the pixels of the panel to improve the smear phenomenon.

In addition, as shown in FIG. 1b, a general overdrive compensation device uses an overdrive look-up table (LUT) 10 to obtain the overdrive compensation amount of the image data (for example, from GL64 The overdrive compensation amount changed to 192 is 16 (208 minus 192)). Since the image data of the current frame and the image data of the previous frame need to be used at the same time when looking up the table, all the image data of the previous frame will be stored in a frame buffer (Frame Buffer) 20 in advance. When processing the current frame Then read it out for comparison with the current frame image data and look up the table for use. However, as the display resolution increases, the required capacity of the frame register 20 also increases.

In order to reduce the capacity and bandwidth requirements of the frame register, it is necessary to encode and compress the image data of the current frame before storing. Accordingly, it is also necessary to decompress the encoding of the previous frame at the overdrive compensation end. Discrete Cosine Transform (DCT) can be used for coding and compression, but it is more complicated in hardware implementation, and when the compression ratio is high, the reconstructed image will have large distortion and the amount of compressed data is still quite large. , thus limiting the application level of driver chips that are very sensitive to circuit scale, storage capacity, bandwidth and power consumption.

As shown in FIG. 1c, the overdrive compensation device of FIG. 1b is used to calculate the average value (Average Picture Level, APL) of the image data in the unit of row (or block) when it cannot provide more storage capacity. And store it in the temporary register. When overdrive compensation is performed on the image data of the current frame, take out the APL value of the corresponding row (or block) of the previous frame and compare it with the current image data and look up the table to obtain the corresponding compensation. After the amount is added to the current image data to complete the overdrive compensation. Since each line (or block) only needs to store one APL value, the line buffer can be used to replace the larger frame register to reduce hardware resource consumption. However, because the entire line of image data It is only represented by one APL value, so it is inevitable that error compensation will occur.

As shown in Figure 1c, on the screen background (GL64), Line A has a GL128 horizontal bar Bar1 with a length equal to the image width (W), and Line B (Line B) has a GL192 with a length equal to half the image width (W/2) bar Bar2. When the previous frame switches to the current frame, the horizontal bar Bar1 moves vertically upward and covers the horizontal bar Bar2. The correct compensation result should be the downward compensation operation when the image data 192 to 128 on the left half of Line A change, and the upward compensation operation when the image data 64 to 128 on the right half change. Since the APL calculation value of Line B in the previous frame is 128, which is equal to all the image data on the horizontal bar Bar1, the driving processing will not be performed when the horizontal bar Bar1 moves to Line B, resulting in missing compensation (missing compensation). )Phenomenon.

As shown in Figure 1d, there are horizontal bars (Bar1 and Bar3) with a length of W/2 and a grayscale of 192 on the left side of Line A and Line B. When the horizontal bar at Line A is moved to Line B, the bar is covered by the horizontal bar. At Bar3, since the APL value of Line B in the previous frame is 128, the pixels on Bar1, which do not need to be driven, perform a downward compensation operation of 192 to 128, while the pixels on Bar2 perform a downward compensation operation of 64 to 128. Compensation operation upwards, resulting in the phenomenon of false compensation. Similarly, when common content such as text or patterns appear in a line, problems such as noise and distortion may also occur due to incorrect compensation.

To sum up, the conventional overdrive compensation method cannot solve the problem of reducing the storage capacity and avoiding the poor effect of the overdrive compensation at the same time.

In order to solve the above problems, a novel overdrive compensation method for a display is urgently needed in the art.

One objective of the present invention is to disclose an overdrive compensation method for a display, which can solve the problems of leakage compensation and false compensation in the prior art, so as to achieve the purpose of correctness of overdrive compensation.

Another object of the present invention is to disclose an overdrive compensation method for a display, which can simultaneously solve the goals of reducing storage capacity and correctness of overdrive compensation.

Another object of the present invention is to disclose an overdrive compensation method for a display, which can improve the smear phenomenon of the display screen of the display by correcting the overdrive compensation, so as to achieve the purpose of improving the visual effect.

In order to achieve the aforementioned object, an overdrive compensation method of a display is proposed to improve the smear phenomenon of a display screen of the display. The input image data is subjected to a vertical block operation to obtain N blocks, where N is an integer greater than or equal to 1; a line segment detection unit is used to perform a line segment detection operation on each of the N blocks to respectively Obtain line segment vectors, each of which includes a length value and a brightness value, and store the line segment vectors in a storage unit; use a judgment unit to store each segment of the input image data of a current frame The line segment vectors in the block and the line segment vectors in each of the sub-blocks of the input image data of the previous frame are correspondingly performed a luminance comparison operation, and an overdrive is generated according to the result of the luminance comparison operation compensation indicating flag, wherein when the input image of the current frame When the difference between the luminance values in the line segment vectors corresponding to the data and the two corresponding input image data of the previous frame is greater than a threshold, the overdrive compensation indicating flag will exhibit an active state; and When the overdrive compensation indication flag is in the active state, a compensation unit is used, according to the line segments corresponding to two of the input image data of the current frame and the input image data of the previous frame The difference of the luminance values in the vector performs an overdrive compensation operation on the corresponding image data in the input image data of the current frame to output an overdrive compensated image data. In addition, the present invention also discloses a display device and a handheld device utilizing the same.

In one embodiment, the size of each of the partitions is equal or unequal.

In one embodiment, the image data is a grayscale value of a pixel at the image location.

In one embodiment, it further includes a preprocessing step for performing a noise filtering operation on the image data in a vertical direction or a horizontal direction before the line segment detection operation.

In one embodiment, the line segment detection operation includes: Step 1. Each of the sub-blocks includes n rows and m columns of pixels, calculating the pixel average value A of each sub-block and each column, and determining a maximum number of line segments to be detected. M, where n, m and M are all natural numbers greater than or equal to 1; Step 2: Initialize a line segment vector of each of the blocks, each of the line segment vectors includes a luminance value GL, a length value LEN, a line The segment end column coordinate value EP and a weight value W, record a luminance average value gl of each starting column of the sub-blocks, and set a line segment counter k to 0, a line segment length counter len to 1, and a column counter i to be The number of columns of each sub-block is increased by 1; Step 3: Calculate the absolute value of the difference between the pixel average value of each column of each sub-block and the pixel average value of the adjacent previous column, if the absolute value of the difference value is When it is less than a first preset threshold, add 1 to the line segment length counter len; Step 4, if the line segment length counter len is greater than or equal to a second preset threshold, update the line segment vector as; GL=gl, LEN= len, W=1, EP=i-1; Step 5, add 1 to a counter k, and initialize a current line segment vector to 0; Step 6, reset the brightness average value gl to the pixel average value A and The line segment length counter is 1, and the column counter is incremented by 1; Step 7, judge whether the column counter is greater than or equal to the column value m, if not, go back to Step 3; and Step 8, judge whether the block counter k is greater than or equal to It is equal to the detected maximum number of line segments M. If yes, perform a reduction operation on the line segment vector of each block to obtain M line segment vectors, otherwise end.

In one embodiment, the reduction operation includes: arranging the line segment vectors of the respective blocks in descending order; and selecting the largest M line segment vectors and according to the line segment end point column coordinate value EP in them by: The order from small to large is used to reorder the M line segment vectors.

In one embodiment, the reduction operation includes: performing a merging factor operation on the current line segment and the adjacent next line segment on the line segment vector of each block to obtain a merging coefficient φ for each; The two adjacent line segments corresponding to the maximum value of , perform a merge operation to generate a new line segment vector; rearrange the line segment numbers; and decrement the block counter k by 1 to determine whether the block counter k is equal to M, if not, Then perform the combined factor operation again.

In addition, the present invention also provides a display device having the display and control circuit as described above, wherein the display is selected from the group consisting of an LCD display, an LED display, an electronic paper display and an OLED display a display.

In addition, the present invention also provides a handheld device, which has the above-mentioned display device, and the handheld device is a smart phone or a portable computer. In order to enable your examiners to further understand the structure, features and purposes of the present invention, drawings and detailed descriptions of preferred embodiments are attached.

10: Overdrive Lookup Table

20: Frame register

100: Display device

110: Display

120: Control circuit

200: Handheld

210: Central Processing Unit

220: Display device

Step a1: utilize a block unit to perform a block operation in the vertical direction on each frame of input image data to obtain N blocks, wherein N is an integer greater than or equal to 1

Step a2: utilize a line segment detection unit to carry out a line segment detection operation to each of the N sub-blocks to obtain a line segment vector, each of which includes a luminance value, a length value, a line segment end point column coordinate value and a line segment. weight value, and store these line segment vectors in a storage unit

Step a3: Utilize a judgment unit to use a judging unit to divide the ones of the blocks of the input image data of a current frame The line segment vector and the line segment vectors in each of the blocks of the input image data of the previous frame are correspondingly subjected to a luminance comparison operation, and an overdrive compensation indication flag is generated according to the result of the luminance comparison operation, Wherein, when the difference between the luminance values in the line segment vectors corresponding to two of the input image data of the current frame and the input image data of the previous frame is greater than a threshold, the process The drive compensation indicator flag will show an active state

Step a4: Using a compensation unit when the overdrive compensation indication flag presents the active state, according to the input image data of the current frame and the input image data of the previous frame corresponding to two The difference of the luminance values in the line segment vector performs an overdrive compensation operation on the corresponding image data in the input image data of the current frame to output an overdrive compensation image data

Step b1: Each sub-block includes n rows and m columns of pixels, wherein n and m are both natural numbers greater than or equal to 1, calculate the pixel average value A of each sub-block and each column, and determine a detection maximum line segment number M

Step b2: Initialize a line segment vector of each sub-block, and each of the line segment vectors includes a luminance value GL, a length value LEN, a line segment end point column coordinate value EP and a weight value W, and record the sub-blocks A luminance average value gl of each starting column and set a segment counter k to 0, a segment length counter len to 1 and a column counter i to add 1 to the column number of each sub-block

Step b3: Calculate the absolute value of the difference between the pixel average value of each row of the sub-blocks and the pixel average value of the adjacent previous row. If the absolute value of the difference value is less than a first preset threshold, the The line segment length counter len is incremented by 1

Step b4: If the line segment length counter len is greater than or equal to a second preset threshold, update the line segment vector to be; GL=gl, LEN=len, W=1, EP=i-1

Step b5: Increase a block counter k by 1, and initialize a current line segment vector to 0

Step b6: reset the luminance average value gl to the pixel average value A of the row and the line segment length counter to 1, and increment the row counter by 1

Step b7: Determine whether the column counter is greater than or equal to the column value m, if not, go back to step b3

Step b8: determine whether the block counter k is greater than or equal to the detected maximum line segment number M, if so, obtain M line segment vectors by a reduction operation on the line segment vectors of the described blocks, otherwise end

Step c1: Arrange the line segment vectors of the blocks in descending order

Step c2: Select the largest M line segment vectors and arrange them in ascending order of the line segment end point column coordinate values EP in them, so as to reorder the M line segment vectors

Step d1: Perform a merging factor operation of a current line segment and an adjacent next line segment on the line segment vector of each of the blocks to obtain a merging coefficient φ

Step d2: Perform a merge operation on the two adjacent line segments corresponding to the largest φ value to generate a new line segment vector

Step d3: Rearrange the line segment numbers

Step d4: Decrease the block counter k by 1, and judge whether the block counter k of the column is equal to M, if not, perform the merging factor operation again

FIG. 1a is a schematic diagram illustrating a motion smear phenomenon.

FIG. 1b shows a block diagram of a conventional overdrive compensation device.

FIG. 1c is a schematic diagram illustrating a situation of a frame change in which leakage compensation is generated by the conventional overdrive compensation device of FIG. 1b.

FIG. 1d is a schematic diagram illustrating a situation of a screen change causing the conventional overdrive compensation device of FIG. 1b to generate erroneous compensation.

FIG. 2 is a flowchart illustrating an embodiment of an overdrive compensation method for a display of the present invention.

FIG. 3 is a flowchart illustrating an embodiment of the line segment detection operation of the overdrive compensation method of the display device of the present invention.

FIG. 4a is a flowchart illustrating an embodiment of the reduction operation of FIG. 3 .

FIG. 4b is a flowchart illustrating another embodiment of the reduction operation of FIG. 3 .

FIG. 4c is a schematic diagram illustrating an embodiment of the overdrive compensation of FIG. 3 .

FIG. 5 is a block diagram illustrating an embodiment of the display device of the present invention.

FIG. 6 is a block diagram illustrating an embodiment of the handheld device of the present invention.

Please refer to FIG. 2 , which shows a flow chart of an embodiment of a display overdrive compensation method of the present invention. The method is implemented by a control circuit and used to improve the smear phenomenon of a display screen of the display.

As shown in FIG. 2, the overdrive compensation method of the display of the present invention includes:

Step a1: use a block unit to perform a block operation in the vertical direction on each frame of input image data to obtain N blocks, where N is an integer greater than or equal to 1;

Step a2: Use a line segment detection unit to perform a line segment detection operation on each of the N sub-blocks to obtain a line segment vector, each of which includes a length value, a brightness value, a line segment end point column coordinate value and a line segment. weight value, and store these line segment vectors into a storage unit;

Step a3: Using a judgment unit to compare the line segment vectors in each of the blocks of the input image data of a current frame with the line segments in each of the blocks of the input image data of the previous frame A luminance comparison operation is performed on each of the vectors correspondingly, and an overdrive compensation indication flag is generated according to the result of the luminance comparison operation, wherein, when the input image data of the current frame and the input image of the previous frame are When the difference between the luminance values in the two corresponding line segment vectors in the data is greater than a threshold, the overdrive compensation indicator flag will exhibit an active state; and

Step a4: Using a compensation unit when the overdrive compensation indication flag is in the active state, according to the corresponding two of the input image data of the current frame and the input image data of the previous frame The difference of the luminance values in the line segment vector performs an overdrive compensation operation on the corresponding image data in the input image data of the current frame to output an overdrive compensation image data.

In addition, in step a1, the size of each of the blocks may be equal or unequal, and each frame of input image data represents the pixel grayscale value of one frame of image.

In addition, in step a2, it may further include a preprocessing step for performing a noise filtering operation on the image data in a vertical direction or a horizontal direction before the line segment detection operation.

Please refer to FIG. 3 , which shows a flow chart of an embodiment of the line segment detection operation of the display overdrive compensation method of the present invention.

As shown in FIG. 3, the line segment detection operation of the display overdrive compensation method of the present invention includes:

Step b1: each of the sub-blocks includes n rows and m columns of pixels, calculate the pixel average value A _i of each of the sub-blocks and each column, and determine a detection maximum number of line segments M, where n, m and M are all greater than or A natural number equal to 1, as shown in equation (1), P ( i , j ) is the image data at coordinates ( i , j );

Step b2: Initialize a line segment vector of each sub-block, each of the line segment vectors includes a luminance value GL, a length value LEN, a line segment end point column coordinate value EP and a weight value W, and record the sub-blocks A luminance average value gl of each starting column and setting a segment counter k to 0, a segment length counter len to 1 and a column counter i to add 1 to the column number of each sub-block;

Step b3: Calculate the absolute value of the difference between the pixel average value of each column of each sub-block and the pixel average value of the adjacent previous column, if the absolute value of the difference value is less than a first preset threshold T _d , Increment the line segment length counter len by 1, as shown in equation (2):

B _i =| A _i - A _{i -1} | len = len +1 if B _i < T _d (2);

Step b4: if the line segment length counter len is greater than or equal to a second preset threshold T1 , update the line segment vector to be; GL=gl, LEN=len, W= ₁ , EP=i-1;

Step b5: increment a block counter k by 1, and initialize a current line segment vector to 0;

Step b6: reset the luminance average value gl to the pixel average value A of the row and the line segment length counter to 1, and increment the row counter by 1;

Step b7: determine whether the column counter is greater than or equal to the column value m, if not, go back to step b3; and

Step b8: Determine whether the block counter k is greater than or equal to the detected maximum number of line segments M, if so, perform a reduction operation on the line segment vectors of the blocks to obtain M line segment vectors, otherwise end.

Please refer to FIG. 4a , which shows a flowchart of an embodiment of the reduction operation of FIG. 3 .

As shown in Figure 4a, the reduction operation includes:

Step c1: Arrange the line segment vectors of the blocks in descending order; and

Step c2: Select the largest M line segment vectors and arrange them in ascending order of the line segment end point column coordinate values EP, so as to reorder the M line segment vectors.

For example, the line segment detection operation in Figure 3 yields the following 6 line segments, from which M=4 line segments should be selected:

LS ₀ ={1,6,3,1}, LS ₁ ={166,10,18,1}, LS ₂ ={122,15,39,1},

LS3 ₌ { 89,9,48,1 }, _LS4 ={ 55,11,63,1 }, LS5 ={ _4,7,71,1 };

Since LEN ₂ (=15)> LEN ₄ (=11)> LEN ₁ (=10)> LEN ₃ (=9)> LEN ₅ (=7)> LEN ₀ (=6), the longest 4 line segments are selected as LS ₂ , LS ₄ , LS ₁ , LS ₃ ;

Then arrange these 4 line segments according to the order of end point coordinates from small to large ( EP ₁ (=18)< EP ₂ (=39)< EP ₃ (=48)< EP ₄ (=63)) to obtain block K The corresponding line segment vector is: LS _{K ,0} ={166,10,18,1}, LS _{K ,1} ={122,15,39,1},

LS _{K ,2} ={89,9,48,1}, LS _{K ,3} ={55,11,63,1}.

Please refer to FIG. 4b , which shows a flowchart of another embodiment of the reduction operation of FIG. 3 .

As shown in Figure 4b, the reduction operation includes:

Step d1: perform a merging factor operation of a current line segment LS _t and an adjacent next line segment LS _{t +1} on the line segment vector of each of the blocks to obtain a merging coefficient φ, as shown in equation (3);

Among them, α is the magnification coefficient, and its value is between 1 and 30, but not limited to this. The first item is related to the difference between the brightness values of the two line segments. The smaller the difference, the more likely the merge; Relevant, the closer the distance, the more likely to merge.

Step d2: perform a merging operation on the two adjacent line segments LS _t and LS _{t +1} corresponding to the maximum value of each merging coefficient φ to generate a new line segment vector, as shown in equation (4);

Step d3: rearrange the number of each line segment, as shown in equation (5);

LS _q = LS _{q +1} , q = t +1,..., k -2 (5)

Step d4: Decrease the block counter k by 1, and judge whether the block counter k of the column is equal to M, and if not, perform the combining factor operation again.

For example, the line segment detection operation in Figure 3 yields the following 6 line segments, from which M=4 line segments should be selected:

LS ₀ ={1,6,3,1}, LS ₁ ={166,10,18,1}, LS ₂ ={122,15,39,1},

LS3 ₌ { 89,9,48,1 }, _LS4 ={ 55,11,63,1 }, LS5 ={ _4,7,71,1 };

Perform the merge factor operation of adjacent line segments (α value is 20)

φ ₀ ( LS ₀ , LS ₁ )=0.0918, φ ₀ ( LS ₁ , LS ₂ )=0.3584, φ ₀ ( LS ₂ , LS ₃ )=0.5882,

φ ₀ ( LS ₃ , LS ₄ )=0.4762, φ ₀ ( LS ₄ , LS ₅ )=0.3644

Among them, the coefficient φ(0.5882) corresponding to the line segments 2 and 3 is the largest, and the two line segments are combined according to step d2 to obtain

In step d3, the line segment numbers are rearranged as:

In step d4, the block counter k -1=5> M at this time, the merging factor operation is performed again, as shown below:

φ ₁ ( LS ₀ , LS ₁ )=0.0918, φ ₁ ( LS ₁ , LS ₂ )=0.2982, φ ₁ ( LS ₂ , LS ₃ )=0.3205,

φ ₁ ( LS ₃ , LS ₄ )=0.3633

線段合併後得到 Among them, the coefficient φ(0.3633) corresponding to the line segments 3 and 4 is the largest. According to step d2, these two

After the line segments are merged, we get

In step d3, the line segment numbers are rearranged as:

In step d4, at this time the block counter k -1=4= M , 4 line segment vectors are obtained:

Please refer to FIG. 4c , which is a schematic diagram of an application example of the overdrive compensation method of FIG. 3 .

As shown in Figure 4c, the image width is 720 pixels, and there are three gray bars in the middle of Line B at the previous frame moment: Bar5 (length 150, brightness 0), Bar6 (length 360, brightness 192) and Bar7 (length 150) , brightness 128), Bar4 and Bar8 on both sides are the background (brightness is 64), and Line A consists of three gray bars Bar1 to Composed of Bar3. Assuming that at the current frame moment, the three-segment gray bar on Line A moves to Line B, since the APL values of Line A and Line B are both 128, the overdrive compensation method based on APL in the prior art will not work at this time. cause leakage compensation. In contrast, the processing procedure of the overdrive compensation method of FIG. 3 of the present invention is as follows (assuming M=3, T _l =10):

The following three line segments are detected in Line A:

The following five line segments are first detected in Line B:

Then use the reduction algorithm shown in Figure 4b to reduce the five line segments detected in Line B to the following three (the reduction process is similar to the example in Figure 3, and will not be repeated):

Next, perform overdrive compensation processing for each graphic element in Line B, which includes calculating the corresponding compensation amount according to the overdrive lookup data table given in Table 1. In Table 1, the horizontal axis represents the current graphic element value, and the vertical axis represents the previous The frame corresponds to the luminance value of the line segment. The segment compensation for Line B is as follows:

1，則該段圖元補償後的亮度值為32+1=33； The upward compensation will be performed for the pixels whose bits are in the interval 0~174 when they change from 9 to 32. Since the luminance data 9 does not correspond to the node in the table, the compensation amount needs to be calculated by interpolation, such as bilinear interpolation (Table 1). In area A), the compensation amount is 4.313, and the compensation amount is multiplied by the weight 0.308 of the corresponding line segment in the previous frame to obtain the final compensation amount of the primitive in this segment of 4.313*0.308

1, the brightness value of this segment after compensation is 32+1=33;

For the graphic elements in the range of 180~239, the downward compensation will be performed when the changes from 192 to 32. The compensation amount can be directly obtained by looking up the table as -12, and the corresponding line segment weight is 1, so the final compensation amount is -12*1 =-12, the brightness value of this segment after compensation is 32-12=20;

For the primitives located in the interval 240~479, downward compensation will be performed when the change from 192 to 128. The compensation amount can be directly obtained by looking up the table as -18, and the corresponding line segment weight is 1, so the final compensation amount is -18*1= -18, the brightness value of this segment after compensation is 128-18=110;

For the primitives located in the interval 480~539, upward compensation will be performed when the change from 192 to 224 is performed. The compensation amount that can be directly obtained by looking up the table is 7, and the corresponding line segment weight is 1, so the final compensation amount is 7*1=7, then The brightness value of this segment after compensation is 224+7=231;

5，則該段圖元補償後的亮度值為224+5=229。 For the primitives located in the interval 545~719, upward compensation will be performed when the change from 119 to 224 is performed. Since the data 119 does not correspond to the nodes in the table, the compensation amount needs to be calculated by interpolation, such as bilinear interpolation (B in the table). area), the compensation amount is 15.281, and the compensation amount is multiplied by the weight 0.308 of the corresponding line segment in the previous frame to obtain the final compensation amount of the primitive in this segment of 15.281*0.308

5, the brightness value of this segment after compensation is 224+5=229.

According to this, the overdrive compensation of the primitives on all gray bars in Line B can be completed.

Please refer to FIG. 5 , which shows a block diagram of an embodiment of the display device of the present invention.

As shown in FIG. 5 , a display device 100 has a display 110 and a control circuit 120 .

The control circuit 120 is used to implement the overdrive compensation method.

In possible embodiments, the display 110 may be an LCD display, an LED display, an electronic paper display or an OLED display.

Please refer to FIG. 6 , which shows a block diagram of an embodiment of the handheld device of the present invention.

As shown in FIG. 6 , the handheld device 200 has a central processing unit 210 and a display device 220 .

The display device 220 is implemented by the display device 100 and has a display 110 and a control circuit 120 , the control circuit 120 is used to implement the overdrive compensation method, and the central processing unit 210 is used to communicate with the control circuit 120 .

In a possible embodiment, the handheld device 200 may be a smart phone or a portable computer.

By the design disclosed above, the present invention has the following advantages:

1. The overdrive compensation method of the present invention can solve the problems of leakage compensation and false compensation in the prior art, so as to achieve the purpose of correctness of the overdrive compensation.

2. The overdrive compensation method of the display of the present invention can simultaneously solve the purpose of reducing storage capacity and correctness of overdrive compensation.

3. The overdrive compensation method of the display of the present invention improves the smear phenomenon of the display screen of the display by correcting the overdrive compensation, so as to achieve the purpose of improving the visual effect.

What is disclosed in this case is a preferred embodiment, and any partial changes or modifications that originate from the technical ideas of this case and are easily inferred by those who are familiar with the art are within the scope of the patent right of this case.

To sum up, regardless of the purpose, means and effect of this case, it shows that it is completely different from the conventional technology, and its first invention is suitable for practical use, and indeed meets the patent requirements of the invention. Society is to pray for the best.

Step a1: utilize a block unit to perform a block operation in the vertical direction on each frame of input image data to obtain N blocks, wherein N is an integer greater than or equal to 1

Step a2: utilize a line segment detection unit to carry out a line segment detection operation to each of the N sub-blocks to obtain a line segment vector, each of which includes a luminance value, a length value, a line segment end point column coordinate value and a line segment. weight value, and store these line segment vectors in a storage unit

Step a3: Using a judging unit to compare the line segment vectors in each of the blocks of the input image data of a current frame with the line segments in each of the blocks of the input image data of the previous frame A luminance comparison operation is performed on each of the vectors correspondingly, and an overdrive compensation indication flag is generated according to the result of the luminance comparison operation, wherein, when the input image data of the current frame and the input image of the previous frame are When the difference between the luminance values in the two corresponding line segment vectors in the data is greater than a threshold, the overdrive compensation indication flag will show an active state

Step a4: Using a compensation unit when the overdrive compensation indication flag presents the active state, according to the input image data of the current frame and the input image data of the previous frame corresponding to two The difference of the luminance values in the line segment vector performs an overdrive compensation operation on the corresponding image data in the input image data of the current frame to output an overdrive compensation image data

Claims (8)

An overdrive compensation method for a display, for improving the smear phenomenon of a display screen of the display, is realized by a control circuit, the method comprises: using a block unit to perform vertical direction correction on each frame of input image data A block operation is performed to obtain N blocks, where N is an integer greater than or equal to 1; a line segment detection operation is performed on each of the N blocks by a line segment detection unit to obtain a line segment vector, and each line segment vector Both contain a length value and a brightness value, and store the line segment vectors in a storage unit; use a judgment unit to compare the line segment vectors in each of the blocks of the input image data of a current frame with the previous ones. The line segment vectors in each of the sub-blocks of the input image data of a frame respectively perform a luminance comparison operation, and generate an overdrive compensation indication flag according to the result of the luminance comparison operation. When the difference between the luminance values in the line segment vectors corresponding to the input image data of the current frame and the input image data of the previous frame is greater than a threshold, the overdrive compensation indication flag The flag will show an active state; and when the overdrive compensation indication flag is in the active state, a compensation unit is used according to the difference between the input image data of the current frame and the input image data of the previous frame performing an overdrive compensation operation on the corresponding image data in the input image data of the current frame to output an overdrive compensation image data based on the difference of the luminance values in the two corresponding line segment vectors; Wherein, the line segment detection operation includes: Step 1, each of the sub-blocks includes n rows and m columns of pixels, calculate the pixel average value A of each sub-block and each column, and determine a maximum number of detected line segments M, where n , m and M are all natural numbers greater than or equal to 1; step 2, initialize a line segment vector of each of the blocks, and each of the line segment vectors includes a brightness value GL, a length value LEN, and a line segment end point column coordinate A value EP and a weight value W, record a luminance average value gl of each starting column of each block, and set a segment counter k to 0, a segment length counter len to 1, and a column counter i to be the segment counter Add 1 to the number of columns in the block; Step 3: Calculate the average value of pixels in each column of each block and the average value of pixels in the adjacent previous column an absolute difference value, if the absolute value of the difference value is less than a first preset threshold, add 1 to the line segment length counter len; step 4, if the line segment length counter len is greater than or equal to a second preset threshold value When , update the line segment vector to: GL=gl, LEN=len, W=1, EP=i-1; Step 5, add 1 to a counter k, and initialize a current line segment vector to 0; Step 6, reset The brightness average value gl is the pixel average value A of the column and the line segment length counter is 1, and the column counter is incremented by 1; Step 7, determine whether the column counter is greater than or equal to the column value m, if not, go back to step 3; and step 8, judging whether the block counter k is greater than or equal to the detected maximum number of line segments M, if so, perform a reduction operation on the line segment vectors of the blocks to obtain M line segment vectors, otherwise end. The overdrive compensation method for a display according to item 1 of the claimed scope, wherein the size of each of the sub-blocks is equal or unequal. The overdrive compensation method for a display as described in claim 1, wherein the image data is a grayscale value of a pixel at the image position. The overdrive compensation method for a display according to claim 1, further comprising a preprocessing step for performing a noise on the image data in a vertical direction or a horizontal direction before the line segment detection operation filter operation. The overdrive compensation method for a display according to claim 1, wherein the reduction operation comprises: arranging the line segment vectors of the respective blocks in descending order; and selecting the largest M The line segment vectors are arranged in ascending order of the line segment end point column coordinate values EP contained therein, and are used to reorder the M line segment vectors. The overdrive compensation method for a display as described in claim 1, wherein the reduction operation comprises: performing a combining factor operation on the line segment vector of the respective sub-blocks with a current line segment and an adjacent next line segment to obtain Obtain a combined coefficient φ for each; Perform a merging operation on two adjacent line segments corresponding to the maximum value of each merging coefficient φ to generate a new line segment vector; rearrange the number of each line segment; and decrement the block counter k by 1, and determine whether the block counter k of the column is equal to M, if not, perform the combined factor operation again. A display device, which has a display and a control circuit, the control circuit is used for performing the overdrive compensation method of the display as described in any one of the claims 1 to 6, wherein the display is composed of an LCD A display selected from the group consisting of a display, an LED display, an electronic paper display and an OLED display. A handheld device is provided with the display device as described in item 7 of the application scope, and the handheld device is a smart phone or a portable computer.

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