TWI758872B - 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, determining a maximum number of line segments M for detection and performing a horizontal block division operation on each sub-block to obtain M sub-blocks, and each sub-block includes n Row and m columns of pixels, where M, n and m are all natural numbers greater than or equal to 1; step 2, calculate the pixel average value A of each column of each sub-block; step 3, initialize a line of each sub-block Segment vector, each of the line segment vectors includes a luminance value GL and a length value LEN, record a luminance average value gl of each starting column of each sub-block, and set a line segment length counter len to 1 and a column counter i Add 1 to the number of columns of the sub-blocks; step 4, calculate the absolute value of the difference between the pixel average value of each column of the sub-block and the pixel average value of the adjacent previous column, if the difference value is absolute When the value is less than a first preset threshold, add 1 to the line segment length counter len; Step 5, if the line segment length counter len is greater than the length value LEN, update the line segment vector as; GL=gl, LEN=len; Step 6. Reset the average value gl of the brightness to the pixel average value A of the column and the length counter of the line segment to 1, and add 1 to the counter i of the column; Step 7. Determine whether the counter i of the column is greater than or equal to the value m of the column, If yes, store the line segment vector, if no, go back to step 4; step 8, increment the block counter k by 1, and go back to step 2 until the block counter k is equal to the number M of sub-blocks.

In one embodiment, the line segment detection operation includes: step 1, determining a maximum number of line segments M for detection and performing a horizontal block division operation on each sub-block to obtain M sub-blocks. Each sub-block includes n rows and m columns of pixels, wherein M, n and m are all natural numbers greater than or equal to 1; step 2, calculate the pixel average value A of each column of each sub-block; step 3, initialize the A line segment vector of each sub-block, each of the line segment vectors includes a luminance value GL and a length value LEN, record a luminance average value gl of each starting column of each sub-block, and set a line segment length counter len to be 1 and a column counter i add 1 to the number of columns of the sub-blocks; step 4, calculate the absolute value of the difference between the pixel average value of each column of the sub-block and the pixel average value of the adjacent previous column, if If the absolute value of the difference is less than a preset threshold, add 1 to the line segment length counter len; step 5, if the line segment length counter len is greater than or equal to a second preset threshold value, update the line segment vector; step 6, repeat Set the average value of brightness gl to be the pixel average value A of the row and the line segment length counter to be 1, and add 1 to the row counter i; Step 7, determine whether the row counter i is greater than or equal to the row value m, and if so, store For the line segment vector, if not, go back to step 4; step 8, increment the block counter k by 1, and return to step 2 until the block counter k is equal to the number M of sub-blocks.

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 length value and a brightness value, and these line segment vectors are stored 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

Step b1: Determine a maximum number of line segments M for detection and perform a horizontal block operation on each sub-block to obtain M sub-blocks, and each sub-block includes n rows and m columns of pixels, wherein M, n and m are all is a natural number greater than or equal to 1

Step b2: Calculate the pixel average value A of each row of the sub-blocks

Step b3: Initialize a line segment vector of each sub-block, each of the line segment vectors includes a luminance value GL and a length value LEN, record a luminance average value gl of each starting column of each sub-block and set A segment length counter len is 1 and a column counter i is the number of columns of the sub-blocks plus 1

Step b4: 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 b5: If the line segment length counter len is greater than the length value LEN, update the line segment vector to be; GL=gl, LEN=len

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 add 1 to the row counter i

Step b7: Determine whether the column counter i is greater than or equal to the column value m, if so, store the line segment vector, if not, go back to step b4

Step b8: Increase the block counter k by 1, and return to step b2 until the block counter k is equal to the number of sub-blocks M

Step c1: determine a detection maximum line segment number M and perform a horizontal block operation on each sub-block to obtain M sub-blocks, each of which includes n rows and m columns of pixels, wherein M, n and m are all is a natural number greater than or equal to 1

Step c2: Calculate the pixel average value A of each row of the sub-blocks

Step c3: Initialize a line segment vector of each of the sub-blocks, each of the line-segment vectors includes a luminance value GL and a length value LEN, record a luminance average value gl of each starting column of the sub-blocks and set A segment length counter len is 1 and a column counter i is the number of columns of the sub-blocks plus 1

Step c4: 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 line segment is The length counter len is incremented by 1

Step c5: If the line segment length counter len is greater than or equal to a second preset threshold, update the line segment vector

Step c6: reset the luminance average value gl to the pixel average value A of the row and the line segment length counter to 1, and add 1 to the row counter i

Step c7: Determine whether the column counter i is greater than or equal to the column value m, if so, store the line segment vector, if not, return to step c4

Step c8: increase the block counter k by 1, and return to step c2 until the block counter k is equal to the number of sub-blocks M

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. 3a shows the flow of an embodiment of the line segment detection operation of the display overdrive compensation method of the present invention. picture.

FIG. 3b is a schematic diagram of an embodiment of the line segment detection operation of the sub-block 0 of FIG. 3a.

4a is a flowchart illustrating another embodiment of the line segment detection operation of the overdrive compensation method of the present invention.

FIG. 4b is a schematic diagram illustrating an embodiment of the line segment detection operation of the sub-block 0 of FIG. 4a.

FIG. 5 is a schematic diagram illustrating an embodiment of the overdrive compensation method of FIG. 4a.

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

FIG. 7 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 and a brightness value, and store these line segment vectors in 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: When the overdrive compensation indication flag is in the active state, use a compensation unit according to the difference between the input image data of the current frame and the input image data of the previous frame. The difference between the luminance values in the two corresponding line segment vectors 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 FIGS. 3a to 3b together, wherein FIG. 3a shows a flowchart of an embodiment of the line segment detection operation of the display overdrive compensation method of the present invention; and FIG. 3b shows the line segment detection operation 1 of the sub-block 0 of FIG. 3a Schematic diagram of the embodiment.

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

Step b1: Determine a maximum number of line segments M for detection and perform a horizontal block operation on each sub-block to obtain M sub-blocks, each of which includes n rows and m columns of pixels, wherein M, n and m are all is a natural number greater than or equal to 1;

Step b2: Calculate the pixel average value A of each row of the sub-blocks, as shown in equation (1), where P ( i,j ) is the image data at the coordinate ( i,j );

Step b3: Initialize a line segment vector of each sub-block, each of the line segment vectors includes a luminance value GL and a length value LEN, record a luminance average value gl of each starting column of each sub-block and set A segment length counter len is 1 and a column counter i is incremented by 1 for the number of columns of the sub-blocks;

Step b4: 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 T _d , Increase 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 b5: If the line segment length counter len is greater than the length value LEN, update the line segment vector as; GL=gl, LEN=len;

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 i by 1;

Step b7: determine whether the row counter i is greater than or equal to the row value m, if so, store the line segment vector, if not, return to step b4;

Step b8: Increase the block counter k by 1, and return to step b2 until the block counter k is equal to the number M of sub-blocks.

Assuming N=H/n, n=2 (that is, the image data is divided into H/2 blocks in the vertical direction), M=4 (that is, each block is divided into 4 sub-blocks in the horizontal direction), suppose Each sub-block includes 2 rows and 18 columns of pixels (ie, m =18 and n =2). As shown in Figure 3b, the line segment detection operation of sub-block 0 (ie, k = 0). In the figure, the first row i represents the column coordinates of each pixel, and the second row P ( i,j ) represents the luminance value of each pixel (shown in 8-bit data bits). Step 2, calculate the luminance average value A _i of the upper and lower rows of pixels column by column , i =0,...,17 (the third row in the figure); Step 3, initialize the line segment parameters of sub-block 0 LS ₀ ={ GL ₀ =0, LEN ₀ =0}, record the brightness average value of the starting column gl = A ₀ =1, and set the length counter len =1, the column counter i =1; Step 4 4, calculate the absolute value of adjacent average values difference B _i (the fourth row in the figure), and determine whether the absolute difference is less than the first preset threshold T _d to determine whether the length counter len is accumulated by 1 (the fifth row in the figure), and the first preset threshold threshold is T _d = 10 for example. A line segment of length 4 is detected at the first four column positions, but when the execution reaches the column position i = 5, the line segment is interrupted because B _i > T _d , step 5, update the line segment parameter LS ₀ ={ GL ₀ =1, LEN ₀ =4}, Steps 6 to 7, reset gl = A ₄ =37 and len =1, then proceed to the next column position ( i =5). Repeat the operation to the column position i = 16, and detect another line segment ( gl =166 , len =6), since this line segment is longer than the first line segment, update the line segment parameters LS ₀ ={ GL ₀ =166, LEN ₀ =6}. After computing all the columns in sub-block 0, the longest line segment parameter of the sub-block can be finally obtained as LS ₀ ={ GL ₀ =166, LEN ₀ =6}.

Please refer to FIGS. 4a to 4b together, wherein FIG. 4a shows a flowchart of another embodiment of the line segment detection operation of the display overdrive compensation method of the present invention; and FIG. 4b shows the line segment detection of the sub-block 0 of FIG. 4a A schematic diagram of an embodiment of the measurement operation.

As shown in FIG. 4a, the line segment detection operation of the display overdrive compensation method of the present invention includes:

Step c1: Determine a maximum number of line segments M for detection and perform a horizontal block operation on each sub-block to obtain M sub-blocks, each of which includes n rows and m columns of pixels, wherein M, n, and m are all is a natural number greater than or equal to 1;

Step c2: Calculate the pixel average value A of each row of the sub-blocks, as shown in equation (1), where P ( i,j ) is the image data at the coordinate ( i,j );

Step c3: Initialize a line segment vector of each sub-block, each of the line segment vectors includes a luminance value GL and a length value LEN, record a luminance average value gl of each starting column of each sub-block and set A segment length counter len is 1 and a column counter i is incremented by 1 for the number of columns of the sub-blocks, as shown in equation (2);

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

Step c4: 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 , set The line segment length counter len is incremented by 1;

Step c5: if the line segment length counter len is greater than or equal to a second _preset threshold T1 , update the line segment vector, as shown in equation (3);

Step c6: 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 i by 1;

Step c7: determine whether the row counter i is greater than or equal to the row value m, if so, store the line segment vector, if not, return to step c4;

Step c8: Increase the block counter k by 1, and return to step c2 until the block counter k is equal to the number M of sub-blocks.

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

_The line segment detection operation of FIG. 4a uses the second preset threshold T1 to limit the length of the detected line segment, so in each block, the line segment detection operation of FIG. 3a can always detect fixed M line segments, and the line segment of FIG. 4a The number of line segments detected by the detection operation may be less than M.

Assuming N=H/n, n=2 (that is, the image data is divided into H/2 blocks in the vertical direction), M=4 (that is, each block is divided into 4 sub-blocks in the horizontal direction), suppose Each sub-block includes 2 rows and 18 columns of pixels (ie, m =18 and n =2). As shown in Figure 4b, the line segment detection operation of sub-block 0 (ie, k = 0). In the figure, the first row i represents the column coordinates of each pixel, and the second row P ( i,j ) represents the luminance value of each pixel (shown in 8-bit data bits). Step 2, calculate the luminance average value A _i of the upper and lower rows of pixels column by column , i =0,...,17 (the third row in the figure); Step 3, initialize the line segment parameters of sub-block 0 LS ₀ ={ GL ₀ =0, LEN ₀ =0}, record the brightness average value of the starting column gl = A ₀ =1, and set the length counter len =1, the column counter i =1; Step 4 4, calculate the absolute value of adjacent average values difference B _i (the fourth row in the figure), and determine whether the absolute difference is less than the first preset threshold T _d to determine whether the length counter len is accumulated by 1 (the fifth row in the figure), and the first preset threshold threshold is T _d = 10 for example. After the new line segment is detected at column position i = 16, step 5 mixes the new line segment vector {166,6} with the previous line segment vector {1,4} to obtain the final line segment parameter LS ₀ ={100, 10}, this is the final line segment parameter of sub-block 0.

Please refer to FIG. 5 , which is a schematic diagram of an embodiment of the overdrive compensation method of FIG. 4 a .

Assuming the image width is 720 pixels, at the previous frame moment Line B is a gray bar Bar5 (length 480, brightness 160) in the middle, and the two sides are the background (brightness 64), while Line A consists of three segments of the same length (both 240) but with different brightness (32, 128 and 224, respectively) gray bars Bar1 to Bar3. At the current frame moment, the three gray bars on Line A move to Line B, and it is calculated that the APL values of Line A and Line B are both 128. At this time, the conventional APL-based overdrive compensation method will cause the Bar2 part Can not be compensated, and the Bar1 and Bar3 parts will be wrongly compensated. The processing procedure of the overdrive compensation method of FIG. 4a of the present invention is as follows (assuming M=6):

The following three line segments are detected in Line A:

The following three line segments are detected in Line B:

For the pixels located in the interval 0~119, the downward compensation will be performed when the change is from 64 to 32, and the pixels located in the interval 120~239 will be compensated downward when the change is from 160 to 32. The pixels located in the interval 240~479 will be compensated downward. The pixels in the range of 160 to 128 will be compensated downward, the pixels in the range of 480 to 599 will be compensated upward from 160 to 224, and the pixels in the range of 600 to 719 will be compensated upward from 64 to 224. Downward compensation when changing. Pixels on all gray bars within Line B are properly compensated.

It can be seen from the above description that the line segment parameter LEN can be used not only to find the longest line segment through a length comparison program during detection, but also to calculate the weight of the subsequent compensation amount, where the weight represents the amount of the line segment occupied in a sub-block. The larger the value is, the more the brightness value of the line segment can represent the overall brightness of the sub-block.

In addition, if the gain calculation step in the subsequent compensation amount calculation module is omitted, then when the line segment parameters are stored in the buffer, the information of LEN or W does not need to be stored, but only M brightness values are stored in each line The value GL can be used, in this case, the storage space will be further reduced.

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

As shown in FIG. 6 , 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. 7 , which shows a block diagram of an embodiment of the handheld device of the present invention.

As shown in FIG. 7 , 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 length value and a brightness value, and these line segment vectors are stored 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 (11)

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, determining a maximum number of line segments M for detection and performing a horizontal block division operation on each sub-block to obtain M sub-blocks, each of which includes n rows and m columns pixel, wherein M, n and m are all natural numbers greater than or equal to 1; step 2, calculate the pixel average value A of each column of each of the sub-blocks; step 3, initialize a line segment vector of each of the sub-blocks, each The line segment vectors all include a luminance value GL and a length value LEN, record a luminance average value gl of each starting column of each of the sub-blocks, and set a line segment length counter len to 1 and a column counter i to each of the Add 1 to the number of columns in the sub-block; Step 4: Calculate the pixel average value of each column of each sub-block and the pixel average value of the adjacent previous column an absolute value of the difference, if the absolute value of the difference is less than a first preset threshold, add 1 to the line segment length counter len; step 5, if the line segment length counter len is greater than the length value LEN, update the The line segment vector is; GL=gl, LEN=len; Step 6, reset the luminance average value gl to the pixel average value A of the column and the line segment length counter to 1, add 1 to the column counter i; Step 7, determine Whether the column counter i is greater than or equal to the column value m, if so, store the line segment vector, if not, go back to step 4; step 8, increment the block counter k by 1, and go back to step 2 until the block counter k is equal to The number of blocks is M. 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. 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 blocks of the input image data of a frame are respectively subjected to a luminance comparison operation, and an overdrive compensation indication flag is generated according to the result of the luminance comparison operation. , 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; and when the overdrive compensation indicator flag is in the active state, a compensation unit is used according to the input image data of the current frame and the input of the previous frame The difference between the luminance values in the two corresponding line segment vectors in the image data 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; wherein, the line segment detection operation includes: step 1, determining a maximum number of line segments M for detection and performing a horizontal block division operation on each sub-block to obtain M sub-blocks, and each of the sub-blocks includes n Row and m columns of pixels, wherein M, n and m are all natural numbers greater than or equal to 1; Step 2, calculate the pixel average value A of each column of each of the sub-blocks; Step 3. Initialize a line of each of the sub-blocks Segment vector, each of the line segment vectors includes a luminance value GL and a length value LEN, record a luminance average value gl of each starting column of each of the sub-blocks, and set a line segment length counter len to 1 and a column counter i Add 1 to the number of columns of each of the sub-blocks; Step 4: Calculate the absolute value of the difference between the average value of pixels in each column of each of the sub-blocks and the average value of pixels in the adjacent previous column, if the absolute value of the difference is absolute If the value is less than a first preset threshold, add 1 to the line segment length counter len; step 5, if the line segment length counter len is greater than or equal to a second preset threshold, update the line segment vector; step 6, reset the brightness The average value gl is the pixel average value A of the row and the line segment length counter is 1, and the row counter i is incremented by 1; Step 7, determine whether the row counter i is greater than or equal to the row value m, and if so, store the line segment vector, if not, go back to step 4; step 8, increment the block counter k by 1, and go back to step 2 until the block counter k is equal to the number M of sub-blocks. The overdrive compensation method of the display according to the claim 1 or 5 of the scope of application , wherein the sizes of the blocks are equal or unequal. The overdrive compensation method for a display described in item 1 of the scope of the patent application is used to improve the smear phenomenon of a display screen of the display, which is realized by a control circuit. 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 indication flag, wherein, 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 one When the overdrive compensation indication flag is at the threshold value, the overdrive compensation indication flag will show an active state; and when the overdrive compensation indication flag shows the active state, a compensation unit is used according to the input image data of the current frame and the previous The difference between the luminance values in the two corresponding line segment vectors in the input image data of the frame performs an overdrive compensation operation on the corresponding image data in the input image data of the current frame to obtain an overdrive compensation operation. Output an overdrive compensation image data; 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 of the sub-blocks and each column, and determine 1. Detect the maximum number of 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, each of the line segment vectors includes a brightness value GL, a A length value LEN, a line segment end point column coordinate value EP and a weight value W, record a luminance average value gl of each start column of each of the blocks, and set a line segment counter k to 0 and a line segment length counter len to 1 And a column counter i is the number of columns of each said block plus 1; Step 3, calculate the average value of pixels in each column of each said block and the pixel average value of 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 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 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 as described in claim 7, wherein the reduction operation comprises: arranging the line segment vectors of each of the 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 7, wherein the reduction operation comprises: performing a combining factor operation on the line segment vector of each of the sub-blocks with a current line segment and an adjacent next line segment to obtain a Obtain a merging 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 line segment numbers; and decrement the block counter k by 1, It is judged whether the column block counter k is equal to M, and if not, the merging factor operation is performed 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, 5 and 7 of the scope of application method, wherein the display is a display selected from the group consisting of an LCD 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 10 of the application scope, and the handheld device is a smart phone or a portable computer.

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