TW201404119A - Overdrive device - Google Patents

Abstract

An overdrive device includes a training unit, an analysis unit, and a contrast adjusting unit. The training unit establishes a luminance difference table having R2 pieces of luminance differences, wherein each of the R2 pieces of luminance differences indicates a luminance difference between a measured display luminance value, driven in such a way that each of first and second view angle images correspond to any one of R gray levels, and a target luminance value. The analysis unit obtains a lookup luminance difference by means of looking up the luminance difference table according to first pixel data of the first view angle image and second pixel data, corresponding to a same pixel position as the first pixel data, of the second view angle image, and accordingly obtains an indication of luminance difference. The contrast adjusting unit has gray levels of the second view angle image partially adjusted according to the indication of luminance difference, so as to achieve headroom for overdrive operation.

Description

Overdrive

The present invention relates to an overdrive device, and more particularly to an overdrive device for use in an Active Shutter Three Dimensional System.

In today's fast-changing technology era, Three Dimensional (3D) display technology has been developed to enhance people's audio-visual entertainment. In general, the Active Shutter 3D system is a widely used 3D display technology. For example, the active shutter is a 3D system including shutter glasses and a display. The display alternately outputs display screens corresponding to the left eye angle of view and the right eye angle of view during the left eye and right eye display periods; the shutter glasses correspondingly shield the user's right eye line of sight during the left eye and right eye display periods And the left eye line of sight. Accordingly, the active shutter type 3D system can effectively provide display images of different viewing angles for the left and right eyes of the user, thereby achieving a 3D display effect.

However, in the existing active shutter type 3D system, the display needs to alternately display two different viewing angles of the viewing angle, so that the liquid crystal molecules in the display are faced with insufficient reaction time and corresponding crosstalk. Based on this, how to provide a driving mechanism that can effectively overcome the problems of poor response of liquid crystal molecules to poor display quality for active shutter type 3D systems is one of the directions that the industry is constantly striving for.

According to a first aspect of the present disclosure, an overdrive device is proposed for use in an Active Shutter Three Dimensional System to drive adjacent and sequentially triggered first and second viewing angles of the display. During the display period, the first and second viewing angle images are respectively displayed. Each of the first and second viewing angle images has a grayscale value range R, and R is a natural number greater than one. The overdrive device includes a training unit, an analysis unit, a contrast adjustment unit, and an overdrive unit. The training unit establishes a brightness difference lookup table having R ² pen brightness difference values, and each R ² pen brightness difference value respectively indicates that the first view image corresponds to any value of the gray scale value range R and the second view image corresponds to When any of the grayscale value ranges R, the measured difference between the measured brightness value and the target brightness value is displayed. The analyzing unit sequentially receives the first and second viewing angle input image data, and queries the first and second pixel data corresponding to the same pixel position in the image data according to the first and second viewing angles to query the brightness difference reading table. Correspondingly, a query brightness difference value is found; the analyzing unit further generates a brightness difference indicator for each pixel position according to the query brightness difference value. The contrast adjustment unit converts the brightness difference adjustment index corresponding to each pixel position to obtain a brightness difference adjustment gain value, and performs gray scale value adjustment for the second pixel data to find the corrected pixel data. The overdrive unit drives the display by providing an overdrive voltage based on the corrected pixel data.

In order to better understand the above and other aspects of the present invention, the preferred embodiments are described below, and in conjunction with the drawings, the detailed description is as follows:

The overdrive device proposed in this embodiment strives to realize the operation room of the overdrive operation by performing partial contrast reduction on the second view image data.

Please refer to FIG. 1 , which is a block diagram of an overdrive device according to an embodiment. The overdrive device 1 of the present embodiment is applied to an Active Shutter Three Dimensional System (not shown), wherein the active shutter stereoscopic display system includes shutter glasses and a display. The overdrive device 1 drives the display to display the first and second view images respectively during the adjacent and sequentially triggered first and second view display periods. For example, the first view image and the second view image are, for example, a left-eye view image and a right-eye view image, respectively, and each of the pen-shaped image data in the first view image selectively has an R-order gray-scale value GL(0). , GL(1), ..., GL(R-1), each of the pixel data in the second view image also selectively has an R-order gray-scale value range GL(0)-GL(R-1), Where R is a natural number greater than one.

The shutter glasses respectively shield the right eye line of the user and shield the left eye line of sight of the user during the first and second viewing angle display periods. In this way, the left and right eyes of the user can respectively receive the first and second viewing angle images corresponding to different viewing angles, thereby implementing a three-dimensional (3D) display effect.

The overdrive device 1 includes a training unit 110 for measuring the actual display brightness of the display in a training phase to find that the first view image corresponds to any gray scale value GL(0)-GL(R -1) When the second view image corresponds to any gray scale value GL(0)-GL(R-1), the R ² pen of the display actually displays the brightness LR(0,0)-LR(R-1, R-1) and the corresponding R ² pen target display brightness LT(0,0)-LT(R-1,R-1) R ² pen brightness difference LD(0,0)-LD(R-1, R-1), and according to the establishment of the brightness difference table Table_L, as shown in Figure 2. For example, the luminance difference lookup table Table_L is used according to the first view image corresponding to any value GL(0)-GL(R-1) of the grayscale value range R and corresponding to the grayscale value range R. The second view image of any of the values GL(0)-GL(R-1) is mapped to obtain a corresponding one of the pen brightness differences LD(0,0)-LD(R-1, R-1).

The overdrive device 1 further includes an analysis unit 120, a contrast adjustment unit 130, and an overdrive unit 140 for referring to the luminance difference table Table_L in a driving phase to detect the pixels in the first and second view images. The grayscale value of the data is analyzed, numerically adjusted, and mapped to an overdrive voltage to overdrive the display. Next, an example will be given to further explain the operation of the overdrive device 1 in this training phase and in this driving phase.

Training phase

In the training phase, the training unit 110 performs driving and brightness measurement operations for the display to generate a luminance difference look-up table Table_L.

Please refer to FIG. 3, which is a detailed block diagram of the training unit 110 of the present embodiment. The training unit 110 includes a first driving module 111, a second driving module 113, a brightness measuring module 115, and a computing module 117.

The first driving module 111 provides the first test view image data Fr1 and the second test view image data Fr2 corresponding to the same gray scale value to drive the display in the first and second viewing angle measurement periods TPr_1 and TPr_2, respectively. As shown in Figure 4A. For example, the first and second test view image data Fr1 and Fr2 all correspond to the gray scale value GL(j), and in the first and second view measurement periods TPr_1 and TPr_2, the display correspondingly displays the target display. Luminance value LT(j,j), where j is a natural number less than or equal to R. For example, the target display luminance value LT(j, j) is, for example, a value obtained by integrating the luminous intensity I(j) in the period TPr_1, which can be expressed as a diagonal block in FIG. 4A.

The second driving module 135 provides the third test view image data Fr3 and the fourth test view image data Fr4 corresponding to different gray scale values to drive the display in the third and fourth viewing angle measurement periods TPr_3 and TPr_4, respectively. Figure 4B shows. For example, the third and fourth test view image data Fr3 and Fr4 respectively correspond to the gray scale values GL(i) and GL(j), and in the fourth view measurement period TPr_4, the display correspondingly displays the actual display. Luminance value LR(i,j), where i is a natural number less than j and less than or equal to R. The actual display luminance value LR(i,j) is, for example, a value obtained by integrating the luminous intensity in the period TPr_4, which can be represented by the minus sign block in FIG. 4B, and the luminance difference value LD(i, j). ) can be represented by a plus sign area in Figure 4B.

The brightness measurement module 117 measures the display brightness value of the display in the first view measurement period TPr_1 to measure the target display brightness value LT(j, j). Similarly, the brightness measurement module 117 measures the display brightness value of the display in the fourth view measurement period TPr_4 to measure the actual display brightness value LR(i, j).

The calculation module 119 receives the target display brightness value LT(j,j) and the actual display brightness value LR(i,j), and subtracts the actual display brightness value LR(i,j) from the target display. The luminance value LT(j,j) is thereby used to find the luminance difference value LD(i,j).

Please refer to FIGS. 5A and 5B for a timing diagram of another brightness change of the display of the embodiment. In another example of operation, the parameter j' is substantially smaller than the parameter i', and the brightness change timing diagram for this display is as shown in Figures 5A and 5B. Accordingly, the training unit 110 of the present embodiment can effectively find the luminance difference value LD(i', j') via the operation of the aforementioned module in the training unit 110.

By adjusting the parameters i and j and driving the foregoing module to repeatedly perform the operations thereof, the training unit 110 of the present embodiment can effectively find all the corresponding R ² pen brightness differences LD(0, 0)-LD(R -1, R-1), to establish a brightness difference table Table_L correspondingly.

In the present embodiment, the case where the training unit 110 establishes a single luminance difference lookup table Table_L is taken as an example. However, the training unit 110 of this embodiment is not limited thereto. In other examples, the training unit 110 may also use a luminance difference substantially greater than zero (ie, an actual display luminance according to the polarity of the luminance difference value LD(0,0)-LD(R-1, R-1). An operation example in which the value LR(i, j) is higher than the target display luminance value LT(j, j) is stored in the luminance excess sub-table Table_+, and the luminance difference value substantially smaller than zero (that is, the actual display luminance) An operation example in which the value LR(i, j) is lower than the target display luminance value LT(j, j) is stored in the insufficient brightness look-up table Table_-.

Drive phase

In the driving phase, the overdrive device 1 refers to the luminance difference look-up table Table_L to perform an overdrive operation for this display.

Please refer to Figure 1 again. The analyzing unit 120 sequentially receives the first and Inputting the image data F1 and F2 from the second angle of view, and finding the first and second pixel data P1(x, y) and P2(x, y) corresponding to the same pixel position (x, y), wherein The horizontal resolution and the vertical resolution of the input image data F1 and F2 of the first and second viewing angles are respectively equal to the natural numbers m and n greater than 1, respectively, and x and y are natural numbers less than or equal to m and less than or equal to n, respectively. The first and second pixel data P1(x, y) and P2(x, y) correspond, for example, to gray scale values GL(a) and GL(b), respectively, where a and b are non-negative integers less than or equal to R .

The analyzing unit 120 queries the luminance difference lookup table Table_L according to the grayscale values GL(a) and GL(b) to correspondingly find the query luminance difference value LDO_(x, y). The analyzing unit 120 further generates a luminance difference index LDO_ind(1,1) for each pixel position (1,1)-(m,n) according to the numerical relationship between the query luminance difference value LDO_(x, y) and the threshold value LD_th. -LDO_ind(m,n).

Please refer to FIG. 6 , which is a detailed block diagram of the analysis unit 120 . For example, the analysis unit 120 includes a look-up table module 121, an indicator generation sub-module 122, a cluster sub-module 123, and an interpolation operation sub-module 124. The look-up table module 121 queries the brightness difference lookup table Table_L according to the first and second pixel data P1(x, y) and P2(x, y) to find the pen corresponding to the display position (x, y). Query the luminance difference LDO_(x, y). The look-up table module 121 further adjusts the parameters x and y to find the corresponding m×n pen query brightness difference LDO_(1,1)-LDO_ for all pixel positions (1,1)-(m,n). (m, n).

The indicator generation sub-module 122 compares the query brightness difference values LDO_(1,1)-LDO_(m,n) obtained by the look-up table with the threshold value LD_th to find the m×n pen numerical index LDO_n (1). , 1) - LDO_n (m, n). For example, when the luminance difference LDO_(x, y) is substantially greater than or equal to the threshold LD_th The numerical index LDO_n(x, y) corresponds to the value 1. For example, the luminance difference value LDO_(x, y) larger than the threshold value DL_th occurs in a case where the difference between the grayscale values GL(a) and GL(b) is large, such as GL(a) and GL( b) A case where the maximum grayscale value GL(R-1) and the minimum grayscale value GL(0) are respectively approached.

In contrast, when the luminance difference value LDO_(x, y) is substantially smaller than the threshold value LD_th, the numerical index LDO_n(x, y) corresponds to the value 0. For example, the luminance difference value LDO_(x, y) smaller than the threshold value DL_th occurs in the case where the values of the gray scale values GL(a) and GL(b) are close, such as GL(a) and GL(b). Both are close to the maximum grayscale value GL(R-1) or both are close to the minimum grayscale value GL(0).

In this way, through the operation of the indicator generation sub-module 122, the analysis unit 110 can efficiently select the pixel data whose luminance difference is greater than the threshold DL_th, and correspondingly give the weight value 1.

The cluster sub-module 123 divides the numerical index LDO_n(1,1)-LDO_n(m,n) into a plurality of statistical partitions R1, R2, ..., Rw according to their corresponding pixel positions, wherein each statistical partition R1- Rw further includes a plurality of statistical sub-partitions SR1, SR2, ..., SRz, where w and z are natural numbers greater than one. For example, w and z are equal to 256 and 9, respectively, and a schematic diagram of each statistical partition R1-R256 and its statistical sub-partitions SR1-SR9 can be as shown in FIG.

For each of the statistical sub-partitions SR1-SRz, the cluster sub-module 123 sums the plurality of numerical indicators corresponding to the respective pixel positions to obtain the cumulative numerical indicator Status(SR1)-Status(SRz). For example, the aforementioned summing operation can be expressed by the following equation (1):

The above operation is repeated to calculate a corresponding one-digit cumulative value indicator Status(SR1)-Status(SRz) for each of the statistical sub-partitions SR1-SRz in each of the statistical partitions R1-Rw.

For each of the statistical partitions R1-Rw, the cluster sub-module 123 finds one of the maximum cumulative numerical indicators of the z cumulative numerical index Status(SR1)-Status(SRz) corresponding to the z statistical sub-partitions SR1-SRz, and Use it as the statistical value indicator Status(R1)-Status(Rw). For example, the aforementioned operation of determining the statistical value indicator Status(R1)-Status(Rw) can be expressed by the following equation (2):

Accordingly, through the foregoing operation, the cluster sub-module 123 finds the w-statistic indicator Status(R1)-Status(Rw) for the statistical partitions R1-Rw, respectively.

The interpolation operation sub-module 124 interpolates the luminance difference indicator LDO_ind(1,1)-LDO_ind(m, according to the statistical value indicator Status(R1)-Status(Rw) of the statistical partition R1-Rw for each pixel position interpolation. n). For example, the interpolation operation sub-module 124 is configured to interpolate the statistical value indicators Status(R1)-Status(Rw) of each statistical partition R1-Rw via a bilinear interpolation step to obtain each picture. The luminance difference index LDO_ind(1,1)-LDO_ind(m,n) of the prime position (1,1)-(m,n).

The contrast adjustment unit 130 converts the luminance difference index LDO_ind(1,1)-LDO_ind(m,n) corresponding to each pixel position (1,1)-(m,n) to obtain a luminance difference adjustment gain value Gain. (1,1)-Gain(m,n), and accordingly adjust the grayscale value for the second pixel data P2(1,1)-P2(m,n) to find the corrected pixel data P2' (1,1)-P2'(m,n).

The overdrive unit 140 drives the display by providing an overdrive voltage based on the corrected pixel data P2'(1,1)-P2'(m,n).

For example, the luminance difference adjustment gain value Gain(x, y) and the luminance difference index LDO_ind(x, y) have a linear correspondence as shown in FIG. 8; and the corrected pixel data P2'(x, y) And the second pixel data P2(x, y) has a linear correspondence as shown in FIG. Referring to FIGS. 8 and 9, it can be seen that for the second pixel data P2(x, y) which is substantially close to the highest grayscale value GL(R-1), the corresponding corrected pixel data P2' ( The value of x, y) is correspondingly reduced, and for the second pixel data P2(x, y) substantially close to the lowest gray level value GL(0), the corresponding corrected pixel data P2' The value of (x, y) is correspondingly increased. In contrast, for the pixel data of the second pixel data P2(1,1)-P2(m,n) which is close to the intermediate value GL(R/2), the contrast adjustment unit 130 maintains its corresponding correction picture. The linear correspondence of the prime data P2'(x, y).

In other words, after the operation of the contrast adjusting unit 130, the grayscale value range of the corrected pixel data P2'(x, y) is adjusted from the original GL(0)-GL(R-1) to the reduced grayscale value. Range GL'(0)-GL'(R-1). In this way, even in the contrast adjusting unit 130 of the present embodiment, it is effective to draw the grayscale value close to the maximum value or the minimum value only for the second pixel data P2(1,1)-P2(m,n). In the case where the local data is subjected to local contrast reduction, the grayscale value range GL(0) to GL'(0) and the grayscale values GL(R-1) to GL'(R-1) are obtained. Overdrive operation space between. That is to say, compared with the conventional overdrive device, the overdrive device of the present embodiment has the possibility of additionally vacating without performing global (Global) contrast adjustment for the pixel data P2(x, y). The advantage of overdriving the operating space.

In conclusion, the present invention has been disclosed in the above preferred embodiments, and is not intended to limit the present invention. A person skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

1‧‧‧Overdrive

110‧‧‧ training unit

120‧‧‧Analysis unit

130‧‧‧Contrast adjustment unit

140‧‧‧Overdrive unit

111‧‧‧First drive module

113‧‧‧Second drive module

115‧‧‧Brightness measurement module

117‧‧‧Computation Module

121‧‧‧Checklist module

122‧‧‧ indicator generation sub-module

123‧‧‧ cluster sub-module

124‧‧‧Interpolation submodule

FIG. 1 is a block diagram of an overdrive device in accordance with an embodiment.

FIG. 2 is a schematic diagram of a luminance difference lookup table Table_L according to an embodiment.

FIG. 3 is a detailed block diagram of the training unit 110 of the present embodiment.

A timing diagram of a brightness change of the display of Figures 4A and 4B.

A timing diagram of another brightness change of the display of Figures 5A and 5B.

FIG. 6 is a detailed block diagram of the analysis unit 120.

Figure 7 shows a schematic diagram of the statistical partitions R1-Rw and its sub-partitions SR1-SRz.

FIG. 8 is a schematic diagram showing the correspondence relationship between the luminance difference adjustment gain value Gain(x, y) and the luminance difference index LDO_ind(x, y).

Fig. 9 is a diagram showing the correspondence between the corrected pixel data P2'(x, y) and the second pixel data P2(x, y).

1‧‧‧Overdrive

110‧‧‧ training unit

120‧‧‧Analysis unit

130‧‧‧Contrast adjustment unit

140‧‧‧Overdrive unit

Claims (7)

An overdrive device is applied to an Active Shutter Three Dimensional System to drive a display in an adjacent and sequentially triggered one of the first and second viewing angles, respectively Displaying a first and a second view image, each of the first and second view images having a grayscale value range R, and R is a natural number greater than 1, the overdrive device comprising: a training unit for establishing a luminance difference LUT having R ² T luminance difference value, each of the R ² T when the luminance difference value respectively corresponding to a first view image to the gray level value in any one range R and the second image corresponding to the viewing angle One of the displays displays a brightness difference between the brightness value and a target brightness value, and an analysis unit for sequentially receiving a first and a second Entering the image data from the viewing angle, and querying the brightness difference table according to the first and second pixel data corresponding to one of the same pixel positions in the first and second viewing angle input images to correspondingly find a stroke Query brightness difference And the analyzing unit further generates a brightness difference indicator for each pixel position according to the query brightness difference value; and a contrast adjusting unit converts the brightness difference indicator to obtain a brightness difference adjustment according to the brightness difference indicator corresponding to each pixel position a gain value, and accordingly, gray scale value adjustment is performed for the second pixel data to find a corrected pixel data; and an overdrive unit provides an overdrive voltage to drive the display according to the modified pixel data. The overdrive device of claim 1, wherein the training unit comprises: a first driving module for respectively providing corresponding gray scales during the first and second viewing angle measurement periods; a first test view image data and a second test view image data drive the display; a second drive module for providing corresponding to the gray in a third and a fourth view measurement period The third test view image data and the second test view image data drive the display; the brightness measurement module is configured to measure the display during the second view measurement period One of the targets displays a brightness value, and measures an actual display brightness value of one of the displays during the fourth viewing angle measurement period; and a calculation module for calculating a difference between the actual and the target display brightness values to find The brightness difference value is derived, and the brightness difference table is established accordingly. The overdrive device of claim 2, wherein the brightness difference look-up table includes a brightness value under-sub-table and a brightness excess sub-table, when the actual display brightness value is substantially lower than the target display When the brightness value is used, the calculation module stores the brightness difference value in the brightness value insufficiency sub-table; wherein, when the actual display brightness value is substantially higher than the target display brightness value, the computing module compares the brightness The difference is stored in the brightness excess sub-table. The overdrive device of claim 1, wherein the overdrive device The analysis unit includes: a look-up table module, configured to query the brightness difference lookup table according to the first pixel data and the second pixel data to find a brightness difference of the query corresponding to the display position And an indicator generating sub-module for comparing the brightness difference values of the plurality of query queries obtained by the look-up table with a threshold value to correspondingly find a numerical index; a cluster sub-module for The numerical indicators are divided into a plurality of statistical sub-partitions according to the corresponding pixel positions, and a cumulative numerical index is obtained according to the plurality of numerical values in the statistical sub-partitions; the cluster sub-module further includes the statistical sub-modules The partition is divided into a plurality of statistical partitions according to the display positions of the statistical sub-partitions, and a statistical value index is found according to the plurality of cumulative numerical indicators corresponding to the plurality of statistical sub-partitions of the statistical partitions; and an interpolation The operation sub-module obtains the brightness difference indicator according to the plurality of pixel positions according to the plurality of pixel statistical value indicators of the statistical partitions. The overdrive device of claim 4, wherein when the query brightness difference values are substantially greater than the threshold value, the statistical module setting corresponds to the numerical index having a first value, When the query brightness difference is substantially smaller than the threshold value, the statistical module sets the corresponding numerical index to have a second value. The overdrive device of claim 1, wherein the brightness difference indicator corresponding to each pixel position is adjusted with the brightness difference value. The gain values correspond to each other via a linear function. The overdrive device of claim 1, wherein the modified pixel data is a linear function of the brightness difference adjustment gain value.