WO2006062159A1 - Video data processing device, liquid crystal display device using the same, display device drive device, display device drive method, program thereof, and recording medium - Google Patents

Abstract

When a gradation transition amount exceeds a threshold value, a modulation unit (34) executes an interpolation calculation by referencing a lookup table (35), corrects video data D (i, j, k) of the current frame, and outputs it. When the gradation transition amount is lower than the threshold value, the modulation unit (34) outputs the video data D (i, j, k) of the current frame itself. Furthermore, the lookup table stores values used for calculating D2 (i, j, k) by the interpolation corresponding to the previous frame video data D0 (i, j, k-1) and the current frame D (i, j, k), if the gradation shift is above the threshold, which values are neither D (i, j, k) nor D0 (i, j, k-1). Thus, it is possible to realize an image display device capable of reducing the circuit size and the improving the display quality with a preferable balance.

Description

 Specification

 VIDEO DATA PROCESSING DEVICE, LIQUID CRYSTAL DISPLAY DEVICE INCLUDING THE SAME, DISPLAY DEVICE DRIVE DEVICE, DISPLAY DEVICE DRIVE METHOD, PROGRAM THEREOF, AND RECORDING MEDIUM

 Technical field

 [0001] The present invention relates to a video data processing apparatus for processing video data indicating a gradation of a pixel.

A video data processing device capable of balancing reduction in circuit scale and improvement in display quality at a higher level, a liquid crystal display device including the same, a drive device for the display device, a drive method for the display device, and a program and The present invention relates to a recording medium.

 Background art

 [0002] In addition to space-saving 'power saving features, liquid crystal display devices have recently been improved in performance such as viewing angle' contrast 'color reproducibility' response speed, etc., and are now becoming image display devices that surpass cathode ray tubes. . Therefore, the application of liquid crystal display devices to TVs and OA monitors (computer monitors) is expected to continue to expand.

 [0003] Normally, when a voltage is applied to a liquid crystal cell, the major axis direction (director) of the liquid crystal material (liquid crystal molecules) in the liquid crystal cell is changed by its dielectric anisotropy. Since the liquid crystal material has optical anisotropy, when the direction is changed, the polarization direction of the light transmitted through the liquid crystal cell also changes. The amount of light transmitted through the liquid crystal cell is controlled by an applied voltage (applied voltage) applied to the liquid crystal cell with the action of a polarizing plate provided in the liquid crystal cell. As a result, the luminance of each pixel can be set to the gradation luminance to be displayed, and image display can be performed.

However, a certain amount of time is required for the liquid crystal material to respond to changes in the applied voltage (the response speed of the liquid crystal material is slow). For example, in the case of TN (Twisted Nematic), IPS (In- Plane—Switc hing), or VA (Vertically Aligned) in the currently widely used liquid crystal display method (liquid crystal display mode), the response speed of the liquid crystal material is , 30msec ~ 50msec between slow gradations. Therefore, the response speed corresponding to 60 Hz (about 16.6 msec) of NTSC (National Television System Committee) signal or 50 Hz (20.0 msec) of PAL (Phase Alteration by Line) signal cannot be realized. Therefore, higher performance is needed to meet the demand for further market expansion.

 [0005] Therefore, conventionally, liquid crystal display devices have been developed in which liquid crystal materials and display driving methods are devised to increase the response speed.

 [0006] For example, in Patent Document 1 (Japanese Patent Laid-Open No. 10-39837; publication date: February 13, 1998), a voltage larger than the voltage difference corresponding to the gradation change is applied. In addition, a liquid crystal display device using “overshoot driving” in which a liquid crystal material is sharply moved to a target gradation is disclosed. In overshoot drive, the applied gradation value to be applied to the liquid crystal material in correspondence with the start gradation (current gradation) and the target gradation (desired gradation) (or the applied voltage that realizes the applied gradation) Prepare a look-up table (LUT) that defines (value) in advance and apply voltage based on this.

 [0007] Here, there is a problem that if an LUT storing a value corresponding to an applied voltage value corresponding to all patterns of gradation change is prepared, the capacity of a memory storing the LUT is significantly increased. Invite you.

 [0008] In order to solve this problem, Patent Document 2 (Japanese Patent Laid-Open No. 2004-4629; published date: January 8, 2004), as shown in FIG. Receives gradation data and measurement data from the temperature sensor 108, and performs interpolation calculation while referring to multiple LUTs stored in the LUT memory 112 to target gradation data required for gradation display. A liquid crystal display device including an applied gradation value acquisition unit 113 that calculates gradation data is disclosed. In this configuration, high-accuracy target gradation data (interpolated values) can be obtained by interpolation using local coordinates while taking into account various additional conditions.

 [0009] However, the configuration of Patent Document 2 described above achieves a significant reduction in the circuit scale as compared with a configuration storing all patterns, but compared with a configuration storing all patterns. Then, the display quality resulting from the interpolation calculation will occur to some extent. Therefore, it is required to further improve the display quality within a range that does not increase the circuit scale so much. Disclosure of the Invention

[0010] An object of the present invention is to reduce the circuit scale and improve the display quality at a higher level. It is to realize a display device.

 [0011] In order to achieve the above object, a video data processing apparatus according to the present invention repeatedly stores video data indicating the gradation of a certain pixel, and stores the video data storage apparatus until the next time. Based on the previous video data read from the video data storage device and the current video data, correction is made to emphasize gradation transition from the gray level indicated by the previous video data to the gray level indicated by the current video data. Correction means capable of outputting the corrected video data, wherein the correction means corresponds to a predetermined combination of possible combinations of the previous and current video data. The difference between the gradations indicated by the parameter storage device storing the meter for determining the corrected video data corresponding to the combination and the input video data is determined in advance. If a parameter corresponding to an input combination that is a combination of the values of both video data is not stored in the parameter storage device, a plurality of parameters are read from the parameter storage device. The parameters are read, and the parameters corresponding to the input combinations are calculated by interpolation based on these parameters to generate the corrected video data. If the threshold is not exceeded, the current video data is not corrected. The parameter storage device corresponds to a specific combination in which the gradations indicated by the values constituting the combination are the same among the predetermined combinations described above. As a parameter, the gradation indicated by the corrected video data determined by the parameter is the specific set. In addition to any of the gradations indicated by the values constituting the combination, and when the difference between the gradations indicated by the values constituting the input combination exceeds the threshold value, the parameter corresponding to the input combination is determined by the interpolation calculation. It is characterized by memorizing parameters for calculation.

 [0012] In the above configuration, when the difference between the gradations indicated by the input video data exceeds a predetermined threshold, the video data processing apparatus corrects the corrected video in which the gradation transition is emphasized. Since the data can be output, the response speed of the pixel of the display device that displays the video data can be improved.

[0013] Further, the interpolation means performs the gradation transition when the amount of gradation transition does not exceed the threshold value. Since emphasis is not performed, the following malfunctions, that is, when a still image is displayed, for example, the gradation transition that slightly occurs due to the influence of noise or the like is emphasized, and an unwanted gradation transition is generated by the user. It is possible to prevent the occurrence of a problem of being visually recognized.

 [0014] Further, the parameter storage device stores only parameters corresponding to a part of the combinations of values that can be taken by the current and previous video data, and the parameters corresponding to the remaining combinations are interpolated. Therefore, the circuit size can be greatly reduced compared to storing parameters corresponding to all combinations in the parameter storage device.

 [0015] Further, in the parameter storage device, the following parameters, that is, the gradations indicated by the corrected video data determined by the parameters constitute the specific combination corresponding to the specific combination. In order to calculate the parameter corresponding to the input combination by the interpolation operation when the difference between the gradations indicated by the values constituting the input combination exceeds the threshold value in addition to any of the gradations indicated by the value. The parameters are stored. Therefore, corresponding to a specific combination in which no gradation transition occurs, it is caused by approximation using an interpolation operation as compared with a configuration in which the shift of the gradation indicated by the value constituting the specific combination is stored. The error can be reduced, and the display quality when displayed on the display device can be improved.

 As a result, it is possible to realize a display device in which the reduction in circuit scale and the improvement in display quality are balanced at a higher level.

 [0017] When the parameters as described above are stored corresponding to the specific combination, if the interpolation calculation is used when the amount of gradation transition is equal to or less than the threshold value, the approximation using the interpolation calculation is used. There is a possibility that an error caused by the error becomes large. However, the interpolation means does not perform gradation transition enhancement when the amount of gradation transition does not exceed the threshold value. Therefore, when the amount of gradation transition is less than or equal to the threshold value, the error does not occur, and the deterioration in display quality due to the error can be prevented.

[0018] Further, in order to achieve the above object, the display device driving device according to the present invention includes a correction unit that corrects and outputs video data indicating gradation of a certain pixel that is repeatedly input, Outputs the signal corresponding to the later video data to the data signal line connected to the pixel Driving means for the display device including the output means for performing the input repeatedly

When the video data before correction is D (n-1), D (n) and the corresponding video data after correction is D2 (n-1), D2 (n), the correction means When the gradation transition amount of the video data before correction is larger than a predetermined threshold L, the corrected video data D2 (n) is D2 (n) = a + k '[(D (n — 1) — D (n)] is output, and the correction means outputs D2 (n) as the corrected video data D2 (n) when the gradation transition amount of the video data before correction is less than the threshold L. (n) = D (n) is output, and a is set to a value different from D (n).

In this configuration, when the gradation transition amount of the video data before correction is larger than a predetermined threshold value, D2 (n) = _a + k ′ as the corrected video data D2 (n) When ((D (n-1)-1 D (n)) is output and the gradation transition amount of the uncorrected video data is less than the threshold L, the corrected video data D2 (n) is D2 (n) = D (n) is output, and α is set to a value different from D (η).

 [0020] Therefore, as with the video data processing device, any of the following configurations, that is, no gradation transition occurs !, any of the gradations indicated by the values constituting the specific combination corresponding to the specific combination: Compared with a configuration that stores information, errors caused by approximation using interpolation calculation can be reduced, and display quality when displayed on a display device can be improved. As a result, it is possible to realize a display device that balances reduction in circuit scale and improvement in display quality at a higher level.

 [0021] Still other objects, features, and advantages of the present invention will be sufficiently enhanced by the following description. The advantages of the present invention will become apparent from the following description with reference to the accompanying drawings.

 Brief Description of Drawings

 FIG. 1, showing an embodiment of the present invention, is a block diagram showing a main configuration of a modulation drive processing unit.

 FIG. 2 is a block diagram showing a main configuration of an image display device including the modulation drive processing unit.

FIG. 3 is a circuit diagram showing a configuration example of a pixel of the image display device. FIG. 4 is a diagram showing output video data stored in a lookup table of the modulation drive processing unit.

 FIG. 5 is a diagram showing a combination of previous and current frame video data in which corresponding output video data is stored in the lookup table.

 FIG. 6 is a graph showing the relationship between the ideal characteristics of the output video data and the output video data generated by the interpolation calculation.

 FIG. 7, showing another embodiment of the present invention, is a diagram showing output video data stored in a lookup table of the modulation drive processing unit.

 FIG. 8, showing still another embodiment of the present invention, is a block diagram showing a main configuration of a modulation drive processing unit.

 FIG. 9 is a block diagram showing a conventional technique and showing a configuration of a liquid crystal display device. Explanation of symbols

 [0023] 1 · la ~: Lb image display device (liquid crystal display device)

 21 · 21a-21b Modulation drive processing unit (video data processing device)

 31 Frame memory (video data storage device)

 35 · 35a Look-up table (parameter storage device)

 34 '34a to 34b Modulation processing unit (interpolation means)

 V video data value (parameter)

 VI -V2 video data value (first and second parameters)

 VI -V2a Video data value difference (first and second parameters)

 BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment]

One embodiment of the present invention is described below with reference to FIGS. That is, the image display apparatus according to the present embodiment interpolates the values stored in the look-up table (LUT) when the gradation transition amount from the previous time to the current time is larger than a predetermined threshold value, and When the tone transition is emphasized and is equal to or less than a predetermined threshold, the image display device emphasizes the tone transition, and can interpolate more appropriately without increasing the circuit scale of the lookup table. As shown in FIG. 2, the panel 11 of the image display device 1 includes a pixel array 2 having pixels PIX (1,1) to PIX (n, m) arranged in a matrix, and a pixel array 2 Are provided with a data signal line driving circuit 3 for driving the data signal lines SL1 to SLn and a scanning signal line driving circuit 4 for driving the scanning signal lines GLl to GLm of the pixel array 2. Further, the image display device 1 includes a control circuit 12 that supplies control signals to the two drive circuits 3 and 4, and the control circuit 12 that emphasizes the gradation transition based on the input video signal. And a modulation drive processing unit (video data processing device) 21 for modulating the video signal to be supplied to. These circuits are operated by supplying power from the power supply circuit 13.

 [0026] Hereinafter, before explaining the detailed configuration of the modulation drive processing unit 21 as a drive device of the display device, the overall configuration and operation of the entire image display device (liquid crystal display device) 1 will be described. In addition, for convenience of explanation, it is necessary to specify the position by referring to the position with a numeral or alphabetic character only when it is necessary to specify the position, for example, the data signal line SLi of the square. In cases such as “!” Or generically, reference is made by omitting the characters indicating the position.

 [0027] The pixel array 2 includes a plurality (in this case, n) of data signal lines SLl to SLn and a plurality of data signal lines SLl to SLn (in this case, m). Scanning signal lines GLl to GLm, where j is an arbitrary integer up to 1 force n and any integer from 1 to m is j, an image for each combination of data signal line SLi and scanning signal line GLj. Element PIX (i, j) is provided. In this embodiment, each pixel PIX (U) includes two adjacent data signal lines SLG-1) 'SLi and two adjacent scanning signal lines GL (j-1)' GLj. Arranged in the part surrounded by! Speak.

 [0028] The image display device 1 according to the present embodiment is a liquid crystal display device, and the pixel PIX (i, j) has a gate serving as a switching signal line GLj, for example, as shown in FIG. To the field effect transistor SW (i, j) whose drain is connected to the data signal line SLi, and the pixel capacitance Cp (i, j) whose one electrode is connected to the source of the field effect transistor SW (i, j). ). The other end of the pixel capacitor Cp (i, j) is connected to a common electrode line common to all the pixels PIX. The pixel capacitor Cp (i, j) includes a liquid crystal capacitor CL (i, j) and an auxiliary capacitor Cs (i, j) that is added as necessary.

[0029] In the pixel PIXGJ), when the scanning signal line GLj is selected, a field effect transistor SW (i, j) becomes conductive, and the voltage applied to the data signal line SLi is applied to the pixel capacitor Cp (i, j). On the other hand, while the selection period of the scanning signal line GLj ends and the field effect transistor SW (i, j) is cut off, the pixel capacitor Cp (i, j) continues to hold the voltage at the cut-off. Here, the transmittance or reflectance of the liquid crystal varies depending on the voltage applied to the liquid crystal capacitance CL (i, j). Therefore, if the scanning signal line GLj is selected and a voltage corresponding to the video data D to the pixel PIX (i, j) is applied to the data signal line SLi, the display state of the pixel PlX (iJ) is It can be changed according to data D.

 The image display device 1 according to the present embodiment is a vertical alignment mode liquid crystal cell as a liquid crystal cell used for the pixel array 2, that is, when no voltage is applied, the liquid crystal molecules are aligned substantially perpendicular to the substrate. A liquid crystal cell in which the liquid crystal molecules tilt from the vertical alignment state according to the voltage applied to the liquid crystal capacitance CL (i, j) of the pixel ΡΙΧ (ί, χ) is used, and the liquid crystal cell is normally black mode (voltage When no voltage is applied, the mode is black.

 In the above configuration, the scanning signal line drive circuit 4 shown in FIG. 2 outputs a signal indicating whether or not the selection period is valid, such as a voltage signal, to each of the scanning signal lines GL1 to GLm. Further, the scanning signal line drive circuit 4 changes the scanning signal line GLj that outputs a signal indicating the selection period based on timing signals such as a clock signal GCK and a start pulse signal GSP supplied from the control circuit 12, for example. ing. Thus, the scanning signal lines GLl to GLm are sequentially selected at a predetermined timing.

 [0032] Further, the data signal line driving circuit 3 extracts the video data D ... to each pixel PIX ... inputted in time division as the video signal DAT by sampling at a predetermined timing, respectively. . Further, the data signal line driving circuit 3 sends each data signal line SL l to each pixel PIX (l, j) to PIX (n, j) corresponding to the scanning signal line GLj selected by the scanning signal line driving circuit 4. Through ~ SLn, output signals corresponding to the video data D to each are output.

 Note that the data signal line drive circuit 3 determines the output timing of the sampling timing output signal based on timing signals such as the clock signal SCK and the start pulse signal SSP input from the control circuit 12. Decide.

On the other hand, each of the pixels PIX (l, j) to PIX (n, j) is given to the data signal lines SL1 to SLn corresponding to the pixels PIX (l, j) to PIX (n, j) while the scanning signal line GLj corresponding to the pixels PIX (l, j) to PIX (n, j) is selected. Depending on the output signal Then, adjust the transmittance and determine your own brightness.

 Here, the scanning signal line driving circuit 4 sequentially selects the scanning signal lines GLl to GLm.

 Therefore, all the pixels PIX (1,1) to PIX (n, m) of the pixel array 2 can be set to the brightness (gradation) indicated by the video data D to each image, and the image displayed on the pixel array 2 Can be updated.

 Note that the video data D may be the gradation level itself or a parameter for calculating the gradation level as long as the gradation level of the pixel PIX (i, j) can be specified. In the following, a case where the video data is the gradation level of the pixel PIX (U) will be described as an example.

 [0037] Further, the video signal DAT given to the modulation drive processing unit 21 from the video signal source VSO to the image display device 1 may be transmitted in frame units (whole screen units). However, one frame may be divided into a plurality of fields and may be transmitted in units of the field. In the following, the case of transmission in units of fields will be described as an example.

 That is, according to this embodiment, the video signal DAT supplied from the video signal source VSO to the modulation drive processing unit 21 divides one frame into a plurality of fields (for example, two fields) and It is transmitted in field units.

 More specifically, when the video signal source VSO transmits the video signal DAT to the modulation drive processing unit 21 of the image display device 1 via the video signal line VL, all video data for a certain field is transmitted. After transmission, video data for each field is transmitted in a time-sharing manner, such as by transmitting video data for the next field.

 [0040] Further, the field is composed of a plurality of horizontal lines. For example, in the video signal line VL, after all video data for a certain horizontal line is transmitted in a certain field, the field is transmitted next. The video data for each horizontal line is transmitted in a time-sharing manner, such as by transmitting video data for the horizontal line.

In this embodiment, one frame is composed of two fields, and in the even field, the video data of the horizontal line of the even-numbered row among the horizontal lines constituting one frame is transmitted. . In the odd field, the video data of the odd horizontal line is transmitted. Sarako, the above video signal source VSO transmits video data for one horizontal line. In this case, the video signal line VL is time-division driven, and each video data is sequentially transmitted in a predetermined order.

 Here, as shown in FIG. 1, the modulation drive processing unit 21 according to the present embodiment includes a frame memory (video data storage device) 31 for storing video data for one frame up to the next frame, and a basic Specifically, the video data D (i, j, k) of the current frame FR (k) input to the input terminal T1 is written to the frame memory 31 and the video of the previous frame FR (k-1) is written from the frame memory 31. Based on the memory control circuit 32 that reads out and outputs the data DO (i, j, kl) and the both video data D (i, j, k) -DOG.jk-l), the both video data D ( i, j, k) -DOG.jk-l), the decision processing unit 33 for determining whether or not gradation transition enhancement is necessary. Based on (i, j, k) -DOG.jk-l), the current frame FR (k) power at the pixel PIX (i, j) is emphasized to the gradation transition to the previous frame FR (kl). Current frame FR (k) video data D ( i, j, k) is corrected and output.If not required, the modulation processing unit (interpolation means) 34 for outputting the video data D (i, j, k) itself and the modulation processing unit 34 correct the output. And a look-up table (LUT; parameter storage device) 35 to be referred to when performing the process.

 [0043] In the following, the signal output from the modulation processing unit 34 is referred to as an output video signal DAT2 regardless of the presence or absence of correction, and the video data D out of the output video data D2 constituting the output video signal DAT2 Data corresponding to (i, j, k) and D0 (i, j, k-1) is referred to as output video data D2 (i, j, k). Further, in each part of the image display device 1, the output video data D2 (i, j, k) is included in the output video data D2 (i, j, k) regardless of whether the signal, data, voltage, or luminance exists at the same time. On the basis of the voltage applied to the pixel PIX (i, j) as the voltage of the current frame FR (k) and the frame to which the voltage is applied as the current frame FR (k). The luminance at which j) reaches the end of the current frame FR (k) is called the luminance of the current frame FR (k).

[0044] The LUT 35 basically includes the values (gradations) of the video data D (i, j, k-1) of the previous frame FR (k-1) and the current frame FR (k ) Of video data D (i, j, k) with possible values (gradation), for each of the predetermined combinations, a corrected value to be output when the combination is input Output video data D2 (i, j, k) is stored. Here, the value stored in the LUT 35 is determined by the characteristics of the pixel array 2. The In the present embodiment, when a voltage corresponding to the second gradation is applied to the pixel PIX (U) in a state where the brightness of the pixel PIX (U) is at the brightness indicated by the first gradation, the voltage is applied. When the pixel PIX (i, j) reaches the luminance indicated by the third gradation at the end of the frame, the LUT 35 basically has a combination of the first gradation and the third gradation. Corresponding to, data indicating the second gradation is stored.

As an example, in the present embodiment, the values that can be taken by the video data DO and the video data D of the previous frame are 0 to 255, respectively, and the LUT 35 is a combination of both as shown in FIG. As shown in FIG. 5, when the area specified in is divided into 8 × 8 small areas, video data D2 corresponding to the four corner points of each small area is stored. In this example, the above area is a two-dimensional space from (0, 0) to (255, 255), so when divided into 8 X 8 small areas, each small area has 32 gradations X It becomes a 32 gradation area. Therefore, in this case, 9 × 9 points that are the combination power of gradations every 32 gradations are stored in the LUT 35.

 [0046] When the correction is instructed from the determination processing unit 33, the modulation processing unit 34 performs linear interpolation between the video data D2 corresponding to each combination stored in the LUT 35, and actually performs the interpolation. The video data D2 corresponding to the combination of the input previous frame representative value DO (i, j, kl) and video data D (i, j, k) can be calculated and output.

 More specifically, the modulation processing unit 34 according to the present embodiment receives the combination (S, E) of both the video data DO (i, j, kl) and D (i, j, k). Then, it is specified to which of the above small areas as the combination force calculation area. Further, the modulation processing unit 34 sets the arrival gradations at the four corners of the calculation area as A, B, C, and D in the order of the upper left corner, the upper right corner, the lower right corner, and the lower left corner, respectively. Y XX, and the difference between the combination of the upper left corner (SO, E0) and the above combination (S, E) to (1, 1) is (Ay, Δχ) = ((S- S0) / Y, (E—E0) ZX), when Δχ> = Δγ, the arithmetic circuit 72 reads out each of the reached gradations Α, Β, and C from the LUT 35, and uses the following formula (1 As shown in

D2 (i, j, k) = Α + Δ χ · (Β-Α) + Δγ · (C-B) '' (1)

To calculate D2 (i, j, k). On the other hand, in the case of Δχ ΔAy, the modulation processing unit 34 reads each of the reached gradations A, J and D from the LUT 35, and, as shown in the following equation (2),

 D2 (i, j, k) = C + Δ χ (C-D) + (1-Δγ)-(D-A) '(2)

 To calculate D2 (i, j, k).

 [0049] For example, in the example of FIGS. 4 and 5, when (S, E) is (144, 48), (128, 32), (12 8, 64), (160, 64) and (160, The calculation area surrounded by 32) is specified, and the corrected video data D2 (i, j, k) force S60 is obtained.

 By the way, as described above, the LUT 35 according to the present embodiment basically has data indicating the second gradation corresponding to the combination of the first gradation and the third gradation. An exception is a combination of gradations that are stored but do not cause gradation transition (a combination in which the values of both video data D (i, j, k) -DOG.jk-l) are equal to each other). The LUT35 uses the interpolation calculation to calculate the video data D2 (i, j, k) in the correction range instead of the second gradation value (D (i, j, k) value itself) The value V that is larger than the value of the 2nd gradation is stored as the value that is set so that the error in minimizing the error is minimized. Furthermore, in the present embodiment, as a more preferable setting, the error is set to be the smallest in a range where there is no region in which correction is too strong in the correction range. In FIG. 6, for example, the value when the gradation indicated by the video data D (i, j, k) of the current frame FR (k) is 32 gradations is the value after V, such as V (32). A value indicating the value of the video data D (i, j, k) of the current frame FR (k) is attached.

 [0051] Further, the modulation processing unit 34 according to the present embodiment is a combination in which gradation transition does not occur in the value to be read from the LUT 35 in the case of decay gradation transition (DO = D If the value corresponding to the combination is included, instead of reading the value corresponding to the combination from the LUT35, the video data DO of the previous frame FR (kl) or the current frame FR (k) Can be interpolated using video data D. Note that the gradation transition is decay when the brightness decreases due to the gradation transition, and the video data D of the current frame FR (k) rather than the video data DO of the previous frame FR (kl). This is the case when is smaller.

[0052] In the following, referring to FIG. 6, the coordinates of (S, E) (0, 32), (0, 64) are defined as a small area having a point where gradation transition does not occur in one of the four corners. ), (32, 64) and (32, 32) as 4 corners The value stored in the LUT 35 will be described using the small area Al as an example.

[0053] Here, when only the video data D of the current frame FR (k) is changed from the coordinates (32, 32) to (32, 64), how the optimal video data D2 changes. When S—E is plotted on the horizontal axis and the optimal value of the video data D2 is plotted on the vertical axis, the characteristic C1 shown by the two-dot chain curve in FIG. 6 is obtained. Note that the optimum value of the video data D2 can be determined in the same manner as when determining other values of the LUT 35 described above (values when no gradation transition occurs).

On the other hand, as a first comparative example, the LUT 35 stores the video data D itself of the current frame FR (k) corresponding to the combination of gradations in which no gradation transition occurs, and the modulation processing unit In the configuration in which linear interpolation is always performed, the characteristic of the video data D2 is the characteristic C2 shown by the broken line in FIG.

 Furthermore, as a second comparative example, as in the modulation processing unit 34 according to the present embodiment, when the gradation transition amount (E−S) is less than the predetermined threshold L, the gradation transition In the configuration without emphasizing, the characteristic of the video data D2 output from the modulation processing unit is the characteristic C3 indicated by the solid line in FIG.

 [0056] However, in the configuration of the second comparative example, since the video data D itself of the current frame FR (k) is stored corresponding to the combination of gradations in which no gradation transition occurs, S— At a location where E is larger than the threshold value L, the output video data D2 has a value significantly lower than the ideal characteristic C1 described above.

 On the other hand, the LUT 35 according to the present embodiment stores a value larger than the video data D of the current frame FR (k) corresponding to the combination of gradations in which no gradation transition occurs. Yes. Therefore, the modulation processing unit 34 can output the video data D2 having the characteristic C4 shown by the solid broken line in FIG.

More specifically, the video data before correction is D (n—1) and D (n), and the corresponding video data after correction is D2 (n—1) and D2 (n). In this case, the broken line characteristic C4 is D2 (n) = D (n) when the gradation transition amount of the video data before correction is less than the threshold L, and the gradation transition amount is When it is larger than the threshold L, D2 (n) = a + k- [(D (n) -D (n-l)]. In the example of Fig. 6, D2 (n) = D2, D ( n) = D, D (n—1) = 32, so when the amount of gradation transition is larger than the threshold L, D2 = a + k- (D—32) Thus, when the gradation transition amount is less than the threshold value L, D2 = D.

[0059] Here, in this embodiment, since no gradation transition occurs, a value larger than the video data D of the current frame FR (k) is stored corresponding to the combination of gradations. Compared to the configuration of the second comparative example, the video data D2 after linear interpolation has a larger value. Therefore, the modulation processing unit 34 can output video data D2 that is closer to the ideal characteristic C1.

 [0060] In FIG. 6, the video data DO of the previous frame FR (k-1) is set to a certain value as an example.

 (Figure 6: 32 gradations) About the characteristics of the corrected video data D2 when only the video data D of the current frame FR (k) is increased by the same value as the video data DO As described below, as described below, in the case of rise gradation transition, the modulation processing unit 34 according to the present embodiment is closer to the ideal characteristic C1 than the configuration of the second comparative example. It is generally true that “the video data D2 can be output”. The case where the gradation transition is “rise” means that the luminance increases due to the gradation transition, and the video data D of the current frame FR (k) is more than the video data DO of the previous frame FR (kl). Is larger (more precisely, the luminance indicated by the video data D is greater than the luminance indicated by the video data DO).

 That is, the force with which the pixel array 2 according to the present embodiment is a liquid crystal display panel. Generally, the larger the gradation difference, the torque that must be applied to the liquid crystal molecules for response, or the liquid crystal molecules that are applied to the response. Increased torque. Therefore, as the moving distance increases, the observed response time becomes shorter. As a result, when the modulation processing unit 34 is configured to generate the video data D2 by linear interpolation, the correction becomes insufficient as the gradation difference becomes smaller, and the video data D2 generated by the interpolation with respect to the gradation transition amount The ratio of the difference from the ideal video data D2 value tends to increase.

[0062] In other words, when the gradation transition is rise, how the combination of the video data DO of the previous frame FR (kl) and the video data D of the current frame FR (k) is changed Similar to Fig. 6, even if the characteristic C1 of the ideal video data D2 with respect to the gradation transition amount (E-S) is drawn, the characteristic C1 is It becomes a convex curve. [0063] As a result, as in the second comparative example, gradation transition does not occur! When linear interpolation is performed so that the video data D itself of the current frame FR (k) can be output, When tone transition emphasis is required, only video data D2 smaller than the ideal value can always be output.

 [0064] On the other hand, if the modulation processing unit 34 according to the present embodiment outputs a linearly interpolated value even when gradation transition does not occur as described above, the modulation processing unit 34 of the current frame FR (k) Linear interpolation is performed so that a larger value than the video data D can be output. Therefore, the identification of the video data D2 output from the modulation processing unit 34 is as indicated by C4 in the figure, and the modulation processing unit 34 outputs video data D2 that is closer to the ideal characteristic C1. Can do.

 [0065] Here, the value V referred to when outputting the C4 is calculated as follows, for example. Specifically, when the point where the gradation transition amount is maximum is P1, and the point where the gradation transition amount is L is P2, P1 and P2 are connected by a straight line. The video data D2 at point P3 that intersects the straight line with S = 32 (the straight line where video data D is the minimum value) is V. More preferably, when selecting P2, it is desirable to select P2 within a range in which the correction amount in the correction interval does not exceed the ideal value (that is, it is not overcorrected).

 [0066] Since the linear interpolation by the modulation processing unit 34 is set as described above, assuming that the linearly interpolated value is output even when no gradation transition occurs, the video data A value larger than D is output. In this case, the brightness of the pixel PIX is controlled to the correct brightness (the brightness indicated by the video data D of the current frame FR (k)) when there is no gradation transition, such as when a still image is displayed. As a result, the display quality of the image display device 1 deteriorates.

 However, when the gradation transition amount (S−E) is smaller than the predetermined threshold L, the modulation processing unit 34 according to the present embodiment does not perform gradation transition enhancement and does not perform the current frame FR ( The video data D of k) is output. Therefore, even if the linear interpolation by the modulation processing unit 34 is set as described above, the image display apparatus 1 can control the luminance of the pixel PIX that has no problem at the time of still image display to the correct luminance. , Display quality can be prevented from deteriorating.

By the way, in the above, even in the case of the force decay gradation transition described by taking the case of the rise gradation transition as an example, the principle can be considered in the same manner as the different forces. That is, In the case of decay, the response is based on the relaxation of the elastic body, but the greater the gradation difference, the greater the torque that must be applied to the liquid crystal molecules for response, or the torque that is applied to the liquid crystal molecules during response. Therefore, the longer the moving distance, the faster the response speed of the liquid crystal molecules, and the response time can be further shortened when the correction amount is the same.

 [0069] Similarly, the greater the gradation difference, the greater the torque that must be applied to the liquid crystal molecules for response, or the torque that is applied to the liquid crystal molecules during response, and thus the moving distance increases. The shorter the observed response time.

 As a result, when the modulation processing unit 34 is configured to generate the video data D2 by linear interpolation, the correction is insufficient as the gradation difference becomes smaller, and the video generated by the interpolation with respect to the gradation transition amount is reduced. The ratio of the difference between the data D2 and the ideal video data D2 tends to increase.

 [0071] Therefore, when the gradation transition is decaying, changing the combination of the video data DO of the previous frame FR (k-1) and the video data D of the current frame FR (k) Similar to Fig. 6, even if the characteristic C1 of the ideal video data D2 is drawn with respect to the gradation transition amount (E-S), the characteristic C1 is below in the range where gradation transition emphasis is required. It becomes a convex curve.

 As a result, as in the second comparative example, gradation transition does not occur! In this case, if linear interpolation is performed so that the video data D itself of the current frame FR (k) can be output, When tone transition emphasis is required, only video data D2 larger than the ideal value can always be output.

 However, when the vertical alignment mode liquid crystal cell is used in the normally black mode as in the present embodiment, the response characteristic to the gradation transition in the decay direction is the response to the gradation transition in the rise direction. Compared with the characteristics, it is less affected by the level of the gradation transition amount, and the above-described insufficient correction does not occur much.

In addition, when the vertical alignment mode liquid crystal cell is used in a normally black mode, the response characteristic in the rise direction is particularly susceptible to the amount of gradation transition. Furthermore, especially at the time of gradation transition starting from the 0th gradation, the response is very slow, so a large amount of correction is required (the difference between the uncorrected video data D and the corrected video data D2 is large). [0075] Accordingly, the following configuration, that is, not only storing values for correcting the video data D at the time of gradation transition in the rise direction with high accuracy, but also image data D at the time of gradation transition in the decay direction. Compared with the configuration stored in the LUT 35, the circuit scale can be reduced without degrading the display quality much more than the value stored in the LUT 35.

 [Second Embodiment]

 In the present embodiment, a configuration for suppressing the above-mentioned correction insufficiency will be described with reference to FIG. 7 for gradation transition in the decay direction as well as gradation transition in the rise direction.

 That is, as shown in FIG. 1, the modulation drive processing unit 21a according to the present embodiment has substantially the same configuration as the modulation drive processing unit 21 according to the first embodiment, but the modulation processing unit 34 Instead of the LUT 35, a modulation processing unit 34a and a LUT 35a are provided.

 [0078] The LUT 35a has substantially the same force as the LUT 35 shown in FIG. 5. As shown in FIG. 7, no tone transition occurs, and the tone transition in the rise direction is emphasized corresponding to the combination. The value V2 for emphasizing the gradation transition in the decay direction, which is not just the value VI, is also stored. These values VI and V2 correspond to the first and second parameters described in the claims.

 Here, the decay direction value V2 is smaller than the video data D2 = DO = D. The value V2 is substantially the same as in the first embodiment.For example, when the point where the gradation transition amount is maximum is P1, and the point when the gradation transition amount force is P2, P1 and P2 And V is the video data D2 at point P3 when the current video data D is minimized. As with the rise method, when selecting P2, the error in the correction value is minimized in such a range that the correction amount in the correction interval does not exceed the ideal value (because it is a decay, it is less than the correction value). It is preferable to select such that

[0080] Further, the modulation processing unit 34a, when reading from the LUT 35a a value corresponding to a combination that is substantially the same as the modulation processing unit 34 and does not cause a power gradation transition, reads the video data of the current frame FR (k) Based on D and the video data DO of the previous frame FR (kl), it is determined whether the gradation transition is the rise direction or the decay direction, and if it is in the decay direction, it is stored in the LUT35a corresponding to the combination! Two values V 1 and V2 for decay direction Value V2 can be read. On the other hand, in the rise direction, the value VI for the rise direction can be read out of the both values VI and V2.

Here, the values VI and V2 may be stored as they are. However, in the present embodiment, in order to reduce the storage capacity, the values VI and V2 are stored in the current frame FR (k). Is stored in the form of a difference value with respect to the video data D (or video data DO of the previous frame FR (kl)), and the value Via or V2a read from the LUT 35 is added to the video data D (or DO). Or subtract to restore the pre-difference values VI and V2

[0082] With the above configuration, as described in the first embodiment, it is possible to suppress the above-described undercorrection for the gradation transition in the decay direction, which is not only possible to suppress the undercorrection at the time of the transition in the rise direction. Compared with the configuration of the second comparative example, it is possible to output larger video data D2 that is closer to the ideal characteristic C1.

 Note that in this embodiment as well, as in the first embodiment, when the gradation transition amount falls below the threshold L, the modulation processing unit 34a does not emphasize the gradation transition, so Display quality can be prevented from degrading.

 [Third Embodiment]

 In the present embodiment, a configuration capable of switching between the LUT 35 of the first embodiment and the LUT 35a of the second embodiment according to the situation will be described with reference to FIG. Note that there are various triggers for changing the value to be stored in the LUT (the degree of gradation transition emphasis), such as temperature and the type of image to be displayed (many motions, whether it is a video, etc.). In the following, we will explain the case of switching the LUT using temperature as a trigger.

 More specifically, when the rise direction value Via and the decay direction value V2a are stored in the LUT 35a as in the second embodiment, video data D2 closer to the ideal characteristic C1 is output. On the other hand, the range of Via and V 2a values that can be stored without increasing the storage capacity of the LUT 35a is limited.

[0086] For example, the video data DO and D are each represented by 8 bits, and the value corresponding to one combination of the video data DO and D is stored on the LUT 35a. When an 8-bit storage area is provided as an area, if both the values VIa and V2a are stored in the storage area, the size of the storage area that can be occupied by the values Via and V2a, respectively. For example, it is limited to 4 bits each. Therefore, the range of values that can be taken by the value VO stored in the LUT 35a corresponding to the combination that causes gradation transition is the range of values that can be expressed in 8 bits (0 to 255). The range of values Via and V2a is limited to the range of values (0 to 16) that can be expressed with 4 bits.

 Therefore, for example, when the correction amount is large (when the degree of gradation transition emphasis is large), such as when the temperature is relatively low, it is necessary to store an appropriate value in the LUT 35a. As the storage capacity increases, the circuit scale of the modulation drive processing unit also increases.

 On the other hand, the modulation drive processing unit according to the present embodiment increases the necessary storage capacity in the following cases, that is, when an appropriate value is stored in the LUT 35a having a large correction amount. In this case, the LUT 35 is used. In other cases, the LUT 35a can be used to output video data D2 closer to the ideal characteristic C1 without increasing the circuit scale.

 [0089] Specifically, the modulation drive processing unit according to this embodiment differs from the configuration in which the same LUT is used regardless of the temperature as in the first and second embodiments. Depending on which temperature range the current temperature belongs to, the modulation processing unit can switch the LUT that is referenced when emphasizing gradation transition.

More specifically, as shown in FIG. 8, the modulation drive processing unit 21 according to the present embodiment has a force substantially the same as that of the modulation drive processing unit 21 according to the first embodiment. Instead, a LUT group 37 consisting of LUTs corresponding to the above temperature ranges is provided. The plurality of LUTs constituting the LU T37 are LUT35 force or LUT35a. The number of LUTs 35 and 35a may be set to any one, but one of the LUTs is LUT35, and the other of the LUTs is LUT35a. In the present embodiment, the LUT 35 is made to correspond to the following temperature range T1, that is, the temperature range T2 in which the necessary storage capacity increases if an appropriate value is stored in the LUT 35a having a large correction amount. ,Excluding that The temperature range corresponds to LUT35a.

In addition, the modulation drive processing unit 21b according to the present embodiment is provided with a temperature sensor 36 that detects the temperature of the panel 11 shown in FIG. 2, in addition to the configuration of the modulation drive processing unit 21. The temperature sensor 36 may be arranged at any position as long as it can detect the temperature of the pixel PIX. However, it can detect the temperature of the pixel PIX more accurately even if it has an influence on the display. In order to estimate, it is preferable that the pixel electrode of the pixel PIX is provided and is provided on the non-display area among the substrate, the opposite substrate, or the color filter.

 [0092] Further, the modulation processing unit 34b provided in place of the modulation processing unit 34 is based on the detection result of the temperature sensor 36, and at the present time among the plurality of LUTs (35, 35a, ...). It is possible to select the LUT to be referred to during gradation transition enhancement and output the corrected video data D2 based on the value stored in the LUT.

 [0093] Further, in the case of the selected LUT force SLUT 35a, the modulation processing unit 34b operates in the same manner as the modulation processing unit 34a according to the second embodiment, and can output the video data D2. On the other hand, in the case of the selected LUT force LUT 35, the video data D2 can be output by operating in the same manner as the modulation processing unit 34 according to the first embodiment.

 [0094] In the above configuration, when the detection result force temperature range T1 of the temperature sensor 36 is indicated, the modulation processing unit 34b generates the corrected video data D2 with reference to the LUT 35. Unlike the case where all of the LUTs are LUT35a, the following temperature range, that is, a temperature range that increases the amount of correction and attempts to store an appropriate value in the LUT35a increases the required storage capacity. However, it is possible to suppress insufficient correction at the time of gradation transition in the rise direction without increasing the storage capacity required for the LUT. On the other hand, in this embodiment, since at least one of the LUTs is the LUT 35a, the video data D2 closer to the ideal characteristic C1 can be output compared to the case where all of the LUTs are the LUT 35a. As a result, it is possible to output video data D2, which is closer to the ideal characteristic C1, without increasing the circuit scale, and to improve the display quality.

In each of the above embodiments, the force described using the case where a liquid crystal cell of vertical alignment mode and normally black mode is used as a display element is not limited to this. In the case of a liquid crystal display device, in general, the larger the gradation difference, the greater the torque that must be applied to the liquid crystal molecules for response, or the torque that is applied to the liquid crystal molecules during response, and the greater the travel distance. The observed response time is shortened. Therefore, if the modulation processing unit generates the above video data by linear interpolation, the gradation difference will be small.Therefore, the correction will be insufficient, and the video data D2 generated by interpolation with respect to the gradation transition amount will be ideal. The ratio of difference from the value of typical video data D2 tends to increase. As a result, if it is a liquid crystal display device, the same effects as those of the above embodiments can be obtained.

[0096] Even if it is not a liquid crystal display device, the response speed of the pixels is relatively slow, so a large correction is required, and the force is also a correction value (the value of video data D before correction and the value after correction). If the display element has a large difference depending on the gradation transition amount, the same effect can be obtained.

 In the above embodiments, the force described by taking as an example the case where each member constituting the modulation drive processing unit is realized only by hardware is not limited to this. You may implement | achieve all or one part of each member with the combination of the program for implement | achieving the function mentioned above, and the hardware (computer) which performs the program. As an example, the computer connected to the image display device 1 may realize the modulation drive processing unit (21 to 21b) as a device driver used when driving the image display device 1. In addition, when a modulation drive processing unit is realized as a conversion board built in or externally attached to the image display device 1, and the operation of a circuit that realizes the modulation drive processing unit can be changed by rewriting a program such as firmware. For example, by distributing a recording medium on which the software is recorded or transmitting the software via a communication path, the software is distributed to the hardware and the software is executed. The hardware may be operated as the modulation drive processing unit in each of the above embodiments.

 [0098] In these cases, if hardware capable of executing the functions described above is prepared, the modulation drive processing unit according to each of the above embodiments is realized by causing the hardware to execute the program. it can.

[0099] In more detail, when implemented using software, a powerful computing means such as a CPU or hardware capable of executing the functions described above, such as ROM and RAM By executing the program code stored in the storage device and controlling peripheral circuits such as an input / output circuit (not shown), the modulation drive processing units 21 to 21b according to the above embodiments can be realized.

 [0100] In this case, it can also be realized by combining hardware that performs a part of the processing and the above-described arithmetic means that executes the program code for controlling the hardware and the remaining processing. Further, among the above-described members, even the members described as hardware, the hardware for performing a part of the processing, and the arithmetic means for executing the program code for controlling the hardware and the remaining processing It can also be realized by combining. The arithmetic means may be a single unit, or a plurality of arithmetic means connected via a nose inside the apparatus or various communication paths may execute the program code jointly.

 [0101] The program code itself that can be directly executed by the computing means, or a program as data that can generate the program code by a process such as unzipping described later, is stored in the recording medium. And the recording medium is distributed, or the program is transmitted by a communication means for transmitting via a wired or wireless communication path, and is executed by the arithmetic means. The

 [0102] In the case of transmission via a communication path, each transmission medium constituting the communication path propagates a signal sequence indicating a program, whereby the program is transmitted via the communication path. . Further, when transmitting the signal sequence, the transmission device may superimpose the signal sequence on the carrier by modulating the carrier with the signal sequence indicating the program. In this case, the signal sequence is restored by the receiving apparatus demodulating the carrier wave. On the other hand, when transmitting the signal sequence, the transmission device may divide the signal sequence as a digital data sequence and transmit it. In this case, the receiving apparatus concatenates the received packet groups and restores the signal sequence. Further, when transmitting a signal sequence, the transmission device may multiplex and transmit the signal sequence with another signal sequence by a method such as time division Z frequency division Z code division. In this case, the receiving apparatus extracts and restores individual signal sequences from the multiplexed signal sequence. In either case, the same effect can be obtained if the program can be transmitted via the communication channel.

Here, it is preferable that the recording medium when the program is distributed be removable, but it does not matter whether the recording medium after the program is distributed is removable. In addition, the above As long as the program is stored in the recording medium, it does not matter whether it is rewritable (writeable), volatile, recording method and shape. Examples of recording media include magnetic tapes, force set tapes, etc., floppy disks (registered trademark), magnetic disks, such as node disks, CD-ROMs, magneto-optical disks (MO), and mini disks (MD). And digital video disc (DVD) discs. The recording medium may be a card such as an IC card or an optical card, or a semiconductor memory such as a mask ROM, EPROM, EEPROM, or flash ROM. Alternatively, it may be a memory formed in a calculation means such as a CPU.

 [0104] The program code may be a code for instructing the arithmetic means of all procedures of the processes, or a part or all of the processes may be executed by calling according to a predetermined procedure. If a possible basic program (for example, operating system or library) already exists, replace all or part of the above procedure with code or pointers that instruct the arithmetic means to call the basic program. Anyway.

 [0105] Further, the format for storing the program in the recording medium may be a storage format that can be accessed and executed by the arithmetic means, for example, in a state where the program is stored in the real memory. From the storage format after installation on a local recording medium that is always accessible by the computing means (for example, real memory or a node disk) before being placed in the memory, or from a network or transportable recording medium. It may be the storage format before installing on a local recording medium. In addition, the program may be stored as source code that is not limited to the object code after con- taining, or as intermediate code generated during interpretation or compilation. In any case, the above calculation is performed by a process such as decompression of compressed information, decoding of encoded information, interpretation, compilation, linking, allocation to real memory, or a combination of processes. If the means can be converted into an executable format, the same effect can be obtained regardless of the format in which the program is stored in the recording medium.

[0106] As described above, the video data processing apparatus (for example, the signal processing units 21 '21a to 21b) according to any of the above-described embodiments shows the gradation of a certain pixel that is repeatedly input. Video data storage device that stores video data until next time (for example, frame memory 31 Etc.) and the above video data storage device power The gradation transition from the gradation indicated by the previous video data to the gradation indicated by the current video data is based on the read previous video data and the current video data. Correction means capable of outputting corrected video data corrected to be emphasized, and the correction means includes a predetermined part of a combination of values that can be taken by the previous and current video data. Corresponding to the combination, a parameter storage device (for example, LUT35'35a, etc.) that stores a parameter for determining the corrected video data corresponding to the combination, and both of the input video data The parameter force corresponding to the input combination that is a combination of the values of the two video data, and the difference between the gradations to be displayed exceeds a predetermined threshold value. If it is not stored, a plurality of parameters are read from the parameter storage device, parameters corresponding to the input combination are calculated by interpolation based on these parameters, and the corrected video data is generated. When the threshold value is not exceeded, an interpolation means (for example, the modulation processing units 34 ′ 34a to 34b etc.) that outputs the current video data without correction is provided, and the parameter storage device stores the above-described predetermined value. Among the combinations, the gradation indicated by the corrected video data determined by the parameter is a parameter corresponding to a specific combination in which the gradations indicated by the values constituting the combination are the same. In any of the gradations indicated by the values that make up a particular combination, Nagashi Kaji is also the level indicated by the values that make up the input combination. Difference in the mechanic have a feature that the parameters for calculating the parameters corresponding to the input combination by the interpolation operation when it exceeds the threshold value are stored.

 [0107] In the above configuration, when the difference between the gray levels indicated by the input video data exceeds a predetermined threshold value, the video data processing device corrects the corrected video in which the gray level transition is emphasized. Since the data can be output, the response speed of the pixel of the display device that displays the video data can be improved.

[0108] Further, since the interpolation means does not perform gradation transition emphasis when the amount of gradation transition does not exceed the threshold, the following problem, that is, when displaying a still image, For example, tones that slightly change due to noise or other effects are emphasized, Generation | occurrence | production of the malfunction that a transition will be visually recognized by the user can be prevented.

 [0109] Furthermore, the parameter storage device stores only the parameters corresponding to a part of the combinations of values that can be taken by the current and previous video data, and the parameters corresponding to the remaining combinations are interpolated. Therefore, the circuit size can be greatly reduced compared to storing parameters corresponding to all combinations in the parameter storage device.

 [0110] Further, in the parameter storage device, the following parameters, that is, the gradations indicated by the corrected video data determined by the parameters constitute the specific combination corresponding to the specific combination. In order to calculate the parameter corresponding to the input combination by the interpolation operation when the difference between the gradations indicated by the values constituting the input combination exceeds the threshold value in addition to any of the gradations indicated by the value. The parameters are stored. Therefore, corresponding to a specific combination in which no gradation transition occurs, it is caused by approximation using an interpolation operation as compared with a configuration in which the shift of the gradation indicated by the value constituting the specific combination is stored. The error can be reduced, and the display quality when displayed on the display device can be improved.

 [0111] As a result, it is possible to realize a display device that balances reduction in circuit scale and improvement in display quality at a higher level.

 [0112] When the parameters as described above are stored corresponding to the specific combination, if the interpolation calculation is used when the amount of gradation transition is equal to or less than the threshold value, the approximation using the interpolation calculation is used. There is a possibility that an error caused by the error becomes large. However, the interpolation means does not perform gradation transition enhancement when the amount of gradation transition does not exceed the threshold value. Therefore, when the amount of gradation transition is less than or equal to the threshold value, the error does not occur, and the deterioration in display quality due to the error can be prevented.

[0113] Further, in addition to the configuration described above, the parameter storage device may input the current input as a parameter corresponding to the specific combination rather than the first gradation indicated by the input previous video data. A first parameter when the second gradation indicated by the video data is brighter, and a second parameter when the second gradation is dark, and the interpolation means sends a parameter corresponding to the specific combination from the parameter storage device. When reading, the above first gradation If the second gradation is brighter, the first parameter may be read. If it is darker, the second parameter may be read.

 [0114] In this configuration, two parameters are stored corresponding to the above specific combination, so that the gradation transition in which the pixel brightness increases and the gradation transition in which the pixel brightness decreases In comparison with the following configuration, that is, the configuration storing the gradations indicated by the values constituting the specific combination corresponding to the specific combination in which the gradation transition does not occur! Errors due to approximation using interpolation operations can be reduced, and display quality can be improved.

 [0115] Further, in addition to the above configuration, each of the parameters indicates the gradation of the corrected video data, and the first and second parameters include the gradation indicated by the current video data and the parameters. When the first or second parameter is read out, the interpolation means reads the first or second parameter and the current video data and Based on the above, the parameter corresponding to the specific combination may be restored.

 [0116] In this configuration, each parameter indicates the gradation of the corrected video data, and the first and second parameters are stored as difference values. Here, when the first and second parameters are stored, that is, when a slight amount of gradation transition occurs and no color is generated, it is compared with the case where a larger amount of gradation transition occurs. Thus, the difference between the corrected video data and the previous and current video data is getting smaller. Therefore, by storing a parameter indicating the difference between the corrected video data and the previous or current video data, not the parameters indicating the corrected video data, the memory necessary for storing the first and second parameters is stored. The size of the area can be reduced. As a result, the circuit size of the video data processing apparatus can be reduced as compared with the case where the corrected video data itself is stored as the first and second parameters.

[0117] On the other hand, in the video data processing device according to the present invention, in addition to the above configuration, each of the parameters indicates the gradation of the video data after the correction. The parameter storage device includes the specific data As a parameter corresponding to the combination, the second gradation indicated by the inputted current video data is more than the first gradation indicated by the inputted previous video data. Only the parameters for the predetermined case between the brighter case and the darker case are stored, and the interpolation means obtains the parameter corresponding to the specific combination when the predetermined case is obtained. Is characterized in that the parameter storage device power parameter is read, and if not, the current video data is used as a parameter corresponding to the specific combination.

 [0118] In this configuration, if the second gradation indicated by the input current video data is brighter or darker than the predetermined one, the current video data is It is used as a parameter corresponding to the specific combination. Therefore, in both cases, the appropriate parameters are different from each other. When the other parameter is used as one parameter, the display quality is higher than when the value indicating the current video data is used as the parameter. Even when the image quality is reduced, the degree of display quality degradation corresponds to the following configuration, that is, the gray level indicated by the value constituting the specific combination corresponding to the specific combination in which no gray level transition occurs. Any of the above can be maintained in the same manner as the configuration for storing any of the above. As a result, it is possible to improve the display quality in the other while suppressing the deterioration of the display quality in one of the above cases.

In addition, the display device driving device (for example, the image display device 1 · la˜: Lb or the like) according to any one of the above-described embodiments has a pixel level repeatedly input as described above. Correcting means for correcting and outputting video data indicating a key (for example, signal processing units 21 · 21a to 21b) and outputting a signal corresponding to the corrected video data to the data signal line connected to the pixel A display device including output means (for example, the data signal line driving circuit 3), and the video data before correction, which has been repeatedly input, is defined as D (n-1) and D (n). Is D2 (n-1) and D2 (n), the above correction means allows the amount of gradation transition of the video data before correction to be greater than a predetermined threshold L. is greater, as the video data D2 (n) of the corrected, D2 a (n) = _a + k '[(D (n- 1) D ( n) ] When the gradation transition amount of the video data before correction does not reach the threshold value L, the correction means sets D2 (n) = D (n) as the corrected video data D2 (n). In addition to output, a is characterized in that it is set to a value different from D (n).

[0120] In this configuration, the gradation transition amount of the video data before correction is more than a predetermined threshold value. When it is large, D2 (n) = _a + k '[(D (n-1) 1 D (n)] is output as the corrected video data D2 (n), and the gradation of the video data before correction is output. When the transition amount is less than the threshold value L, D2 (n) = D (n) is output as the corrected video data D2 (n), and α is a value different from D (η). Is set to

[0121] Therefore, as with the video data processing apparatus, any of the following configurations, that is, gradation transition does not occur !, any of the gradations indicated by the values constituting the specific combination corresponding to the specific combination: Compared with a configuration that stores information, errors caused by approximation using interpolation calculation can be reduced, and display quality when displayed on a display device can be improved. As a result, it is possible to realize a display device that balances reduction in circuit scale and improvement in display quality at a higher level.

 Furthermore, the liquid crystal display device according to any of the above embodiments (for example, the image display device 1 · la˜: Lb, etc.) includes the video data processing device having the above-described configuration and the video data processing. It is characterized by having a liquid crystal display panel (for example, panel 11 etc.) driven by video data after correcting the device power. Therefore, similar to the above video data processing apparatus, the display quality can be improved without increasing the circuit scale so much, and the liquid crystal display that balances the reduction of the circuit scale and the improvement of the display quality at a higher level. An apparatus can be realized.

 [0123] In addition to the above configuration, the liquid crystal display device may be a television broadcast receiver or a liquid crystal monitor device. As described above, the liquid crystal display device having the video data processing device can balance the reduction in circuit scale and the improvement in display quality at a higher level. Therefore, it can be suitably used as a television broadcast receiver or a liquid crystal monitor device.

 Incidentally, the video data processing device may be realized by hardware! /, Or may be realized by causing a computer to execute a program. Specifically, a program according to the present invention is a program that causes a computer having each storage device that constitutes one of the above video data processing devices to operate as each means that constitutes the video data processing device. The program is recorded on the recording medium according to the present invention.

[0125] When these programs are executed by a computer, the computer Operates as a video data processing device. Therefore, similar to the above video data processing device, the display quality can be improved without significantly increasing the circuit scale, and a display device that balances the reduction of the circuit scale and the improvement of the display quality at a higher level. It can be realized.

 It should be noted that the specific embodiments or examples made in the detailed description of the invention are merely to clarify the technical contents of the present invention, and are limited to such specific examples. Accordingly, various modifications may be made within the spirit of the present invention and the scope of the following claims, which should not be interpreted in a narrow sense. Industrial applicability

[0127] According to the present invention, it is possible to reduce errors caused by approximation using interpolation calculation in the case where there is almost no gradation transition without excessively increasing the circuit scale, so that the circuit scale can be reduced and the display quality can be reduced. A display device in which improvement is balanced at a higher level can be realized. Therefore, for example, it can be widely used as a video data processing device for various display devices including a video data processing device provided in a liquid crystal television receiver or a liquid crystal monitor device.

Claims

The scope of the claims

 [1] A video data storage device that repeatedly stores video data indicating the gradation of a certain pixel until the next time;

 Based on the previous video data read from the video data storage device and the current video data, the gradation transition from the gray level indicated by the previous video data to the gray level indicated by the current video data is emphasized. Correction means capable of outputting corrected video data after correction, and

 The correction means has a parameter for determining corrected video data corresponding to a predetermined combination among the combinations of values that the previous and current video data can take. The difference between the gradations indicated by the stored parameter storage device and the input video data above both exceeds a predetermined threshold, and the force also corresponds to the input combination that is a combination of the values of both video data. If the parameter to be processed is not stored in the parameter storage device, a plurality of parameters are read from the parameter storage device, and the parameter corresponding to the input combination is calculated by interpolation based on these parameters. If the above corrected video data is generated and the threshold is not exceeded, the current video data is And a interpolating means for outputting without Tadase,

 In the parameter storage device, a parameter corresponding to a specific combination in which the gradations indicated by the values constituting the combination are the same among the predetermined combinations is determined by the parameter. The gradation indicated by the corrected video data is not the difference between the gradations indicated by the values constituting the specific combination, and the difference between the gradations indicated by the values constituting the input combination exceeds the threshold value. A video data processing apparatus, wherein a parameter for calculating a parameter corresponding to the input combination is stored by the interpolation operation when the number exceeds.

[2] The parameter storage device, as a parameter corresponding to the specific combination, has a second level indicated by the input current video data rather than the first gray level indicated by the input previous video data. With a first parameter when the key is brighter and a second parameter when the key is darker. When the interpolation means reads out the parameter corresponding to the specific combination from the parameter storage device, it reads out the first meter when the second gradation is brighter than the first gradation, and reads out the parameter when dark. 2. The video data processing apparatus according to claim 1, wherein the second parameter is read out.

 [3] Each parameter indicates the gradation of the corrected video data, and the first and second parameters indicate the gradation indicated by the current video data and the corrected video data as the parameter. It shows the difference from the gradation,

 When the first or second parameter is read, the interpolation means restores the parameter corresponding to the specific combination based on the first or second parameter and the current video data. The video data processing apparatus according to claim 2.

 [4] Each parameter indicates the gradation of the corrected video data.

 In the parameter storage device, as a parameter corresponding to the specific combination, the second gradation indicated by the inputted current video data is more than the first gradation indicated by the inputted previous video data. Only the preset parameters are stored between when the light is bright and dark,

 When obtaining the parameters corresponding to the specific combination, the interpolation means reads the parameter storage device power parameter if it is determined in advance, and if not, identifies the video data of this time in the specific case. The video data processing apparatus according to claim 1, wherein the video data processing apparatus is used as a parameter corresponding to a combination of the two.

 [5] correction means for correcting and outputting video data indicating the gradation of a certain pixel that is repeatedly input;

 An output means for outputting a signal corresponding to the corrected video data to a data signal line connected to the pixel;

 When the video data before correction that is repeatedly input is D (n— 1), D (n) and the corresponding video data after correction is D 2 (n— 1), D 2 (n) ,

 The correction means, when the gradation transition amount of the video data before correction is larger than a predetermined threshold, when the corrected video data D2 (n),

D2 (n) = a + k '[(D (n) — D (n— 1)] When the gradation transition amount of the video data before correction is less than the threshold value L, the correction means, as the corrected video data D2 (n),

 D2 (n) = D (n) is output and

 (X is set to a value different from D (n), and the display device driving device is characterized in that:

 [6] A correction process for correcting and outputting video data indicating the gradation of a certain pixel that has been repeatedly input,

 An output step of outputting a signal corresponding to the corrected video data to a data signal line connected to the pixel,

 When the video data before correction that is repeatedly input is D (n— 1), D (n) and the corresponding video data after correction is D 2 (n— 1), D 2 (n) ,

 When the video data D2 (n) after correction in the correction step is larger than the predetermined threshold L, the gradation transition amount of the video data before correction is

 D2 (n) = a + k. [(D (n) — D (n— 1)],

 When the gradation transition amount of the video data before correction is less than the above threshold L,

 D2 (n) = D (n)

 The above-mentioned oc is set to a value different from D (n), and the display device driving method is characterized in that:

 [7] The video data processing device according to any one of claims 1 to 5,

 A liquid crystal display device comprising: a liquid crystal display panel driven by the video data after the correction of the video data processing device power.

8. The liquid crystal display device according to claim 7, wherein the liquid crystal display device is a liquid crystal television receiver or a liquid crystal monitor device.

[9] A computer having each storage device according to any one of claims 1 to 5.

, A program to be operated as each means described in the claim.

[10] A computer-readable recording medium on which the program according to claim 9 is recorded.