JP2010146015A - Animation processing device, animation processing method and animation processing program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an animation processing method improving the subjective image quality of animation displayed on a liquid crystal display. <P>SOLUTION: This animation processing method for processing animation displayed on the liquid crystal display includes: an output value deciding step of deciding an output value in outputting an image of a predetermined position of a second frame according to a pixel value in a predetermined position in a first frame contained in animation, a pixel value at a position corresponding to the predetermined position in the second frame and the degree of response delay caused when the liquid crystal display displays animation; an edge area detecting step of detecting an edge area from the second frame; and an output value correction step of correcting the output value to the edge area so that an absolute value of an output differential value between an output value decided in the output value deciding step to the edge area and an output value output now becomes larger by a first predetermined correction amount. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a moving image processing apparatus, a moving image processing method, and a moving image processing program for processing a moving image to be displayed on a liquid crystal display device.

  In recent years, liquid crystal displays have become widespread over a wide range of fields such as PC (personal computer) monitors, notebook PCs, and televisions. Along with this, the chances of watching moving images on a liquid crystal display have increased greatly.

  However, since the response speed of the liquid crystal display is not sufficiently high, image quality degradation such as blurring and afterimages occurs when a moving image is displayed. Generally, the refresh rate of a liquid crystal display is 60 Hz. Therefore, a response speed of 16.7 ms or less is targeted in order to support moving image display.

  In recent liquid crystal displays, the response speed of binary (0 to 255 gradations or 255 to 0 gradations in a 256 gradation display liquid crystal display) is 16.7 ms or less. However, the response speed between halftones is 16.7 ms or more.

  Since a general moving image includes a large number of responses between halftones, the problem that the response speed between halftones is not sufficient causes deterioration in the image quality of the moving images. That is, further improvement in response speed is necessary.

  In order to increase the response speed of a liquid crystal display, development of a new liquid crystal material having a high response speed, improvement of a driving method of a liquid crystal display using a conventional liquid crystal material, and the like have been performed. Examples of new liquid crystal materials include smectic ferroelectric liquid crystals and antiferroelectric liquid crystals.

  However, there are many problems to be solved, such as a problem of image sticking due to the influence of spontaneous polarization of the liquid crystal material and a tendency for the alignment state of the liquid crystal to be broken by pressure or the like.

  On the other hand, a technique for improving the response speed of a liquid crystal display has been developed by improving a driving method of a liquid crystal display using a conventional liquid crystal material. For example, a method of writing in a liquid crystal display a gradation obtained by adding a predetermined gradation to the writing gradation when the gradation displayed on the liquid crystal display changes (see, for example, “Non-Patent Document 1”). )

  On the other hand, there is edge enhancement as a method for improving the sharpness in the spatial direction of an image. Edge enhancement is a technique for improving the sharpness of an image by enhancing the differentiation in the spatial direction of the image (generally, since the image is discontinuous data, the difference in pixel values between adjacent pixels). .

2001 SID International Symposium Digest of Technical Papers / Volume XXXII / ISSN-0001-966X 488

  However, edge enhancement generally improves the sharpness of an image from information only in the spatial direction of the image. Therefore, the edge enhancement effect is insufficient for moving images. That is, when the observer gazes at the moving object region of the moving image, the gazing point moves unlike the still image, and the apparent contrast for the observer decreases.

  In a general imaging system, imaging is performed by integrating light input for a certain period. For this reason, in a moving body, the position shifted spatially will be integrated. Thereby, so-called imaging blur occurs, and the contrast of the moving object is lower than that of the still image.

  Further, in a liquid crystal display device, since a moving image is continuously displayed as a still image for one frame period, a phenomenon called so-called hold blur appears, and the contrast of a moving object is lowered.

  As described above, in general edge enhancement, when a still region and a moving object region exist in a moving image, the apparent sharpness of the still region and the moving object region is different. As a result, there is a problem that the effect of improving the subjective image quality is small.

  The present invention has been made in view of the above problems, and provides a moving image processing method for improving the subjective image quality of a moving image displayed on a liquid crystal display device.

  In order to solve the above-described problem, a moving image processing device according to an aspect of the present invention is a moving image processing device that processes a moving image to be displayed on a liquid crystal display device, and includes a first frame included in the moving image. The liquid crystal display with reference to a pixel value at a predetermined position and a pixel value at a position corresponding to the predetermined position in a second frame continuously arranged in the time axis direction with the first frame Output value determining means for determining an output value of a pixel at the predetermined position in the second frame based on a degree of response delay caused when the apparatus displays a moving image; and an edge region from the second frame. The edge region detection means for detecting, and the output so that the absolute value of the difference between the output value for the detected edge region and the pixel value at the predetermined position in the second frame is larger. Complement value And an output value correcting means for.

  ADVANTAGE OF THE INVENTION According to this invention, the image quality of the moving image displayed on a liquid crystal display device can be improved.

2 is a block diagram showing a functional configuration of the moving image processing apparatus 10. FIG. The figure which shows typically the relationship between the gradation L0 in a 1st frame, the gradation L1 in a 2nd frame, and the initial emphasis gradation Le. The figure which shows typically the data structure of LUT of the array data holding | maintenance part 106. FIG. The figure which shows the relationship between the edge intensity | strength I of the edge area | region detected by the edge detection part 102, and emphasis correction coefficient (beta). The figure which shows the other example of the relationship between edge intensity | strength I of the edge area | region detected by the edge detection part 102, and emphasis correction coefficient (beta). The figure which shows the other example of the relationship between edge intensity | strength I of the edge area | region detected by the edge detection part 102, and emphasis correction coefficient (beta). The figure which shows the other example of the relationship between edge intensity | strength I of the edge area | region detected by the edge detection part 102, and emphasis correction coefficient (beta). The figure which shows the N flame | frame 210. FIG. The figure which shows the N + 1 flame | frame 220. The figure which shows the edge detection image 230 obtained when the edge detection part 102 detected the edge area | region from the N + 1 frame. The figure showing the absolute value difference of N frame 220 and N + 1 frame 230. Edge region with motion obtained by AND operation of a value obtained by binarizing the edge detection image 230 of the N + 1 frame shown in FIG. 9 and a value obtained by binarizing the absolute value difference between the N frame 220 and the N + 1 frame 230 FIG. 3 is a flowchart showing moving image processing in the moving image processing apparatus 10 according to the first embodiment; 1 is a diagram illustrating a hardware configuration of a moving image processing apparatus 10 according to a first embodiment. FIG. 3 is a block diagram showing a functional configuration of a moving image processing apparatus 10 according to the second embodiment. The figure which shows the approximate straight line calculated | required from the least square error method by plotting each value by setting a horizontal axis as L1-L0 and a vertical axis | shaft as Le-L0. The block diagram which shows the function structure of the moving image processing apparatus 10 when the input video information is red, green, and blue three primary colors are figure information. The figure which shows the relationship between the frame rate of an input image, and the refresh rate of the liquid crystal display device 20. FIG. 10 is a flowchart showing moving image processing by the moving image processing apparatus 10 according to the fifth embodiment;

  Hereinafter, embodiments of a moving image processing method, a moving image processing apparatus, and a moving image processing program according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a block diagram showing a functional configuration of a moving image processing apparatus 10 that performs a moving image processing method according to the present invention. The moving image processing apparatus 10 includes a frame memory 100, an edge detection unit 102, a gate array 104, and an array data holding unit 106. When video information is displayed on the liquid crystal display device 20, the video is degraded due to a response delay. In order to improve this, it is necessary to emphasize the change in gradation. The moving image processing apparatus 10 determines an enhanced gradation that is an enhanced gradation value to be output to the liquid crystal display device 20.

  The input video information is sent to the frame memory 100, the edge detector 102, and the gate array 104. The frame memory 100 holds the input video information for one frame period, and outputs the video information delayed by one frame period. In order to determine the emphasis gradation of the video information when displaying the video information on the liquid crystal display device 20, it is necessary to refer to the gradation of the input frame and the frame immediately before the frame. Hereinafter, the case where the first frame is held in the frame memory 100 and the second frame following the first frame is input from the outside will be described for convenience of description.

  The edge detection unit 102 detects an edge from the second frame. Then, it is sent to the gate array 104 as an edge detection image. Various methods can be considered as the edge detection method. In the present embodiment, the Sobel differential operator is used.

ここで、Ｉ（ｘ，ｙ）は座標（ｘ，ｙ）位置におけるエッジ強度を示している。Ｅ_x（ｘ，ｙ）は座標（ｘ，ｙ）位置の画素Ｐ_x（ｘ，ｙ）の水平方向の濃度勾配を示している。Ｅ_y（ｘ，ｙ）は座標（ｘ，ｙ）位置の画素Ｐ_y（ｘ，ｙ）の垂直方向の濃度勾配を示している。Ｈ_x、Ｈ_yはそれぞれ、水平方向、垂直方向の微分オペレータである。記号＊は、畳み込み演算を表している。Ｉ（ｘ，ｙ）は、２５５（８ビット）以上の値を持つことがあるが、飽和演算により２５５以下に丸め込んでいる。 Edge detection methods using the Sobel differential operator are shown in (Expression 1) to (Expression 3).

Here, I (x, y) indicates the edge strength at the coordinate (x, y) position. E _x (x, y) indicates the density gradient in the horizontal direction of the pixel P _x (x, y) at the coordinate (x, y) position. E _y (x, y) indicates the density gradient in the vertical direction of the pixel P _y (x, y) at the coordinate (x, y) position. H _x and H _y are differential operators in the horizontal and vertical directions, respectively. The symbol * represents a convolution operation. I (x, y) may have a value of 255 (8 bits) or more, but is rounded to 255 or less by a saturation operation.

  In this embodiment, edge detection using the Sobel differential operator is performed. However, in order to further reduce the processing load, for example, a method of obtaining only the horizontal differential may be used. In the case of a general captured moving image, the moving image has a lot of movement in the horizontal direction, and a sufficient effect can be obtained only by edge detection of the horizontal method.

  In the present embodiment, the edge detection image is obtained for each of the input gradations of red, green, and blue. As another example, the luminance components of red, green, and blue may be obtained, and the edge detection image for only the luminance component may be obtained. In addition, when the input video information is video information including luminance information and color difference information (Y, U, V, etc.) as in the decoding result of a moving picture experts group (MPEG2) video, the luminance information (Y) An edge detection image may be obtained.

  The array data holding unit 106 holds initial emphasized gradation data as a Look-Up Table (LUT). Here, the initial enhancement gradation data will be described with reference to FIG.

It is assumed that the gradation is converted from L ₀ to L ₁ in the first frame to the second frame. In this case, even if the gradation L ₁ is written to display the second frame on the liquid crystal display device 20, the target arrival floor is reached after one frame period (generally 1/60 seconds) due to the response delay of the liquid crystal display device 20. Key L ₁ cannot be reached.

Therefore, the writing the highlighted L _e instead of L _1. As a result, L ₁ can be reached after one frame period. This _Le is the initial emphasis gradation. 2, a gradation L ₀ in the first frame, the gray level L ₁ in the second frame, shows the relationship between the initial emphasis gradation L _e schematically. By writing a gradation larger than the gradation L ₁ , the gradation L ₁ can be reached after one frame period. The tone at this time is L _e.

The initial emphasis gradation L _e according to the embodiment corresponds to the output value determined in the output value determining step described in the claims. _{Further, L 1 -L 0, L e} -L 1 and L _e -L ₀ according to the embodiment, the first difference value according to the range of each claims, the second difference value, corresponding to the third difference value To do.

In this manner, by writing the initial emphasis gradation _Le that can reach L ₁ after one frame period into the liquid crystal display device 20, the target L ₁ can be reached after one frame period. That is, the response speed of the liquid crystal display device 20 can be apparently improved.

In sequence data holding unit 106 holds the initial emphasis gradation L _e in previously obtained entire gradation between, or responses between some gradations. FIG. 3 schematically shows the data structure of the LUT of the array data holding unit 106. The LUT is provided in a two-dimensional matrix with the horizontal axis L ₀ and the vertical axis L ₁ . In the cell corresponding to the position where the L ₀ column and the L ₁ row intersect, the corresponding _Le is arranged.

The method for holding gradation L _e is not limited to this embodiment, as an input gradation L ₀ and gradation L _1, may be any method capable of specifying a gradation L _e . For example, it may be held one-dimensionally.

Further, LUT does not need to hold a grayscale L _e between all gradations, for example 4 gradation L ₀ for each tone, even holds only gradation L _e for gradation L ₁ Good. In this case, the gradation L _e for gradation L _0, gradation L ₁ is not held in the LUT may be determined by linear interpolation or the like. Thereby, the LUT can be reduced. Therefore, the memory capacity can be reduced.

Further, LUT shown in FIG. 3, but retains the initial emphasis gradation L _e, the gradation L _e and gradation L ₁ of the difference, i.e., it may hold only enhancement amount. In this case, in a gate array 104 to be described later, a configuration for obtaining the gradation L _e by adding the gradation L ₁ enhancement amount held in the LUT.

  The array data holding unit 106 may be anything such as a ROM (Read Only Memory) and a RAM (Random Access Memory) as long as it can hold data.

The gate array 104 acquires the second frame from the outside and acquires the first frame from the frame memory 100. The gate array 104, a gradation L ₀ of the first frame acquired, as the address information and gradation L ₁ of the second frame, to obtain the initial enhancement gradation L _e corresponding the sequence data holding section 106.

As described above, the gate array 104 includes the LUT of the array data holding unit 106 created based on the pixel value at a predetermined position in the first frame, the pixel value at the corresponding position in the large two frames, and the degree of response delay. based on, it is possible to determine the initial emphasis gradation L _e.

The gate array 104 further acquires an edge detection image of the second frame from the edge detection unit 102. Based on the edge intensity of the edge detection image, the initial emphasis gradation L _e, by further performing a predetermined amount of enhancement processing, to produce an enhanced gradation actually written to the liquid crystal display device 20. Specifically, an edge emphasis process for further emphasizing the gradation of an edge region that changes between frames, that is, an edge region of a moving object is performed. Then, it is output as emphasized video information together with a timing signal (clock, horizontal synchronizing signal, vertical synchronizing signal, etc.) of the liquid crystal display device 20.

なお、実施の形態にかかる強調補正係数βは、特許請求の範囲に記載の第１強調補正係数に相当する。 Next, edge enhancement processing performed by the gate array 104 on the edge detection image will be described. Assuming that the enhancement correction coefficient based on the edge intensity of the edge detection image is β and the enhancement gradation to be finally written to the liquid crystal display device 20 is L _c , L _c is obtained by the following (Equation 4).

The enhancement correction coefficient β according to the embodiment corresponds to the first enhancement correction coefficient described in the claims.

ここで、β_maxは、エッジ強度が最大の時の最大強調補正係数である。β_maxは、利用者が任意に決定することができる。図４においては、エッジ強度の最大値を２５５とする。エッジ強度Ｉは、入力映像の画像のエッジ強度を８ビットの情報として（式１）から（式３）により求めた値である。このように、強調補正係数βは、エッジ強度に比例する値である。 Next, how to obtain the enhancement correction coefficient β will be described. FIG. 4 shows the relationship between the edge intensity I of the edge region detected by the edge detection unit 102 and the enhancement correction coefficient β. In the present embodiment, as shown in FIG. 4, the relationship is such that the enhancement correction coefficient β increases in direct proportion to the edge intensity I. Therefore, the correction coefficient β for the edge intensity I can be obtained by the following (Equation 5).

Here, β _max is a maximum enhancement correction coefficient when the edge strength is maximum. β _max can be arbitrarily determined by the user. In FIG. 4, the maximum edge strength is 255. The edge strength I is a value obtained from (Equation 1) to (Equation 3) as the 8-bit information of the edge strength of the input video image. Thus, the enhancement correction coefficient β is a value proportional to the edge strength.

ここで、Ｉ_Lthは、強調補正係数を増加させるエッジ強度の閾値である。なお、実施の形態にかかるＩ_Lthは、特許請求の範囲に記載の第１エッジ強度閾値に相当する。 In the present embodiment, the enhancement correction coefficient β is determined from the relationship shown in FIG. 4, but may be determined from another relationship. FIG. 5 shows the relationship between the enhancement correction coefficient β and the edge strength I according to such another example. As shown in FIG. 5, when the edge intensity I is small, the enhancement correction coefficient is set to 1. That is, it does not overemphasize. In this case, the enhancement correction coefficient β can be obtained by (Equation 6).

Here, I _Lth is a threshold value of edge strength for increasing the enhancement correction coefficient. Note that I _{Lth according to} the embodiment corresponds to the first edge intensity threshold value described in the claims.

  By determining the emphasis correction coefficient β from the relationship between the edge intensity I and the emphasis correction coefficient β shown in FIG. 5, it is possible to prevent overemphasis of a small change such as noise. As a result, noise can be emphasized and image quality can be prevented from deteriorating.

ここで、Ｉ_Hthは、強調補正係数を一定とするエッジ強度の閾値である。なお、実施の形態にかかるＩ_Hthは、特許請求の範囲に記載の第２エッジ強調閾値に相当する。 FIG. 6 shows the relationship between the enhancement correction coefficient β and the edge strength I according to another example. As shown in FIG. 6, when the edge strength is large, the enhancement correction coefficient is set to a constant value, that is, β _max . In this case, the enhancement correction coefficient β can be obtained by (Equation 7).

Here, I _Hth is a threshold value of edge strength that makes the enhancement correction coefficient constant. Note that I _{Hth according to} the embodiment corresponds to the second edge enhancement threshold value described in the claims.

  By determining the enhancement correction coefficient β from the relationship between the edge intensity I and the enhancement correction coefficient β shown in FIG. 6, it is possible to prevent excessive overemphasis when the edge intensity I is large.

As yet another example, the relationship between (Expression 6) and (Expression 7) may be combined. FIG. 7 shows the relationship between the enhancement correction coefficient β and the edge strength I in this case. In this case, the enhancement correction coefficient β can be obtained by (Equation 8).

  Next, the case where the moving image processing apparatus 10 performs processing on the N frame 210 shown in FIG. 8A and the N + 1 frame 220 shown in FIG. 8B will be specifically described. The N frame 210 includes a quadrangular object 211 and round objects 212, 213, 214, and 215 as shown in FIG. As illustrated in FIG. 8B, the N + 1 frame 220 includes a rectangular object 221 and round objects 222, 223, 224, and 225, as with the N frame 210. The square objects 211 and 221 are moving objects, and move from the N frame 210 to the N + 1 frame 220 in the horizontal direction of the frame. The round objects 212 to 215 and 222 to 225 are stationary.

  FIG. 9 shows an edge detection image 230 obtained by the edge detection unit 102 detecting an edge region from N + 1 frames. The edge detection unit 102 detects the edge of the entire input frame. Therefore, the edge detection image 230 includes edge regions 232, 233, 234, and 235 for the stationary circular objects 222 to 224 and an edge region 231 for the quadrilateral object 221.

  FIG. 10 shows an absolute value difference between the N frame 220 and the N + 1 frame 230. The rectangular objects 211 and 221 move from the left to the right in the horizontal direction of the frame from the N frame 220 to the N + 1 frame 230. Therefore, differences 241 and 242 between the background and the moving object are generated on the left and right sides of the rectangular objects 211 and 221.

In the present embodiment, the gate array 104 performs an enhancement process represented by (Expression 4) on the edge region detected by the edge detection unit 102. However, in (Equation 4), for L _e and L ₁ such that L _e −L ₁ = 0, L _c = L ₁ regardless of the enhancement correction coefficient β. That is, the enhancement process is not performed.

As shown in FIG. 10, since the round objects 222 to 225 in the N + 1 frame 220 are stationary, no inter-frame difference occurs. That is, in the round object 222 to 225, the L _e = L _1. That is, L _e −L ₁ = 0. Therefore, the enhancement processing is not performed on the round objects 222 to 225.

  In other words, the gate array 104 performs enhancement processing only on the edge region with motion among the edge regions detected by the edge detection unit 102. An area to which the gate array 104 performs enhancement processing, that is, an edge area with motion, is obtained by binarizing the edge detection image 230 of the N + 1 frame shown in FIG. 9 and the absolute value difference between the N frame 220 and the N + 1 frame 230 by 2. It is expressed as a logical product with the digitized value. FIG. 11 shows the motion obtained by the logical product operation of the value obtained by binarizing the edge detection image 230 of the N + 1 frame shown in FIG. 9 and the value obtained by binarizing the absolute value difference between the N frame 220 and the N + 1 frame 230. Edge regions 251 and 252 accompanied by are shown. The edge regions 251 and 252 are edge regions that change between frames of a square object that is a moving object in N + 1 frames.

  As described above, in the present embodiment, only the edge region with movement can be further emphasized, so that the sharpness of the moving image displayed on the liquid crystal display device 20 can be improved. Thereby, a high-quality moving image can be presented to the observer.

The gate array 104 according to the present embodiment executes the output value determination step, the correction amount determination step, and the output value correction step described in the claims. Here, the output value determined in the output value determination step corresponds to the initial enhancement gradation L _e , and the output value corrected in the output value correction step corresponds to the enhancement gradation L _c . In addition, the gate array 104 in this embodiment executes three steps according to an arithmetic expression.

FIG. 12 is a flowchart of the moving image processing in the moving image processing apparatus 10 according to the first embodiment. First, the gate array 104 determines the initial emphasis gradation L _e (step S100). Next, the edge detection unit 102 detects an edge region (step S102). When the edge region is detected (step S104, Yes), the gate array 104 detects the edge strength in the edge region (step S106). Next, the enhancement correction coefficient β is determined based on the detected edge intensity, and the enhancement gradation L _c is determined by (Equation 4) (step S108). Then, an image is output with the determined enhancement gradation L _c (step S110).

On the other hand, in step S104, if the edge area is not detected (step S104, No), and outputs the image by initial enhancement gradation L _e (step S110).

  FIG. 13 is a diagram illustrating a hardware configuration of the moving image processing apparatus 10 according to the first embodiment. The moving image processing apparatus 10 has, as a hardware configuration, a ROM 52 that stores a moving image processing program for executing moving image processing in the moving image processing apparatus 10, a CPU 51 that controls each unit of the moving image processing apparatus 10 according to a program in the ROM 52, A RAM 53 that stores various data necessary for controlling the moving image processing apparatus 10, a communication I / F 57 that communicates by connecting to a network, and a bus 62 that connects each unit are provided.

  The moving image processing program in the moving image processing apparatus 10 described above is a file in an installable or executable format and is a computer-readable recording medium such as a CD-ROM, a floppy (registered trademark) disk (FD), or a DVD. May be recorded and provided.

  In this case, the moving image processing program is loaded onto the main storage device by being read from the recording medium and executed by the moving image processing device 10 so that each unit described in the software configuration is generated on the main storage device. It has become.

  Further, the moving image processing program of the present embodiment may be provided by being stored on a computer connected to a network such as the Internet and downloaded via the network.

(Embodiment 2)
Next, the moving image processing apparatus 10 according to the second embodiment will be described. The moving image processing apparatus 10 according to the second embodiment displays video information on the liquid crystal display device 20 using a display method disclosed in Japanese Patent Laid-Open No. 2003-264846.

  FIG. 14 is a block diagram of a functional configuration of the moving image processing apparatus 10 according to the second embodiment. The moving image processing apparatus 10 according to the second embodiment includes a frame memory 100, an edge detection unit 102, an enhancement coefficient multiplication unit 110, and a gradation information conversion unit 112.

  The input video information input to the moving image processing apparatus 10 is input to the frame memory 100, the edge detection unit 102, and the enhancement coefficient multiplication unit 110. Here, the input video information includes luminance information (Y) and color difference information (U, V).

  The enhancement coefficient multiplication unit 110 includes an enhancement coefficient that is set in advance based on the response delay of the liquid crystal display device 20, an enhancement correction coefficient that is determined based on the edge intensity of the edge detection image detected by the edge detection unit 102, and luminance. The emphasized video information to be displayed on the liquid crystal display device 20 is calculated from the inter-frame difference value of the information and the color difference information. Specifically, the enhancement correction coefficient is multiplied by the difference value between frames of the luminance information and the color difference information. Further, the luminance information and the color difference information of the frame delayed by one frame period by the frame memory 100, that is, the first frame, are added to the obtained value. The video information thus obtained is output to the gradation information conversion unit 112 as emphasized video information.

The enhancement coefficient multiplication unit 110 obtains enhanced video information using (Equation 9).

Here, (Y ₀ , U ₀ , V ₀ ) indicates input video information, that is, luminance information and color difference information of the first frame. (Y ₁ , U ₁ , V ₁ ) indicates video information delayed by one frame, that is, luminance information and color difference information of the second frame. (Y _c , U _c , V _c ) indicates enhanced luminance information and color difference information of the second frame. α is an enhancement coefficient. β is an enhancement correction coefficient. β is a real number of 1 or more.

Emphasis coefficient α, the first frame gradation L ₀ as described with reference to FIG. 2 in the first embodiment, is determined by the relationship between the gradation L ₁ and the initial emphasis gradation L _e of the second frame. Specifically, it is determined by the least square error method. As shown in FIG. 15, plotted on the horizontal axis L ₁ -L _0, the vertical axis L _e -L _0. A solid line 300 shown in FIG. 15 is an approximate straight line obtained from the plot by the least square error method. The inclination of this approximate line is determined as the enhancement coefficient α.

In this way, the enhancement coefficient α is determined based on the value of L ₁ −L ₀ . That is, the initial enhancement gradation _Le is determined based on the value of L ₁ −L ₀ . The enhancement coefficient α is determined in the gate array 104. Further, the process of calculating the enhancement coefficient α according to the embodiment corresponds to the process in the calculation formula determination step described in the claims. The solid line 300 determined by the least square error method corresponds to the output value calculation formula described in the claims.

  The enhancement correction coefficient β is calculated by (Equation 5) using the edge strength of the edge detection image, as in the first embodiment. The enhancement correction coefficient β may be calculated by any one of (Expression 6) to (Expression 8) instead of (Expression 5).

ここで、βは０以上の実数である。よって、βは、例えば下の（式１１）から（式１２）のいずれかを用いて求める。

As another example, the enhancement coefficient multiplication unit 110 may obtain the enhanced video information by (Expression 10) instead of (Expression 9).

Here, β is a real number of 0 or more. Therefore, β is obtained, for example, using any one of (Equation 11) to (Equation 12) below.

  The gradation information conversion unit 112 converts the luminance information and the color difference information into the enhanced gradation information of the three primary colors, and the enhanced gradation information is displayed on the liquid crystal display device 20. The gradation information conversion unit 112 converts enhanced video information including luminance information and color difference information into enhanced primary color information of three primary colors.

ここで、（Ｒ_c，Ｇ_c，Ｂ_c）はそれぞれ、赤、緑、青の強調階調である。なお、上記３×３のマトリックスは、一例であり、その他の係数でも構わない。 The liquid crystal display device 20 performs display by writing gradation in the sub-pixels of the three primary colors of red, green, and blue. Therefore, conversion processing is performed to adapt to the display format of the liquid crystal display device 20. The conversion by the gradation information conversion unit 112 can be obtained by matrix conversion shown in (Equation 15).

Here, (R _c , G _c , B _c ) are red, green, and blue enhancement gradations, respectively. The 3 × 3 matrix is an example, and other coefficients may be used.

ここで、（Ｒ₁，Ｇ₁，Ｂ₁）は、第２フレームの赤、緑、青の三原色画像情報を示しており、（Ｒ₀，Ｇ₀，Ｂ₀）は、第１フレームの赤、緑、青の三原色画像情報を示している。また、（Ｒ_c，Ｇ_c，Ｂ_c）は、強調された赤、緑、青の三原色画像情報を示している。同様に、（式１０）は、（式１７）のように書き換えられる。

In the above description, the input video information is composed of luminance information (Y) and color difference information (U, V). However, even if the input video information is red, green, and blue primary color image information. I do not care. In this case, as shown in FIG. 16, the configuration of the moving image processing apparatus is a configuration in which the gradation information conversion unit is omitted from the configuration shown in FIG. Further, (Equation 9) can be rewritten as (Equation 16).

Here, (R ₁ , G ₁ , B ₁ ) indicates red, green, and blue primary color image information of the second frame, and (R ₀ , G ₀ , B ₀ ) indicates red of the first frame. , Green and blue three primary color image information. In addition, (R _c , G _c , B _c ) indicates emphasized three primary color image information of red, green, and blue. Similarly, (Expression 10) can be rewritten as (Expression 17).

  The other configuration and processing of the moving image processing apparatus 10 according to the second embodiment are the same as the configuration and processing of the moving image processing apparatus 10 according to the first embodiment.

  As described above, the moving image processing apparatus 10 according to the second embodiment can also process video information to improve the sharpness of the moving image displayed on the liquid crystal display device 20. Thereby, a high-quality moving image can be presented to the observer.

(Embodiment 3)
Next, the moving image processing apparatus 10 according to the third embodiment will be described. The basic configuration of the moving image processing apparatus 10 according to the third embodiment is the same as the configuration of the moving image processing apparatus 10 according to the first embodiment.

  In the moving image processing apparatus 10 according to the third embodiment, when the absolute value of the inter-frame difference value between the first frame and the second frame is equal to or less than a predetermined value, the gate array 104 has an edge with respect to the region. Do not perform emphasis processing. In this respect, the moving image processing apparatus 10 according to the third embodiment is different from the moving image processing apparatus 10 according to the other embodiments.

  In the first embodiment, the enhancement correction coefficient β in (Expression 4) used by the gate array 104 is obtained by (Expression 5) described in the first embodiment.

ここで、Ｌ_thは、所定の閾値を表している。Ａｂｓ（ｘ）は、ｘの絶対値を表している。また、実施の形態３においては、（式２０）により、強調階調Ｌ_cを求める。

The gate array 104 according to the third embodiment obtains the enhancement correction coefficient β ′ by applying (Equation 18) and (Equation 19) to the enhancement correction coefficient β obtained by (Equation 5).

Here, L _th represents a predetermined threshold value. Abs (x) represents the absolute value of x. In the third embodiment, the enhancement gradation L _c is obtained from (Equation 20).

That is, when the interframe difference L ₁ −L ₀ is equal to or less than the threshold value L _th , the enhancement correction coefficient β ′ is set to 1 and over-emphasis is not performed. As described above, when the interframe difference L ₁ −L ₀ is equal to or smaller than the threshold L _th , the enhancement correction coefficient β ′ is set to 1 to prevent over-enhancement of noise components.

  The noise component in the image may be detected as an edge by the edge detection unit 102. Further, the noise changes with time. Therefore, in the moving image processing apparatus 10 according to the first embodiment, noise may be overemphasized as an edge portion of a moving object.

Therefore, in the moving image processing apparatus 10 according to the third embodiment, when the interframe difference L ₁ −L ₀ is equal to or less than the threshold L _th , the enhancement correction coefficient β ′ is set to 1 so that the change is small like noise. Regarding the area, it was decided not to overemphasize. Thereby, it is possible to prevent over-emphasis of the noise component of the image.

The threshold value L _th is desirably obtained from the S / N of the input video information, but it may be normally a value of about 10.

  The remaining configuration and processing of the moving image processing apparatus 10 according to the third embodiment are the same as the configuration and processing of the moving image processing apparatus 10 according to the first embodiment.

(Embodiment 4)
Next, the moving image processing apparatus 10 according to the fourth embodiment will be described. The basic configuration of the moving image processing apparatus 10 according to the fourth embodiment is the same as the configuration of the moving image processing apparatus 10 according to the second embodiment.

  In the moving image processing apparatus 10 according to the fourth embodiment, as in the moving image processing apparatus 10 according to the third embodiment, the absolute value of the inter-frame difference value of the luminance information Y between the first frame and the second frame is predetermined. When the value is equal to or smaller than the value, the gate array 104 does not perform edge enhancement processing on the region.

The gate array 104 of the moving image processing apparatus 10 according to the fourth embodiment applies the (Equation 21) and (Equation 22) to the enhancement correction coefficient β obtained by (Equation 5) to obtain the enhancement correction coefficient β ″. Ask.

すなわち、過強調を行わない場合、（式１０）に示す強調補正係数は０である。したがって、ΔＹが閾値Ｙ_th以下の場合にβを０とする。 Further, when the emphasized video information is obtained by (Equation 10), the enhancement correction coefficient β ″ is obtained by (Equation 23) instead of (Equation 21).

That is, when overemphasis is not performed, the enhancement correction coefficient shown in (Expression 10) is 0. Therefore, β is set to 0 when ΔY is equal to or less than the threshold value Y _th .

  The other configuration and processing of the moving image processing apparatus 10 according to the fourth embodiment are the same as the configuration and processing of the moving image processing apparatus 10 according to the second embodiment.

  As described above, also in the moving image processing apparatus 10 according to the fourth embodiment, the sharpness of the moving image displayed on the liquid crystal display device 20 can be improved. Thereby, a high-quality moving image can be presented to the observer.

(Embodiment 5)
Next, the moving image processing apparatus 10 according to the fifth embodiment will be described. The basic configuration of the moving image processing apparatus 10 according to the fifth embodiment is the same as the configuration of the moving image processing apparatus 10 according to the first to fourth embodiments.

  The moving image processing apparatus according to the fifth embodiment determines the enhancement gradation by a process different from the process according to the other embodiment when the frame rate of the input video information is different from the refresh rate of the liquid crystal display device. In this respect, the moving image processing apparatus 10 according to the fifth embodiment is different from the moving image processing apparatus 10 according to the other embodiments.

  FIG. 17 is a diagram illustrating the relationship between the frame rate of the input image and the refresh rate of the liquid crystal display device 20. FIG. 17 shows 30 fps input video information. Specifically, continuous frames “A”, “B”, and “C” are shown. The horizontal axis indicates time. The refresh rate of the liquid crystal display device according to this embodiment is 60 Hz. In this case, as shown in FIG. 17, when the input video information of 30 fps continues from “A” → “B” → “C”, the liquid crystal display device 20 “A” → “A” → The same frame is displayed twice, “B” → “B” → “C” → “C”.

  Therefore, at the refresh timing of the liquid crystal display device 20, when changing to a different frame (for example, “A” → “B”) and when displaying the same frame repeatedly (for example, “B” → “B”) ]) Are repeated alternately.

  When the same frame is repeatedly displayed on the liquid crystal display device 20 by the same process as described in other embodiments, flicker occurs.

  For example, when the first “A” is written to the liquid crystal display device 20 with the emphasized gradation, and then the second “A” is written with the initial emphasized gradation, the liquid crystal display device 20 has the enhanced gradation. The frame written in step 1 and the frame written in the initial emphasis gradation are alternately shown every 1/60 seconds. Therefore, flicker having a period of 1/30 second occurs.

  Further, when both the first “A” and the second “A” are written in the emphasized gradation, the gradation that is equal to or higher than the appropriate gradation value is displayed at the timing of displaying the second “A”. Reach the value. That is, it becomes overemphasized.

ここで、Ｌ_ecは、エッジ補正フレームにおけるエッジ補正階調を示している。係数ｒは０〜１の係数を示している。（式２４）は、（β−１）（Ｌ_e−Ｌ₁）で表される過強調量に対し係数ｒを乗じ、Ｌ₁を加算した過強調の到達階調を示している。 Therefore, in the moving image processing apparatus 10 according to the fifth embodiment, in the second display of the same frame, the second enhancement gradation L _ec shown in (Equation 24) is written in the edge region to be enhanced. .

Here, L _ec indicates the edge correction gradation in the edge correction frame. The coefficient r indicates a coefficient from 0 to 1. (Equation 24) represents the over-emphasized reached gradation obtained by multiplying the over-emphasis amount represented by (β-1) (L _e -L ₁ ) by a coefficient r and adding L ₁ .

The coefficient r is a coefficient for correcting a response delay of the liquid crystal display device. When the over-emphasis represented by (β-1) (L _e -L ₁ ) is written on the liquid crystal display device, (β-1) ( L _e -L ₁₎ of the can not reach excessive emphasis amount. Therefore, the actual reached gradation is corrected by multiplying by a coefficient of 0 to 1. Note that r is a value determined by the response characteristics of the liquid crystal display device. r may be calculated based on an actual measurement value. Then, the gate array 104 writes the second emphasized gradation _Lec calculated by (Equation 24).

Note that the difference value between the second enhancement coefficient _Lec and the initial enhancement gradation L _{1 according} to the embodiment corresponds to the second correction amount described in the claims.

FIG. 18 is a flowchart of the moving image processing performed by the moving image processing apparatus 10 according to the fifth embodiment. In the present embodiment, after detecting the edge strength in step S106, the gate array 104 acquires the refresh rate of the liquid crystal display device 20 (step S108). Next, the frame rate of the input image is compared with the refresh rate of the liquid crystal display device 20 (step S122). When the frame rate of the input image is larger than the refresh rate of the liquid crystal display device 20 (No in step S122), the gate array 104 is emphasized based on the edge strength, like the gate array 104 according to the first embodiment. The correction coefficient β is determined, and the enhancement gradation L _c is determined by (Equation 4) (step S124). Next, the determined gradation is written (step S126).

On the other hand, when the frame rate of the input image is smaller than the refresh rate of the liquid crystal display device 20 (No at Step S122), the second emphasis gradation _Lec is determined by the above (Equation 24) (Step S130).

  Thus, the moving image processing according to the fifth embodiment is completed. The other processing steps are the same as the processing of the same step number described in the first embodiment with reference to FIG.

ここで、（Ｙ_ec，Ｕ_ec，Ｖ_ec）は、それぞれ、エッジ補正フレームの輝度及び色差情報を表している。 As another example, the second enhancement gradation for the second embodiment in which the enhancement frame is determined by (Equation 9) is calculated by (Equation 25) instead of (Equation 24).

Here, (Y _ec , U _ec , V _ec ) represent the luminance and color difference information of the edge correction frame, respectively.

（式２６）を（Ｙ_x，Ｕ_x，Ｖ_x）について解くと、（式２５）が得られる。 (Equation 25) can be derived as follows. When the gradation reached by the liquid crystal display device according to (Equation 9) is (Y _x , U _x , V _x ), the following equation is established.

Solving (Equation 26) for (Y _x , U _x , V _x ) yields (Equation 25).

なお、実施の形態にかかるβ／αは、特許請求の範囲に記載の第２強調補正係数に相当し、βは、特許請求の範囲に記載の第１強調補正係数に相当する。 As another example, the second enhancement gradation for the second embodiment in which the enhancement frame is determined by (Equation 10) is calculated by (Equation 27) instead of (Equation 24).

Note that β / α according to the embodiment corresponds to the second emphasis correction coefficient described in the claims, and β corresponds to the first emphasis correction coefficient described in the claims.

（式２８）を（Ｙ_x，Ｕ_x，Ｖ_x）について解くと、（式２７）が得られる。 (Expression 27) can be derived as follows. When the gradation reached by the liquid crystal display device according to (Expression 10) is (Y _x , U _x , V _x ), the following expression is established.

When (Equation 28) is solved for (Y _x , U _x , V _x ), (Equation 27) is obtained.

When the input video information is red, green, and blue primary color image information, the edge correction frame is obtained by replacing (Y, U, V) in (Equation 25) and (Equation 27) with (R, G, B). Can be obtained (R _ec , G _ec , B _ec ).

  As described above, also in the moving image processing apparatus according to the fifth embodiment, the sharpness of moving images displayed on the liquid crystal display device can be improved. Thereby, a high-quality moving image can be presented to the observer.

  As mentioned above, although embodiment regarding the display method of the liquid crystal display device 20 concerning this invention was described, this invention is not limited to the said embodiment, It implements in various deformation | transformation within the range which does not deviate from the meaning. Is possible. Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining the disclosed constituent elements. For example, even if some constituent elements are deleted from the disclosed constituent requirements, the invention can be extracted as long as a predetermined effect can be obtained.

10 moving image processing device 20 liquid crystal display device 51 CPU
52 ROM
53 RAM
57 Communication I / F
62 bus 100 frame memory 102 edge detection unit 104 gate array 106 array data holding unit 110 enhancement coefficient multiplication unit 112 gradation information conversion unit

Claims (12)

A moving image processing device for processing a moving image to be displayed on a liquid crystal display device,
A pixel value at a predetermined position in the first frame included in the moving image, and a position corresponding to the predetermined position in the second frame continuously arranged in the time axis direction with the first frame. Output value determination means for determining an output value of the pixel at the predetermined position of the second frame based on the degree of response delay that occurs when the liquid crystal display device displays a moving image with reference to the pixel value When,
Edge region detection means for detecting an edge region from the second frame;
Output value correction means for correcting the output value so that the absolute value of the difference between the output value and the pixel value at the predetermined position in the second frame becomes larger with respect to the detected edge region. And a moving image processing apparatus. A difference value calculating means for calculating a difference value between a pixel value at a position corresponding to the predetermined position in the second frame and a pixel value at the predetermined position in the first frame;
2. The output value determination unit according to claim 1, wherein the output value determination unit determines the output value of a pixel at the predetermined position of the second frame based on the difference value and the response delay level. Movie processing device.   The moving image processing apparatus according to claim 1, wherein the edge area detection unit detects an edge area based on a luminance component at each position in the second frame. Edge strength calculating means for calculating edge strength in the edge region of the second frame detected by the edge region detecting means;
Correction amount determination means for determining a correction amount to be corrected in the output value correction means based on the edge strength calculated in the edge strength calculation means;
The output value correcting means determines the output value corresponding to the predetermined position determined by the output value determining means, and the pixel value corresponding to the predetermined position in the first frame from the output value. When the subtracted difference value is greater than 0, the value is corrected to a value that is larger by the correction amount determined by the correction amount determination unit, and when the difference value is less than 0, the correction amount determination unit determines the correction value. The moving image processing apparatus according to claim 1, wherein the correction is made to a value that is smaller by a correction amount.   The moving image processing apparatus according to claim 4, wherein the correction amount determination unit determines the correction amount proportional to the edge strength.   The output value correcting means is an emphasis correction greater than 1 obtained by the correction amount determining means to a value obtained by subtracting the pixel value at the predetermined position of the second frame from the output value at the predetermined position. 6. The moving image processing apparatus according to claim 4, wherein the corrected output value is determined from a value multiplied by a coefficient. The output value determining means multiplies the difference value calculated by the difference value calculating means by a predetermined enhancement coefficient based on the degree of response delay that occurs when the liquid crystal display device displays a moving image. Determining the output value;
The output value correction means determines the corrected output value by adding a pixel value at the predetermined position in the first frame to a value obtained by multiplying the output value by the enhancement correction coefficient. The moving image processing apparatus according to claim 6. The output value determining means multiplies the difference value calculated by the difference value calculating means by a predetermined enhancement coefficient based on the degree of response delay that occurs when the liquid crystal display device displays a moving image. Determining the output value;
The output value correction means determines the corrected output value by adding a value obtained by multiplying the difference value by the enhancement correction coefficient and a pixel value at the predetermined position of the first frame to the output value. The moving image processing apparatus according to claim 6.   The moving image processing apparatus according to any one of claims 1 to 8, wherein the output value determining unit determines an output value for each of the three primary colors red, green, and blue displayed on the liquid crystal display device.   The moving image processing apparatus according to any one of claims 1 to 9, wherein the output value determining means determines an output value for each of a luminance component and a color difference component in the second frame. A moving image processing method for processing a moving image to be displayed on a liquid crystal display device,
A pixel value at a predetermined position in the first frame included in the moving image, and a position corresponding to the predetermined position in the second frame continuously arranged in the time axis direction with the first frame. An output value determining step of determining an output value of a pixel at the predetermined position of the second frame based on a degree of response delay caused when the liquid crystal display device displays a moving image with reference to a pixel value When,
An edge region detection step of detecting an edge region from the second frame;
An output value correction step for correcting the output value so that the absolute value of the difference between the output value and the pixel value at the predetermined position in the second frame becomes larger with respect to the detected edge region. And a moving image processing method. A moving image processing program for causing a computer to execute moving image processing for processing a moving image to be displayed on a liquid crystal display device,
A pixel value at a predetermined position in the first frame included in the moving image, and a position corresponding to the predetermined position in the second frame continuously arranged in the time axis direction with the first frame. An output value determination function that determines an output value of a pixel at the predetermined position of the second frame based on a degree of response delay that occurs when the liquid crystal display device displays a moving image with reference to a pixel value When,
An edge region detection function for detecting an edge region from the second frame;
Output value correction function for correcting the output value so that the absolute value of the difference between the output value and the pixel value at the predetermined position in the second frame becomes larger with respect to the detected edge region And a moving image processing program.

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