JP2006208854A - Image processor, program, recording medium, and image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor capable of simultaneously reducing animation blurring and flicker in one screen of a liquid crystal display panel. <P>SOLUTION: The image processor has an operation means for calculating first difference between a value of a first pixel included in an image at first time and a value of the first pixel at second time; a first judgment means for judging whether or not magnitude of the first difference is larger than at least one of at least one first reference values indicating reference magnitude of the first difference; and an adjustment means for adjusting the value of the first pixel at the second time so that the value of the first pixel at the second time approaches the value of the first pixel at the first time, based on judgment results of the first judgment means or adjusting the value of the first pixel at the second time so that the value of the first pixel at the second time keeps away from the value of the first pixel in the first time. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image processing apparatus, a program, a recording medium on which a program is recorded, and an image display apparatus including the image processing apparatus. According to the image processing device, the program, the recording medium, and the image display device of the present invention, it is possible to simultaneously reduce moving image blur and flicker within the same screen of the liquid crystal display panel.

  Japanese Patent Laid-Open No. 4-288589 (Patent Document 1) discloses a method of reducing moving image blur (image blur due to an afterimage) of a liquid crystal display panel. Specifically, the level fluctuation in the time axis direction of a plurality of pixels included in the liquid crystal display panel is detected by referring to the image signal and the input image signal stored in the field image storage circuit. Then, a high frequency enhancement filter is applied to the input image signal in the time axis direction of the plurality of pixels according to the detected level fluctuation. As a result, the response speed of halftone display can be increased, and moving image blur can be reduced.

  Further, Japanese Patent Laid-Open No. 2002-189458 (Patent Document 2) discloses another method for reducing moving image blur of a liquid crystal display panel. The difference between the luminance gradation of the video data indicating the frame at the first time stored in the storage means and the luminance gradation of the video data indicating the frame (current frame) at the second time following the first time is calculated. The correction value corresponding to the calculated difference and the luminance gradation of the video data indicating the current frame are calculated. As a result, it is possible to sufficiently cope with a signal indicating a fast moving image and reduce moving image blur.

  On the other hand, Japanese Patent Laid-Open No. 5-191750 (Patent Document 3) reduces screen flicker by switching the enhancement processing in the time axis direction according to a video signal obtained by converting a MUSE signal and a normal current video signal, A method for preventing flicker is disclosed.

Japanese Patent Laid-Open No. 7-104726 (Patent Document 4) discloses a display data generation method for preventing flicker and flicker of an image displayed on a liquid crystal display panel.
JP-A-4-288589 JP 2002-189458 A JP-A-5-191750 JP-A-7-104726

  For example, when a moving image is displayed on the liquid crystal display panel, an afterimage (moving image blur) or flicker (flicker) may occur on the liquid crystal display panel depending on the characteristics of the image. Movie blur and flicker significantly impair image quality. However, flicker cannot be reduced by the methods disclosed in Patent Document 1 and Patent Document 2. Also, with the methods disclosed in Patent Document 3 and Patent Document 4, moving image blur cannot be reduced.

  As disclosed in Patent Documents 1 to 4, in the conventional technique, if the difference component (high frequency emphasis signal) that enhances the high frequency component of the input image frequency is increased in order to reduce moving image blur, flicker is generated. stand out. On the other hand, when the high frequency component (low frequency transmission signal) of the input image is attenuated in order to reduce flicker, moving image blur becomes conspicuous. Conventionally, there has been no method for reducing motion blur and flicker simultaneously and within the same screen.

  Whether moving image blur or flicker occurs in the input image depends largely on the characteristics of the input image as well as the characteristics of the liquid crystal display panel (display means). Flicker is likely to occur when displaying a character image or line drawing that has many high frequency components and changes sharply, and moving image blur tends to occur when a landscape image or a person image having a relatively low spatial frequency component is displayed. There are factors that degrade image quality in accordance with image information, and a method for solving these simultaneously is demanded.

  Although it is conceivable to separately prepare a circuit for creating a video enhancement signal and a circuit for creating a low-frequency transmission signal, and switching between a circuit that creates a video enhancement signal and a circuit that generates a low-frequency transmission signal, the device is complicated. become.

  The present invention has been made in view of the above problems, and image flickering caused by the value of the first pixel at the second time being different from the value of the first pixel at the first time, and An image processing apparatus, a program, a recording medium storing the program, and an image display apparatus capable of reducing an afterimage of an image caused by the value of the first pixel at the second time being close to the value of the first pixel at the first time The purpose is to provide.

  The image processing apparatus of the present invention is a first pixel included in an image, and is a first difference between a value of the first pixel at a first time and a value of the first pixel at a second time following the first time. And first determination means for determining whether the magnitude of the first difference is greater than at least one of at least one first reference value indicating a reference magnitude of the first difference. And the first pixel at the second time so that the value of the first pixel at the second time approaches the value of the first pixel at the first time based on the determination result of the first determination means. Or adjusting the value of the first pixel at the second time so that the value of the first pixel at the second time is away from the value of the first pixel at the first time. Means. There is achieved.

  The first determination unit may determine whether the magnitude of the high frequency component in the first pixel calculated by the calculation unit as the first difference is greater than at least one of at least one reference value. Good.

  The adjusting means generates inversion information indicating whether to invert the sign of the first difference based on the first difference and coefficient information indicating an amplification coefficient for the first difference, and the adjusting means , Determining an adjustment amount of the value of the first pixel at the second time based on the generated inversion information and the generated coefficient information, and the adjustment means sets the adjustment amount by the determined adjustment amount. The value of the first pixel at the second time may be adjusted.

  The image processing apparatus further includes a first storage unit that stores at least one table, and the at least one table includes a correspondence relationship between inversion information and the magnitude of the first difference, coefficient information, and the first difference. It represents at least one of the correspondences with the magnitude, the inversion information indicates whether to invert the sign of the first difference, and the coefficient information indicates an amplification coefficient for the first difference. Good.

  Each of the inversion information and the coefficient information may be nonlinearly associated with the first difference.

  The first storage means may be constituted by a digital memory.

  The amount of adjustment of the value of the first pixel at the second time is associated with the first difference, and the adjusting means is the amount of adjustment at the second time by the amount of adjustment corresponding to the calculated first difference. The value of the first pixel may be adjusted.

  The adjustment amount of the value of the first pixel at the second time may be nonlinearly associated with the first difference.

  The image processing apparatus may further include a second storage unit that stores information indicating the adjustment amount, and the second storage unit may be configured by a digital memory.

  The computing means is a second pixel included in the image, further obtains a second difference between a value of the second pixel at the first time and a value of the second pixel at the second time, The two pixels are different from the first pixel, and the first determination unit includes the second reference value of at least one second reference value in which a magnitude of the second difference indicates a reference magnitude of the second difference. A second determination unit configured to determine whether or not the value is greater than at least one; and the adjustment unit determines the value of the one pixel at the second time and the second time based on a determination result of the second determination unit. The value of the two pixels may be adjusted.

  The program of the present invention is a program for causing a computer to execute image processing. The image processing is (a) a first pixel included in an image, and the value of the first pixel at a first time and the Obtaining a first difference from a value of the first pixel at a second time following the first time; and (b) at least one of which a magnitude of the first difference indicates a reference magnitude of the first difference A step of determining whether or not it is greater than at least one of the first reference values; and (c) based on the determination result of step (b), the value of the first pixel at the second time is the first The value of the first pixel at the second time is adjusted so as to approach the value of the first pixel at one time, or the value of the first pixel at the second time is the first value at the first time. Away from pixel value The value of the first pixel in the second time includes a step of adjusting to, thereby, the above-mentioned object can be achieved.

  The recording medium of the present invention is a computer-readable recording medium that records a program for causing a computer to execute image processing. The image processing includes (a) a first pixel included in an image, and Obtaining a first difference between a value of the first pixel at one time and a value of the first pixel at a second time following the first time; and (b) the magnitude of the first difference is the first difference. Determining whether or not it is greater than at least one of at least one first reference value indicating the reference magnitude of the reference, and (c) based on the determination result of step (b), the second time The value of the first pixel at the second time is adjusted so that the value of the first pixel at the second time approaches the value of the first pixel at the first time, or the value of the first pixel at the second time is adjusted. The value is Includes the step of adjusting the value of the first pixel in the second time away from the value of the first pixel in one time, thereby the objective described above being achieved.

  The image display device of the present invention includes the image processing device and display means for displaying the image including the first pixel having the adjusted value, thereby achieving the above object.

  According to the image processing device, the program, the recording medium, and the image display device of the present invention, the value of the first pixel at the second time is such that the value of the first pixel at the second time approaches the value of the first pixel at the first time. The value can be adjusted, or the value of the first pixel at the second time can be adjusted such that the value of the first pixel at the second time moves away from the value of the first pixel at the first time. As a result, the flicker of the image caused by the value of the first pixel at the second time being different from the value of the first pixel at the first time, and the value of the first pixel at the second time are the first time. The afterimage of the image caused by being close to the value of the first pixel in can be reduced.

  According to the image processing device, the program, the recording medium, and the image display device of the present invention, by controlling the signal to be added to the image signal according to the image information, moving image blur and flicker can be prevented within the same screen of the liquid crystal display panel. It can be reduced at the same time.

  Embodiments of the present invention will be described below with reference to the drawings.

1. Embodiment 1
FIG. 1 shows a configuration of an image display apparatus 100 according to Embodiment 1 of the present invention. The image display device 100 includes an image processing device 200 and an image display unit 5.

  The image processing apparatus 200 includes a frame memory 1 that stores data representing an image, a differentiator 2 that generates a difference image, a filter circuit 3, an arithmetic unit 4 that adds or subtracts a plurality of data, and an image characteristic determination Part 6. The filter circuit 3 includes an inverter 31 and an amplifier 32.

  The frame memory 1 and the differentiator 2 obtain a difference between the value of the predetermined pixel at the first time (t−1) and the value of the predetermined pixel at the second time (t) following the first time.

  The image characteristic determining unit 6 determines whether or not the difference obtained by the frame memory 1 and the differentiator 2 is greater than at least one of at least one reference value indicating the reference size of the difference. To do. The determination result of the image characteristic determination unit 6 is input to the filter circuit 3. Details of the operation of the image characteristic determination unit 6 will be described later.

  Based on the determination result of the image characteristic determination unit 6, the filter circuit 3 and the arithmetic unit 4 change the predetermined pixel value at the second time (t) to the predetermined pixel value at the first time (t−1). The value of the predetermined pixel at the second time (t) is adjusted so as to approach, or the value of the predetermined pixel at the second time (t) moves away from the value of the first pixel at the first time (t−1). Thus, the value of a predetermined pixel at the second time (t) is adjusted.

  The image display unit 5 displays an image. This image includes predetermined pixels having values adjusted by the filter circuit 3 and the arithmetic unit 4.

  Hereinafter, the operation of the image display apparatus 100 will be described with reference to FIG.

  Image data indicating an image is input to the frame memory 1, the differentiator 2, and the image characteristic determination unit 6. The differentiator 2 generates difference image data Δ indicating a difference image based on the data (f−1) indicating the delayed image and the data (f) indicating the input image stored in the frame memory 1. The difference image data Δ is sent to the filter circuit 3.

  The filter circuit 3 includes an inverter 31 and an amplifier 32. The inverter 31 and the amplifier 32 are controlled based on an external signal such as a signal determined by the image characteristic determination unit 6. For example, the inverter 31 is controlled based on the inversion information. The inversion information indicates whether to invert the sign of the difference image data Δ. For example, the amplifier 32 is controlled based on the amplification coefficient for the difference image data Δ. The shaped image data and the input image data output from the filter circuit 3 are processed by the calculator 4, and the processed data is output to the image display unit 6.

  For example, in the case of video data processing, image data input to the image processing apparatus 200 can be obtained from a luminance signal processing channel. In the case of RGB separate data processing, image data input to the image processing apparatus 200 can be obtained from each channel.

  FIG. 2 is a diagram for explaining the principle of the present invention.

  FIG. 2A shows a delayed image one frame before and the current image. The delayed image one frame before is indicated by the delayed image data (f-1), and the current image is indicated by the image data (f). The image moves from the delayed image one frame before to the current image as time elapses.

  FIG. 2B shows the cross-sectional luminance of the delayed image one frame before and the cross-sectional luminance of the current image.

  FIG. 2C shows the difference image data Δ. The differentiator 2 calculates a difference ((f−1) − (f)) between the delayed image data (f−1) and the image data (f), and generates difference image data Δ.

  FIG. 2D shows inverted data (−Δ) of the difference image data Δ. The inverter 31 generates inverted data (−Δ). Difference data with different polarities can be obtained by the inverter 31, and the calculation for generating the data (−Δ) is the same as the calculation for generating ((f) − (f−1)).

  Conventionally, a high frequency emphasis signal is generated by calculating a difference signal with a current signal, and the generated high frequency emphasis signal is output to the image display unit 5. The present invention can obtain a high-frequency emphasis signal and a low-frequency transmission signal of an input image with a simple configuration by adjusting image amplification information and switching signals.

  FIG. 3 shows the relationship between the amplification information α and the difference image data Δ.

  FIG. 3A shows the relationship between the amplification information (α> 1) and the difference image data Δ. The edges of the difference image are emphasized. The frequency characteristic of the difference image is a characteristic in which the high frequency is emphasized (high frequency emphasis A), and improves the motion blur. The edge of the difference image is emphasized as α increases, and the effect of improving the motion blur is increased.

  FIG. 3B shows the relationship between the amplification information (α = 1) and the difference image data Δ. The difference image data Δ is Δ = (f−1). It is the same as the delayed image data and has no filter effect.

  FIG. 3C shows the relationship between the amplification information (0 <α <1) and the difference image data Δ. The difference image data Δ is in a state where the current image data (f) is expanded (blurred). The frequency characteristic of the difference image is a characteristic in which the high-frequency is attenuated (low-frequency transmission signal), and improves flicker. When α = 0.5, the shape of the difference image data Δ is symmetrical.

  FIG. 3D shows the relationship between the amplification information (α = 0) and the difference image data Δ. The difference image data Δ is Δ = f. It is the same as the current image data (f) and has no filter effect.

  FIG. 3E shows the relationship between the amplification information (α <0) and the difference image data Δ. The edges of the difference image are emphasized. The frequency characteristic of the difference image is a characteristic in which the high frequency is emphasized (high frequency emphasis B), and improves the motion blur. The edge of the difference image is emphasized as α decreases, and the effect of improving the motion blur is increased. When the high frequency emphasis A (see FIG. 3A) is compared with the high frequency emphasis B, the direction in which the image showing the moving object is emphasized is different, and the high frequency emphasis A and the high frequency emphasis B are different depending on the image. Generally, a characteristic (high frequency emphasis B) in which the edge of the difference image becomes brighter in the moving direction of the object is preferable.

  Here, the amplification information (amplification degree) α being negative (minus) is equivalent to inverting the polarity of the difference image data and making the amplification degree α positive (plus). In order to achieve the high frequency emphasis B (see FIG. 3E) when the amplification degree α is positive, the polarity inversion output −Δ (see FIG. 2D) from the inverter 31 is used. Filter circuit. For example, the difference image data Δ when α = −0.5 is equivalent to the data output from the inverter 31 by inputting the difference image data Δ into the inverter 31 when the amplification factor = 0.5. It is.

  When 0 <α <1 (see FIG. 3C), if the signal is inverted by the inverter 31 and added to the current signal, it becomes a high frequency emphasis signal, and is added to the current signal without using the inverter 31 Then, it becomes a low-pass transmission signal. A high-frequency emphasis signal and a low-frequency transmission signal can be obtained by simple signal switching.

  As described with reference to FIG. 3, the calculation unit 4 adds the current image signal (f) and the signal output from the filter unit 3, while the calculation unit 4 adds the current image signal (f) and the filter unit 3. It is possible to subtract from the signal output from. Even when the calculation unit 4 subtracts the current image signal (f) and the signal output from the filter unit 3, a high frequency emphasis signal and a low frequency transmission signal can be obtained with a simple configuration by signal switching of the present invention. .

  As described with reference to FIG. 3, according to the present invention, the difference image data Δ is not multiplied as it is, but the difference image data Δ is multiplied by α, thereby correcting the motion blur and moving image. The image enhancement effect can be arbitrarily controlled.

  FIG. 4 shows the relationship between the inversion information, the amplification degree, the type of calculation unit, and the image characteristics. The image characteristics are determined according to the combination of the inversion information, the amplification degree, and the type of calculation unit. Specifically, it indicates whether a high-frequency emphasis signal is obtained or a low-frequency transmission signal is obtained according to the combination of the inversion information, the amplification degree, and the type of calculation unit. The amplification degree α is positive (plus). The subtraction processing by the arithmetic unit 4 is equivalent to a combination of signal polarity inversion processing and addition processing.

  In the embodiment of the present invention, the setting of the degree of amplification α and whether to use an inverter are determined by an external signal. For example, the setting of the amplification degree α and whether or not to use an inverter may be manually determined in advance by an external signal based on image information. Further, the setting of the amplification degree α and whether or not to use the inverter may be determined by the image characteristic determination unit 6. Furthermore, the order in which the inverter 31 and the amplifier 32 are provided does not matter. For example, the amplifier 32 may be provided on the upstream side of the inverter 31.

  The image characteristic determination unit 6 determines the high frequency component of the frequency of the input image data, outputs the inversion information to the inverter 31, and further outputs the amplification information α to the amplifier 32, thereby improving the motion blur and flicker. Make improvements.

  For example, a high frequency component is detected based on the difference image data Δ. The difference image data Δ corresponds to a high frequency component of the input image frequency, and the image characteristic determination unit 6 determines the inversion information and the amplification degree α according to the magnitude of the high frequency component.

  FIG. 5 shows the configuration of the image characteristic determination unit 6. The image characteristic determination unit 6 includes a frame memory 6a, a difference unit 6b, an absolute value calculator 6c, and an inversion controller 6d.

  The differentiator 6b calculates the difference between the input image data and the delayed image data stored in the frame memory 6a, and generates difference image data (difference information). The absolute value calculator 6c calculates the absolute amplitude value of the difference image data based on the generated difference image data. The absolute amplitude value of the difference image data represents the strength of the frequency component of the image. For example, a large absolute value indicates that the frequency component of the differential image data is a high frequency component, and a small absolute value indicates that the frequency component of the differential image data is a low frequency component. Absolute value data indicating the absolute amplitude of the difference image data is input to the inversion controller 6d, and the inversion controller 6d calculates the amplification degree α based on the absolute value data.

  If the absolute value indicated by the absolute value data is equal to or greater than a predetermined value (for example, 90% or more of the maximum value), the image characteristic determination unit 6 determines that the image is likely to cause flicker, and 0 <α Inversion information having a value of <1 (for example, α = 0.5) is output, and an inversion signal (for example, no inversion signal is output in this case) is output. The image processing apparatus 200 of the present invention generates a low-pass transmission type signal with reference to the inversion information α.

  When the absolute value indicated by the absolute value data is smaller than a predetermined value (for example, 90% or less of the maximum value), the image characteristic determination unit 6 determines an α value (for example, α = [% Of maximum amplitude] × 2) is output and an inverted signal is output. The calculation of α according to the absolute value is not limited to a linear relationship but may be a table conversion as a non-linear relationship.

  The embodiment described with reference to FIG. 5 is an example in which the low-frequency transmission and the high-frequency emphasis B are achieved at the same time in the case division shown in FIG. The effects of the present invention can be achieved by other combinations in the configuration of the image processing apparatus.

  The amplification degree α may be arbitrarily determined according to the image, but 0 <α <1 is necessary to obtain a low-frequency transmission signal, and α> 1 or α <0 to obtain a high-frequency enhancement signal. is required.

  As a simple embodiment of the value of α, the value of α is fixed to 0.5, and when the absolute value of the difference image is equal to or greater than a predetermined value, an inversion signal is not output, and when it is equal to or smaller than the predetermined value, A high-frequency emphasis signal and a low-frequency transmission signal can be generated simply by outputting an inverted signal, and flicker reduction and moving image blur improvement according to the state of the image can be achieved simultaneously.

  In the image characteristic determination unit 6, when the image data includes character image data and natural image data, if the difference image data is calculated over the entire screen, the high frequency component of the character image portion is large and the natural image portion is high. Since the area component is smaller than that of the character image data, the flicker suppression process and the moving image blur improvement process can be performed simultaneously in the same screen using the difference value as a determination criterion.

  The configuration and operation of the image display device 100 and the image processing device 200 according to Embodiment 1 of the present invention have been described above.

  According to the image processing apparatus of Embodiment 1 of the present invention, the value of the first pixel at the second time is adjusted so that the value of the first pixel at the second time approaches the value of the first pixel at the first time. Alternatively, the value of the first pixel at the second time can be adjusted such that the value of the first pixel at the second time moves away from the value of the first pixel at the first time. As a result, the flicker of the image caused by the value of the first pixel at the second time being different from the value of the first pixel at the first time, and the value of the first pixel at the second time are the first time. The afterimage of the image caused by being close to the value of the first pixel in can be reduced.

  In the example shown in FIG. 1, the image display device 100 corresponds to “image display device”, and the image display unit 5 corresponds to “display means for displaying an image including a first pixel having an adjusted value”. The image processing apparatus 200 corresponds to the “image processing apparatus”, and the frame memory 1 and the differentiator 2 are “the first pixel included in the image, and follow the value of the first pixel at the first time and the first time. Corresponding to the “calculation means for obtaining the first difference with the value of the first pixel at the second time”, the image characteristic determination unit 6 displays “at least one of which the magnitude of the first difference indicates the reference magnitude of the first difference” Corresponding to the “first determination means for determining whether or not it is greater than at least one of the first reference values”, the filter circuit 3 and the computing unit 4 are set to “second time based on the determination result of the first determination means”. The value of the first pixel at is the value of the first pixel at the first time The value of the first pixel at the second time is adjusted so that the value of the first pixel at the second time moves away from the value of the first pixel at the first time. Corresponds to the “adjustment means for adjusting”.

  However, the image display device 100 and the image processing device 200 according to Embodiment 1 of the present invention are not limited to those shown in FIG. As long as the functions of the respective means described above are achieved, an apparatus having any configuration can be included in the scope of the present invention. Other examples of the image display apparatus 100 and other examples of the image processing apparatus 200 will be described in detail later.

  For example, each unit described in the first embodiment shown in FIG. 1 may be realized by hardware, may be realized by software, or may be realized by hardware and software. Regardless of whether it is realized by hardware, software, or hardware and software, the image processing apparatus 200 determines that “the first pixel included in the image has the first time. And “the step of obtaining the first difference between the value of the first pixel at the second time following the first time and the value of the first pixel at the first time” and “the first difference indicates the reference size of the first difference” “Determining whether or not at least one of at least one first reference value is larger” and “Based on the determination result of the determining step, the value of the first pixel at the second time is determined at the first time. Adjust the value of the first pixel at the second time to approach the value of the first pixel, or move the value of the first pixel at the second time away from the value of the first pixel at the first time The image processing of the present invention and a step "to adjust the value of the first pixel in the second time may be performed as. The image processing of the present invention may have an arbitrary procedure as long as each step described above can be executed.

  For example, the image processing apparatus 200 according to the first embodiment of the present invention stores an image processing program for causing the functions of the image processing apparatus 200 to be executed.

  The image processing program may be stored in advance in a storage unit included in the image processing apparatus 200 when the image processing apparatus 200 is shipped. Alternatively, the image processing program may be stored in the storage unit after the image processing apparatus 200 is shipped. For example, the user may download an image processing program from a specific website on the Internet for a fee or free of charge, and install the downloaded program in the image processing apparatus 200. When the image processing program is recorded on a computer-readable recording medium such as a flexible disk, CD-ROM, or DVD-ROM, the image processing is performed using the input device (for example, a disk drive device). You may make it install in. The installed image processing program is stored in the storage means.

  Hereinafter, other examples of the image display device 100 and other examples of the image processing device 200 will be described in detail in “2. Embodiment 2” and “3. Embodiment 3” with reference to the drawings.

2. Embodiment 2
In the second embodiment, the difference image data is obtained as the output Δ of the differencer 2, and an example in which moving image blur and flicker removal are simultaneously achieved based on this difference image data will be described.

  FIG. 6 shows a configuration of the image display apparatus 300 according to the second embodiment of the present invention. In FIG. 6, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  The image display device 300 includes an image processing device 400 and an image display unit 5. An image processing apparatus 400 includes a frame memory 1 that stores data representing an image, a differentiator 2 that generates a difference image, a filter circuit 3, an arithmetic unit 4 that adds or subtracts a plurality of data, and a table converter. 8 and so on. The filter circuit 3 includes an inverter 31 and an amplifier 32.

  The table converter 8 can obtain the inversion information and the amplification degree α by table conversion with reference to the output Δ of the differentiator 2.

  The filter circuit 3 processes the input image data in accordance with the outputs of the table converter 8 and the differentiator 2 and outputs it.

Assume that the output Δ from the differentiator changes from +1 to −1. The table converter 8 is, for example,
If input Δ is 1> = Δ> = 0.9, α = 0.5 and no inverted signal,
If 0.9>Δ> 0.8, α = 0.2 and there is an inverted signal,
If 0.8> = Δ> = − 0.8, α = 1.0 and there is an inverted signal
If −0.8>Δ> −0.9, α = 0.2 and there is an inverted signal,
If −0.9> = Δ> = − 1, data conversion is performed with a combination of α = 0.5 and no inverted signal, and the amplification degree α and the inverted information are output to the amplifier 32 and the inverter 31. In this case, when there is no inversion signal and α = 0.5, the difference image data Δ has a low-pass transmission type characteristic (see FIG. 3C), and a flicker prevention effect is obtained. Further, when there is an inverted signal, the difference image data Δ has a high frequency emphasis B characteristic (see FIG. 3E), and an effect of improving moving image blur can be obtained.

  The relationship between the difference image data Δ and α in the table conversion is not limited to the above, but may be any relationship. However, when the difference image data Δ is 1 or near −1, 0 <α <1 and no inverted signal combination. By using this, a low-pass transmission type signal is obtained, and a flicker prevention effect is obtained. When the difference image data Δ is not in the vicinity of +1 and −1, table conversion satisfying the combination of α and the inverted signal may be performed so that the relationship between the inverter and the amplification degree shown in FIG.

  The table conversion defines the output for the input. In the above table conversion example where the input and output are nonlinear, the input is input in a digital memory such as a ROM (Read Only Memory) and a RAM (Random Access Memory). This can be easily achieved by using the address and the output as the converted data value.

3. Embodiment 3
In Embodiment 3, since the output Δ of the differentiator 2 corresponds to the frequency component of the moving image data, the value of the output Δ may be determined according to the magnitude of this frequency component, and the degree of amplification is determined by the differencer 2. The output is determined.

  FIG. 7 shows a configuration of an image display apparatus 500 according to the third embodiment of the present invention. In FIG. 7, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  The image display device 500 includes an image processing device 600 and an image display unit 5. The image processing apparatus 600 includes a frame memory 1 that stores data indicating an image, a differentiator 2 that generates a difference image, and a filter circuit 3. The filter circuit 3 includes a table converter 7.

  The table converter 7 converts and outputs it according to the output of the differentiator 2. The input image data is processed and output according to the output of the filter circuit 3.

  Hereinafter, the white data indicating the white of the image is normalized to 1 and the black data indicating the black of the image is normalized to 0 to indicate the white data and the black data. Since the output from the differentiator 2 of the input image indicates a change from white to black as 1 and a change from black to white as −1, the difference image data Δ changes between +1 and −1. The magnitude of the difference image data Δ is indicated by absolute value data.

  In a monochrome character image portion or a wire frame binary image portion portion where flicker is likely to occur, the table converter 7 sets the absolute value of the output Δ from the differentiator 2 to 1 and sets α to 0 <α <1 ( For example, when | Δ | = 1 and α = 0.5), the low-pass transmission type is used. As the absolute value of the output Δ from the differentiator 2 decreases, α becomes α <0 (for example, | Δ | = 0.1 and α = -1) and high frequency emphasis.

  FIG. 8 shows a conversion curve of the table converter 7. The conversion curve shows the relationship between input and output. The horizontal axis shows the output of the differencer 2, and the vertical axis shows the output after conversion.

  When the output of the differentiator 2 is 1, the output of the table converter 7 is 0.5 times the input to the table converter 7 and the output Δ is added to the current image data. In this case, the amplification degree α corresponds to 1. That is, in an image with a large output of the differentiator 2 (binary is an image or a wire frame image), the output to the image display unit 5 is a low-pass transmission type signal, and flicker can be reduced.

  When the output of the differentiator 2 is 0.5, the output of the table converter 7 is multiplied by -0.5 times the input to the table converter 7. This conversion is equivalent to setting the amplification degree α to −1. By adding the output to the current image data, the output to the image display unit 5 becomes a high-frequency emphasized image, and the motion blur is improved.

  Points other than the representative points are also converted according to the conversion table of FIG.

  FIG. 9 shows the relationship between the representative value (input value and output value) of the conversion table (see FIG. 8), the degree of amplification α, and the characteristics. The conversion table includes, for example, a table that emphasizes high-frequency emphasis and suppresses low-frequency transmission characteristics, and a table that emphasizes low-frequency transmission characteristics. The conversion table has a non-linear relationship and is stored in the digital memory.

  The curve indicating the relationship between the output and the input can be determined according to the characteristics of the image or the characteristics of the image display. For example, if the difference value is large, it can be a low-frequency transmission signal, and if the difference value is small, it can be a high-frequency emphasis signal.

  According to the image display device 500 of Embodiment 3 of the present invention, it is possible to simultaneously remove moving image blur and flicker by simply performing table conversion according to the difference information of a moving image.

  The conversion table is not limited to being fixed. The value indicated by the table may be rewritten based on the difference image data output from the image characteristic determiner provided outside the image display device 500.

  In the third embodiment of the present invention, the case where the difference image data Δ can be obtained by subtracting the data (f−1) indicating the image one frame before from the data (f) indicating the current image is shown. On the other hand, it may be obtained by subtracting data (f) indicating the current image from data (f-1) indicating the image one frame before.

  As described above, the present invention has been illustrated using the preferred embodiment of the present invention with reference to FIGS. 1 to 9, but the present invention should not be construed as being limited to this embodiment. . It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range based on the description of the present invention and the common general technical knowledge from the description of specific preferred embodiments of the present invention. Patents, patent applications, and documents cited herein should be incorporated by reference in their entirety, as if the contents themselves were specifically described herein. Understood.

  According to the image processing device, the program, the recording medium, and the image display device of the present invention, the value of the first pixel at the second time is such that the value of the first pixel at the second time approaches the value of the first pixel at the first time. The value can be adjusted, or the value of the first pixel at the second time can be adjusted such that the value of the first pixel at the second time moves away from the value of the first pixel at the first time. As a result, the flicker of the image caused by the value of the first pixel at the second time being different from the value of the first pixel at the first time, and the value of the first pixel at the second time are the first time. The afterimage of the image caused by being close to the value of the first pixel in can be reduced.

It is a figure which shows the structure of the image display apparatus 100 of Embodiment 1 of this invention. It is a figure for demonstrating the principle of this invention. It is a figure which shows the relationship between amplification information (alpha) and difference image data (DELTA). It is a figure which shows the relationship between inversion information, amplification degree, the kind of calculating part, and an image characteristic. 3 is a diagram illustrating a configuration of an image characteristic determination unit 6. FIG. It is a figure which shows the structure of the image display apparatus 300 of Embodiment 2 of this invention. It is a figure which shows the structure of the image display apparatus 500 of Embodiment 3 of this invention. It is a figure which shows the conversion curve of the table converter. It is a figure which shows the relationship between the typical value (input value and output value) of a conversion table (refer FIG. 8), amplification degree (alpha), and a characteristic.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Frame memory 2 Difference machine 3 Filter circuit 4 Operation unit 5 Image display part 6 Image characteristic determination part 31 Inverter 32 Amplifier 100 Image display apparatus 200 Image processing apparatus

Claims (13)

An arithmetic means for obtaining a first difference between a value of the first pixel at a first time and a value of the first pixel at a second time following the first time, the first pixel being included in the image;
First determination means for determining whether the magnitude of the first difference is greater than at least one of at least one first reference value indicating a reference magnitude of the first difference;
Based on the determination result of the first determination means, the value of the first pixel at the second time so that the value of the first pixel at the second time approaches the value of the first pixel at the first time. Or adjusting means for adjusting the value of the first pixel at the second time so that the value of the first pixel at the second time moves away from the value of the first pixel at the first time. An image processing apparatus comprising:   The first determination unit determines whether or not a magnitude of a high-frequency component in the first pixel calculated by the calculation unit as the first difference is greater than at least one of at least one reference value. Item 8. The image processing apparatus according to Item 1. The adjusting means generates inversion information indicating whether to invert the sign of the first difference based on the first difference, and coefficient information indicating an amplification coefficient for the first difference,
The adjusting means determines an adjustment amount of the value of the first pixel at the second time based on the generated inversion information and the generated coefficient information;
The image processing apparatus according to claim 1, wherein the adjustment unit adjusts the value of the first pixel at the second time by the determined adjustment amount. The image processing apparatus further includes first storage means for storing at least one table,
The at least one table represents a correspondence relationship between inversion information and the magnitude of the first difference and a correspondence relation between coefficient information and the magnitude of the first difference,
The image processing apparatus according to claim 1, wherein the inversion information indicates whether to invert the sign of the first difference, and the coefficient information indicates an amplification coefficient for the first difference.   The image processing apparatus according to claim 4, wherein each of the inversion information and the coefficient information is associated non-linearly with respect to the first difference.   The image processing apparatus according to claim 4, wherein the first storage unit includes a digital memory. The adjustment amount of the value of the first pixel at the second time is associated with the first difference,
The image processing apparatus according to claim 1, wherein the adjustment unit adjusts the value of the first pixel at the second time by an adjustment amount corresponding to the calculated first difference.   The image processing apparatus according to claim 7, wherein the adjustment amount of the value of the first pixel at the second time is associated non-linearly with respect to the first difference. The image processing apparatus further includes second storage means for storing information indicating the adjustment amount,
The image processing apparatus according to claim 7, wherein the second storage unit includes a digital memory. The calculation means is a second pixel included in the image, and further calculates a second difference between the value of the second pixel at the first time and the value of the second pixel at the second time,
The second pixel is different from the first pixel;
The first determination means determines whether the magnitude of the second difference is greater than the at least one of at least one second reference value indicating a reference magnitude of the second difference. A determination means,
2. The image according to claim 1, wherein the adjustment unit adjusts the value of the one pixel at the second time and the value of the two pixels at the second time based on a determination result of the second determination unit. Processing equipment. A program for causing a computer to execute image processing,
The image processing is
(A) calculating a first difference between a value of the first pixel at a first time and a value of the first pixel at a second time following the first time, the first pixel being included in the image;
(B) determining whether the magnitude of the first difference is greater than at least one of at least one first reference value indicating a reference magnitude of the first difference;
(C) based on the determination result of the step (b), the first pixel at the second time so that the value of the first pixel at the second time approaches the value of the first pixel at the first time. Adjust the value of the pixel, or adjust the value of the first pixel at the second time so that the value of the first pixel at the second time moves away from the value of the first pixel at the first time A program that includes steps. A computer-readable recording medium recording a program for causing a computer to execute image processing,
The image processing is
(A) calculating a first difference between a value of the first pixel at a first time and a value of the first pixel at a second time following the first time, the first pixel being included in the image;
(B) determining whether the magnitude of the first difference is greater than at least one of at least one first reference value indicating a reference magnitude of the first difference;
(C) based on the determination result of the step (b), the first pixel at the second time so that the value of the first pixel at the second time approaches the value of the first pixel at the first time. Adjust the value of the pixel, or adjust the value of the first pixel at the second time so that the value of the first pixel at the second time moves away from the value of the first pixel at the first time A recording medium including steps. An image processing apparatus according to claim 1;
An image display device comprising: display means for displaying the image including the first pixel having the adjusted value.

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