JP2003050560A - Image processing system, image display device, program, and information storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing system which can appropriately prevent a movement blur when edge-emphasis processing is performed, and to provide an image display device, a program, and an information storage medium. SOLUTION: An image processing part is provided with a movement detection part 20 which detects the movement of a plurality of specific object pixels constituting an image, an arithmetic part 40 which finds the variance value of moving vectors of the object pixels according to information showing the movement of the object pixels grasped by the movement detection part 20, a decision part 60 which decides whether the variance value found by the movement arithmetic part 40 is less than a specific value, and an edge emphasis processing part 70 which performs the edge emphasis processing with larger edge intensity when the decision processing result is true than when false.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing system, an image display device, a program and an information storage medium used for edge enhancement processing.

[0002]

2. Description of the Related Art In a so-called hold type display such as a liquid crystal display device, the display light in each field is maintained at a substantially constant brightness for one field.

However, due to the display method peculiar to the hold type, a person watching the moving image at the time of displaying a moving image feels a so-called blur.

To solve such a problem, for example, Japanese Patent Application Laid-Open No. 7-199856 proposes a method of edge enhancing the spatial frequency of a moving element in an image according to the speed of the element.

However, when the edge enhancement processing is performed by such a method, the degree of edge enhancement is locally changed according to the moving speed, so that the boundary between the image areas having different moving speeds, especially the moving image area is changed. The boundary between the image area and the image area that does not appear looks unnatural.

The present invention has been made in view of the above problems, and an object thereof is an image processing system capable of appropriately preventing motion blur when edge enhancement processing is performed,
An object is to provide an image display device, a program, and an information storage medium.

[0007]

In order to solve the above problems, an image processing system according to the present invention, in an image processing system for hold type image display, grasps the movement of a plurality of predetermined target pixels forming an image. And a movement grasping means
Motion calculating means for obtaining a variance value of the motion vector of the target pixel based on the information indicating the movement of the target pixel grasped by the motion grasping means, and the variance value obtained by the motion computing means is less than a predetermined value. Relative to the determination means for performing the first determination processing for determining whether the first determination processing result is true, the edge strength relative to the case where the first determination processing result is false. Edge enhancement processing means for enhancing the edge to the entire image
It is characterized by including.

An image display device according to the present invention is characterized by including the image processing system.

Further, the program according to the present invention is a program for displaying a hold type image, which is a computer readable program, and is a motion grasping means for grasping the motion of a plurality of predetermined target pixels forming an image. And a motion calculation means for calculating a variance value of the motion vector of the target pixel based on the information indicating the motion of the target pixel recognized by the motion recognition means, and the variance value calculated by the motion calculation means is predetermined. A determination unit that performs a first determination process for determining whether the value is less than a value, and an edge strength when the first determination process result is true as compared with a case where the first determination process result is false. It is characterized in that the computer is made to function as an edge enhancement processing means for relatively enhancing the edge of the entire image.

An information storage medium according to the present invention is an information storage medium usable by a computer, and is characterized by storing a program for causing the computer to function as the above means.

According to the present invention, when the variance value of the motion vector of the target pixel is small, the edge enhancement processing is performed so that the edge enhancement is performed only when a plurality of pixels forming an image are uniformly moving. Processing can be performed.

By performing edge enhancement processing with high edge strength on the entire image only when a plurality of pixels are moving uniformly, the boundary between the moving area and the non-moving area becomes unnatural. Since the occurrence of the situation can be prevented, the motion blur can be appropriately prevented.

Further, the image processing system according to the present invention is
In an image processing system for hold-type image display, a motion grasping unit that grasps movements of a plurality of predetermined target pixels that form an image, and a value indicating a movement amount of the target pixel that is grasped by the motion grasping unit, A predetermined range of motion calculation means for obtaining a value indicating the movement direction of the target pixel, a difference between values indicating the movement amounts of the plurality of target pixels, and a difference between values indicating the movement directions of the plurality of target pixels. Determination means for performing a first determination process for determining whether or not the edge strength is higher than that in the case where the first determination process result is true as compared with the case where the first determination process result is false. And edge enhancement processing means for relatively enhancing the edge of the entire image to enhance the edge of the entire image.

An image display device according to the present invention is characterized by including the image processing system.

Further, the program according to the present invention is a program for displaying a hold type image, which is a computer readable program, and is a motion grasping means for grasping the motion of a plurality of predetermined target pixels forming an image. A motion calculation means for obtaining a value indicating the motion amount of the target pixel grasped by the motion grasping means and a value indicating the movement direction of the target pixel, and a value indicating the motion amount of the plurality of target pixels. Determination means for performing a first determination processing for determining whether or not the difference and the difference between the values indicating the movement directions of the plurality of target pixels are within a predetermined range; and the first determination processing result is true. In some cases, the computer functions as an edge enhancement processing unit that relatively enhances the edge strength as compared with the case where the first determination processing result is false and performs edge enhancement on the entire image. And characterized in that.

An information storage medium according to the present invention is an information storage medium usable by a computer, and is characterized by storing a program for causing a computer to function as the above means.

According to the present invention, when a plurality of target pixels have substantially the same movement direction and magnitude, the edge enhancement processing is performed so that the plurality of pixels forming the image are uniformly moving. Only in this case, the edge enhancement processing can be performed.

By performing edge enhancement processing with high edge strength on the entire image only when a plurality of pixels move uniformly, the boundary between the moving area and the non-moving area becomes unnatural. Since the occurrence of the situation can be prevented, the motion blur can be appropriately prevented.

In the image processing system and the image display device, the brightness detecting means for detecting the brightness of the neighboring pixels of the target pixel, and the average and variance values of the brightness of the neighboring pixels detected by the brightness detecting means. A luminance calculation means for each of the target pixels, the determination means, the average value of the luminance for each of the target pixels obtained by the luminance calculation means is less than a predetermined value, and for each of the target pixels A second determination process is performed to determine whether the variance value of brightness is equal to or greater than a predetermined value, and the edge enhancement processing unit determines that the first determination process result is true, and the second determination process result is If it is true, the edge strength is relatively increased compared with the case where the first determination processing result is false or the second determination processing result is false, and Eh Emphasize may be carried out.

Further, the program (or the information storage medium) includes a brightness detecting means for detecting the brightness of the neighboring pixels of the target pixel, and an average value and a variance value of the brightness of the neighboring pixels detected by the brightness detecting means. By causing a computer to function as a brightness calculation unit for each target pixel (or storing a program for causing the computer to function), and the determination unit to determine the brightness of each target pixel calculated by the brightness calculation unit. A second determination process is performed to determine whether the average value is less than a predetermined value, and the variance value of the brightness of each target pixel is a predetermined value or more, and the edge enhancement processing unit determines that the first determination process result is True and the second determination processing result is true, the first determination processing result is false, or the second determination processing is Results may perform edge enhancement for the entire image relatively increased edge strength as compared with the case where the false.

According to this, when the average value of the luminance around the target pixel is large and the variance value is small, it is possible to perform the processing that does not perform the edge enhancement processing. As a result, it is possible to prevent erroneous edge enhancement even when there is no motion in an image with uniform brightness in which the motion vector detection accuracy decreases.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to the drawings, taking as an example the case where the present invention is applied to an image processing system using a liquid crystal projector which is a kind of image display device. The embodiments described below do not limit the content of the invention described in the claims. Further, not all of the configurations shown in the following embodiments are indispensable as means for solving the invention described in the claims.

(Description of Entire System) Image processing in the case where the present invention is applied to an image processing unit of a liquid crystal projector which performs hold type image display in order to appropriately prevent motion blur when edge enhancement processing is performed. The functional blocks of the unit will be described.

The hold-type image display means (1) each display unit (pixel) holds each image signal (luminance signal) for one field (or one frame) period,
Light is emitted or modulated based on the held image signal (luminance signal), or (2) one display unit (pixel) has the same image signal (luminance) for at least one field (or one frame) period. It means that light is emitted or modulated based on a signal).

FIG. 1 is a functional block diagram of an image processing unit in a liquid crystal projector according to an example of this embodiment.

The image processing unit includes an image data input unit 10 for inputting image data for one frame, and a motion detecting unit functioning as a motion grasping unit for grasping movements of a plurality of predetermined target pixels in the input image data. 20 and a motion calculation unit 40 that obtains the variance value of the motion vector of the target pixel based on the information indicating the motion of the target pixel that is grasped by the motion detection unit 20.

Further, the image processing unit is the image data input unit 1
Based on the image data from 0, the brightness detection unit 30 that detects the brightness of the neighboring pixels of the target pixel, and the average value and the variance value of the brightness of the neighboring pixels detected by the brightness detection unit 30 are
The brightness calculation unit 50 is obtained for each of a plurality of predetermined target pixels forming an image.

Further, the image processing unit determines the first determination process for determining whether the variance value calculated by the motion calculation unit 40 is less than a predetermined value and the average value of the brightness calculated by the brightness calculation unit 50 is a predetermined value. A determination unit 60 that performs a second determination process that determines whether the variance value that is less than the value and that is calculated by the brightness calculation unit 50 is equal to or greater than a predetermined value, and the first and second determination process results by the determination unit 60. In the case of true, the edge enhancement processing unit 70 that relatively enhances the edge strength as compared with the case of false and performs edge enhancement on the entire image, and the image data output unit that outputs the image data after the edge enhancement processing. And 80.

As described above, when the variance value of the motion vector of the target pixel is small, the edge enhancement processing with high edge strength is performed, so that only when a plurality of pixels forming the image move uniformly. Edge enhancement processing with high edge strength can be performed.

In this way, the boundary between the moving region and the non-moving region becomes unnatural by performing the edge enhancement processing with high edge strength only when a plurality of pixels move uniformly. Since it is possible to prevent the occurrence of blur, it is possible to appropriately prevent the motion blur.

Further, when the average value of the luminance around the target pixel is large and the variance value is small, the edge enhancement processing is not performed or the very weak edge enhancement processing is performed. As a result, it is possible to prevent erroneous normal edge enhancement from being performed in an image with uniform luminance where the motion vector detection accuracy is degraded, even if there is no motion.

Here, the above-mentioned target pixel will be described.

FIG. 2 is a schematic diagram showing target pixels in an image.

For example, as shown in FIG. 2, 12 target pixels are set uniformly in one image.

The motion detector 20 detects the motion vectors in the x and y directions of these 12 target pixels.
As a motion vector detection method, for example, a block pattern matching method or the like can be used.

The brightness detecting section 30 detects the average brightness of the target pixel and its surroundings.

(Explanation of Processing Flow) Next, the flow of image processing using the above-mentioned respective parts will be explained.

FIG. 3 is a flow chart showing the flow of image processing according to an example of this embodiment.

First, the image data input unit 10 inputs image data for one frame. Then, the motion detector 20
Is based on the image data from the image data input unit 10,
The x-direction and y-direction motion vectors of the plurality of target pixels shown in FIG. 2 are detected (step S2).

The brightness detecting section 30 detects the average brightness of the target pixel and its neighboring pixels based on the image data from the image data input section 10 (step S4).

Then, the motion calculating section 40 is connected to the motion detecting section 2
The variance value of the motion vector in the x direction and the motion vector in the y direction obtained by 0 is calculated. Further, the brightness calculation section 50 calculates the variance value of the average brightness calculated by the image data input section 10.

Then, the judging section 60 judges whether the variance value of the motion vector in the x direction is small (whether it is less than a predetermined value) based on the calculation result of the motion calculating section 40 (step S6). It is determined whether the variance value of the motion vector is small (is less than a predetermined value) (step S
8), the first determination process is performed.

If the result of the first determination processing is true, the determination unit 60 further determines whether the average brightness value by the brightness calculation unit 50 is small (less than a predetermined value) and the variance value is large (greater than or equal to a predetermined value). ) It is determined whether the second determination process is performed (step S10).

If the result of the second determination processing is also true, the edge enhancement processing unit 70 increases the gain during the edge enhancement processing so that edge enhancement with high edge strength is performed on the entire image. Perform processing (step S1)
2).

It should be noted that it is determined whether the variance value of the motion vector in the x direction is small (step S6), and whether the variance value of the motion vector in the y direction is small (step S6).
8) If the average luminance value is small and the result of the determination as to whether the variance value is large (step S10) is false, the edge emphasis processing unit 70 determines the gain during the edge emphasis processing. Is lowered, and edge enhancement processing is performed so that edge enhancement with low edge strength is performed on the entire image (step S14).

Then, the image data output section 80 outputs the image data after the image processing by the edge enhancement processing section 70. This controls the liquid crystal light valve,
The liquid crystal projector projects and displays an image.

As a result, an image having a high edge strength, that is, an edge in which the edge is emphasized is projected and displayed only when the edge emphasis processing should be performed.

As described above, according to the present embodiment, the edge enhancement processing with a high edge strength is performed only when the plurality of pixels forming the image are uniformly moved, so that the moving area and the moving area are moved. Since it is possible to prevent the occurrence of a situation in which the boundary with the unfilled area becomes unnatural, it is possible to appropriately prevent motion blur.

Further, when the average value of the luminance around the target pixel is large and the variance value is small, the edge enhancement processing is not performed or the edge enhancement having a weaker intensity than usual is performed. As a result, it is possible to prevent erroneous normal edge enhancement from being performed in an image with uniform luminance where the motion vector detection accuracy is degraded, even if there is no motion. (Description of Hardware) Next, a block diagram of hardware of an image processing unit in the liquid crystal projector will be described.

FIG. 4 is a block diagram of the hardware of the image processing unit in the liquid crystal projector according to the example of this embodiment.

In the apparatus shown in FIG. 4, the CPU 1000, R
OM1002, RAM1004, information storage medium 100
6, image generation IC 1010, I / O (input / output port) 1
020 is connected by a system bus 1016 so that data can be transmitted and received between them. Then, it is connected to a device such as a PC via the I / O 1020.

The functions of the image data input unit 10 and the image data output unit 80 shown in FIG.
Can be implemented by using the motion detection unit 20, the brightness detection unit 30,
The functions of the motion calculation unit 40, the brightness calculation unit 50, the determination unit 60, and the edge enhancement processing unit 70 are, for example, the CPU 1000.
And image generation IC 1010 and RAM 1004.

The functions of the motion detecting section 20, the determining section 60 and the like can be realized by causing the computer to read the program from the information storage medium 1006.

The information storage medium 1006 is, for example, a CD-ROM, a DVD-ROM, a ROM or a RAM.
Etc. can be applied, and the reading method of the program may be a contact method or a non-contact method.

Further, instead of the information storage medium 1006, it is also possible to realize the above-mentioned functions by downloading a program for realizing the above-mentioned functions from a host device or the like via a transmission path. . That is, the program for realizing the above-described functions may be embodied on a carrier wave.

(Explanation of Modifications) The application of the present invention is not limited to the above-described embodiments, but can be applied to various modifications.

For example, the image processing method is not limited to the above-mentioned method, and various modifications can be made.

For example, instead of the motion detecting section 20 and the motion calculating section 40 using the above-described motion vector, a motion grasping section for grasping the movement of the target pixel and a motion amount of the target pixel grasped by the motion grasping section are shown. A motion calculation unit that determines a value and a value indicating the movement direction of the target pixel, and the determination unit 60 replaces the first determination process described above with a difference between the values indicating the motion amounts of the plurality of target pixels. , And may determine whether or not the difference between the values indicating the movement directions of the plurality of target pixels is within a predetermined range.

Also by this, it is possible to grasp the movement of the target pixel and perform the edge emphasis processing with high edge strength only when the entire image moves uniformly.

Further, the above-mentioned motion detecting section 20 detects the motion vectors in the x direction and the y direction of the plurality of target pixels shown in FIG. 2 based on the image data from the image data input section 10. , X-direction (horizontal direction of image) or only y-direction (vertical direction of image) may be detected.

The above-described second determination processing is not essential, and only the first determination processing may be performed.

In the above-described embodiment, when the first or second determination result is false, the edge emphasis processing with low edge strength is performed. In this case, however, the edge strength is 0, that is, no edge emphasis is performed. Does not have to be performed.

The target pixel shown in FIG. 2 is 1 in one image.
Two pixels were evenly located, but the target pixel was 11
The number of pixels may be equal to or less than 13 or may be equal to or more than 13, and the target pixel does not necessarily have to be an evenly located pixel.

The liquid crystal projector is not the only image display device that can employ the above-mentioned hold type display system. For example, the present invention can be applied to an image processing system having an image display device other than the liquid crystal projector.
As such an image display device, for example, besides a liquid crystal display device such as a direct-view type liquid crystal display device or a liquid crystal display, a display device using an organic EL element, a DMD (Digital
Various image display devices such as a projector using a Micromirror Device are applicable. DMD is a trademark of Texas Instruments Incorporated in the United States. The projector is not limited to the front projection type, but may be the rear projection type.

The function of the image processing unit of the liquid crystal projector described above may be realized by a single image display device (for example, a liquid crystal projector) or may be distributed by a plurality of processing devices (for example, a liquid crystal projector and a liquid crystal projector). PC (Personal Com
distributed processing) with puter).

[Brief description of drawings]

FIG. 1 is a functional block diagram of an image processing unit in a liquid crystal projector according to an example of the present embodiment.

FIG. 2 is a schematic diagram showing target pixels in an image.

FIG. 3 is a flowchart showing a flow of image processing according to an example of the present embodiment.

FIG. 4 is a block diagram of hardware of an image processing unit in the liquid crystal projector according to the example of the present embodiment.

[Explanation of symbols]

20 Motion detector 30 Luminance detector 40 Motion calculator 50 Luminance calculator 60 Judgment section 70 Edge Enhancement Processing Unit 1006 information storage medium

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G06T 5/00 100 G06T 5/00 100 7/00 7/00 T 7/20 7/20 B G09G 3 / 34 G09G 3/34 D 3/36 3/36 F term (reference) 2H093 NA16 NC42 NC51 NC56 NC62 NC65 ND07 ND09 ND10 ND23 5B057 AA20 CA08 CA12 CA16 CB08 CB12 CB16 CC01 CE03 CH01 DA16 DC08 DC16 DC22 5C006 BC16 AF16 EC11 AF46 AF46 AF46 AA10 BB05 DD01 EE19 JJ01 JJ02 JJ07 5L096 AA06 BA20 DA01 FA06 FA14 FA32 FA33 FA67 GA51 MA03

Claims (8)

[Claims] 1. An image processing system for hold-type image display, comprising: a movement grasping means for grasping movements of a plurality of predetermined target pixels forming an image; and a movement of the target pixel grasped by the movement grasping means. Motion calculating means for obtaining a variance value of the motion vector of the target pixel based on the information shown, and determining means for performing a first determining process for determining whether the variance value obtained by the motion calculating means is less than a predetermined value. When the first judgment processing result is true, the edge strength is relatively increased as compared with the case where the first judgment processing result is false, and edge emphasis is performed on the entire image. An image processing system comprising: a processing unit. 2. An image processing system for hold type image display, comprising: a motion grasping means for grasping movements of a plurality of predetermined target pixels forming an image; and a movement amount of the target pixel grasped by the motion grasping means. And a value that indicates the movement direction of the target pixel, a difference between values that indicate the movement amounts of the plurality of target pixels, and a difference between values that indicate the movement directions of the plurality of target pixels. Determination means for performing a first determination process for determining whether and are within a predetermined range; and, if the first determination process result is true, the first determination process result is false. An image processing system comprising: an edge enhancement processing unit that relatively enhances edge strength as compared with, and performs edge enhancement on the entire image. 3. The brightness detection unit according to claim 1, wherein the brightness detection unit detects the brightness of a pixel adjacent to the target pixel, and the average value and the variance value of the brightness of the adjacent pixels detected by the brightness detection unit. A luminance calculation unit that obtains each of the target pixels, and the determination unit has an average value of the luminance of each of the target pixels that is obtained by the luminance calculation unit is less than a predetermined value, and
A second determination process is performed to determine whether or not the variance value of the brightness of each target pixel is equal to or greater than a predetermined value, and the edge enhancement processing means has the first determination process result of true and the second determination process. Is true, the edge strength is relatively increased as compared with the case where the first judgment processing result is false or the case where the second judgment processing result is false. An image processing system characterized by performing edge enhancement on an entire image. 4. An image display device comprising the image processing system according to claim 1. 5. A hold type image display program, a computer readable program, comprising: a movement grasping means for grasping movements of a plurality of predetermined target pixels forming an image, and the movement grasping means. Based on the grasped information indicating the movement of the target pixel, a motion calculation unit that obtains a variance value of the motion vector of the target pixel, and whether the variance value obtained by the motion calculation unit is less than a predetermined value is determined. A determination unit that performs a first determination process; and when the first determination process result is true, the edge strength is relatively increased as compared to when the first determination process result is false, and the entire image A program that causes a computer to function as an edge enhancement processing unit that performs edge enhancement on an edge. 6. A hold type image display program, a computer readable program, comprising: a movement grasping means for grasping movements of a plurality of predetermined target pixels forming an image, and the movement grasping means. A motion calculation unit that obtains a value that indicates the amount of movement of the target pixel that has been grasped and a value that indicates the direction of movement of the target pixel; a difference between values that indicate the amount of motion of the plurality of target pixels; Determination means for performing a first determination processing for determining whether or not the difference between the values indicating the pixel movement direction is within a predetermined range; and the first determination processing result if the first determination processing result is true. Is characterized by causing the computer to function as an edge enhancement processing unit that relatively enhances the edge strength and enhances the edge of the entire image as compared with the case where the determination processing result is false. Beam. 7. The brightness detecting means for detecting the brightness of a pixel adjacent to the target pixel according to claim 5, and an average value and a variance value of the brightness of the adjacent pixel detected by the brightness detecting means. , The computer functions as a brightness calculation unit for each of the target pixels, the determination unit, the average value of the brightness of each of the target pixels obtained by the brightness calculation unit is less than a predetermined value, and
A second determination process is performed to determine whether or not the variance value of the brightness of each target pixel is equal to or greater than a predetermined value, and the edge enhancement processing means has the first determination process result of true and the second determination process. Is true, the edge strength is relatively increased as compared with the case where the first judgment processing result is false or the case where the second judgment processing result is false. A program that performs edge enhancement on the entire image. 8. An information storage medium readable by a computer, wherein the program according to any one of claims 5 to 7 is stored.