KR100588742B1 - Apparatus and method for gaining vision alignment image in video phone - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

The present invention relates to an apparatus for acquiring eye-matching images for video communication, a method thereof, and a computer-readable recording medium having recorded thereon a program for realizing the method.

2. The technical problem to be solved by the invention

The present invention obtains an eye image in advance from an image in which the gaze faces the front and inserts it into an eye position input during video communication so that the gaze faces the front to match the eyes, or at least two cameras are installed symmetrically. To obtain an image and to synthesize the obtained images to match the gaze to the other party, and to provide an apparatus for visual communication, and a computer-readable recording medium having recorded thereon a program for realizing the method. To do so.

3. Summary of Solution to Invention

The present invention, image acquisition means for acquiring each image by checking the signal input from each camera; And image synthesizing means for receiving each of the images obtained from the image acquiring means, fixing one image and moving the other image little by little to find an optimal gaze matched image.

4. Important uses of the invention

The present invention is used in video communication systems and the like.

Line of sight, left and right video, left and right eye video, video insertion

Description

Apparatus and method for acquiring gamut matching for video communication {APPARATUS AND METHOD FOR GAINING VISION ALIGNMENT IMAGE IN VIDEO PHONE}             

1 is a diagram illustrating an embodiment of an apparatus for acquiring eye-matching images for video communication according to the present invention;

2 is a block diagram of an embodiment of an apparatus for acquiring eye-matching images for video communication according to the present invention;

Figure 3 is a flow diagram of an embodiment of a gaze matching image acquisition method by left and right image synthesis according to the present invention.

4 is a block diagram of another embodiment of the apparatus for acquiring gaze coincidence image for image communication according to the present invention;

5 is a flow chart of an embodiment of a method for acquiring gaze coincidence images by left and right eye image insertion according to the present invention;

* Explanation of symbols for the main parts of the drawings

201: left camera 202: right camera

203: first image acquisition unit 204: second image acquisition unit

205: Image synthesizer 206: Compression encoder

207: Video playback unit 208: Display device

209: Compression Restoration Unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for acquiring gaze matching for video communication, and a method thereof and a computer-readable recording medium recording a program for realizing the method. In order to realize a gaze-matched image acquisition device for image communication, and a method and the method for inserting a left-eye image to obtain a gaze-matched image, or synthesizing the images taken symmetrically from the left and right, etc. The present invention relates to a computer-readable recording medium having recorded thereon a program.

In the conventional video telephone or a conference system, there is a problem in that the reality of the conversation is lowered due to the disagreement with the other party.

In order to overcome this problem, the camera should be installed near the center of the screen, but the display screen must be obscured, or a hole must be installed because of a lens.

In some studies, the camera is installed behind a liquid crystal display (LCD) screen, the entire LCD screen is displayed when the display is displayed, and the LCD is taken after the display is made transparent, and the user repeats it more than 30 times per second. The research on the way to make people feel in progress is not yet in practical use, and there is a problem that it is not easy to generalize due to the high cost and complexity of production and work even if it is used.

This will be described in detail below.

Recently, as the communication network has been advanced from voice telephone network to integrated information network (ISDN) or high-speed internet network, video telephony that talks to the other party's face and talks away from the existing voice telephone and video conference using the same Commonly referred to as video telephone devices) devices have been released. However, the conventional video telephone apparatuses have a problem that they do not match the gaze.

Normally, when we talk, we want to talk by looking at the other's eyes or its surroundings, and we get a lot of information from the other's eyes other than the information transmitted by voice. In other words, the state of eye contact with the other party is the clearest transmission of information, and deliberately distracting may be seen as something negative. Such eye-matching is sensitive enough that you can immediately feel a little out of your eyes.

Currently, video phones usually install a camera on top of a display device on which the other's face appears. When A and B make a video call, A appears to face B's screen only by looking at his camera, and B does the same. However, if you keep your eyes on the camera, you will not be able to see the other person's face in detail, which will make your eyes match. However, when you see the other person's face, the face taken by the camera becomes a face looking down, so it does not coincide.

In order to overcome this, the camera should be installed near the center of the screen, but the display screen should be obscured, or a hole must be installed in the lens, resulting in damage to the screen. Recently, some studies have installed a camera behind the LCD screen, displays the entire LCD screen when the display is displayed, and transparently captures the LCD when shooting, and repeats it more than 30 times per second so that the user does not feel it. It is underway but not yet put into practical use.

The present invention has been made to solve the problems described above, the eye gaze is obtained from the image facing the front face in advance to insert it into the eye position input during video communication to match the gaze to face the front It is an object of the present invention to provide an apparatus for acquiring eye-matching images for video communication, a method thereof, and a computer-readable recording medium having recorded thereon a program for realizing the method.

The present invention also provides an apparatus, and a method for realizing the same method, and a method for achieving the same method for the image communication apparatus for acquiring an image by symmetrically installing at least two cameras and synthesizing the acquired images to match the gaze. Another purpose is to provide a computer readable recording medium having recorded thereon.

According to an aspect of the present invention, there is provided a gaze matching image acquisition apparatus for video communication, comprising: image acquisition means for acquiring each image by checking a signal input from each camera; And an image synthesizing means for receiving the respective images obtained from the image acquiring means, fixing one image and moving the other image little by little to find an optimal gaze coincidence image.

In addition, the method of the present invention, in the gaze matching image acquisition method applied to the gaze matching image acquisition apparatus for video communication, the first image of the first predetermined size and the predetermined position with respect to the two images captured by the camera A first step of acquiring a predetermined number of second images having a position movement of a second predetermined size; The first image and each of the predetermined number of second images are combined to obtain a predetermined number of temporary gaze matching images, and to determine whether the temporary gaze matching image having the lowest error is an image obtained from the center of the second image. Determining a second step; A third step of determining the temporary gaze coincidence image as a gaze coincidence image when the temporary gaze coincidence image obtained at the center of the second image has the lowest error as a result of the determination of the second step; And if the temporary gaze coincidence image does not have a minimum error as a result of the determination of the second step, has a minimum error among a predetermined number of temporary gaze coincidence images according to whether there is an image reaching a boundary among a predetermined number of second images. Determining the image as a gaze-matched image or repeatedly performing a process of acquiring a predetermined number of second images having the position shift of the second predetermined size in the first step based on the second image when the image has the lowest error And a fourth step.

In addition, the present invention, the gaze coincidence image acquisition device having a processor, a predetermined movement of the position of the second predetermined size with respect to the two images taken by the camera centered around the first image and the predetermined position of the first predetermined size A first function of acquiring the second image of the number; The first image and each of the predetermined number of second images are combined to obtain a predetermined number of temporary gaze matching images, and to determine whether the temporary gaze matching image having the lowest error is an image obtained from the center of the second image. A second function of judging; A third function of determining the temporary gaze coincidence image as a gaze coincidence image when the temporary gaze coincidence image obtained at the center of the second image has the lowest error as a result of the determination of the second function; And as a result of the determination of the second function, if the temporary gaze coincidence image does not have a minimum error, the second gamma image has the lowest error among a predetermined number of temporary gaze coincidence images according to whether there is an image reaching the boundary. Determining the image as a gaze-matched image or repeatedly performing a process of acquiring a predetermined number of second images having a position shift of the second predetermined size of the first function based on the second image when the image has the lowest error A computer readable recording medium having recorded thereon a program for realizing the fourth function is provided.

According to an aspect of the present invention, there is provided an apparatus for acquiring eye-matching images for video communication, comprising: eye image extracting means for extracting an eye image of a user whose eye is facing from a camera; Storage means for storing an eye image in front of the gaze obtained by the eye image extracting means; Image acquisition means for acquiring an image of the user during video communication; And image synthesizing means for inserting an eye image in front of the gaze stored in the storage means into an image acquired by the image acquiring means.

In addition, the method of the present invention includes a gaze matching image acquisition method applied to a gaze matching image acquisition apparatus for video communication, comprising: a first step of obtaining and storing an eye image to be used as a gaze matching image from a user; A second step of finding an insertion position through pattern matching in an image obtained from the user during video communication to insert a stored eye image; And a third step of acquiring the gaze coincidence image by inserting the stored eye image into the found position.

The present invention also provides a gaze matching image acquisition apparatus having a processor, comprising: a first function of acquiring and storing an eye image to be used as a gaze matching image from a user; A second function of finding an insertion position through pattern matching in an image obtained from the user during video communication to insert a stored eye image; And a computer-readable recording medium having recorded thereon a program for realizing a third function of acquiring a gaze-matched image by inserting a stored eye image into a found position.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, an apparatus and method for synthesizing an image by acquiring a symmetrical image using at least two cameras such as left and right image synthesis will be described. The embodiment of the present invention uses a camera installed on the left and right sides of the screen, but the present invention is not limited to the left and right sides of the screen. However, at least two cameras may be used to obtain a face image of a user using a videophone. none.

1 is a diagram illustrating an embodiment of an apparatus for acquiring eye-matching images for video communication according to the present invention.

The video telephony main body has a display device, and two cameras are installed on both sides thereof.

2 is a block diagram of an embodiment of an apparatus for acquiring eye-matching images for video communication according to the present invention.

FIG. 2 illustrates a configuration of a line of sight video call including a line of sight matching device according to the present invention. The left camera 201, the right camera 202, the first image acquisition unit 203, the second image acquisition unit 204, the image synthesis unit 205, the compression encoder 206, and the image reproduction unit 207. ), A display device 208 and a compression restorer 209.

The video telephone main body has a display device 208, and two cameras 201 and 202 are provided on both sides thereof. The image acquisition units 203 and 204 convert analog video signals into digital data of appropriate standards. The image synthesis unit 205 receives the left and right images obtained as the main contents of the present invention, and synthesizes them for gaze matching. The compression encoder 206 performs H-261 (H-261) and MPEG-1 (MPEG-). 1), MPEG-2 (MPEG-2) or an equivalent encoding apparatus. The decompression unit 209 is a device that receives data compressed according to the compression standard and restores the digital image data, and the image reproducing unit 207 converts the digital image data into the display device 208. Images obtained from two cameras are synthesized by the image synthesizer 205 and then compressed and transmitted.

The received data containing the counterpart image is restored in the compressed state and then goes to the display device 208 via the image reproducing unit 207.

If the user wants to check his / her synthesized video, it can be played back through the video player 207.

A process of synthesizing the gaze coincidence image from the left and right images made by the image synthesizer 205 will now be described.

The two images from the left and right cameras are usually very similar because the human face is symmetrical and the face is some distance away from the camera. However, because the viewing angles are different for the minute part, the difference occurs naturally.

The image to be obtained may be an intermediate image (CI) that is not biased to the left image (LI) and is not biased to the right image (RI). This CI is obtained by adding RI and LI. However, the positions of the faces of RI and LI are not exactly the same. This is because the face may not be exactly centered, or the angle of the face may be left or right. When this error is called a face position error (FPD), the maximum value of the FPD is defined as FPDmax. If the size of the image to be transmitted is H pixels horizontally and V pixels vertically, an additional FPDmax pixel is obtained when the image is acquired by the camera. If it is H 'and V', H 'and V' are obtained as shown in [Equation 1].

H '= h + 2FPDmax,

V '= V + 2FPDmax

Obtain CI from two images of LI and RI. The process is as follows.

In LI, you get H- and V-size images. In RI, (-1, -1), (0, -1), (1, -1), (-1,0), (0,0), (1,0), (-1 A total of nine images having horizontal H and vertical V sizes are obtained at positions moved by, 1), (0,1) and (1,1).

CI is created by adding LI and RI, as just described, from horizontal 1 to +1 and vertical 1 to +1. Therefore, a total of nine CIs are obtained. When the horizontal and vertical pixel positions of the nine RIs and CIs are RI _i (x, y) and CI _I (x, y), _I is the index of the image obtained by shifting, and x and y are the horizontal and vertical positions. Indicates a value. At this time, calculate the following error value between CI, LI, RI.

SE (m, n) = SUM (x = 0 to H-1) SUM (y = 0 to V-1) (CI _I (x, y) -LI (x, y))

+ SUM (x = 0 to H-1) SUM (y = 0 to V-1) (CI _I (x, y) -RI _I (x + m, y + n))

Here, SUM (x = 0 to N) means adding all of the following equations while increasing x from 0 to N. m and n are horizontal and vertical displacement values, and have values of -1, 0, and 1 when the RI _I image is obtained. The minimum value of m (m _min ) and n minimum value (n _min ) are obtained as shown in Equation 3 below.

If the horizontal and vertical position shift values (m _min and n _min ) having the lowest error obtained are both 0, the position is taken as the position where the optimal CI is obtained. If it is not 0, move the value from the center of RI, and then use this as the center of the new RI to get 9 images as above and get the new minimum SE _I (m, n), I = 0 ~ 8. Serve This process is continued until the boundary of the obtained RI _I reaches FPDmax, which is the boundary of the RI image, and when the boundary is reached, (m _min , n _min ) is obtained from the position and the CIi (x, y) image at that position is optimal. We do with eyes-matched picture

3 is a flowchart illustrating a gaze matching image acquisition method by left and right image synthesis according to the present invention.

The method of acquiring gaze matching images according to the present invention is a method of obtaining images in which a gaze is directed toward the center by arranging left and right with two cameras for video matching in a videophone, and obtaining respective images. In order to obtain an eye-matching image, one image is fixed and the other image is moved a little while finding the optimum position by the above Equation 2 and Equation 3, and moving to that position again and repeating the above process. You will find a more optimal location.

This will be described according to the flow shown in the drawings.

First, LI and RI are obtained in consideration of FPDmax (301). Around the center of the LI to obtain an image of the H, V size (302), obtains the chapter 9 RI _I was changed to the pixel values in the horizontal, vertical to -1 and +1 around the center of the RI (303). At this time, the size of RI _I is H, V like LI.

Each of LI and 9 RI _I is added to obtain 9 CI _I (304). The error value between CI _I , LI, and RI _I is obtained (305), and it is checked whether the position shift value (m _min , n _min ) of the image having the lowest error is 0 in both horizontal and vertical (306). As a result of the check, if the position shift values (m _min , n _min ) of the image having the lowest error are both horizontal and vertical, the CI _I is determined to be an optimal gaze coincidence image (307).

As a result of the check, if the position shift value (m _min , n _min ) of the image having the lowest error is not 0 in both horizontal and vertical, it is checked whether there is an image reaching the boundary of the entire RI among 9 RI _I (308). . As a result of the inspection, if there is no image reaching the boundary, the 9 images with the lowest error are moved to the same value (m _min , n _min ) by moving the center of RI _I to the horizontal and vertical values from -1 to +1. Obtaining 309 and repeating the process 304 of obtaining an error value between CI _I and LI and RI _I.

After a check to see if the image reaches the boundary of the whole RI in Chapter 9 RI _I, if there is a video reaches the boundary then the horizontal is determined as the optimum line of sight matches the image for the error value of the vertical minimum CI _I (307).

Next, an apparatus and method for acquiring a gaze-matched image by acquiring an eye image from an image in which the gaze faces the front in advance and inserting it in an eye position of an image input during a video call so that the gaze faces the front 4 and 5 will be described.

The present invention obtains an eye image from an image in which the line of sight is facing in advance, and then inserts it into the eye position of the image input during the video call so that the line of sight is directed to the front.

4 is a block diagram of another embodiment of the apparatus for acquiring eye-matching images for video communication according to the present invention.

4 illustrates a configuration of a transmitter of a video telephone including an apparatus for acquiring gaze matching images according to the present invention. The transmission unit of the video telephone includes a camera 401, a pupil image extraction unit 402, a recording storage unit 403, an image acquisition unit 404, an image synthesis unit 405, and an image encoding unit 406.

The user of the video telephone proposed in the present invention should input his front eye image before using the telephone. Of course, you don't have to type it every time. To get an eye image of yourself, first press the line of sight acquisition button. Then, the user looks at the camera 401 at a position using a normal videophone. After acquiring the image in that state, move the cursor to the position of the left and right eyes by pressing the button. The eye image extractor 402 for eye-matching stores eye images of left and right sizes of M pixels horizontally and N pixels vertically around the cursor position. The determination of M and N changes depending on the size of the image to be transmitted and the distance between the camera and the user, so that the user can change it through the keypad. This acquires an eye image.

In general, during a video call, the user dials in front of the video phone and presses a line of sight button. The image synthesizing unit 405 for the gaze matching process searches for an image of M X N size obtained in advance through pattern matching in the obtained image. In general, the eye position is located at the top of the center of the entire image, so the search is performed by setting an appropriate area at the top of the center rather than searching the entire image. The search is done for the left and right eyes respectively, and the right eye's horizontal position is more to the right than the left eye's horizontal position to prevent the left and right eyes from changing. That is, the search is performed under the precondition that the horizontal position of the left eye < the horizontal position of the right eye.

Once the position of the left eye has been determined, a task of replacing the previously extracted left eye image with the position is performed. Before the replacement, the brightness change caused by the change of lighting between the left eye image and the input image to be synthesized should be corrected.

The average of the pixels of the size M X N of the left eye position of the input image is obtained, and the extracted left side obtains the average value of the pixels of the image and then replaces the left eye image as shown in Equation 4 below.

CLE (x, y) = LE (x, y) L / K

Here, CLE (x, y) is M X N size as the left eye image to be replaced. LE (x, y) is a pre-extracted left eye image having an M × N size. L is the average brightness of the pixels of the size M X N of the left eye position of the input image, K is the average brightness of the pixels of the left eye image extracted previously. When the brightness correction is completed, replace the CLE (x, y) image at the left eye position of the input image. Subsequently, the substituting interface is subjected to lowpass filtering having a size of 3 X 3 pixels to remove the unobtrusive interface. The right eye is performed in the same way, and when the execution is completed, the right eye is compressed and transmitted by the image encoder 406 which processes image compression and encoding.

This gaze matched image may not be used by the user in some cases, so a switch can be turned off or on.

5 is a flowchart illustrating a method of acquiring gaze coincidence images by inserting left and right eye images according to the present invention.

The present invention, in order to obtain a line-of-sight image in a video phone, etc., the user first looks at the camera and takes a front picture as a still image, where the pupil position is specified to obtain a left eye and right eye image, and then input each video within a video to be transmitted. It is a technology that obtains the eye-matched image by replacing the left eye image and the right eye image by pattern matching between the left eye image and the right eye image. In the process described above, Equation 4 is a technique of correcting the brightness change and performing the two-dimensional low pass filtering on the replaced boundary to eliminate the boundary passing.

This will be described according to the flow shown in the drawings.

First, according to a user's selection, an image in which the gaze faces the front is obtained and stored (501).

In operation 502, a user who initiates a video call is requested to insert a stored video for gaze matching from a user who starts a video call from a video during a video call. In this case, each eye is performed separately, and the priority is selected from the left or the right eye according to the designation. Of course, two images can be inserted at the same time.

The image for gaze matching is positioned at the corresponding position, and brightness correction of the inserted image is performed (504).

The interface is trimmed by low pass filtering so that the inserted image is compatible with the existing image (505), and the image is provided as a gaze matching image.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be apparent to those of ordinary skill in Esau.

As described above, the present invention can obtain an image matched by the left and right eye image insertion or the left and right image synthesis, and prevents the reality of the conversation from falling out of line with the other party in a video telephone or a conference system. There is.

In addition, the present invention has an effect of enabling the use of the video communication service that more people can solve the gaze matching problem by implementing the gaze matching problem in an uncomplicated manner in video communication.

Claims (11)

In the eye-matching image acquisition device for video communication, Image acquisition means for acquiring each image by checking a signal input from each camera; And Image synthesizing means for receiving the respective images obtained from the image acquiring means and fixing one image and moving the other image little by little to find an optimal gaze match image. Gaze matching image acquisition device for video communication comprising a. The method of claim 1, The image acquisition means, First image acquisition means for processing a signal input from a first camera to present an image acquired by the first camera; And Second image acquisition means for presenting an image obtained by the second camera by processing a signal input from a second camera symmetrically positioned in the first camera Gaze matching image acquisition device for video communication comprising a. In the eye-matching image acquisition device for video communication, Eye image extraction means for extracting an eye image of a user whose gaze faces the camera from the front; Storage means for storing an eye image in front of the gaze obtained by the eye image extracting means; Image acquisition means for acquiring an image of the user during video communication; And Image synthesizing means for inserting an eye image of the eye gaze front stored in the storage means to the image acquired by the image acquiring means. Gaze matching image acquisition device for video communication comprising a. The method according to any one of claims 1 to 3, Image reproducing means for providing to the user the image of the user in line with the image transmitted from the other party Apparatus for obtaining gaze matching for video communication further comprising. In the gaze matching image acquisition method applied to a gaze matching image acquisition apparatus for video communication, A first step of acquiring a predetermined number of second images having a position movement of a second predetermined size with respect to two images captured by a camera, with a first image having a first predetermined size and a predetermined position as a center; The first image and each of the predetermined number of second images are combined to obtain a predetermined number of temporary gaze matching images, and to determine whether the temporary gaze matching image having the lowest error is an image obtained from the center of the second image. Determining a second step; A third step of determining the temporary gaze coincidence image as a gaze coincidence image when the temporary gaze coincidence image obtained at the center of the second image has the lowest error as a result of the determination of the second step; And As a result of the determination in the second step, if the temporary gaze coincidence image does not have a minimum error, an image having the lowest error among a predetermined number of temporary gaze coincidence images according to whether there is an image reaching a boundary among a predetermined number of second images. Is determined as a gaze coincidence image or is repeatedly performed from a process of acquiring a predetermined number of second images having a position shift of the second predetermined size of the first step based on the second image when the minimum error is obtained. 4 steps Gaze matching image acquisition method comprising a. The method of claim 5, wherein The fourth step, A fifth step of checking whether there is an image reaching the boundary of the entire second image among a predetermined number of second images if the temporary gaze coincidence image does not have a minimum error; And as a result of the checking of the fifth step, when there is an image reaching the boundary of the entire second image among the predetermined number of second images, the image which determines the image having the lowest error among the predetermined number of temporary gaze matching images as the gaze matching image. 6 steps; And As a result of the checking of the fifth step, if there is no image reaching the boundary of the entire second image among the predetermined number of second images, the second predetermined image of the first step is centered on the second image having the lowest error. A seventh step of repeatedly performing a process of acquiring a predetermined number of second images having a position shift of a size; Gaze matching image acquisition method comprising a. In the gaze matching image acquisition method applied to a gaze matching image acquisition apparatus for video communication, A first step of obtaining and storing an eye image to be used as a gaze matching image from a user; A second step of finding an insertion position through pattern matching in an image obtained from the user during video communication to insert a stored eye image; And A third step of acquiring a gaze-matched image by inserting a stored eye image for a matched gaze at a found position Gaze matching image acquisition method comprising a. The method of claim 7, wherein A fourth step of correcting the stored eye image to match the brightness of the user image during video communication Gaze matching image acquisition method further comprising. The method according to claim 7 or 8, A fifth step of eliminating boundary pass by performing low pass filtering on the boundary of the image inserted into the user image during the video communication; Gaze matching image acquisition method further comprising. In the gaze matching image acquisition device having a processor, A first function of acquiring a predetermined number of second images having a position movement of a second predetermined size about a first image having a first predetermined size and a predetermined position with respect to two images captured by a camera; The first image and each of the predetermined number of second images are combined to obtain a predetermined number of temporary gaze matching images, and to determine whether the temporary gaze matching image having the lowest error is an image obtained from the center of the second image. A second function of judging; A third function of determining the temporary gaze coincidence image as a gaze coincidence image when the temporary gaze coincidence image obtained at the center of the second image has the lowest error as a result of the determination of the second function; And As a result of the determination of the second function, if the temporary gaze coincidence image does not have a minimum error, an image having the lowest error among a predetermined number of temporary gaze coincidence images according to whether there is an image reaching a boundary among a predetermined number of second images. Is repeated as a gaze-matched image or a process of repeatedly acquiring a predetermined number of second images having a position shift of a second predetermined size of the first function based on the second image when the minimum error is obtained. 4 functions A computer-readable recording medium having recorded thereon a program for realizing this. In the gaze matching image acquisition device having a processor, A first function of acquiring and storing an eye image to be used as a gaze matching image from a user; A second function of finding an insertion position through pattern matching in an image obtained from the user during video communication to insert a stored eye image; And A third function of acquiring a gaze matching image by inserting an eye image for storing gaze matching into a found position A computer-readable recording medium having recorded thereon a program for realizing this.

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