JP2007004716A - Image processing method and image processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology to view a desired place from a stationary viewpoint in a virtual space. <P>SOLUTION: Everytime the position and posture of the viewpoint of an observer are acquired, data of the acquired position and posture is overridden in a memory and stored (S905). When a first indication is detected, processing is controlled not to perform storage processing in the memory (S904). The image of the virtual space to be viewed from the viewpoint having the position and posture stored in the memory is generated (S906) and the generated image is outputted (S908). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique for generating a real space image, particularly a virtual space image to be superimposed on the real space.

  In recent years, mixed reality technology (MR (Mixed Reality) technology) has been gained. The mixed reality technology is a technology for compositing and displaying live-action and CG. For example, a CG car appears in front of the eyes, or there is an electronic rice cooker that is being designed with 3D CAD (Computer Aided Design; hereinafter referred to as 3D-CAD).

  In the industrial product manufacturing industry, 3D-CAD has recently been used for mechanical design and design design. Therefore, the 3D model is displayed on the computer screen before or after creating the actual machine mockup or the mechanical examination using the actual machine mockup (model) of the product as was done conventionally. It has become possible to do this.

  The 3D model for examination reproduced in the virtual world inside the computer is to be examined by simultaneously observing the digital mockup (DM or DMU) and the screen on which the digital mockup is projected by a large number of people. Called Digital Mockup Review (DMR).

  In DMR, the digital mockup of the target product is observed from various angles. While observing the digital mockup from the position where the mechanical mechanism / design evaluation is most effective, the position / posture of the camera inside the computer is moved while moving or stopping specific parts.

  However, in the conventional DMR, it is difficult to move the position / posture of the camera in the virtual world inside the computer that captures the digital mockup to a desired location, and only a complete virtual world image inside the computer can be observed. There was a problem that it was difficult to grasp the size of the digital mockup.

Therefore, using MR technology, the position and orientation of the camera in the virtual world inside the computer need only be moved by the actual camera, and a virtual digital mockup is superimposed on the real world and displayed. Therefore, there is an advantage that the size of the digital mockup can be easily grasped. Therefore, MR technology is considered promising in the field of DMR.
JP 2005-107970 A

  However, the position / posture of the camera in the mixed reality world also moves with the movement of the position / posture of the camera operated by the subject. Therefore, it becomes difficult to observe the mixed reality world to be observed from a stationary viewpoint, and it is difficult to keep an eye on a portion to be noticed in a DMR that observes a detailed mechanical mechanism and design by a large number of people. Furthermore, it is difficult or impossible to indicate a specific part in the mixed reality world observed from a certain viewpoint.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique that enables a desired location in a virtual space to be viewed from a stationary viewpoint.

  In order to achieve the object of the present invention, for example, an image processing method of the present invention comprises the following arrangement.

That is, an acquisition step of acquiring the position and orientation of the observer's viewpoint,
Each time the position and orientation are acquired in the acquisition step, a storage control step of overwriting and storing the acquired position and orientation data in a memory; and
A first control step for controlling processing by the storage control step so as not to perform storage processing for the memory when a first instruction is detected;
Generating a virtual space image viewed from a viewpoint having a position and orientation stored in the memory;
An output step of outputting the image generated in the generation step.

  In order to achieve the object of the present invention, for example, an image processing apparatus of the present invention comprises the following arrangement.

That is, acquisition means for acquiring the position and orientation of the observer's viewpoint,
Each time the acquisition unit acquires a position and orientation, a storage control unit that overwrites and stores the acquired position and orientation data in a memory; and
A first control unit that controls the storage control unit so as not to perform a storage process on the memory when a first instruction is detected;
Generating means for generating an image of a virtual space seen from a viewpoint having a position and orientation stored in the memory;
Output means for outputting the image generated by the generating means.

  With the configuration of the present invention, a desired location in the virtual space can be viewed from a stationary viewpoint.

  Hereinafter, the present invention will be described in detail according to preferred embodiments with reference to the accompanying drawings.

[First Embodiment]
<Regarding the conventional system>
First, a conventional system for performing DMR using MR technology will be described.

  FIG. 1 is a diagram illustrating a configuration example of a conventional system for performing DMR using MR technology.

  A head-mounted display device (a so-called HMD (Head Mount Display)) 110 is mounted on the head of the observer 100.

  FIG. 2 is a diagram illustrating the configuration of the HMD 110.

  The HMD 110 includes a small display device 112 such as an LCD, a small video camera 111, and prisms 114 and 115. The real space that would otherwise be viewed by the observer 100 is captured as an image by the small video camera 111, and the observer 100 sees the image displayed on the small display device 112.

  The real space image captured by the small video camera 111 is output to the computer 140 at the subsequent stage. Hereinafter, the small video camera 111 may be referred to as “the viewpoint of the observer 100”.

  The position / orientation sensor 113 is integrally attached to the HMD 110 and measures its own position and orientation. For such a position / orientation sensor 113, FASTRAK (registered trademark) manufactured by Polhemus, Inc., USA can be used. When the position / orientation sensor 113 is FASTRAK, it is used in combination with the transmitter 130 and the main body 131.

  For example, when the position / orientation sensor 113 is a magnetic sensor, a magnetic field is generated from the transmitter 130. Therefore, the position / orientation sensor 113 detects magnetism corresponding to its own position and orientation and sends a signal indicating the detection result to the main body 131. Output. The main body 131 generates data indicating the position and orientation of the position and orientation sensor 113 based on the received signal. The generated data is output to the computer 140 at the subsequent stage. The position and orientation data acquired in this way is a coordinate system (sensor coordinate system) in which the position of the transmitter 130 in the real space is an origin, and three axes orthogonal to each other at the origin are x, y, and z axes, respectively. ) Is data indicating the position and orientation. In addition, since the technique for acquiring the position and orientation of the position and orientation sensor itself using the position and orientation sensor is well known, further description thereof is omitted.

  In the figure, reference numeral 160 denotes a region where the mixed reality space can be presented to the viewer 100. The viewer 100 is a composite of the real space and the virtual space synthesized within the region shown in FIG. You can experience real space. Accordingly, within the area 160, a virtual object can be arranged with an arbitrary position and orientation and size. In the figure, a real object 170 and a virtual object 180 exist in the area 160 of the mixed reality space.

  The computer 140 uses the position and orientation data output from the main body 131 to generate an image of the virtual space that can be seen from the observer's viewpoint. The generated virtual space image is superimposed on the real space image output from the HMD 110 (strictly, the small video camera 111), and the small display device 112 provided in the HMD 110 and a display for a large number of people described later. Output to the device 120. The virtual object 180 in the area 160 is generated by the computer 140.

  The multi-person display device 120 is provided to the computer 140 in order to provide an image (an image of the mixed reality space displayed on the small display device 112) observed by the observer 100 to an observer other than the observer 100. The image output from is displayed. Thereby, the participant who participates in DMR besides the observer 100 can examine a mechanical mechanism and a design, observing the image displayed on the display apparatus 120 for many people.

  FIG. 3 is a diagram showing a functional configuration of the system centered on the computer 140. As shown in the figure, the computer 140 includes a video image acquisition unit 301, a camera position / posture output unit 302, a CG / video display unit 303, a CG / video composition unit 304, and a CG generation unit 305. The camera position / posture output unit 302 includes a camera position / posture acquisition unit 302a.

  The camera position / orientation acquisition unit 302a uses the position / orientation data measured by the position / orientation sensor 113 to update data indicating the position / orientation of the viewpoint of the observer 100 (camera position / orientation data 302b for CG drawing). . Here, as is well known, a position / orientation relationship between the position / orientation sensor 113 and the viewpoint of the observer 100 is obtained in advance as bias data, and this bias data and position / orientation data measured by the position / orientation sensor 113 (i.e., The position and orientation data of the viewpoint can be obtained by adding the position and orientation sensor 113 itself to the position and orientation data in the sensor coordinate system. Therefore, the camera position / orientation data 302b for CG drawing is the position / orientation data of this viewpoint, and the camera position / orientation acquisition unit 302a is as described above each time it acquires the position / orientation data measured by the position / orientation sensor 113. Thus, the position / orientation data of the viewpoint is obtained, and the processing for updating the CG drawing camera position / orientation data 302b with the obtained data is performed.

  The CG data 306 is a data group necessary for generating an image of the virtual space. For example, when each virtual object constituting the virtual space is composed of polygons, normal vector data of the polygon, polygon When texture mapping is applied to the coordinate data of each vertex, polygon color data, and this virtual object, the texture data is also included in this CG data 306. The CG data 306 may be the above digital mockup data, may be created by 3D-CAD or the like, or may be converted for this system.

  The CG generation unit 305 generates an image of a virtual space that can be seen from the viewpoint of the observer 100 using the CG drawing camera position / orientation data 302b and the CG data 306. In addition, since the process which produces | generates the image of the virtual space seen from the viewpoint which has a predetermined position and orientation is a well-known thing, the further description is abbreviate | omitted.

  The video image acquisition unit 301 acquires the real space image output from the small video camera 111 provided in the HMD 110 and outputs the acquired image to the CG / video synthesis unit 304 at the subsequent stage. The CG / video composition unit 304 superimposes the virtual space image generated by the CG generation unit 305 on the real space image received from the video image acquisition unit 301 to generate a mixed reality space image. Output to the video display unit 303.

  The CG / video display unit 303 outputs the received mixed reality space image to the small display device 112 provided in the HMD 110 or the display device 120 for a large number of people.

  With the above configuration, an image of the mixed reality space that can be seen according to the position and orientation of the viewpoint of the viewer 100 can be generated and output to the small display device 112 provided in the HMD 110 or the display device 120 for many people. it can.

<System according to this embodiment>
Next, a system according to the present embodiment will be described.

  FIG. 4 is a diagram illustrating a configuration example of a system according to the present embodiment. The same parts as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted. The system according to the present embodiment is different from the conventional system in that a push button switch 401 is connected to the computer 140 in addition to the configuration shown in FIG.

  The push button switch 401 is held by the observer 100 in his / her hand. For example, the observer 100 is observing the mixed reality space, and the viewpoint of the virtual object to be examined is most easily observed. This is pressed when the virtual object to be examined is displayed on the small display device 112 in a state that is most easily observed. When the push button switch 401 is depressed, a signal indicating that the push button switch 401 has been depressed is output to the computer 140.

  FIG. 5 is a block diagram showing a functional configuration of the system according to the present embodiment. The same parts as those in FIG. 3 are denoted by the same reference numerals, and the description thereof is omitted. 3 is different from the configuration shown in FIG. 3 in that the function configuration of the computer 140 is further added with an event detection unit 501 in addition to the configuration shown in FIG. 3, and the camera position / posture acquisition unit 302a is a camera position / posture acquisition unit. 302c.

  When the event detection unit 501 receives a signal indicating that the push button switch 401 has been pressed from the push button switch 401, the event detection unit 501 detects this and notifies the camera position and orientation acquisition unit 302c. Regarding the basic operation of the camera position / orientation acquisition unit 302c, in addition to the operation of the camera position / orientation acquisition unit 302a, upon receiving a notification from the event detection unit 501, updating of the CG drawing camera position / orientation data 302b is stopped. That is, when the push button switch 401 is pressed, the update of the CG drawing camera position / posture data 302b is stopped according to the timing, so that it can be seen from the viewpoint of the same position / posture after the push button switch 401 is pressed. A virtual space image is generated. That is, an image of a virtual space that can be seen from a stationary viewpoint can be obtained.

  When the push button switch 401 is pressed again, the event detection unit 501 similarly notifies the camera position / posture acquisition unit 302c, and the camera position / posture acquisition unit 302c stores the CG drawing camera position / posture data 302b. Resume update. That is, each time the push button switch 401 is pressed, it is possible to switch whether or not to update the CG drawing camera position and orientation data 302b.

  FIG. 6 is a diagram illustrating a state chart showing how to switch whether to update the CG drawing camera position / orientation data 302b each time the push button switch 401 is pressed.

  When the computer 140 is activated, the camera position / orientation acquisition unit 302c operates to update the CG drawing camera position / orientation data 302b. That is, as described above, when the position / orientation data measured by the position / orientation sensor 113 is received via the main body 131, the viewpoint position / orientation data is obtained based on the received data, and the CG is obtained using the obtained data. The drawing camera position / orientation data 302b is updated.

  Here, when the observer 100 presses the push button switch 401, the event detection unit 501 notifies the camera position and orientation acquisition unit 302c that the button has been pressed, so the camera position and orientation acquisition unit 302c performs CG drawing camera position and orientation data. Operate to stop updating 302b. That is, as described above, even if the position / orientation data measured by the position / orientation sensor 113 is received via the main body 131, no operation is performed on the CG drawing camera position / orientation data 302b. Therefore, after receiving the notification from the event detection unit 501, the CG drawing camera position / orientation data 302b does not change at all.

  Therefore, no matter how the position / orientation of the viewpoint of the observer 100 changes in this state, the CG drawing camera position / orientation data 302b does not change at all, and is displayed on the small display device 112 and the multi-person display device 120. Each virtual object in the mixed reality space image is viewed from a stationary viewpoint. Thereby, for example, when the observer 100 moves his / her viewpoint to a position and orientation in which the virtual object to be examined is most easily observed and presses the push button switch 401 there, the multi-person display device 120 has a push button. Since the virtual space image seen from the viewpoint of the observer 100 at the time when the switch 401 is pressed is displayed in a state of being superimposed on the real space image, the multi-person display device 120 displays the virtual object to be examined. It becomes easy to point on the display screen, and it becomes easy to examine with a large number of people.

  When the push button switch 401 is pressed again, the event detection unit 501 similarly notifies the camera position / orientation acquisition unit 302c, and the camera position / orientation acquisition unit 302c again performs CG drawing camera position / orientation data. Restart the update of 302b.

  FIG. 8 is a diagram illustrating a hardware configuration of the computer 140. As such a computer 140, a general PC (personal computer), WS (workstation), or the like can be applied.

  Reference numeral 801 denotes a CPU that controls the entire computer 140 using programs and data stored in the RAM 802 and the ROM 803, and executes each process described below performed by the computer 140.

  Reference numeral 802 denotes a RAM, an area for temporarily storing programs and data loaded from the external storage device 806, an area for temporarily storing various data received via the I / F 807, and various types of CPUs 801. Various areas such as a work area used for executing the process can be provided as appropriate.

  A ROM 803 stores setting data and a boot program of the computer 140.

  An operation unit 804 includes a keyboard and a mouse, and various instructions can be input to the CPU 801 by an operator of the computer 140. The operation unit 804 may be used instead of the push button switch 401.

  A display unit 805 includes a CRT, a liquid crystal screen, and the like, and can display a processing result by the CPU 801 using an image, text, or the like. You may make it use this display part 805 as the said display apparatus 120 for many people.

  Reference numeral 806 denotes an external storage device, which is a large-capacity information storage device typified by a hard disk drive device, in which an OS (Operating System) and programs and data for causing the CPU 801 to execute various processes performed by the computer 140 ( (Including the bias data, CG data 306, etc.) are stored, and are loaded into the RAM 802 as required by the CPU 801.

  Reference numeral 807 denotes an I / F, to which the HMD 110, the main body 131, the multi-person display device 120, the push button switch 401, and the like can be connected. Data communication with these devices is performed via the I / F 807. Is called. Note that an I / F 807 may be provided for each apparatus.

  A bus 808 connects the above-described units.

  Next, processing for generating an image of the mixed reality space for one frame by the computer 140 will be described with reference to FIG. 9 showing a flowchart of the processing. Note that programs and data for causing the CPU 801 to execute the processing according to the flowchart of FIG. 8 are stored in the external storage device 806, and these are loaded into the RAM 802 as appropriate under the control of the CPU 801, and the CPU 801 uses this. By executing the process, the computer 140 executes each process described below.

  Since real space images captured by the small video camera 111 provided in the HMD 110 are sequentially input to the computer 140 via the I / F 807, the CPU 801 stores the sequentially input images in a video buffer in the RAM 802. Store (step S901).

  On the other hand, since data indicating the position and orientation of the position and orientation sensor 113 is input from the main body 131 into the computer 140 via the I / F 807, the CPU 801 stores the input position and orientation data in a predetermined area in the RAM 802, Alternatively, it is stored in the external storage device 806 (step S902). Note that the processing in step S901 and the processing in step S902 are not limited to being performed in this order, and may be performed in parallel by well-known multithread processing.

  The CPU 801 obtains the position and orientation of the viewpoint by adding the position and orientation data acquired in step S902 and the bias data loaded from the external storage device 806 to the RAM 802 (step S903). As described above, since the processing for obtaining the position and orientation of the viewpoint from the measured position and orientation is well known, a description thereof will be omitted.

  Next, the CPU 801 checks whether a signal indicating that the observer 100 has pressed the push button switch 401 is input from the push button switch 401 to the computer 140 via the I / F 807 (step S904). If the effect is not detected, the process proceeds to step S905, and the viewpoint position and orientation data obtained in step S903 is stored in an area (hereinafter referred to as position and orientation data) provided in the RAM 802 or the external storage device 806. By overwriting and storing in the storage area), the “viewpoint position and orientation data” stored in the position and orientation data storage area is updated (step S905).

  Next, the CPU 801 uses the CG data 306 loaded from the external storage device 806 to the RAM 802 and the “viewpoint position / orientation data” stored in the position / orientation data storage area, so that the virtual image can be viewed from the viewpoint. A process of generating an image of the space is performed (step S906). If the computer 140 has hardware dedicated to image processing, the processing in this step may be performed by the hardware dedicated to image processing.

  On the other hand, if it is detected that the button has been pressed, the process proceeds from step S904 to step S906. In other words, when it is detected that the push button switch 401 is pressed, the processing in step S905 is not performed. Therefore, the viewpoint of the virtual space image generated in step S906 has been previously stored in the position and orientation data storage area. This is in accordance with the “viewpoint position and orientation data”.

  Next, the CPU 801 generates a mixed reality space image by superimposing the virtual space image generated in step S906 on the real space image stored in the video buffer in step S901 (step S907). This is output to the small display device 112 provided in the HMD 110 and the multi-person display device 120 via the I / F 807 (step S908).

  In the process according to the flowchart of FIG. 9, a mode (first mode) for storing viewpoint position / orientation data in the position / orientation data storage area is set in advance in the computer 140, and the push button switch It is assumed that when 401 is pressed, the position / orientation data of the viewpoint is switched to a mode (second mode) in which the data is not stored in the position / orientation data storage area.

  Further, regarding the processing when the push button switch 401 is pressed when the second mode is set, the branch destination in step S904 may be reversed in the flowchart of FIG. In other words, if it is detected that the push button switch 401 is pressed, the process proceeds to step S905. If not detected, the process proceeds to step S906.

  That is, every time the push button switch 401 is pressed, the first mode and the second mode are alternately switched.

[Second Embodiment]
In the first embodiment, every time the push button switch 401 is pressed, the first mode and the second mode are alternately switched. However, a mode other than the push button switch 401 is used to switch the mode. May be. For example, the mode may be switched every time a predetermined sound is input, or the mode may be switched every time the observer 100 recognizes the predetermined gesture.

  In the first embodiment, as shown in FIG. 6, when storing the position and orientation data of the viewpoint in the position and orientation data storage area is prohibited, if the push button switch 401 is pressed, The operation of storing the position and orientation data in the position and orientation data storage area is resumed. However, as shown in FIG. 7, when the position / orientation data of the viewpoint is prohibited from being stored in the position / orientation data storage area, when the push button switch 401 is pressed, the viewpoint position / orientation data is directly displayed. Is not resumed, but the processing described below is performed.

  That is, when storing the position / orientation data of the viewpoint in the position / orientation data storage area, when the push button switch 401 is pressed, the position / orientation of the viewpoint obtained near the timing at which the pressing is detected is determined. The difference value between the data and the viewpoint position / orientation data stored in the position / orientation data storage area (difference between positions, difference between attitudes) is obtained, and the difference value between positions or the difference between attitudes is predetermined. If it is greater than or equal to the value, the position / orientation data stored in the position / orientation data storage area is corrected so that the difference value is reduced by a predetermined amount (for example, 1/20 of the difference value) for each frame. To do. If one or both of the difference values are equal to or less than the predetermined value, the operation of storing the viewpoint position / orientation data in the position / orientation data storage area is resumed as in the first embodiment. .

  In the first embodiment, the observer 100 wears the HMD 110 on his / her head and observes an image of the mixed reality space displayed on the small display device 112 provided in the HMD 110. In order for the observer 100 to observe the image displayed on the multi-person display device 120 and perform the same examination as the other observers, the following modifications may be considered.

  That is, at least the position / orientation sensor 113 and the small video camera 111 are mounted on the head of the observer 100, and the image of the real space seen from the viewpoint of the observer 100 and the position / orientation data of the position / orientation sensor 113 are stored in the computer 140. Output to. As described above, the computer 140 generates an image of the mixed reality space that can be seen from the viewpoint of the observer 100, and outputs this to the multi-person display device 120.

  Thereby, the observer 100 can observe the image of the mixed reality space that can be seen from his / her viewpoint through the display device 120 for many people, not through the HMD 110, and can perform the same examination as other observers. it can.

[Other Embodiments]
An object of the present invention is to supply a recording medium (or storage medium) that records software program codes for realizing the functions of the above-described embodiments to a system or apparatus, and the computer of the system or apparatus (or CPU or MPU). Needless to say, this can also be achieved by reading and executing the program code stored in the recording medium. In this case, the program code itself read from the recording medium realizes the functions of the above-described embodiment, and the recording medium on which the program code is recorded constitutes the present invention.

  Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instruction of the program code. It goes without saying that a case where the function of the above-described embodiment is realized by performing part or all of the actual processing and the processing is included.

  Furthermore, after the program code read from the recording medium is written into a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the function is based on the instruction of the program code. It goes without saying that the CPU or the like provided in the expansion card or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing.

  When the present invention is applied to the recording medium, program code corresponding to the flowchart described above is stored in the recording medium.

It is a figure which shows the structural example of the conventional system for performing DMR using MR technique. It is a figure which shows the structure of HMD110. 2 is a diagram illustrating a functional configuration of a system centered on a computer 140. FIG. It is a figure which shows the structural example of the system which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the function structure of the system which concerns on the 1st Embodiment of this invention. It is a figure which shows a state chart which shows a mode that it switches whether it updates the camera position and orientation data 302b for CG drawing, whenever the pushbutton switch 401 is pressed. It is a figure which shows a state chart which shows a mode that it switches whether it updates the camera position and orientation data 302b for CG drawing, whenever the pushbutton switch 401 is pressed. 2 is a diagram illustrating a hardware configuration of a computer 140. FIG. It is a flowchart of the process for producing | generating the image of the mixed reality space for 1 frame.

Claims (6)

An acquisition step of acquiring the position and orientation of the observer's viewpoint;
Each time the position and orientation are acquired in the acquisition step, a storage control step of overwriting and storing the acquired position and orientation data in a memory; and
A first control step for controlling processing by the storage control step so as not to perform storage processing for the memory when a first instruction is detected;
Generating a virtual space image viewed from a viewpoint having a position and orientation stored in the memory;
An image processing method comprising: an output step of outputting the image generated in the generation step. In the first control step, when the storage control process is controlled so as not to perform the storage process for the memory,
And a second control step of controlling processing by the storage control step so as to resume storage processing for the memory when a second instruction different from the first instruction is detected. The image processing method according to claim 1. Furthermore,
Comprising an image acquisition step of acquiring an image of a real space visible from the viewpoint;
3. The image processing according to claim 1, wherein in the output step, the image of the virtual space generated in the generation step is superimposed and output on the image of the real space acquired in the image acquisition step. Method. Acquisition means for acquiring the position and orientation of the observer's viewpoint;
Each time the acquisition unit acquires a position and orientation, a storage control unit that overwrites and stores the acquired position and orientation data in a memory; and
A first control unit that controls the storage control unit so as not to perform a storage process on the memory when a first instruction is detected;
Generating means for generating an image of a virtual space seen from a viewpoint having a position and orientation stored in the memory;
An image processing apparatus comprising: an output unit that outputs an image generated by the generation unit.   A program for causing a computer to execute the image processing method according to any one of claims 1 to 3.   A computer-readable storage medium storing the program according to claim 5.

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