JP2007058709A - Image processor, image processing method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor, capable of obtaining a display of an object free from sense of discomfort by mutually associating attitude change with position change of the object. <P>SOLUTION: This image processor comprises a center-of-gravity position calculation part 30 calculating a center-of-gravity position of the object based on motion data at predetermined time intervals; a center-of-gravity movement quantity calculation part 32 calculating a movement quantity of the center-of-gravity position of the object per predetermined time; and a position/attitude determination part 34 determining the position of the object based on the center-of-gravity position of the object when the movement quantity per predetermined time of the direction separating from a field object in the center-of-gravity position exceeds a given threshold, and determining the position of the object based on the position of the contact part with the field object of the object when the movement quantity per predetermined time of the direction separating from the field object in the center-of-gravity position is less than the given threshold. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image processing apparatus, an image processing method, and a program, and more particularly to a technique for realizing the movement of an object arranged in a virtual three-dimensional space.

  In the field of 3D CG in which a virtual 3D space is constructed in a computer, and a humanoid object is placed in this space, and the state viewed from an arbitrary viewpoint in the space is visualized by a display, The movements of the objects are stored in advance as motion data, and the movements of the objects are realized by reproducing the motion data. The motion data is obtained, for example, by a method called motion capture that generates motion data from actual human movements. Such a technique is disclosed in Patent Documents 1 and 2, for example.

In particular, when the object is moved freely in the virtual three-dimensional space using the motion data, the posture change is reproduced by the motion data, and the position change in the virtual three-dimensional space is separately performed, for example, according to a user operation. Often decided.
JP 2003-85592 A JP-A-11-306388

  However, in the above prior art, when the posture change of the object is reproduced by the motion data and the position change of the object in the virtual three-dimensional space is calculated separately, the posture change of the object and the position change of the object are linked. Therefore, an unnatural display may be caused. For example, the user feels uncomfortable when the position of the object remains fixed on the ground despite the fact that the center of gravity of the object has changed drastically and the posture is likely to jump off the ground.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an image processing apparatus, an image processing method, and an image processing apparatus capable of obtaining a display of an object without a sense of incongruity by linking an object posture change and a position change To provide a program.

  In order to solve the above problems, an image processing apparatus according to the present invention changes the posture of an object arranged on a field object in a virtual three-dimensional space based on motion data indicating transition of the posture of the object. And an image processing device for displaying an image showing the virtual three-dimensional space viewed from a given viewpoint arranged in the virtual three-dimensional space, wherein the object is displayed at predetermined time intervals based on the motion data. Centroid position calculating means for calculating the centroid position of the object, centroid movement amount calculating means for calculating the amount of movement of the centroid position of the object per predetermined time, and for the predetermined time in the direction away from the field object of the centroid position When the amount of movement exceeds a predetermined threshold, the position of the object is set to the center of gravity position of the object. And determining the position of the object based on the position of the contact portion of the object with respect to the field object when the amount of movement of the center of gravity in the direction away from the field object per predetermined time is less than a predetermined threshold. And position determining means for determining the position.

  The image processing method according to the present invention changes the posture of an object arranged on a field object in a virtual three-dimensional space based on motion data indicating a transition of the posture of the object, An image processing method for displaying an image showing a virtual three-dimensional space viewed from a given viewpoint arranged in a space, wherein the center of gravity position of the object is calculated every predetermined time based on the motion data A center-of-gravity position calculating step; a center-of-gravity movement amount calculating step of calculating a movement amount of the center-of-gravity position of the object per predetermined time; and a movement amount per predetermined time in the direction away from the field object of the center-of-gravity position is a predetermined threshold value The position of the object is determined based on the position of the center of gravity of the object. A position for determining the position of the object based on the position of the contact portion of the object with respect to the field object when the amount of movement of the center of gravity in the direction away from the field object per predetermined time is less than a predetermined threshold value And a determining step.

  Further, the program according to the present invention changes the posture of an object arranged on a field object in the virtual three-dimensional space based on motion data indicating a transition of the posture of the object, and in the virtual three-dimensional space. Means for displaying an image showing the virtual three-dimensional space viewed from a given viewpoint, a center-of-gravity position calculating means for calculating the center-of-gravity position of the object at predetermined intervals based on the motion data, and the predetermined Centroid movement amount calculating means for calculating a movement amount of the centroid position of the object per time, and when the movement amount per predetermined time in the direction away from the field object of the centroid position exceeds a predetermined threshold, A position is determined based on the position of the center of gravity of the object, and the position of the center of gravity is A computer functioning as position determining means for determining the position of the object based on the position of the contact portion of the object with respect to the field object when the amount of movement per predetermined time in the direction away from the object is less than a predetermined threshold It is a program to make it. This program may be stored in various computer-readable information storage media such as a CD-ROM and a DVD-ROM. The computer is, for example, a home game machine, an arcade game machine, a portable game machine, a mobile phone, a portable information terminal, a personal computer, a server computer, or the like.

  In the present invention, the center of gravity position of the object is calculated every predetermined time based on the motion data, and the movement amount of the center of gravity position of the object per predetermined time is calculated. When the amount of movement away from the field object exceeds a predetermined threshold, the position of the object is determined based on the position of the center of gravity. For example, the position of the center of gravity may be parabolically moved in a virtual three-dimensional space, and the relative position of each part of the object may be determined with reference to that. If the movement amount is less than the predetermined threshold value, it is determined based on the position of the contact portion of the object with respect to the field object. For example, the position of the contact portion may be determined such that the contact portion contacts the field object, and the relative position of each part of the object may be determined based on the contact portion. The predetermined threshold may be a drop distance per predetermined time when the object freely falls in a virtual three-dimensional space. According to the present invention, the amount of movement of the center of gravity position of the object is calculated based on the motion data indicating the change in the posture of the object, and the method for determining the position of the object is appropriately changed according to the amount of movement. It is possible to link the change and the position change to obtain a display of an object with no sense of incongruity.

  The position determination means performs a parabolic motion of the center of gravity position of the object in the virtual three-dimensional space when the amount of movement of the center of gravity position in a direction away from the field object per predetermined time exceeds a predetermined threshold. At the same time, the position of the object may be determined based on the position of the center of gravity where the parabola moves.

  In addition, the position determination unit may be configured to detect the position of the center of gravity at a predetermined time in a direction away from the field object when a moving amount per predetermined time in a direction away from the field object is less than the predetermined threshold. The contact portion may be separated from the field object according to whether the amount of movement exceeds a predetermined threshold.

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

  FIG. 1 is a schematic diagram showing a virtual three-dimensional space constructed on a memory in an image processing apparatus according to an embodiment of the present invention. As shown in the figure, in the virtual three-dimensional space 10, a flat field object 12 is arranged on the XZ plane (in the global coordinate system), and a human character object 14 is arranged on the field object 12. The character object 14 changes its posture in accordance with the motion data, and performs actions such as jumping, squatting, walking on the field object 12. The motion data does not include the position information of the character object 14 but includes only the information on the posture change. That is, the motion data includes data indicating the posture of the character object 14 every predetermined time in time series. For this reason, the position change (movement of the representative position) of the character object 14 is calculated separately.

The character object 14 has the bone structure shown in FIG. 2, and the bone U ₁ extends upward from the representative position (root position) R, and the bone U ₂ extends further upward from the tip thereof. Further, the bone groups U _{R1 to} U _R4 and the bone groups U _{L1 to} U _L4 connected in order are connected to the connection points of the bone U ₁ and the bone U ₂ . Also, bone L ₁ is stretched downward from the representative position R, further from a position offset to the left and right obliquely upward from the tip position, downwards respectively, groups bones coupled sequentially L _{R1 ~L R3,} bone group L _L1 ~ L _L3 is stretched. These bones have a tree structure as shown in FIG. 3. When the representative position R is determined, the position of each bone is determined accordingly. Further, when the positions and postures of the bone L _L3 and the bone L _R3 are determined, the representative position R and the positions and postures of other bones are determined accordingly (inverse kinematics).

  Further, in the present embodiment, calculation of the center of gravity position of the character object 14 is performed. As shown in FIG. 4, the character object 14 is composed of parts W1 to W15. The center of gravity Pn of each part (global coordinates in the virtual three-dimensional space 10) and the load ratio αn (the weight of each part relative to the total weight). (Occupying ratio) is always managed by the table shown in FIG. 5 (n = 1 to 15). Here, the center-of-gravity position P of the entire character object 14 is calculated by the following equation (1).

  Αn satisfies the following expression (2), and is determined statistically or empirically with reference to the actual human weight distribution.

  Here, the hardware configuration of the image processing apparatus according to the present embodiment will be described. FIG. 6 shows a hardware configuration of the image processing apparatus. As shown in FIG. 6, the image processing apparatus 20 is a conventionally known computer system including a storage unit 26, a calculation unit 22, and a display unit 24. . The storage unit 26 is configured by a semiconductor storage device such as a RAM or a magnetic storage device such as a hard disk storage device. In particular, the storage unit 26 stores the shapes and patterns of various objects arranged in the virtual three-dimensional space 10 such as the character object 14. Object data storage unit 26a that stores data (polygon data, texture data, etc.) to be shown, and motion that stores motion data that indicates the movement (posture change) of various objects arranged in the virtual three-dimensional space 10 such as the character object 14 A data storage unit 26b. The calculation unit 22 is configured by a known computer including a CPU, a RAM, and the like, calculates the positions and postures of various objects arranged in the virtual three-dimensional space 10, and sets these objects in the virtual three-dimensional space 10. The state seen from the viewpoint is made into an image and supplied to the display unit 24. The display unit 24 receives and outputs this image, and is composed of, for example, a CRT or LCD. The display unit 24 may be a home television receiver, for example, and the storage unit 26 and the calculation unit 22 may be a home game machine or a personal computer, for example.

  The image processing apparatus 20 realizes various functions by executing the image processing program according to the present embodiment. That is, as shown in FIG. 7, the image processing apparatus 20 functionally includes a gravity center position calculation unit 30, a gravity center movement amount calculation unit 32, a position / posture determination unit 34, an image generation unit 36, and an object data storage unit 26a. , A motion data storage unit 26b, and a display unit 24 are included. These functions are realized by executing a predetermined program in the image processing apparatus 20 which is a computer system.

  First, the center-of-gravity position calculation unit 30 calculates the center-of-gravity position of the character object 14 every predetermined time according to the above equation (1). At this time, the position coordinate Pn of each part Wn of the character object 14 at each time is determined based on the motion data stored in the motion data storage unit 26b. Next, the center-of-gravity movement amount calculation unit 32 calculates the distance between the center-of-gravity positions of the character object 14 calculated by the center-of-gravity position calculation unit 30 every predetermined time. The distance calculated in this way is supplied to the position / posture determination unit 34 as a center-of-gravity movement amount per predetermined time (center-of-gravity position calculation interval).

The position / posture determination unit 34 determines whether the amount of movement of the character object 14 in the direction away from the field object 12 at the center of gravity (that is, the Y direction in the global coordinate system) exceeds a predetermined threshold value. If the predetermined threshold value is exceeded, the position of the character object 14 is determined based on the position of the center of gravity of the character object 14. If it is less than the predetermined threshold, the position of the foot portion of the character object 14 (the contact portion with the field object 12, such as bones L _R3 and L _L3 and parts W6 and W9) is used as a reference. The position of the character 14 is determined. Here, the predetermined threshold is a drop distance per predetermined time when the character object 14 freely falls.

  Specifically, the position / posture determination unit 34 determines the position of the center of gravity of the character object 14 as a virtual 3 when the amount of movement of the center of gravity of the character object 14 in a direction away from the field object 12 per predetermined time exceeds a predetermined threshold. While performing a parabolic motion in the dimension space 10, the position of the character object 14 is determined based on the center of gravity position where the parabolic motion is performed. Further, when the amount of movement of the character object 14 in the direction away from the field object 12 in the direction away from the field object 12 is less than the predetermined threshold, the amount of movement of the foot part in the direction away from the field object 12 in the direction of predetermined time exceeds the predetermined threshold. The foot portion is separated from the field object 12 depending on whether or not the distance is exceeded.

  The image generation unit 36 displays an image of the virtual three-dimensional space 10 in which the field object 12 and the character object 14 are arranged, that is, the virtual three-dimensional space 10 from a given viewpoint arranged in the virtual three-dimensional space 10. The appearance is generated and supplied to the display unit 24. The display unit 24 displays and outputs this image.

  FIG. 8 is a flowchart showing a process for calculating the position and orientation of the character object 14 in the image processing apparatus 20. As shown in the figure, in this process, the position / posture determination unit 34 first reads motion data from the motion data storage unit 26b (S101). This motion data does not include movement information in the global coordinate system as described above. In the initial state, the character object 14 is in a stable posture, that is, a posture in which both feet are extended with respect to the ground (field object 12). Have taken. Then, the position / posture determination unit 34 determines the position and posture of the character object 14 by using the read motion data so that both feet of the character object 14 are in contact with the field object 12 (S102). That is, both the foot portions are in contact with the field object 12 to determine the positions and postures of those portions, and then, based on the positions and postures of both foot portions, the position and the position of the other portions are determined by inverse kinematics. Determine posture. Next, the center-of-gravity position calculation unit 30 reads the motion data at the next time (frame) stored in the motion data storage unit 26b, and calculates the center-of-gravity position of the character object 14 based on the motion data (S103).

Next, it is determined whether one leg of the character object 14 is lifted (S104). FIG. 9 is a diagram for explaining this determination. In the figure, W _R is the load applied to the right foot of the character object 14, W _L is the load applied to the left foot of the character object 14. The P _R is a ground position of the right leg, P _L is a ground position of the left foot. Further, P 'is the position of the perpendicular foot drawn from the gravity center position P with respect to the line segment formed by connecting a P _R and P _L. At this time, P _R 'and the distance between the, P' P and P _L and the distance between the, the ratio of 1-omega: When omega, W _R and W _L are the following equations (3 ) And (4).

Alternatively, when the gravity center position P of the character object 14 is not directly above the line segment P _R P _L , as shown in FIG. 10, the direction from the gravity center position P to P ′ and the vertical direction (−Y direction). The following formulas (5) to (7) are established, where θ is the angle between and the load component of the character object 14 exerted on the line segment P _R P _L is W1. These equations coincide with the above equations (3) and (4) when θ = 0.

Here, the gravitational acceleration of the right foot (acceleration when the right foot falls) and the gravitational acceleration of the left foot (acceleration when the left foot falls) are expressed by the following equations (8) and (9), respectively.

  Then, using these values, it is determined whether or not the following expressions (10) and (11) are satisfied for the left and right feet. If satisfied, it is determined that each foot can float from the field object 12.

Here, the left side of Expression (10) is the movement distance per frame time of the right foot portion indicated by the motion data in the vertical direction (Y direction, that is, the direction in which the right foot portion is separated from the field object 12). Also, the right-hand side of Equation (10) is a falling distance when the right foot portion was dropped over one frame time by the acceleration g _R of formula (8). Similarly, the left side of Expression (11) is the movement distance per frame time of the left foot portion indicated by the motion data in the vertical direction (Y direction, that is, the direction in which the left foot portion is separated from the field object 12). Further, the right side of the equation (11) is a fall distance when the left foot part falls for one frame time due to the acceleration g _L of the equation (9).

  In other words, in the image processing device 20, in S104 of FIG. 8, the right foot portion of the direction away from the field object 12 indicated by the motion data is larger than the falling distance when the right foot portion falls at the acceleration represented by the equation (8). When the moving distance is greater, it is determined that the right foot floats. In addition, the left foot floats when the moving distance of the left foot portion away from the field object 12 indicated by the motion data is larger than the falling distance when the left foot portion falls at the acceleration shown in Expression (9). Judge. If it is determined that any of the foot portions floats with respect to the field object 12, the position of the foot portion is corrected so as to be separated from the field object 12 (S105).

  Next, in the image processing apparatus 20, the position / posture determination unit 34 determines whether or not the character object 14 jumps on the field object 12 (S106). Specifically, the position / posture determination unit 34 calculates the value of the load W applied to the gravity center position P shown in the following equation (12). If the load W is equal to or greater than 0, it is determined that a jump is possible, and if the load W is negative, it is determined that the vehicle is grounded. In particular, if the load W is −mg, it is determined that the vehicle is falling freely. In the following, W is a load applied to the center of gravity position, α is an acceleration of movement of the center of gravity position, and g is a gravitational acceleration. F is a reaction force from the field object 12 to the character object 14, m is a total weight of the character object 14, ΔV is an increment of the moving speed of the center of gravity position per one frame time, and Δt is one frame. It's time.

  Further, when the load W is 0 or more and the jump is possible, it is determined whether or not the following formula (14) is satisfied. Here, the right side is a fall distance in one frame time when the gravity center position P is freely dropped, and the left side Δv is a movement amount in the vertical direction (+ Y direction) in one frame time of the gravity center position.

  Then, it is determined that the character object 14 has jumped at a timing when the load W becomes equal to −mg from the state where the load W is equal to or greater than 0 and the expression (14) is satisfied. In this case, the center of gravity position P of the character object 14 is parabolically moved according to the following equation (15) (S107).

  Then, the position / posture determination unit 34 determines the position and posture of each part of the character object 14 according to the above processing result, thereby determining the position and posture of the character object 14 (S108). Specifically, when it is determined in S106 that the character object 14 does not jump, the position and posture of the character object 14 are determined based on the position and posture of the foot portion of the character object 14. If it is determined in S106 that the character object 14 jumps, the position and posture of the character object 14 are determined with reference to the center of gravity position P where the character object 14 parabolically moves.

  Thereafter, based on the determined position and orientation of each part, the image generation unit 36 generates an image showing the state of the virtual three-dimensional space 10, and the display unit 24 displays it (S109). Then, it waits for the arrival of the next frame timing (S110), and when it arrives, the motion data of the next frame is read from the motion data storage unit 26b (S111), and the processing after S103 is performed again based on the read motion data. Execute.

  According to the embodiment described above, the movement amount Δv of the center of gravity position P of the character object 14 is calculated based on the motion data indicating the posture change of the character object 14, and the character object 14 is changed according to the movement amount Δv. Since the position determination method is changed as appropriate, the object posture change and the position change can be linked to obtain a display of the object without a sense of incongruity.

It is a figure which shows typically the virtual three-dimensional space constructed | assembled by the image processing apparatus which concerns on embodiment of this invention. It is a figure which shows the bone structure of a character object. It is a figure which shows the master-slave relationship of the bone structure of a character object. It is a figure which shows the parts which comprise a character object. It is a figure which shows the table which memorize | stores each position and each load ratio of the parts which comprise a character object. It is a hardware block diagram of the image processing apparatus which concerns on embodiment of this invention. 1 is a functional block diagram of an image processing apparatus according to an embodiment of the present invention. It is a flow figure showing image processing (position and posture calculation processing of a character object) in an image processing device concerning an embodiment of the present invention. It is a figure which shows the method of calculating the load applied to both legs of a character object. It is a figure which shows the method of calculating the load applied to both legs of a character object.

Explanation of symbols

  10 virtual three-dimensional space, 12 field object, 14 character object, 20 image processing device, 22 calculation unit, 24 display unit, 26 storage unit, 26a object data storage unit, 26b motion data storage unit, 30 barycentric position calculation unit, 32 The center-of-gravity movement amount calculation unit, 34 position / posture determination unit, and 36 image generation unit.

Claims (5)

The posture of the object arranged on the field object in the virtual three-dimensional space is changed based on the motion data indicating the transition of the posture of the object, and the posture is changed from a given viewpoint arranged in the virtual three-dimensional space. An image processing apparatus that displays an image showing a state of viewing a virtual three-dimensional space,
Based on the motion data, a center-of-gravity position calculating unit that calculates the center-of-gravity position of the object every predetermined time;
Centroid movement amount calculating means for calculating a movement amount of the centroid position of the object per the predetermined time;
When the movement amount per predetermined time in the direction away from the field object of the barycentric position exceeds a predetermined threshold, the position of the object is determined based on the barycentric position of the object, and from the field object of the barycentric position Position determining means for determining the position of the object based on the position of the contact portion of the object with respect to the field object when the amount of movement in the direction of leaving is less than a predetermined threshold;
An image processing apparatus comprising: The image processing apparatus according to claim 1.
The position determining means performs a parabolic motion of the center of gravity position of the object in the virtual three-dimensional space when the amount of movement of the center of gravity position in a direction away from the field object per predetermined time exceeds a predetermined threshold. Determining the position of the object based on the position of the center of gravity in parabolic motion;
An image processing apparatus. The image processing apparatus according to claim 1 or 2,
The position determining means moves the contact portion in the direction away from the field object in the direction of the predetermined time when the amount of movement of the center of gravity in the direction away from the field object in the direction of the predetermined time is less than the predetermined threshold. Depending on whether the amount exceeds a predetermined threshold, the contact portion is separated from the field object;
An image processing apparatus. The posture of the object arranged on the field object in the virtual three-dimensional space is changed based on the motion data indicating the transition of the posture of the object, and the posture is changed from a given viewpoint arranged in the virtual three-dimensional space. An image processing method for displaying an image showing a state of viewing a virtual three-dimensional space,
Based on the motion data, a center-of-gravity position calculating step for calculating the center-of-gravity position of the object every predetermined time;
A center-of-gravity movement amount calculating step of calculating a movement amount of the center-of-gravity position of the object per the predetermined time;
When the movement amount per predetermined time in the direction away from the field object of the barycentric position exceeds a predetermined threshold, the position of the object is determined based on the barycentric position of the object, and from the field object of the barycentric position A position determining step of determining the position of the object based on the position of the contact portion of the object with respect to the field object when the amount of movement per predetermined time in the direction of leaving is less than a predetermined threshold;
An image processing method comprising: The posture of the object arranged on the field object in the virtual three-dimensional space is changed based on the motion data indicating the transition of the posture of the object, and the posture is changed from a given viewpoint arranged in the virtual three-dimensional space. Means for displaying an image showing a virtual three-dimensional space
Based on the motion data, a center-of-gravity position calculating unit that calculates the center-of-gravity position of the object every predetermined time;
A center-of-gravity movement amount calculation means for calculating a movement amount of the center-of-gravity position of the object per predetermined time; and a movement amount per predetermined time in a direction away from the field object of the center-of-gravity position exceeds a predetermined threshold, The position of the object is determined based on the center of gravity position of the object, and when the amount of movement of the center of gravity position in the direction away from the field object per predetermined time is less than a predetermined threshold, the position of the object is determined as A program for causing a computer to function as position determining means for determining based on the position of a contact portion with respect to the field object.

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