VR sickness reduction system, head-mounted display, VR sickness reduction method, and program

1 . A system comprising:

one or more processors; and

one or more computer readable storage media storing instructions that, when executed by the one or more processors, cause the system to perform operations comprising:

generating, on a display section of a head-mounted display, moving image data corresponding to a moving image, wherein the moving image represents a state of a virtual space from a virtual camera positioned in the virtual space;

determining an acceleration status of the head-mounted display, wherein the acceleration status indicates a state in which a point of view in a frame image of the moving image data is accelerated and is based at least in part on whether the virtual camera is accelerating in the virtual space;

determining a distance between a position of a virtual object in the frame image and a position of the virtual camera providing the point of view;

determining a total difference for all pixel values in the frame image and a preceding frame image; and

generating rocking control data to control a rocking of a rocking section of the head-mounted display based at least in part on the acceleration status, the total difference, and a change in the distance, wherein controlling the rocking includes changing the rocking when the total difference changes from the preceding frame image to the frame image.

2 . The system of claim 1 , the operations further comprising:

determining, based at least in part on the rocking control data, whether or not the point of view of the frame image is accelerating;

generating rocking control moving image data comprising the moving image data and the rocking control data, the frame image in the moving image being determined on a basis of the rocking control data, the frame image corresponding to the point of view that is being accelerated; and

controlling whether or not to control rocking of the rocking section depending on a result of the determination of whether or not the point of view of the frame image is accelerating.

3 . The system of claim 2 , wherein the rocking control moving image data includes the moving image data, and wherein the moving image data indicates that the moving image represents a state of a virtual space viewed from the virtual camera positioned in the virtual space, and wherein the rocking control data is generated based at least in part on the result of the determining whether or not the point of view of the frame image is accelerating.

4 . The system of claim 1 , wherein the rocking control data is based at least in part on the distance between the virtual camera and the virtual object closest to the point of view of the virtual camera.

5 . The system of claim 1 , wherein the rocking control data controls an amount of rocking of the rocking section based at least in part on the distance between the virtual camera and the virtual object positioned in the virtual space.

6 . The system of claim 1 , wherein the rocking control data is based at least in part on an amount of movement of the virtual object in the moving image per unit time.

7 . The system of claim 6 , wherein controlling the rocking of the rocking section based at least in part on the amount of movement of the virtual object in the moving image per unit time.

8 . The system of claim 1 , the operations further comprising:

acquiring rocking control moving image data including moving image data indicating the moving image and rocking control data;

determining an acceleration status of the point of view in the frame image; and

determining, based at least in part on the rocking control data included in the rocking control moving image data, the acceleration status of the point of view in the frame image displayed on the head-mounted display, and wherein modifying the rocking of the rocking section based on the determination of the acceleration status.

9 . The system of claim 1 , wherein the rocking section is provided on a front surface of a housing of a head-mounted display, wherein the rocking section is positioned within the head-mounted display such that when the head-mounted display is worn by a user, the rocking section is in physical contact with a forehead of the user.

10 . The system of claim 9 , wherein the acceleration status is determined based at least in part on a movement of the head-mounted display.

11 . The system of claim 1 , wherein the operations further comprise:

modifying an amount of the rocking of the rocking section by increasing the amount of rocking based on the distance being less than a predetermined distance.

12 . The system of claim 1 , wherein the operations further comprise:

modifying an amount of the rocking of the rocking section by decreasing the amount of rocking based on the distance being equal to or greater than a predetermined distance.

13 . The system of claim 1 , wherein the operations further comprise:

determining a difference between a pixel value of a first pixel in the frame image and a pixel value for a second pixel in the preceding frame image, wherein controlling the rocking is further based on the difference, the first pixel being the same as the second pixel.

14 . The system of claim 13 , wherein controlling the rocking further comprises:

i) increasing the rocking if the total difference increases from the preceding frame image to the frame image; or

ii) decreasing the rocking if the total difference decreases from the preceding frame image to the frame image.

15 . The system of claim 1 , further comprising: a sensor section configured to output orientation, an amount of rotation, or an amount of movement of the system.

16 . The system of claim 1 , wherein the rocking section includes a vibration motor, wherein the operations further comprise:

controlling the vibration motor to vibrate in response to the rocking control data in a frequency band between 10 Hz and 20 Hz and an acceleration value between 0.05 G to 0.5 G.

17 . A method comprising:

generating, on a display section of a head-mounted display, moving image data corresponding to a moving image, wherein the moving image represents a state of a virtual space;

determining an acceleration status of the head-mounted display, wherein the acceleration status indicates a state in which a point of view in a frame image of the moving image data is accelerated and is based at least in part on whether a virtual camera is accelerating in the virtual space;

determining a distance between a position of a virtual object in the frame image and a position of the virtual camera providing the point of view;

determining a total difference for all pixel values in the frame image and a preceding frame image; and

generating rocking control data to control a rocking of a rocking section of the head-mounted display based at least in part on the acceleration status, the total difference, and a change in the distance, wherein controlling the rocking includes changing the rocking when the total difference changes from the preceding frame image to the frame image.

18 . The method of claim 17 , further comprising:

determining a difference between a pixel value of a first pixel in the frame image and a pixel value for a second pixel in the preceding frame image, wherein controlling the rocking is further based on the difference, the first pixel being the same as the second pixel, and wherein controlling the rocking further comprises:

i) increasing the rocking if the total difference increases from the preceding frame image to the frame image; or

ii) decreasing the rocking if the total difference decreases from the preceding frame image to the frame image.

19 . A non-transitory, computer readable storage medium containing a computer program, which when executed by a computer, causes the computer to perform a virtual sickness reduction method by carrying out actions, comprising:

generating, on a display section of a head-mounted display, moving image data corresponding to a moving image, wherein the moving image represents a state of a virtual space from a virtual camera positioned in the virtual space;

determining an acceleration status of the head-mounted display, wherein the acceleration status indicates a state in which a point of view in a frame image of the moving image data is accelerated and is based at least in part on whether the virtual camera is accelerating in the virtual space;

determining a distance between a position of a virtual object in the frame image and a position of the virtual camera providing the point of view;

determining a total difference for all pixel values in the frame image and a preceding frame image; and

generating rocking control data to control a rocking of a rocking section of the head-mounted display based at least in part on the acceleration status, the total difference, and a change in the distance, wherein controlling the rocking includes changing the rocking when the total difference changes from the preceding frame image to the frame image.

20 . The non-transitory, computer readable storage medium of claim 19 , wherein executing the computer program further causes the computer to:

determining a difference between a pixel value of a first pixel in the frame image and a pixel value for a second pixel in the preceding frame image, wherein controlling the rocking is further based on the difference, the first pixel being the same as the second pixel, and wherein controlling the rocking further comprises:

ii) increasing the rocking if the total difference increases from the preceding frame image to the frame image; or

ii) decreasing the rocking if the total difference decreases from the preceding frame image to the frame image.