Storage medium having stored therein stereoscopic image display program, stereoscopic image display device, stereoscopic image display system, and stereoscopic image display method

1. A non-transitory computer-readable storage medium having stored therein a stereoscopic image display program to be executed by a computer of an information processing device which displays an image on a stereoscopic display device configured to produce stereoscopic display using two captured images captured by two image-capturing devices, wherein the stereoscopic image display program instructs the computer to perform:

determining a shift amount from a reference position for adjusting parallax in stereoscopic display for an area of a predetermined size representing a display range of each captured image, wherein

the two image-capturing devices capture the respective two captured images at the same time;

for at least one of the areas, if the area moved by the shift amount protrudes out of the captured image, changing the size of the area so that the area does not protrude out of the captured image; and

displaying an image in a display object area of each of the two captured images in a predetermined area on a screen of the stereoscopic display device, wherein

the display object area is the area determined by the determining a shift amount and the changing of the size of the area.

2. The non-transitory computer-readable storage medium according to claim 1 , wherein:

the stereoscopic image display program instructs the computer to further perform, for each of the captured images, a process of recognizing a predetermined image-capture object included in the captured image; and

the determining a shift amount determines the shift amount so that the moved area represents a display range such that a zero-parallax distance in stereoscopic display is a distance in accordance with a distance from the image-capturing device to the image-capture object.

3. The non-transitory computer-readable storage medium according to claim 2 , wherein:

the recognition process calculates a positional relationship between the predetermined image-capture object and each image-capturing device based on the captured image;

the stereoscopic image display program instructs the computer to further perform a distance calculation for calculating a length corresponding to a distance from the image-capturing device to the image-capture object based on at least one of the positional relationships calculated by the recognition process; and

the determining a shift amount determines the shift amount based on the zero-parallax distance determined by a distance calculated by the distance calculation.

4. The non-transitory computer-readable storage medium according to claim 3 , wherein

the displaying performs, for each captured image, a process of synthesizing an image of a virtual object produced by using the positional relationship with the captured image present in the display object area to display two images obtained by synthesis on the stereoscopic display device.

5. The non-transitory computer-readable storage medium according to claim 4 , wherein

the displaying includes:

calculating a position and an orientation of each of two virtual cameras in a virtual space where the virtual object is placed based on the corresponding positional relationship;

calculating a viewing field range of each of the virtual cameras so that the virtual space corresponding to a real space in the display object area is the range; and

producing an image of the virtual object to be synthesized with each captured image based on the position, the orientation and the viewing field of the corresponding virtual camera.

6. The non-transitory computer-readable storage medium according to claim 5 , wherein

the calculating a viewing field range calculates the viewing field range of the virtual camera so that a positional relationship of the display object area with respect to an entire area of the captured image corresponds to a positional relationship of the viewing field range to be calculated with respect to the viewing field range of the virtual camera corresponding to the viewing field range of the image-capturing device.

7. The non-transitory computer-readable storage medium according to claim 1 , wherein

when an area moved by the shift amount protrudes out of the captured image, the changing the size of the area shrinks the area so that a protruding vertex of the area is at a position on a circumference of the captured image and so that a center position thereof is not changed.

8. The non-transitory computer-readable storage medium according to claim 1 , wherein:

the determining a shift amount successively determines a shift amount for a predetermined captured image to be displayed on the stereoscopic display device among captured images successively obtained from the two image-capturing devices;

each time the shift amount is determined for the predetermined captured image, the changing the size of the area determines whether an area moved by the shift amount protrudes out of the captured image, and changes a size of the area if the area protrudes out of the captured image;

and the displaying successively displays an image in each display object area of the predetermined captured image in the predetermined area on the screen of the stereoscopic display device.

9. A stereoscopic image display configured to display an image on a stereoscopic display device configured to produce stereoscopic display using two captured images captured by two image-capturing devices, comprising one or more computer processors configured to:

determine a shift amount from a reference position for adjusting parallax in stereoscopic display for an area of a predetermined size representing a display range of each captured image, wherein

the two image-capturing devices capture the respective two captured images at the same time;

for at least one of the areas, if the area moved by the shift amount protrudes out of the captured image, change the size of the area so that the area does not protrude out of the captured image; and

display an image in a display area of each of the two captured images in a predetermined area on a screen of the stereoscopic display device using areas determined by the determining a shift amount and the change the area size as the display areas.

10. A stereoscopic image display system for displaying an image on a stereoscopic display device configured to produce stereoscopic display using two captured images captured by two image-capturing devices, comprising one or more computer processors configured to:

determine a shift amount from a reference position for adjusting parallax in stereoscopic display for an area of a predetermined size representing a display range of each captured image, wherein

the two image-capturing devices capture the respective two captured images at the same time;

for at least one of the areas, if the area moved by the shift amount protrudes out of the captured image, change the size of the area so that the area does not protrude out of the captured image; and

display an image in a display area of each of the two captured images in a predetermined area on a screen of the stereoscopic display device using areas determined by the determining a shift amount and the change the area size as the display areas.

11. The stereoscopic image display system according to claim 10 , further comprising:

a predetermined image-capture object; and one or more computer processors are further configured to

perform, for each captured image, a process of recognizing the predetermined image-capture object included in the captured image, wherein

the determining a shift amount determines the shift amount so that the moved area represents a display range such that a zero-parallax distance in stereoscopic display is a distance in accordance with a distance from the image-capturing device to the image-capture object.

12. A stereoscopic image display method for displaying an image on a stereoscopic display device configured to produce stereoscopic display using two captured images captured by two image-capturing devices, comprising:

determining a shift amount from a reference position for adjusting parallax in stereoscopic display for an area of a predetermined size representing a display range of each captured image, wherein

the two image-capturing devices capture the respective two captured images at the same time;

for at least one of the areas, if the area moved by the shift amount protrudes out of the captured image, changing the size of the area so that the area does not protrude out of the captured image; and

displaying an image in a display area of each of the two captured images in a predetermined area on a screen of the stereoscopic display device using areas determined by the determining a shift amount and the changing the area size as the display areas.