Stereoscopic Image Display Control Device, Imaging Apparatus Including the Same, and Stereoscopic Image Display Control Method

1. A stereoscopic image display control device which causes a stereoscopic image based on a plurality of image data photographed at different viewpoints to be displayed on a stereoscopic image display device, comprising: an enlargement instruction receiving unit that receives an enlargement instruction for enlarging the stereoscopic image displayed on the stereoscopic image display device; an enlargement display control unit that causes the stereoscopic image to be displayed in an enlarged scale according to the enlargement instruction on the stereoscopic image display device; and a parallax amount determination unit that determines, when the stereoscopic image is enlarged at a magnification according to the enlargement instruction, whether or not a parallax amount of the enlarged stereoscopic image displayed on the stereoscopic image display device is greater than a threshold value, wherein when the enlargement instruction for enlarging the stereoscopic image at the magnification at which the parallax amount is greater than the threshold value is made, the enlargement display control unit causes the enlarged stereoscopic image to be displayed on the stereoscopic image display device after the enlargement instruction is finished to become the enlarged stereoscopic image in the enlarged scale at the magnification at which the parallax amount is not greater than the threshold value.

2. The stereoscopic image display control device of claim 1 , wherein during an enlargement instruction period in which the enlargement instruction for enlarging the stereoscopic image beyond the magnification at which the parallax amount equals the threshold value is being made, the enlargement display control unit stops enlargement processing according to the enlargement instruction, and causes the enlarged stereoscopic image in the enlarged scale at the magnification at which the parallax amount equals the threshold value to be displayed on the stereoscopic image display device in a display form different from a form of the stereoscopic image in the enlarged scale at the magnification at which the parallax amount is not greater than the threshold value.

3. The stereoscopic image display control device of claim 2 , wherein the enlargement display control unit, during the enlargement instruction period, causes the enlarged stereoscopic image in the enlarged scale at the magnification at which the parallax amount equals the threshold value to be displayed in vibration within a screen of the stereoscopic image display device, or causes to be displayed in an enlarged scale and a reduced scale alternately and repeatedly.

4. The stereoscopic image display control device of claim 3 , wherein the stereoscopic image display device includes a touch panel provided on the screen, the enlargement instruction receiving unit acquires information indicating contacts of two objects on the touch panel, respective movements from contact points of the two objects, and movement destinations of the two objects, from the touch panel, and receives the enlargement instruction based on the information, and the enlargement display control unit causes, during the enlargement instruction period, causes the enlarged stereoscopic image in the enlarged scale at the magnification at which the parallax amount equals the threshold value to be displayed in vibration within the screen of the stereoscopic image display device, and acquires a movement direction starting from the contact points of the two objects from the information so that a vibration direction of the enlarged stereoscopic image within the screen substantially matches the movement direction.

5. The stereoscopic image display control device of claim 1 , wherein when the enlargement instruction for enlarging the stereoscopic image beyond the magnification at which the parallax amount equals the threshold value is made, the enlargement display control unit causes the enlarged stereoscopic image in the enlarged scale at the magnification according to the enlargement instruction to be displayed on the stereoscopic image display device during the enlargement instruction, and causes the enlarged stereoscopic image in the enlarged scale at the magnification at which the parallax amount is not greater than the threshold value to be displayed on the stereoscopic image display device when the enlargement instruction is finished.

6. The stereoscopic image display control device of claim 5 , wherein when the enlargement instruction is finished, the enlargement display control unit causes the enlarged stereoscopic image displayed on the stereoscopic image display device to be gradually reduced, and finally causes the stereoscopic image in the enlarged scale at the magnification at which the parallax amount is not greater than the threshold value to be displayed on the stereoscopic image display device.

7. The stereoscopic image display control device of claim 1 , further comprising: an observer information acquiring unit that acquires information on an observer of the stereoscopic image display device; and a threshold value setting unit that sets the threshold value according to the information on the observer acquired by the observer information acquiring unit.

8. The stereoscopic image display control device of claim 1 , further comprising: a first information display control unit that causes information indicating an allowable magnification allowing the parallax amount to be the threshold value or less to be displayed on the stereoscopic image display device.

9. The stereoscopic image display control device of claim 1 , further comprising: a second information display control unit that causes information indicating an optimum magnification allowing the parallax amount to be an optimum value for stereoscopic vision to be displayed on the stereoscopic image display device.

10. The stereoscopic image display control device of claim 1 , wherein the parallax amount of the enlarged stereoscopic image is any one of a parallax amount of a main subject included in the enlarged stereoscopic image, a maximum value of parallax amounts of subjects included in the enlarged stereoscopic image, a peak value of a histogram of the parallax amounts of the subjects included in the enlarged stereoscopic image, and an average value of the parallax amounts of the subjects included in the enlarged stereoscopic image.

11. An imaging apparatus comprising: the stereoscopic image display control device of claim 1 ; the stereoscopic image display device; an imaging unit that captures a subject; and an image processing unit that generates the plurality of image data from a plurality of image signals captured by the imaging unit.

12. A stereoscopic image display control method for causing a stereoscopic image based on a plurality of image data photographed at different viewpoints to be displayed on a stereoscopic image display device, the method comprising: an enlargement instruction receiving step of receiving an enlargement instruction for enlarging the stereoscopic image displayed on the stereoscopic image display device; an enlargement display control step of causing the stereoscopic image to be displayed in an enlarged scale according to the enlargement instruction on the stereoscopic image display device; and a parallax amount determination step of determining, when the stereoscopic image is enlarged at a magnification according to the enlargement instruction, whether or not a parallax amount of the enlarged stereoscopic image displayed on the stereoscopic image display device is greater than a threshold value, wherein in the enlargement display control step, when the enlargement instruction for enlarging the stereoscopic image at the magnification at which the parallax amount is greater than the threshold value is made, the enlarged stereoscopic image to be displayed on the stereoscopic image display device after the enlargement instruction is finished becomes the enlarged stereoscopic image in the enlarged scale at the magnification at which the parallax amount is not greater than the threshold value.