Image processing device and image processing method

1. An image processing device comprising:

a feature point derivation unit that derives a plurality of characteristic points in an input moving image obtained by photographing an object;

a tracking subject feature point setting unit that sets a feature point within a tracking subject, from the plurality of characteristic points;

a background feature point setting unit that sets a group of background feature points from the plurality of characteristic points, the background feature points not being located within the tracking subject;

a motion detection unit that detects movement over time of the background feature points within the input moving image;

a clip area setting unit that sets a size and a position of a clip area of an image to be employed such that the clip area includes the feature point within the tracking subject, on the basis of the movement of the feature point within the tracking subject and the movement of the background feature points, wherein

when the movement of the background feature points decreases or is not detected, the clip area setting unit sets the clip area in a first setting mode, and

when the movement of the background feature points is detected and does not decrease, the clip area setting unit sets the clip area in a second setting mode different from the first setting mode.

2. The image processing device of claim 1 , wherein the clip area setting unit sets, in the second setting mode, the clip area to surround the feature point within the tracking subject and the background feature points at which the movement has been detected.

3. The image processing device of claim 1 , wherein the motion detection unit further detects following feature points which follow the feature point within the tracking subject, and when the motion detection units detects that the following feature points have moved as a whole relative to the background feature points, the clip area setting unit sets the clip area to surround the feature point within the tracking subject and the following feature points such that a larger amount of space is provided in a movement direction side of the input moving image than an opposite side of the input moving image.

4. The image processing device of claim 1 , further comprising a clip area indication processing unit that indicates the clip area set by the clip area setting unit.

5. The image processing device of claim 1 , further comprising:

a clip processing unit that clips an image out of the input moving image in the clip area set by the clip area setting unit; and

a clipped image recording unit that records the image clipped by the clip processing unit.

6. An image processing method comprising:

deriving a plurality of characteristic points in an input moving image obtained by photographing an object;

setting a feature point within a tracking subject, from the plurality of characteristic points;

setting a group of background feature points from the plurality of characteristic points, the background feature points not being located within the tracking subject;

detecting movement over time of the background feature points within the input moving image; and

setting a size and a position of a clip area of an image to be employed such that the clip area includes the feature point within the tracking subject, on the basis of the movement of the feature point within the tracking subject and the movement of the background feature points, wherein

when the movement of the background feature points decreases or is not detected, the clip area is set in a first setting mode, and

when the movement of the background feature points is detected and does not decrease, the clip area is set in a second setting mode different from the first setting mode.

7. A non-transitory computer-readable storage device storing an image processing program, the image processing program instructs a computer to perform:

a feature point derivation procedure for deriving a plurality of characteristic points in an input moving image obtained by photographing an object;

a tracking subject feature point setting procedure for setting a feature point within a tracking subject, from the plurality of characteristic points;

a background feature point setting procedure for setting a group of background feature points from the plurality of characteristic points; the background feature points not being located within the tracking subject;

a motion detection procedure for detecting movement over time of the background feature points within the input moving image; and

a clip area setting procedure for setting a size and a position of a clip area of an image to be employed such that the clip area includes the feature point within the tracking subject, on the basis of the movement of the feature point within the tracking subject and the movement of the background feature points, wherein

when the movement of the background feature points decreases or is not detected, the clip area setting procedure sets the clip area in a first setting mode, and

when the movement of the background feature points is detected and does not decrease, the clip area setting procedure sets the clip area in a second setting mode different from the first setting mode.