Image processing apparatus, image capturing apparatus, and computer program

1. An image processing apparatus for generating an interpolation frame that is inserted between a first frame and a second frame of a moving picture contiguous with each other, the image processing apparatus comprising:

a repetitive pattern detection section configured to detect whether a repetitive pattern is present in at least one of the first and second frames;

a motion vector calculation section configured to calculate a motion vector by performing a matching operation between the first and second frames within a search range determined according to a detection result from the repetitive pattern detection section; and

an interpolation frame generation section configured to generate the interpolation frame in accordance with a calculation result of the motion vector.

2. The image processing apparatus of claim 1 , wherein the motion vector calculation section sets a first search range as the search range when the detection result from the repetitive pattern detection section indicates that the repetitive pattern is present in at least one of the first and second frames, and the motion vector calculation section sets a second search range different from the first search range as the search range when the detection result from the repetitive pattern detection section indicates that the repetitive pattern is absent in either one of the first and second frames.

3. The image processing apparatus of claim 2 , wherein:

the repetitive pattern detection section further detects a repetition cycle based on the detection result from the repetitive pattern; and

the first search range is determined so as to be less than or equal to a repetition cycle in a first direction in which the pattern repeats.

4. The image processing apparatus of claim 3 , further comprising a storage section configured to store information representing the search range for a motion vector,

wherein the second search range is set based on the information.

5. The image processing apparatus of claim 3 , wherein the motion vector calculation section calculates the motion vector while further limiting the search range so as to be less than or equal to a repetition cycle of the repetitive pattern in a second direction different from the first direction.

6. The image processing apparatus of claim 5 , wherein the first direction is a horizontal direction of an image represented by each frame, and the second direction is a vertical direction of an image represented by each frame.

7. The image processing apparatus of claim 1 , wherein:

the motion vector calculation section divides each of the first and second frames into a plurality of portions, and performs a matching operation between the first and second frames for each of the divided portions to calculate the motion vector for the portion; and

the interpolation frame generation section generates the interpolation frame based on the motion vector calculated for each of the portions.

8. An image capturing apparatus comprising:

the image processing apparatus of claim 1 ; and

an image capturing section configured to generate data of a moving picture including the first and second frames through a shooting.

9. A computer program, stored on a non-transitory computer-readable medium, for use in an image processing apparatus for generating an interpolation frame that is inserted between a first frame and a second frame of a moving picture contiguous with each other, the computer program instructing a computer of the image processing apparatus to execute the steps of:

detecting whether a repetitive pattern is present in at least one of the first and second frames;

calculating a motion vector by performing a matching operation between the first and second frames within a search range determined according to a detection result from the repetitive pattern detection section; and

generating the interpolation frame in accordance with a calculation result of the motion vector.