Motion blur device, method and program

1. A motion blur control device for controlling motion blur in a specific frame image among a plurality of frame images acquired during a specific time interval, the motion blur control device comprising:

a image processing device having a processor circuit and configured to,

perform an inter-frame movement computation for computing an inter-frame movement direction and an inter-frame movement amount from the plurality of frame images acquired during the specific time interval,

perform a motion blur correction for generating a corrected frame image by correcting motion blur in the specific frame image based on a blur amount set in a range not exceeding the inter-frame movement amount and based on the inter-frame movement direction, and

perform an evaluation for evaluating the corrected frame image using a motion blur evaluation function, wherein the motion blur evaluation function includes a third order differential of the corrected frame image, wherein the blur amount is adjustable using the evaluation during blur correction such that the motion blur evaluation function satisfies a specific condition.

2. The motion blur control device of claim 1 , wherein the image processing device is configured such that the motion blur correction is to perform:

an unsharp mask setting for setting an unsharp mask based on the blur amount set in the range not exceeding the inter-frame movement amount and based on the inter-frame movement direction; and

an unsharp processing for generating the corrected frame image by correcting motion blur in the specific frame image based on the unsharp mask.

3. The motion blur control device of claim 1 , wherein the image processing device is configured such that the motion blur correction generates the corrected frame image by correcting motion blur in the specific frame image by performing deconvolution computation based on the blur amount set in the range not exceeding the inter-frame movement amount and based on the inter-frame movement direction.

4. The motion blur control device of claim 1 , wherein the image processing device is configured such that the inter-frame movement computation estimates global motion between the plurality of frame images and computes the inter-frame movement direction and the inter-frame movement amount based on affine transform parameters including a parallel movement amount and a rotation movement amount.

5. The motion blur control device of claim 4 , wherein the affine transform parameters further include an image enlargement-reduction ratio.

6. The motion blur control device of claim 1 , wherein the plurality of frame images are frame images that are components of a video image.

7. The motion blur control device of claim 1 , wherein the blur amount is changed, correction is repeatedly performed by the motion blur correction, and evaluation is repeatedly performed by the evaluation, until the motion blur evaluation function satisfies the specific condition, thereby reducing the motion blur of the specific frame image.

8. The motion blur control device of claim 7 , wherein correction is repeatedly performed by the motion blur correction and evaluation is repeatedly performed by the evaluation, until the motion blur evaluation function is a maximum value or a minimum value.

9. The motion blur control device of claim 1 , wherein the motion blur evaluation function (E) is given by the following equation:

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wherein I (x,y) is a pixel value at coordinate (x,y) in an image subject to evaluation.

10. A motion blur control method for controlling motion blur of a specific frame image among a plurality of frame images acquired during a specific time interval, the motion blur control method comprising:

computing an inter-frame movement direction and an inter-frame movement amount from the plurality of frame images acquired during the specific time interval;

generating a corrected frame image by correcting motion blur in the specific frame image based on a blur amount set in a range not exceeding the inter-frame movement amount and based on the inter-frame movement direction; and

evaluating the corrected frame image using a motion blur evaluation function, wherein the motion blur evaluation function includes a third order differential of the corrected frame image, and wherein the blur amount is adjustable during blur correction such that the motion blur evaluation function satisfies a specific condition.

11. A non-transitory computer-readable storage medium having stored thereon a set of instructions, executable by a processor, for controlling motion blur of a specific frame image among a plurality of frame images acquired during a specific time interval, the instructions comprising:

instructions for performing an inter-frame movement computation for computing an inter-frame movement direction and an inter-frame movement amount from the plurality of frame images acquired during the specific time interval;

instructions for performing a motion blur correction for generating a corrected frame image by correcting motion blur in the specific frame image based on a blur amount set in a range not exceeding the inter-frame movement amount and based on the inter-frame movement direction; and

instructions for performing an evaluation for evaluating the corrected frame image using a motion blur evaluation function, wherein the motion blur evaluation function includes a third order differential of the corrected frame image, and wherein the blur amount is adjustable during blur correction such that the motion blur evaluation function satisfies a specific condition.

12. The motion blur control device of claim 1 , wherein the motion blur evaluation function evaluates a sharpness of the corrected frame image.