Apparatus and method of detecting motion mask

1. An apparatus for detecting a motion mask, the apparatus comprising:

an image processor configured to generate a plurality of image frames;

a first motion mask detector configured to detect at least one first motion mask by calculating a local feature of each pixel included in a partial or entire area of at least one current image frame which indicates a pixel value relationship between the each pixel and at least one neighboring pixel, and comparing the calculated local feature with a local feature of a corresponding pixel of at least one previous image frame;

a second motion mask detector configured to detect at least one second motion mask based on a difference between the partial or entire area of the current image frame and a corresponding area of the previous image frame; and

a motion mask generator configured to generate a final motion mask comprising at least one of the first motion mask and the second motion mask.

2. The apparatus of claim 1 , wherein the first motion mask detector is further configured to exclude from the first motion mask a pixel by determining whether a difference between a maximum pixel value and a minimum pixel value from among pixel values of neighboring pixels of the pixel exceeds a preset critical value.

3. The apparatus of claim 1 , wherein a local feature of a pixel in the current image frame indicates a pixel value relationship between two pixels among the pixel and neighboring pixels of the pixel, and

wherein the first motion mask detector is further configured to detect a pixel as the first motion mask by determining whether a number of local features of the pixel, which are the same as local features of a corresponding pixel in the previous frame, is equal to or less than a preset critical value.

4. The apparatus of claim 1 , wherein the second motion mask detector is further configured to detect a pixel as the second motion mask by determining a difference between the pixel in the current image frame and a corresponding pixel in the previous image frame is equal to or greater than a preset critical value.

5. The apparatus of claim 1 , wherein the motion mask generator is configured to generate, as the final motion mask, a common area in the current image frame between the first motion mask and the second motion mask or an area comprising both the first motion mask and the second motion mask.

6. The apparatus of claim 1 , wherein the at least one current image frame comprises a plurality of current image frames captured by using different exposures, the at least one first motion mask comprises a plurality of first motion masks, and the at least one second motion mask comprises a plurality of second motion masks, and

wherein the motion mask generator is configured to generate at least one third motion mask of the plurality of current image frames based on the first motion masks and the second motion masks, and generate the final motion mask based on the at least one third motion mask.

7. The apparatus of claim 6 , wherein the plurality of current image frames comprise a first current image frame captured by using a first exposure and a second current image frame captured by using a second exposure, and

wherein the motion mask generator is further configured to generate the final motion mask comprising at least one of the third motion mask of the first current image frame and the third motion mask of the second current image frame.

8. The apparatus of claim 7 , wherein the motion mask generator is configured to generate the third motion mask of the first current image frame based on at least one of the first and second motion masks of the first current image frame, and generate the third motion mask of the second current image frame based on the first and second motion masks of the second current image frame.

9. The apparatus of claim 1 , wherein the at least one current image frame comprises first and second of current image frames captured using first and second exposure, respectively, and

wherein the at least one first motion mask comprises a first motion mask of the first current image frame and a first motion mask of the second current image frame.

10. The apparatus of claim 9 , wherein the at least one second motion mask comprises a second motion mask of the first current image frame and a second motion mask of the second current image frame.

11. The apparatus of claim 1 , wherein the plurality of image frames are downsampled image frames.

12. A method of detecting a motion mask, the method comprising:

detecting at least one first motion mask by calculating a local feature of each pixel included in a partial or entire area of at least one current image frame which indicates a pixel value relationship between the each pixel and at least one neighboring pixel, and comparing the calculated local feature with a local feature of a corresponding pixel of at least one previous image frame;

detecting at least one second motion mask based on a difference between the partial or entire area of the current image frame and a corresponding area of the previous image frame; and

generating a final motion mask comprising at least one of the first motion mask and the second motion mask.

13. The method of claim 12 , wherein the detecting the first motion mask comprises excluding from the first motion mask a pixel by determining whether a difference between a maximum pixel value and a minimum pixel value from among pixel values of neighboring pixels of the pixel exceeds a preset critical value.

14. The method of claim 12 , wherein a local feature of a pixel in the current image frame indicates a pixel value relationship between two pixels among the pixel and neighboring pixels of the pixel, and

wherein the detecting the first motion mask comprises detecting a pixel as the first motion mask by determining whether a number of local features of the pixel, which are the same as local features of a corresponding pixel in the previous frame, is equal to or less than a preset critical value.

15. The method of claim 12 , wherein the detecting the second motion mask comprises detecting a pixel as the second motion mask by determining a difference between the pixel in the current image frame and a corresponding pixel in the previous image frame is equal to or greater than a preset critical value.

16. The method of claim 12 , wherein the generating the final motion mask comprises generating, as the final motion mask, a common area in the current image frame between the first motion mask and the second motion mask or an area comprising both the first motion mask and the second motion mask.

17. The method of claim 12 , wherein the at least one current image frame comprises a plurality of current image frames captured by using different exposures, the at least one first motion mask comprises a plurality of first motion masks, and the at least one second motion mask comprises a plurality of second motion masks, and

wherein the generating the final motion mask comprises generating at least one third motion mask of the plurality of current image frames based on the first motion masks and the second motion masks, and generating the final motion mask based on the at least one third motion mask.

18. The method of claim 12 , wherein the plurality of current image frames comprise a first current image frame captured at a first exposure level and a second current image frame captured at a second exposure level, and

wherein the generating the final motion mask comprises generating the final motion mask comprising at least one of the third motion mask of the first current image frame and the third motion mask of the second current image frame.

19. The method of claim 18 , wherein the generating the at least one third motion mask comprises:

generating the third motion mask of the first current image frame based on at least one of the first and second motion masks of the first current image frame; and

generating the third motion mask of the second current image frame based on the first and second motion masks of the second current image frame.

20. The method of claim 12 , wherein the at least one current image frame comprises first and second of current image frames captured using first and second exposure, respectively,

wherein the at least one first motion mask comprises a first motion mask of the first current image frame and a first motion mask of the second current image frame, and

wherein the at least one second motion mask comprises a second motion mask of the first current image frame and a second motion mask of the second current image frame.