Image processing apparatus and image processing method
An image processing apparatus according to the present invention, comprises: a motion detection unit that detects a motion vector from an input image; a determination unit that determines whether an image is moving in each pixel in use of the detected motion vector, and determines whether a motion pixel, about which determination has been made that the image is moving therein, exists in a predetermined range from a still pixel about which determination has been made that the image is not moving therein; and a correction unit that performs correction processing to decrease at least one of high frequency components, contrast, and luminance for the still pixel about which determination has been made that a motion pixel exists in the predetermined range.
1. An image processing apparatus comprising:
a motion detection unit that detects a motion from an input image;
a determination unit that determines whether a distance between a motion pixel in which the image is moving and a still pixel in which the image is not moving is shorter than a predetermined distance based on a detection result of the motion detection unit; and
a correction unit that performs correction processing to decrease at least one of high frequency components, contrast, and luminance for the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance by the determination unit when a frequency distribution of an area to which the still pixel belongs is concentrated to a specific frequency.
2. The image processing apparatus according to claim 1 , further comprising,
a frequency distribution calculation unit that divides a frame image that includes a correction target pixel into a plurality of sub-areas, and calculates, for each of the sub-areas, the frequency distribution in use of a still pixel located in the sub-area, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance, wherein
the correction unit performs the correction processing for the correction target pixel when the frequency distribution of a sub-area to which this correction target pixel belongs is concentrated to the specific frequency.
3. The image processing apparatus according to claim 1 , further comprising a luminance value calculation unit that divides a frame image that includes a correction target pixel into a plurality of sub-areas, and calculates, for each of the sub-areas, a luminance value in use of a still pixel located in each of the sub-areas, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance, wherein
the correction unit performs the correction processing for the correction target pixel when a luminance value of a sub-area, to which this correction target pixel belongs, is higher than a predetermined luminance value.
4. The image processing apparatus according to claim 1 , wherein the correction unit increases a correction degree in the correction processing as a distance between a correction target pixel and the motion pixel is shorter, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance.
5. The image processing apparatus according to claim 1 , further comprising a motion area determination unit that determines whether a plurality of motion areas, where an image is moving, exist or not in a frame image including a correction target pixel, based on the motion of the image for each of the pixels, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance, wherein
the correction unit does not perform the correction processing when a plurality of motion areas exist in the frame image.
6. The image processing apparatus according to claim 1 , wherein the correction unit increases a correction degree in the correction processing as a screen of a display apparatus which displays the input image is larger.
7. The image processing apparatus according to claim 1 , further comprising a detection unit that detects a viewer of the input image, wherein
the correction unit increases a correction degree in the correction processing as a distance between a display apparatus which displays the input image and the viewer is shorter.
8. The image processing apparatus according to claim 1 , further comprising a pan determination unit that determines whether the input image is a panned image or not based on the detection result of the motion detection unit, wherein
the correction unit does not perform the correction processing when the input image is a panned image.
9. The image processing apparatus according to claim 1 , wherein
the motion detection unit detects a motion vector from an input image,
the correction processing is filter processing, and
the correction unit sets to 0 a filter coefficient, which corresponds to a pixel of which magnitude of a motion vector is larger than a predetermined threshold, out of peripheral pixels located around a correction target pixel, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance.
10. The image processing apparatus according to claim 1 , wherein
the motion detection unit detects a motion vector from an input image,
the correction processing is filter processing, and
the correction unit performs the filter processing using a filter which has a greater number of taps as a magnitude of the motion vector of the motion pixel, which has been determined to exist in the predetermined range, is larger.
11. The image processing apparatus according to claim 1 , wherein
the motion detection unit detects a motion vector from an input image,
the correction processing is filter processing, and
the correction unit performs the filter processing using a filter in which taps are arrayed in a direction according to a direction of the motion vector of a motion pixel which has been determined to exist in the predetermined range.
12. An image processing method comprising:
a motion detection step of detecting a motion from an input image;
a determination step of determining whether a distance between a motion pixel in which the image displayed on said display apparatus is moving and a still pixel in which the image displayed on said display apparatus is not moving is shorter than a predetermined distance based on a detection result of the motion detection step; and
a correction step of performing correction processing to decrease at least one of high frequency components, contrast, and luminance for the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance by the determination step when a frequency distribution of an area to which the still pixel belongs is concentrated to a specific frequency.
13. The image processing apparatus according to claim 1 , further comprising,
a frequency distribution calculation unit that calculates the frequency distribution of a frame image that includes a correction target pixel, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance, wherein
the correction unit performs the correction processing for the correction target pixel when the frequency distribution of the frame image that includes the correction target pixel is concentrated to the specific frequency.
14. The image processing method according to claim 12 , further comprising,
a frequency distribution calculation step of dividing a frame image that includes a correction target pixel into a plurality of sub-areas, and calculating, for each of the sub-areas, the frequency distribution in use of a still pixel located in the sub-area, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance, wherein
in the correction step, the correction processing is performed for the correction target pixel when the frequency distribution of a sub-area to which this correction target pixel belongs is concentrated to the specific frequency.
15. The image processing method according to claim 12 , further comprising a luminance value calculation step of dividing a frame image that includes a correction target pixel into a plurality of sub-areas, and calculating, for each of the sub-areas, a luminance value in use of a still pixel located in each of the sub-areas, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance, wherein
in the correction step, the correction processing is performed for the correction target pixel when a luminance value of a sub-area, to which this correction target pixel belongs, is higher than a predetermined luminance value.
16. The image processing method according to claim 12 , wherein in the correction step, a correction degree in the correction processing is increased as a distance between a correction target pixel and the motion pixel is shorter, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance.
17. The image processing method according to claim 12 , further comprising a motion area determination step of determining whether a plurality of motion areas, where an image is moving, exist or not in a frame image including a correction target pixel, based on the motion of the image for each of the pixels, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance, wherein
in the correction step, the correction processing is not performed when a plurality of motion areas exist in the frame image.
18. The image processing method according to claim 12 , wherein in the correction step a correction degree in the correction processing is increased as a screen of a display apparatus which displays the input image is larger.
19. The image processing method according to claim 12 , further comprising a detection step of detecting a viewer of the input image, wherein
in the correction step, a correction degree in the correction processing is increased as a distance between a display apparatus which displays the input image and the viewer is shorter.
20. The image processing method according to claim 12 , further comprising a pan determination step of determining whether the input image is a panned image or not based on the detection result of the motion detection step, wherein
in the correction step, the correction processing is not performed when the input image is a panned image.
21. The image processing method according to claim 12 , wherein
in the motion detection step, a motion vector is detected from an input image,
the correction processing is filter processing, and
in the correction step, a filter coefficient, which corresponds to a pixel of which magnitude of a motion vector is larger than a predetermined threshold, out of peripheral pixels located around a correction target pixel is set to 0, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance.
22. The image processing method according to claim 12 , wherein
in the motion detection step, a motion vector is detected from an input image,
the correction processing is filter processing, and
in the correction step, the filter processing is performed using a filter which has a greater number of taps as a magnitude of the motion vector of the motion pixel, which has been determined to exist in the predetermined range, is larger.
23. The image processing method according to claim 12 , wherein
in the motion detection step, a motion vector is detected from an input image,
the correction processing is filter processing, and
in the correction step, the filter processing is performed using a filter in which taps are arrayed in a direction according to a direction of the motion vector of a motion pixel which has been determined to exist in the predetermined range.
24. The image processing method according to claim 12 , further comprising,
a frequency distribution calculation step of calculating the frequency distribution of a frame image that includes a correction target pixel, the correction target pixel being the still pixel about which determination has been made that a distance from a motion pixel is shorter than the predetermined distance, wherein
in the correction step, the correction processing is performed for the correction target pixel when the frequency distribution of the frame image that includes the correction target pixel is concentrated to the specific frequency.
25. An image processing apparatus comprising:
a motion detection unit that detects a motion from an input image;
a correction unit that performs correction processing to decrease at least one of high frequency components, contrast, and luminance for a still pixel, in which the image is not moving, near a motion pixel in which the image is moving, when a frequency distribution of an area to which the still pixel belongs having a specific cyclic pattern.
26. An image processing method comprising:
detecting, by a motion detection unit, a motion from an input image; and
performing, by a correction unit, correction processing to decrease at least one of high frequency components, contrast, and luminance for a still pixel, in which the image is not moving, near a motion pixel in which the image is moving, when a frequency distribution of an area to which the still pixel belongs having a specific cyclic pattern.