OBJECT SPEED WEIGHTED MOTION COMPENSATED INTERPOLATION

• US 20110211124A1
• Filed: 03/01/2010
• Published: 09/01/2011
• Est. Priority Date: 03/01/2010
• Status: Active Grant

• Current Assignee: STMicroelectronics Incorporated (STMicroelectronics NV)
• Original Assignee: STMicroelectronics Incorporated (STMicroelectronics NV)
• Inventors: Petrides, Gordon
• Granted Patent: US 9,659,353 B2
• Time in Patent Office: Days
• US Class Current: 348/607
• CPC Class Codes: G06T 2207/20201 Motion blur correction
• CPC Class Codes: G06T 5/003 Deblurring; Sharpening vibration or motion blur correction for cameras comprising an electronic image sensor H04N23/682
• CPC Class Codes: G06T 5/20 using local operators
• CPC Class Codes: G06T 5/73 Deblurring; Sharpening
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51
• CPC Class Codes: H04N 7/014 involving the use of motion vectors motion estimation and compensation in video coding H04N19/51

Abstract

In one embodiment of the present invention, a method is provided for performing motion compensated interpolation using a previous frame and a current frame of a displayable output, the method comprising: detecting the speed of an object in the displayable output relative to the speed of a background in the displayable output; and blending results from a halo reducing interpolator and a median interpolator, wherein the results of each of the interpolators are weighted based on the speed of the object, to arrive at an interpolated frame using the previous frame and the current frame.

Claims

1. A method for performing motion compensated interpolation using a previous frame and a current frame of a displayable output, the method comprising:

detecting the speed of an object in the displayable output relative to the speed of a background in the displayable output; and

blending results from a halo reducing interpolator and a median interpolator, wherein the results of each of the interpolators are weighted based on the speed of the object, to arrive at an interpolated frame using the previous frame and the current frame.

2. The method of claim 1, wherein the halo reducing interpolator is configured to:

determine if motion of an object within the displayable output with respect to motion of a background within the displayable output is such that a particular area of an interpolated frame is a reveal region, a conceal region, or neither;

when the area is neither a reveal region nor a conceal region, use both forward vectors applied to the current frame and backward vectors applied to the previous frame to calculate values for pixels within the area;

when the area is a reveal region, use forward vectors applied to the current frame to calculate values for pixels within the area, without using backward vectors; and

when the area is a conceal region, use backward vectors applied to the previous frame to calculate values for pixels within the area, without using forward vectors.

3. The method of claim 1, wherein the median filter is configured to:

calculate a value for a pixel by taking the median of a pixel value generated using a corresponding forward vector applied to the current frame, a pixel value generated using a corresponding backward vector applied to the previous frame, and a temporal average pixel.

4. The method of claim 1, wherein the higher the relative speed, the higher the results of the median interpolator are weighted and the lower the results of the halo reducing interpolator are weighted.

5. The method of claim 1, further comprising generating a fade control signal based on the object speed, indicating how much to weight the result of the median interpolator and the halo reducing interpolator.

6. The method of claim 1, wherein if there is no object detected, then the results of the median interpolator are used.

7. The method of claim 1, wherein the detecting includes:

creating a two dimensional histogram of the motion vector field with dimensions corresponding to vertical and horizontal components of background and object motion vectors based on the displayable output;

giving greater weight to vectors with a higher confidence of being correct in the histogram;

analyzing the two dimensional histogram field for dominant vectors;

grouping the dominant vectors into categories, wherein one category is background and one category is object.

8. A method for performing motion compensated interpolation using a previous frame and a current frame of a displayable output, the method comprising:

detecting the speed of an object in the displayable output relative to the speed of a background in the displayable output; and

performing pre-emphasis filtering on the displayable output, wherein the pre-emphasis filtering boosts higher frequencies within the displayable output, wherein the degree of pre-emphasis filtering is weighted based on the speed of the object.

9. The method of claim 8, wherein the higher the speed of the object, the higher the degree of pre-emphasis filtering.

10. The method of claim 8, wherein the determining includes:

creating a two dimensional histogram of the motion vector field with dimensions corresponding to vertical and horizontal components of background and object motion vectors based on the displayable output;

giving greater weight to vectors with a higher confidence of being correct in the histogram;

analyzing the two dimensional histogram field for dominant vectors;

grouping the dominant vectors into categories, wherein one category is background and one category is object.

11. A method for performing motion compensated interpolation using a previous frame and a current frame of a displayable output, the method comprising:

detecting the speed of an object in the displayable output relative to the speed of a background in the displayable output;

performing pre-emphasis filtering on the displayable output, wherein the pre-emphasis filtering boosts higher frequencies within the displayable output, wherein the degree of pre-emphasis filtering is weighted based on the speed of the object; and

blending results from a halo reducing interpolator and a median interpolator, wherein the results of each of the interpolator are weighted based on the speed of the object, to arrive at an interpolated frame using the previous frame and the current frame.

12. The method of claim 11, wherein the pre-emphasis filtering is performed using a high-pass filter.

13. The method of claim 11, further comprising:

performing de-emphasis filtering after the blending in order to restore a flat frequency response.

14. An interpolation system comprising:

an object speed detection unit configured to detect the speed of an object in displayable output relative to the speed of a background in the displayable output;

a halo reducing interpolator;

a median interpolator;

a blending module coupled to the object speed detection unit, halo reducing interpolator, and median interpolator and configured to blend results of the halo reducing interpolator and the median interpolator based upon the speed of the object as detected by the object speed detection unit.

15. The interpolation system of claim 14, further comprising:

a pre-emphasis filter coupled to the halo reducing interpolator and to the median interpolator.

16. The interpolation system of claim 15, wherein the pre-emphasis filter is a high-pass filter.

17. A display device comprising:

a digital display; and

a display controller comprising;

an object speed detection unit configured to detect the speed of an object in displayable output relative to the speed of a background in the displayable output;

a halo reducing interpolator;

a median interpolator; and

a blending module coupled to the object speed detection unit, halo reducing interpolator, and median interpolator and configured to blend results of the halo reducing interpolator and the median interpolator based upon the speed of the object as detected by the object speed detection unit.

18. The display device of claim 17, wherein the display device is a television set.

19. The display device of claim 18, wherein the display device is a Liquid Crystal Display (LCD) device.

20. A computer chip configured to:

detect the speed of an object in the displayable output relative to the speed of a background in the displayable output; and

blend results from a halo reducing interpolator and a median interpolator, wherein the results of each of the interpolator are weighted based on the speed of the object, to arrive at an interpolated frame using the previous frame and the current frame.