Method and system for noise reduction in an image

• US 20050069221A1
• Filed: 09/29/2003
• Published: 03/31/2005
• Est. Priority Date: 09/29/2003
• Status: Active Grant

• Current Assignee: VIXS Systems Incorporated (Pixelworks Incorporated)
• Original Assignee: VIXS Systems Incorporated (Pixelworks Incorporated)
• Inventors: Zeng, Steve Zhihua
• Granted Patent: US 7,668,396 B2
• Time in Patent Office: Days
• US Class Current: 382/275
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/20221 Image fusion; Image merging
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06T 7/12 Edge-based segmentation
• CPC Class Codes: H04N 5/142 Edging; Contouring
• CPC Class Codes: H04N 5/21 Circuitry for suppressing or minimising disturbance, e.g. moiré or halo

Abstract

In a specific embodiment of the present disclosure, a source image is smoothed to create a smoothed image, and an edge detector is used to create an edge layer. A blending controller is used to control a blending between the source image and the smoothed image. The blended destination image maintains detail while eliminating unwanted noise.

Claims

1. A method comprising:

receiving a first video layer of a video image;

determining a first edge layer based on the first video layer; and

blending the first video layer with a first other layer, wherein control of the blending is based upon the first edge layer.

2. The method of claim 1, further comprising:

receiving a second video layer of the video image;

determining a second edge layer based on the second video layer; and

blending the second video layer with a second other layer, wherein the blending is controlled by the second edge layer.

3. The method of claim 2, further comprising:

providing composite of the first video layer and the second video layer for display on a display device.

4. The method of claim 1, wherein the first other layer is a filtered representation of the first video layer.

5. The method of claim 4, wherein the filtered representation is a smoothed representation of the first video layer.

6. The method of claim 1, wherein the first video layer is one of an R, G, and B layer.

7. The method of claim 1, wherein the first video layer is one of a Y, U, and V layer.

8. The method of claim 1, wherein blending is based upon a horizontal edge component.

9. The method of claim 8, wherein the blending is independent of a vertical edge component.

10. The method of claim 1, wherein blending is based upon a vertical edge component.

11. The method of claim 10, wherein the blending is independent of a horizontal edge component.

12. The method of claim 1, wherein determining the first edge layer comprises determining a gradient for a plurality of pixels of the first video layer.

13. The method of claim 12, wherein determining the first edge layer comprises determining a horizontal gradient for the plurality of pixels of the first video layer.

14. The method of claim 13, wherein determining the first edge layer comprises determining a vertical gradient for the plurality of pixels of the first video layer.

15. The method of claim 12, wherein determining the first edge layer comprises determining a vertical gradient for the plurality of pixels of the first video layer.

16. The method of claim 15, wherein the first edge layer includes an edge indicator at a pixel, when a gradient at the pixel is greater than a predefined value.

17. The method of claim 16, wherein the predefined value is user definable.

18. A method comprising:

determining an edge layer based upon an image layer;

determining a filtered layer based upon the image layer;

determining a blending ratio for each pixel of a blended image layer, wherein the blending ratio is to control blending the image layer and the filtered layer to form the blended image layer, and the blending ration is based on the edge layer.

19. The method of claim 18, wherein the filtered layer represents a smoothed image.

20. A system comprising:

a noise filter coupled to receive a source image and to provide a smoothed image;

an edge detector coupled to receive the source image and to provide an edge layer;

a blending controller coupled to receive the smoothed image and the edge layer and to provide a destination layer based upon the source layer and the destination layer.