Skin and sky color detection and enhancement system

• US 20100322513A1
• Filed: 06/19/2009
• Published: 12/23/2010
• Est. Priority Date: 06/19/2009
• Status: Abandoned Application

• Current Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Xu, Xinyu, Pan, Hao
• Application Number:
  US12/456,604
• Publication Number:
  US 20100322513A1
• Time in Patent Office: Days
• US Class Current: 382/167
• CPC Class Codes: G06T 2207/10024 Color image
• CPC Class Codes: G06T 2207/20081 Training; Learning
• CPC Class Codes: G06T 2207/20224 Image subtraction
• CPC Class Codes: G06T 2207/30088 Skin; Dermal
• CPC Class Codes: G06T 5/20 using local operators

Abstract

An image enhancement technique that includes a filter that receives an image and generates a filtered image primarily including lower frequency content and sharp edges of the image. A skin color processing is based upon the filtered image to enhance skin tone regions of the image. A sky color processing is based upon the filtered image to enhance sky color regions of the image. A combiner calculates an output image based upon the skin color processing, the sky color processing, and higher frequency content of the image.

Claims

1. A image enhancement technique comprising:

(a) a filter receives said image and generates a filtered image primarily including lower frequency content and sharp edges of said image;

(b) a skin color processing that based upon said filtered image enhances skin tone regions of said image;

(c) a sky color processing that based upon said filtered image enhances sky color regions of said image;

(d) a combiner that calculates an output image based upon said skin color processing, said sky color processing, and higher frequency content of said image.

2. The technique of claim 1 wherein said filter is a sieve filter.

3. The technique of claim 1 wherein the color gamut of said image is smaller than the output gamut of said output image.

4. The technique of claim 3 wherein said image has a sRGB color gamut.

5. The technique of claim 1 wherein said higher frequency content is determined based upon said filtered image and said image.

6. The technique of claim 1 wherein said skin color processing is based upon a skin color look up table.

7. The technique of claim 1 wherein said skin color processing is based upon a sky color look up table.

8. The technique of claim 1 wherein sky color processing is based upon the results of said skin color processing.

9. The technique of claim 1 wherein said sky color processing is not based upon the results of said skin color processing.

10. The technique of claim 1 wherein said skin color processing is based upon a skin color look up table, said skin color processing is based upon a sky color look up table, and where said skin color look up table is substantially non-overlapping with said sky color look up table.

11. The technique of claim 6 wherein said look up table is pre-computed.

12. The technique of claim 7 wherein said look up table is pre-computed.