Artifact removal method and system for contoured images and video

1. A system for removing a compression artifact of a step contour from an original piece of content having a gradient, the system comprising:

an artifact removal unit implemented on a computer system that restores a gradient to a piece of content having a gradient by removing a step contour artifact;

the artifact removal unit detects a start of a step contour and an end of a step contour in each row of the piece of content, determines a gradient of the step contour in each row and increments a pixel in certain regions of the row; and

the artifact removal unit detects a start of a step contour and an end of a step contour in each column of the piece of content, determines a gradient of the step contour in each column and increments a pixel in certain regions of the column to restore the gradient in the piece of content.

2. The system of claim 1 , wherein the artifact removal unit increments the pixel in certain region of the row by multiplying a position of the pixel relative to a start of the row by a determined gradient for the row.

3. The system of claim 1 , wherein the artifact removal unit increments the pixel in certain region of the column by multiplying a position of the pixel relative to a start of the column by a determined gradient for the column.

4. The system of claim 1 , wherein the artifact removal unit detects the start of the step contour by detecting a first pair of pixels scanned with a difference of one of N and 0.

5. The system of claim 1 , wherein the artifact removal unit detects the end of the step contour by detecting a first pair of pixels where the difference of the pixels is one of Not 0 or N and a direction of the difference has changed.

6. The system of claim 1 , wherein the artifact removal unit further comprises a plurality of lines of computer code.

7. The system of claim 1 , wherein the piece of content is one of an image, a color image and a video frame.

8. The system of claim 7 , wherein the color image is an image for each color that makes up the color image.

9. The system of claim 7 , wherein the video frame is a series of images.

10. A method for removing a compression artifact of a step contour from an original piece of content having a gradient, the method comprising:

detecting a start of a step contour and an end of a step contour in each row of a piece of content having a gradient;

determining a gradient of the step contour in each row;

incrementing a pixel in certain regions of the row;

detecting a start of a step contour and an end of a step contour in each column of the piece of content;

determining a gradient of the step contour in each column; and

incrementing a pixel in certain regions of the column to restore the gradient in the piece of content.

11. The method of claim 10 , wherein incrementing the pixel in certain region of the row further comprising multiplying a position of the pixel relative to a start of the row by a determined gradient for the row.

12. The method of claim 10 , wherein incrementing the pixel in certain region of the column further comprises multiplying a position of the pixel relative to a start of the column by a determined gradient for the column.

13. The method of claim 10 , wherein detecting the start of the step contour further comprises detecting a first pair of pixels scanned with a difference of one of N and 0.

14. The method of claim 10 , wherein detecting the end of the step contour further comprises detecting a first pair of pixels where the difference of the pixels is one of Not 0 or N and a direction of the difference has changed.

15. The method of claim 10 , wherein the piece of content is one of an image, a color image and a video frame.

16. The method of claim 15 , wherein the color image is an image for each color that makes up the color image.

17. The method of claim 16 , wherein the video frame is a series of images.