Methods and systems for sub-pixel rendering with gamma adjustment

1. A method of converting input image data in a first format indicating an image for rendering on a display panel comprising a plurality of sub-pixels arranged in a second format, the method comprising:

receiving input image data including a plurality of first data values indicating the image, each of the first data values representing a data point in one of a plurality of primary colors in the image;

performing a gamma correction operation on said first data values in the input image data to produce gamma-corrected data for each first data value;

performing a sub-pixel rendering operation using the gamma-corrected data to produce sub-pixel rendered image data comprising a plurality of second data values, each of the second data values indicating a color value for one of said sub-pixels on said display panel, wherein said sub-pixel rendering operation comprises performing an area resampling operation to produce each said second data value; said area resampling operation multiplying a plurality of first data values indicating a first area of said image using a filter kernel comprising a plurality of coefficients to produce a plurality of products; said second data value comprising a sum of said products; and

rendering said sub-pixel rendered image data on said display panel to produce said image.

2. The method of claim 1 , wherein performing said gamma correction operation implements the function g −1 (x)=x y where x is equal to one of said first data values and where y substantially represents the response of the human eye to luminance of pixels in the display panel.

3. The method of claim 1 , wherein performing said gamma correction operation implements a function that compensates for a response function of human eyes to luminance.

4. The method of claim 1 , further comprising performing a post-gamma correction operation on said sub-pixel rendered image data wherein said post-gamma correction operation compensates for a gamma function with which the display panel is equipped.

5. The method of claim 1 , wherein each of said plurality of sub-pixels has one of said plurality of primary colors of said image, and wherein performing said sub-pixel rendering operation comprises:

determining an implied sample area in the input image representing each said first data value to produce an implied sample area array indicating said image;

for each sub-pixel on said display panel having a first one of said plurality of primary colors, determining a resample area comprising a resample point representing said sub-pixel;

a plurality of said resample areas for said first one of said plurality of primary colors forming a first primary color resample area array;

positioning said first primary color resample area array over said implied sample area array such that each resample area overlays a target plurality of implied sample areas; and

computing said second data value for each resample point using said first data values represented by said target plurality of implied sample areas.

6. The method of claim 5 , wherein computing said second data value for each resample point comprises:

selecting a filter kernel comprising a plurality of coefficient terms;

multiplying said gamma-corrected data for each first data value included in said target plurality of implied sample areas by one of the coefficient terms in the filter kernel to produce a product; and

adding said products to produce said second data value.

7. The method of claim 1 , wherein said sub-pixels are arranged on the display panel in a matrix of a plurality of a sub-pixel repeating group comprising first and second rows of sub-pixels in at least first and second primary colors; and wherein a sub-pixel of a first primary color follows a sub-pixel of a second primary color in said first row of said sub-pixel repeating group and a sub-pixel of a second primary color follows a sub-pixel of a first primary color in said second row of said sub-pixel repeating group.

8. A computer-readable medium storing instructions; said instructions when executed by a processor causing the processor to convert input image data in a first format indicating an image for rendering on a display panel comprising a plurality of sub-pixels arranged in a second format; said instructions when executed by a processor performing a method comprising:

receiving input image data including a plurality of first data values indicating the image, each of the first data values representing a data point in one a plurality of primary colors in the image;

performing a gamma correction operation on said first data values in the input image data to produce gamma-corrected data for each first data value;

performing a sub-pixel rendering operation using the gamma-corrected data to produce sub-pixel rendered image data comprising a plurality of second data values, each of the second data values indicating a color value for one of said sub-pixels on said display panel, wherein said sub-pixel rendering operation comprises performing an area resampling operation to produce each said second data value; said area resampling operation multiplying a plurality of first data values indicating a first area of said image using a filter kernel comprising a plurality of coefficients to produce a plurality of products; said second data value comprising a sum of said products; and

rendering said sub-pixel rendered image data on said display panel to produce said image.

9. A method of converting input image data in a first format indicating an image for rendering on a display panel comprising a plurality of sub-pixels arranged in a second format, the method comprising:

receiving input image data including a plurality of first data values indicating the image, each of the first data values representing a data point in one of a plurality of primary colors in the image;

performing a gamma correction operation on said first data values in the input image data to produce gamma-corrected data for each first data value;

performing a sub-pixel rendering operation using the gamma-corrected data to produce sub-pixel rendered image data comprising a plurality of second data values, each of the second data values indicating a color value for one of said sub-pixels on said display panel;

rendering said sub-pixel rendered image data on said display panel to produce said image; and

wherein further each of said plurality of sub-pixels has one of said plurality of primary colors of said image, and wherein performing said sub-pixel rendering operation comprises:

determining an implied sample area in the input image representing each said first data value to produce an implied sample area array indicating said image;

for each sub-pixel on said display panel having a first one of said plurality of primary colors, determining a resample area comprising a resample point representing said sub-pixel;

a plurality of said resample areas for said first one of said plurality of primary colors forming a first primary color resample area array;

positioning said first primary color resample area array over said implied sample area array such that each resample area overlays a target plurality of implied sample areas; and

computing said second data value for each resample point using said first data values represented by said target plurality of implied sample areas.

10. The method of claim 9 , wherein computing said second data value for each resample point comprises:

selecting a filter kernel comprising a plurality of coefficient terms;

multiplying said gamma-corrected data for each first data value included in said target plurality of implied sample areas by one of the coefficient terms in the filter kernel to produce a product; and

adding said products to produce said second data value.

11. A method of converting input image data in a first format indicating an image for rendering on a display panel comprising a plurality of sub-pixels arranged in a second format, the method comprising:

receiving input image data including a plurality of first data values indicating the image, each of the first data values representing a data point in one of a plurality of primary colors in the image;

performing a gamma correction operation on said first data values in the input image data to produce gamma-corrected data for each first data value;

performing a sub-pixel rendering operation using the gamma-corrected data to produce sub-pixel rendered image data comprising a plurality of second data values, each of the second data values indicating a color value for one of said sub-pixels on said display panel, wherein said sub-pixel rendering operation comprises performing an area resampling operation to produce each of said second data values, said area resampling operation multiplying a plurality of first data values indicating a first area of said image using a filter kernel comprising a plurality of coefficients to produce a plurality of products, said second data values comprising a sum of said products;

rendering said sub-pixel rendered image data on said display panel to produce said image; and

wherein further performing said gamma correction operation implements the function

g −1 (x)=x y where x is equal to one of said first data values and where y substantially represents the response of the human eye to luminance of pixels in said display panel.

12. The method of claim 11 , wherein said sub-pixels are arranged on the display panel in a matrix of a plurality of a sub-pixel repeating groups each comprising first and second rows of sub-pixels in at least first and second primary colors, and wherein, within each sub-pixel repeating group, a sub-pixel of a first primary color follows a sub-pixel of a second primary color in said first row and a sub-pixel of a second primary color follows a sub-pixel of a first primary color in said second row.

13. A method of converting input image data in a first format indicating an image for rendering on a display panel comprising a plurality of sub-pixels arranged in a second format, the method comprising:

receiving input image data including a plurality of first data values indicating the image, each of the first data values representing a data point in one of a plurality of primary colors in the image;

performing a gamma correction operation on said first data values in the input image data to produce gamma-corrected data for each first data value;

performing a sub-pixel rendering operation using the gamma-corrected data to produce sub-pixel rendered image data comprising a plurality of second data values, each of the second data values indicating a color value for one of said sub-pixels on said display panel, wherein said sub-pixel rendering operation comprises performing an area resampling operation to produce each of said second data values, said area resampling operation multiplying a plurality of first data values indicating a first area of said image using a filter kernel comprising a plurality of coefficients to produce a plurality of products, said second data values comprising a sum of said products;

performing a post-gamma correction operation on said sub-pixel rendered image data wherein said post-gamma correction operation compensates for a gamma function with which the display panel is equipped; and

rendering said sub-pixel rendered image data on said display panel to produce said image.

14. The method of claim 13 , wherein said sub-pixels are arranged on the display panel in a matrix of a plurality of sub-pixel repeating groups each comprising first and second rows of sub-pixels in at least first and second primary colors, and wherein, within a sub-pixel repeating group, a sub-pixel of a first primary color follows a sub-pixel of a second primary color in said first row and a sub-pixel of a second primary color follows a sub-pixel of a first primary color in said second row.