Type size dependent anti-aliasing in sub-pixel precision rendering systems

In a processing device associated with a display device that has a plurality of pixels, each pixel having a plurality of separately controllable pixel sub-components, a method of applying selected anti-aliasing filters when rendering an image, comprising the acts of:

• based on a first font size of a first character to be displayed, selecting a first anti-aliasing filter;
• applying the first anti-aliasing filter to the first character;
• based on a second font size of a second character to be displayed, selecting a different second anti-aliasing filter, wherein the second font size is larger than the first font size;
• applying the second anti-aliasing filter to the second character;
• and
• displaying the first character on the display device, wherein spatially different sets of samples obtained by applying the first filter are mapped to individual pixel subcomponents;
• and
• displaying the second character on the display device, wherein spatially different sets of samples obtained by applying the second anti-aliasing filter are mapped to individual pixel sub-components.

In a processing device associated with a display device that has a plurality of pixels, each pixel having a plurality of separately controllable pixel sub-components, a method of rendering an image using an anti-aliasing filter selected from a plurality of anti-aliasing filters based on the font size of a character of the image, comprising the acts of:

• storing a data structure that defines a plurality of different anti-aliasing filters;
• identifying the attributes of an object of the image to be rendered;
• selecting, based on the identified attributes, an anti-aliasing filter from among the plurality of different anti-aliasing filters, wherein at least two of the plurality of different anti-aliasing filters operates by calculating a weighted sum of adjacent samples of image data that represents the image;
• and
• applying the selected anti-aliasing filter in a direction parallel to striping of the pixel sub-components.

In a processing device associated with a display device that has a plurality of pixels, each pixel having a plurality of separately controllable pixel sub-components, a method of selecting an anti-aliasing filter during the rendering of an image from image data, comprising the act of:

• mapping spatially different sets of samples of the image data to different pixel sub-components of individual pixels in preparation for displaying the image with pixel sub-component precision in a first direction;
• identifying the font size of the image to be rendered;
• selecting an anti-aliasing filter from a plurality of different anti-aliasing filters based on the font size of a character of the image;
• and
• applying the anti-aliasing filter in a second direction orthogonal to the first direction.

In a processing device associated with a display device that has a plurality of pixels, each pixel having a plurality of separately controllable pixel sub-components, a method of selecting filters to provide anti-aliasing in rendering an image, comprising the acts of:

• identifying the font size of a first character to be rendered, wherein the first character has a first font size;
• selecting a first filter based on the font size of the first character to be rendered, wherein the first filter is selected from a plurality of filters based on the amount of anti-aliasing the first filter is adapted to provide and operates by calculating a weighted sum of adjacent samples of image data that represents the first character;
• displaying the first character utilizing the first filter;
• identifying the font size of a second character to be rendered, wherein the second character has a second font size;
• selecting a second filter based on the font size of the second character to be rendered, wherein the second filter is selected from the plurality of filters based on the amount of anti-aliasing the second filter is adapted to provide and operates by calculating a weighted sum of adjacent samples of image data that represents the second character;
• and
• displaying the second character utilizing the second filter.

A computer program product for implementing, in a computer system including a processing device and a display device for displaying an image, the display device having a plurality of pixels, wherein each pixel has a plurality of separately controllable pixel subcomponents, a method of selecting an anti-aliasing filter, the computer program product comprising:

• a computer-readable medium carrying computer executable instructions for performing the method, wherein the method includes the acts of:
• storing a data structure that defines a plurality of different anti-aliasing filters;
• identifying the font size of a character of the image to be rendered;
• selecting, based on the identified font size, an anti-aliasing filter from among the plurality of different anti-aliasing filters, wherein the plurality of different anti-aliasing filters operates by calculating a weighted sum of adjacent samples of image data that represents the image;
• and
• applying the selected anti-aliasing filter in a direction parallel to striping of the pixel sub-components.