Blended error diffusion and adaptive quantization
AssigneeXerox Corporation
InventorsBeilei Xu, Robert Loce
Life of this patent
Estimating the term…
Abstract
A target pixel is processed according to a blended combination of two or more error diffusion techniques. For example, the two or more techniques may include a standard error diffusion technique and rank ordered error diffusion. Additionally, or alternatively, a quantization resolution is selected for the target pixel based on information regarding the pixel. For example, a quantization resolution is selected based on a relative position of the target pixel or based on a value of the target pixel and/or values of pixels neighboring the target pixel.
Claims40
A method for halftoning an image, the method comprising:
- selecting a target pixel from the image;
- quantizing the target pixel;
- determining a quantization error value based on the quantization of the target pixel;
- and
- distributing error to pixels neighboring the target pixel according to a blended combination of at least two error diffusion techniques.
A method for halftoning an image, the method comprising:
- selecting a target pixel from the image;
- selecting a quantization resolution for the target pixel from a plurality of possible quantization resolutions based on a contone value of the target pixel and/or based on contone values of pixels neighboring the target pixel;
- quantizing the pixel value of the target pixel according to the selected quantization resolution;
- and
- halftoning the selected target pixel through an error diffusion process in accord with the quantization.
An imaging system comprising:
- an image processor that is operative to receive an image, select a target pixel from the image, quantize the target pixel, determine a quantization error value based on the quantization of the target pixel and distribute error to pixels neighboring the target pixel according to a blended combination of at least two error diffusion techniques.
Dependencies are inferred from the claim text.