Adaptive area of influence filter for irregular spatial sub-sampled images

摘要

A sample cell corresponding to a sample is computed to include pixels of an image according to sample cell criteria and shape. The sample cell shape and criteria define pixels to include in the sample cell. A target pixel cell corresponding to a target pixel includes pixels of the image according to a target pixel cell criteria defining which pixels are included in the target pixel cell. A sample filter coefficient is computed from pixels in the sample and target pixel cells. A filter tap corresponding to the target pixel is defined based on the sample filter coefficient. A tap extension corresponding to the target pixel is generated. The tap extension defines additional pixels of the image to be included in an extended target pixel cell according to a tap extension criteria. The extended target pixel cell includes pixel in the target pixel cell and the additional pixels. A tap extension filter coefficient based on pixels located in the extended target pixel cell and the sample cell is computed. Sample cell shape is varied according to sample cell shape parameters. An optimal filter weight for the target pixel is extracted from the sample filter and tap extension filter coefficients.