摘要 |
Images can be coded based on filters defined by filter coefficients or weights assigned to previously decoded pixel values of nearby lines. The filter coefficients can be selected based on evaluation of a set of predetermined filters, or filters can be adaptively generated and then evaluated. The filters generally are based on pixel values in previous rows or columns, but not values in the current row or column. In some examples, filters are adaptively generated pixel by pixel, or portions of previous rows, columns, or previously decoded portions of the current row or columns are used to provide line templates. A filter is generally selected to reduce coding error based on a least square difference between the current value and a prediction.
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