US Patent 11711516 Intra prediction using polynomial model

A method for video processing includes performing a conversion between a current video block and a bitstream representation of the current video block using an intra-prediction coding scheme based on an n-order polynomial model using at least one variable associated with the current video block, where n is an integer greater than or equal to zero, wherein the conversion includes generating the current video block from the bitstream representation or generating the bitstream representation from the current video block.