Method for determining prediction value and decoder

Abstract

Methods for determining a prediction value, an encoder and a decoder are provided. A bitstream is parsed to obtain a size and a coding mode of a current block. Reconstructed values of neighboring samples are acquired and the reconstructed values of the neighboring samples are filtered. A second constant value is calculated according to a bit depth value of a luma component of a sample in the current block. A difference between the second constant value and a first reference value in the reference value set is assigned as a first prediction input value in a prediction input value set. Other prediction input values in the prediction input value set other than the first prediction input value are determined. Prediction values of samples at specific positions in the current block are calculated. The prediction values are filtered to obtain prediction values of all samples in the current block.