A method for predicting an image is provided. The method include (i) determining prediction parameters of a current block in a bitstream; (ii) determining a matrix-based intra prediction (MIP) input sample of the current block based on neighboring samples of the current block and the prediction parameters; (iii) setting a shifting number parameter (sW) as a first fixed value; (iv) setting a shifting offset parameter (fO) as a second fixed value; and (v) determining an MIP prediction sample of the current block based on an MIP weighting matrix, the MIP input sample, the shifting offset parameter (fO), and the shifting number parameter (sW).