An image decoding method and apparatus obtain intra prediction feature data of a current block from a bitstream, determine an intra flow indicating a reference pixel of a current pixel in the current block, by applying the intra prediction feature data, neighboring pixels of the current block, and coding context information of the current block to a neural network, obtain a predicted pixel of the current pixel based on the intra flow of the current block, and reconstruct the current block based on the predicted pixel.