1. An image coding method for coding an current block included in an image, the image coding method comprising: selecting a first prediction direction from a first prediction direction set that is part of a plurality of previously determined prediction directions, and includes one or more of the prediction directions; and performing intra prediction on the current block by using a pixel of an adjacent block that is adjacent to the current block based on the selected first prediction direction, wherein the first prediction direction is selected from one or more prediction directions included in the first prediction direction set, based on a prediction pixel generated by copying the pixel of the adjacent block, the prediction pixel being generated without filtering.