1. An image decoding method comprising: obtaining information about a color representation from a bitstream; entropy decoding a residue which corresponds to a difference between a current image and a predicted image of the current image; and reconstructing the current image by using the entropy decoded residue and the predicted image, based on the information about the color representation, wherein the reconstructing of the current image comprises: obtaining a prediction direction of a chroma component from among a plurality of prediction modes associated with a prediction direction of a luma component, wherein the plurality of prediction modes include a first mode in which the prediction direction of the chroma component is identical to the prediction direction of the luma component and a second mode in which the prediction direction of the chroma component is different from the prediction direction of the luma component; and obtaining the predicted image based on the prediction direction of the luma component and the prediction direction of the chroma component.