Image encoding apparatus and image decoding apparatus both using artificial intelligence, and image encoding method and image decoding method performed by the image encoding apparatus and the image decoding apparatus

An image encoding method using artificial intelligence (AI), the image encoding method comprising:

• obtaining a current optical flow using a current image and a previous reconstructed image;
• generating a current predicted image based on the previous reconstructed image and the current optical flow;
• obtaining correction data by applying the current image and the current predicted image to a neural network-based image encoder;
• and
• generating a bitstream including feature data of the current optical flow and the correction data.

An image decoding apparatus using artificial intelligence (AI), the image decoding apparatus comprising:

• at least one processor configured to:
• obtain, from a bitstream, a current optical flow and correction data which are generated based on a current predicted image and a current image,
• obtain the current predicted image based on a previous reconstructed image and the current optical flow,
• obtain feature data of the current predicted image by applying the current predicted image to a neural network-based predicted image encoder, and
• obtain a current reconstructed image corresponding to the current image by applying the correction data and the feature data of the current predicted image to a neural network-based image decoder.