An encoding device includes a memory, and a processor coupled to the memory and the processor configured to extract a first line-drawing region from a first image in a plurality of images, by replacing the first line-drawing region of the first image with an image which is included in a second image preceding the first image in the plurality of images and corresponds to the first line-drawing region, generate a third image, generate video encoding information by performing a video encoding processing based on the third image, generate line-drawing encoding information by performing a line-drawing encoding processing based on the first line-drawing region, and transmit the video encoding information and the line-drawing encoding information to a decoding device.