A relay apparatus for transferring image data transmitted from a transmission source to a transmission destination, including circuitry to: receive video image data from a first apparatus being the transmission source; determine whether a second apparatus being a transmission destination is capable of reproducing the video image data received from the first apparatus; based on a determination that the second apparatus is not capable of reproducing the video image data received from the first apparatus, apply image processing to the video image data to generate image data compatible with the second apparatus; and transfer the image data compatible with the second apparatus, to the second apparatus.