This data output device comprises: a video decoding unit that generates a first video signal in a first luminance range by decoding a video stream; an external meta acquisition unit that obtains first metadata relating to the luminance range of the first video signal; an HDR meta interpretation unit that obtains characteristics data indicating the luminance range of the first video signal, by interpreting the first metadata; an HDR control information generation unit that converts the characteristics data into HDR control information conforming to a prescribed transmission protocol; and an HDMI output unit that outputs the HDR control information using the prescribed transmission protocol.