Method and device for changing orientation of image by wfd sink

A method for changing an orientation of an image by a WFD sink may comprise the steps of: transmitting, to a second WFD device, an RTSP M3 request message for requesting information on a video stream control RTSP parameter of the second WFD device by a first WFD device; receiving an RTSP M3 response message in response to the RTSP M3 request message from the second WFD device by the first WFD device, wherein the RTSP M3 response message includes a video stream control RTSP parameter for a video stream control capability of the second WFD device, transmitting a first video stream displayed in a first orientation on the second WFD device to the second WFD device by the first WFD device; receiving an RTSP M21 request message from the second WFD device by the first WFD device, wherein the RTSP M21 request message requests a change into a second video stream displayed in a second orientation on the second WFD device of the first video stream; and transmitting an RTSP M21 response message to the second WFD device by the first WFD device, wherein the RTSP M21 response message indicates the acceptance of the change.