Wireless device

An external device in a wireless display system including the external device and a wireless device, the external device comprising:

• a wireless transceiver;
• a display;
• and
• a processor configured to control the display and the wireless transceiver,
• wherein the processor is configured to:
• display a source video,
• transmit, to the wireless device, a first video signal corresponding to the source video being displayed by the external device so as to cause the wireless device to display a first mirrored video based on the first video signal,
• transmit a first message to the wireless device inquiring whether the wireless device can support a specific picture quality setting for the source video being displayed by the external device,
• wherein the specific picture quality setting is selected from among a plurality of picture quality factors including brightness, contrast, sharpness, HDR, and Dolby Vision,
• in response to the first message, receive, from the wireless device, a second message including a response as to whether the specific picture quality setting is supported by the wireless device,
• wherein the second message includes a picture quality setting function support field having a first field value indicating that the specific picture quality setting is supported by the wireless device and a second field value indicating that the specific picture quality setting is not supported by the wireless device,
• wherein, when the second message includes the second field value indicating that the specific picture quality setting is not supported, the processor configured to receive, from the external device, a second video signal that was not processed with the specific picture quality setting at a picture quality controller of the external device, and to receive a first packet for parameter setting from the external device that does not include values of one or more picture quality factors for the specific picture quality setting, and
• wherein, when the second message includes the first field value indicating that the specific picture quality setting is supported, the processor is configured to receive, from the external device, a third video signal that was processed with the specific picture quality setting at the picture quality controller of the external device, and to receive a second packet for parameter setting from the external device that includes values of the one or more picture quality factors for the specific picture quality setting.