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Miracast is a program of the Wi-Fi Alliance based on their Wifi-Display specification. It defines a protocol to connect an external monitor or TV to a device, and therefore can roughly be described as "HDMI over Wi-Fi", replacing the cable from the computer to the display.〔(On Wifi-Display, Democratic Republics and Miracles ), Patrick Herrmann, on the development of Miraclecast, 2014-02-17.〕 It is peer-to-peer, and wireless, using a Wi-Fi Direct connection. It allows sending up to 1080p HD video (H.264 codec) and 5.1 surround sound (AAC and AC3 are optional codecs, mandated codec is linear pulse-code modulation — 16 bits 48 kHz 2 channels).〔(【引用サイトリンク】url=http://www.wi-fi.org/knowledge-center/faq/what-formats-does-miracast-support )〕 The connection is created via WPS and therefore is secured with WPA2. IPv4 is used on the internet layer. On the transport layer, TCP or UDP are used. On the application layer, the stream is initiated and controlled via RTSP, RTP for the data transfer.〔("Miracast unter Linux ist schrecklich" ), golem.de, 2014-02-02.〕〔(【引用サイトリンク】title=Wi-Fi Certified Miracast : Extending the Wi-Fi experience to seamless video display )〕 Adapters are available that plug into HDMI or USB ports that enable Non-Miracast devices to connect via Miracast. == Devices == The Wi-Fi Alliance maintains a current (list of Miracast-certified devices ), which features 3,438 devices as of February 2, 2015. Nvidia announced support for it in their Tegra 3 platform, and Freescale Semiconductor, Texas Instruments, Qualcomm, Marvell Technology Group and other chip vendors have also announced their plans to support it. Both devices (the sender and the receiver) need to be Miracast certified for the technology to work. However, to stream music and movies to a non-certified device there will be Miracast adapters available that plug into HDMI or USB ports. On 29 October 2012, Google announced that Android version 4.2+ (from updated version of Jelly Bean) are supporting the Miracast wireless display standard, and by default have it integrated .〔(Android 4.2 adds official support for Miracast wireless display )〕 As of January 8, 2013, the LG Nexus 4 and Sony's Xperia Z, ZL, T and V officially support the function, as does HTC One, Motorola in their Droid Maxx & Ultra flagships, and Samsung in its Galaxy S III and Galaxy Note II under the moniker ''AllShare Cast''. The Galaxy S4 uses Samsung Link for its implementation. In October 2013, BlackBerry released its 10.2.1 update to most of the existing BlackBerry 10 devices available at that time. As of March 2015, the BlackBerry Q10, Q5, Z30, and later models support Miracast streaming; the BlackBerry Z10 does not support Miracast, due to hardware limitations. In April 2013, Rockchip unveiled a Miracast adapter powered by the RK2928.〔(【引用サイトリンク】title=Rockchip Unveils RK3168 Dual Core Processor, Showcases $10 Miracast Adapter )〕 Microsoft also added support for Miracast in Windows 8.1 (announced this in June 2013). This functionality first became available in the Windows 8.1 Preview, and is available on hardware with supported Miracast drivers from hardware (GPU) manufacturers such as those listed above. The WDTV Live Streaming Media Player added Miracast support with firmware version 2.02.32 The Amazon Fire TV Stick, which started shipping on 19 November 2014, also supports Miracast. On 28 July 2013, Google announced the availability of the Chromecast powered by a Marvell DE3005-A1, but despite the similarity in name and Google's early support of Miracast in Android, the Chromecast does not support Miracast. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Miracast」の詳細全文を読む スポンサード リンク
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