Miracast

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Miracast is a peer-to-peer radio screencast standard that was defined in 2012 by the Wi-Fi Alliance . It is seen as an open standard to Apple's AirPlay , Samsung's Screen Mirroring, and Intel's Wireless Display (WiDi) , although the specifications of the standard are only made available to developers after paying a large amount of money. Among other things, the standard enables the screen content of a smartphone or computer to be transmitted to a large monitor or video projector , for example for presentations . Scenarios such as streaming television programs from a TV receiver to a tablet computer are also possible. Miracast does not need to be integrated into a complete wireless network , since any two devices can be connected to each other using the WiFi Direct standard .

The official Android operating system supports the Miracast standard from version 4.2 Jelly Bean up to version 6.0 Marshmallow . This makes the Google Nexus 4 , which was shipped with Android 4.2, the first Android smartphone with Miracast support. Miracast is embedded in the operating system in a similar way to AirPlay in Apple's iOS . Blackberry OS 10, Microsoft Windows and Windows Phone since version 8.1 also support Miracast.

overview

Miracast allows mobile devices to securely combine videos of up to 1080p ( Full HD ) with 5.1 surround sound ( AAC and AC3 are optional codecs, but support for LPCM with 16 bit at 48 kHz with 2 channels) is required compatible display device.

Compatible operating systems at a glance

equipment

Intel's WiDi drivers have also supported sending to Miracast receivers since version 3.5 (October 2012). In addition to Intel, manufacturers Broadcom , Marvell , MediaTek , Ralink and Realtek also wanted to integrate the standard in their products. The first devices available to end consumers include the Google Nexus 4, LG Optimus G , Samsung's Galaxy S III , Sony Xperia L, T, V, Z, ZL & SP, Blackberrys from OS 10.2.1 and LG Smart TVs Devices 2013 (LA6208-LA8609, LN4607, LN5708, LN5758 and LN5778), Samsung's Echo P-Series TVs (models ES7090 and ES8090), Philips TVs of the year 2013 (Smart TVs 4508-8008) and Sony TVs of the Model series W6, W8, W9 and X9.

Nvidia has announced that Miracast will be supported by the widely used Tegra 3 platform . In addition, other large chip manufacturers such as Texas Instruments , Qualcomm and Marvell have announced plans to integrate Miracast support into their products.

In order to start an image transmission between two devices with Miracast, both devices must be able to use the Miracast standard. If the playback device does not support this standard, a separate Miracast receiver can be used, which is plugged into the HDMI connection of the device. Power is supplied via USB .

In Windows 8.1, Miracast requires appropriate driver support. A WDDM 1.3 driver with Miracast support is required for the graphics side. An NDIS 6.3 driver is required on the network side. The Miracast compatibility of a Windows 8.1 system that is to be used as a transmitter can be tested with the DxDiag diagnostic program.

With the Rollup Update for Windows 8.1 from August 2014, Microsoft implemented API functions that are intended to enable third-party manufacturers to operate Windows 8.1 devices with corresponding software extensions as Miracast receivers.

The AirServer Universal from AppDynamic has been available since November 2014. In the Windows 8.1 version of the software, a Windows 8.1 system that supports Miracast in terms of hardware and is up to date with the current patch status (at least the August Rollup Update for Windows 8.1 is installed) can act as a Miracast receiver.

Windows 10 Mobile devices with Continuum support can connect wirelessly to Miracast-enabled displays or televisions.

restrictions

The industrial standard for Miracast was developed based on the consensus of the interested manufacturers (including Intel, NVIDIA, Google, Microsoft, Texas Instruments and the Wi-Fi Alliance). With Miracast, the entire screen including the sound is transmitted from the Miracast functions of the operating system to the Miracast receiver. The relevant publications are not openly accessible outside the participating group of companies.

The requirement for Miracast is a WLAN module on the transmitter and receiver. Miracast is limited to devices that support the Wi-Fi Direct protocol, adopted by the Wi-Fi Alliance in 2010. Wi-Fi Direct as the basis for Miracast has the advantage that no access to a WLAN network is necessary for use. This particularly facilitates the use for strangers who z. B. only want to send a presentation wirelessly to a projector. With Miracast it is also possible to establish a connection to a WLAN via a router or access point and at the same time activate a Miracast connection.

One problem in practice is the inadequate and incomplete implementation of the protocol scope specified by the manufacturer consortium in the firmware of various Miracast receivers. Furthermore, the Miracast consortium does not have a test suite on which conformity tests can be carried out. In practice, this leads to the unpleasant situation that the coupling of Miracast sources and Miracast receivers becomes a game of chance. An operating system update for Windows 8.1 or Android (from 4.2.2) can lead to an improvement, but also to a deterioration in compatibility.

Alternative radio paths based on the Bluetooth standard have not yet been matched with the Miracast approach, the implementations and the profiles used for this are not compatible. Information about sufficient bandwidths for video transmission is not published. Due to various technical requirements, audio transmissions with Bluetooth cannot be easily compared with Miracast, but they are compatible with one another, even though certification has not yet been published.

Individual evidence

  1. ↑ Sebastian Grüner: Wifi display: "Miracast under Linux is terrible" , Golem.de , February 2, 2014
  2. ^ Zachary Lutz: NVIDIA throws support behind Miracast as wireless display standard
  3. ↑ Kevin C. Tofel: With Miracast, Nvidia's Tegra 3 enables wireless displays , July 26, 2012
  4. ↑ Windows RT Compatibility & Miracast Certification To Enhance TI's Connectivity Solutions , June 15, 2012
  5. ↑ Jon Brodkin: AirPlay for all? Miracast promises video streaming without the router , July 10, 2012
  6. ↑ Nilay Patel: Android 4.2 adds gesture typing, wireless TV display, multiple user support on tablets, and more , October 29, 2012
  7. ↑ Taylor Wimberly: Android 4.2 adds official support for Miracast wireless display , October 29, 2012
  8. ↑ Archived copy ( memento of the original dated December 9, 2013 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.wi-fi.org
  9. ^ Brian Klug: NVIDIA Announces Compatibility with WiFi Display Miracast Specification , July 26, 2012
  10. ↑ Archived copy ( memento of the original from November 25, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.wi-fi.org
  11. ↑ http://forum.samygo.tv/viewtopic.php?f=51&t=4406
  12. ↑ Nvidia supports Miracast . Retrieved October 13, 2013.
  13. ↑ Airplay for all? . Retrieved October 13, 2013.
  14. ↑ a b Klaus Länger: HDMI without cable: Miracast & Co , Computerwoche, August 9, 2015
  15. ↑ Miracast on Windows 8.1 - Part 3
  16. ↑ August 2014 update rollup for Windows RT 8.1, Windows 8.1 and Windows Server 2012 R2 .
  17. ↑ AirPlay Miracast receiver for PC
  18. ↑ Windows 8.1 as a Miracast receiver - Part 1
  19. ↑ Archived copy ( Memento of the original from July 14, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / intel.activeevents.com
  20. ↑ [1]
  21. ↑ [2]
  22. ↑ Archived copy ( Memento of the original from July 15, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / ces.karlsruhe.de
  23. ↑ [3]
  24. ↑ [4]
  25. ↑ Hands on: Streamcasting with DLNA, Miracast, Airplay & Co.
  26. ↑ [5]
  27. ↑ [6]
  28. ↑ [7]
  29. ↑ [8]