Ok soooo full circle Explain Miracast ... I was sooo hoping to avoid going down that rabbit hole.
2012.
http://blog.clove.co.uk/2012/11/16/wifi-miracast-what-does-it-do/
2013
http://www.howtogeek.com/177145/wir...ed-airplay-miracast-widi-chromecast-and-dlna/
Wifi.org
http://www.wi-fi.org/discover-wi-fi/wi-fi-certified-miracast. perhaps biased
From Wikipedia
Miracast is a certification program of the
Wi-Fi Alliance based on their Wifi-Display specification. It defines a protocol to connect an external monitor or TV to your device, and therefore can roughly be described as "
HDMI over
Wifi", replacing the cable from the computer to the display.
[1]
It is
peer-to-peer, and wireless, using a
Wi-Fi Direct connection. It allows sending up to
1080p HD video and
5.1 surround sound (
AAC and
AC3 are optional codecs, mandated codec is
linear pulse-code modulation — 16 bits 48 kHz 2 channels).
Advantages
The technology was promoted to work across devices, regardless of brand. Miracast devices negotiate settings for each connection, which simplifies the process for the users. In particular, it obviates having to worry about format or
codec details.
[16] Miracast is "effectively a wireless
HDMI cable, copying everything from one screen to another using the H.264 codec and its own
digital rights management (DRM) layer emulating the HDMI system".
Disadvantages
Miracast is limited to
Wi-Fi Direct supported devices. Comparing to other IP-based screen mirroring applications such as Splashtop,
[18] MirrorOp,
[19] VNC and
RDP, Miracast cannot run on all IP networks such as conventional Wi-Fi,
wired Ethernet,
HomePlug powerline networking and Internet, but those IP-based screen mirroring applications can run on Wi-Fi Direct. The Miracast standard also has "optional components" such as
Wireless Multimedia Extensions (WMM). The use of optional components in "standards" often causes issues if one vendor supports the options components and another does not. Its reliance on Wi-Fi Direct also reduces the attractiveness of the technology in enterprise environments.
The development of the support in Linux took 4 months, and the relevant developer originally recommended not to buy or use devices supporting Miracast. The following reasons were cited:
[1][2]
- the specification is only available on payment of a high amount of money.
- hardware support is barely available, the only working chip in February 2014 was Intel's 7260-WLAN-Chip.
- he considers the technology "horrible". Filters are sent which define properties of the hardware, e.g. the screen resolution. This boils down to an enormous amount of data sent which makes its challenging to find the correct peering device. IPv4 including DHCP is used as internet protocol, not the new IPv6. To transfer contents the sender and receiver device should be done, but sometimes this happens spontaneously without a possibility to change it afterwards. The streaming is controlled via the RTSP. The disadvantage is that the receiver explicitely needs to request the data transfer from the sender - instead of the sender just starting the transfer.
Latency
Certification does not mandate a maximum latency (i.e. the time between display of picture on the source and display of the mirrored image on the sync display).
Device incompatibility
There are serious incompatibilities between Miracast devices, i.e. being Miracast compatible does not mean devices can talk to each other. On the internet huge lists are collected with devices compatible to each other.
[20][21][22]
HTH.