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Screencasting
Rex Tsai
[email protected]
http://nutsfactory.net/
H4 @ MR Brown
2013-08-29
(2013-09-01 updated)
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Screen mirroring solutions
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AirPlay
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mirroring standard for iOS.
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Miracast/WiDi
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RTP/RTSP
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Chromecast
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DIAL
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WebRTC
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Apple AirPlay
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Wireless Media Streaming / Screen Mirroring Protocol
for iOS
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Discovery – Bonjour / zeroconf
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AirPlay service / RAOP (Remote Audio Output Protocol)
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FairPlay for protect screen content and encrypted
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UDP-based, based on RTSP
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Codec - Apple Lossless codec with 44100 Hz and 2 channels
and H264
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Proprietary protocol, only license audio-streaming to 3rd
partyies
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Requirement for hacks
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Understand FairPlay / DRM for screen
protection
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FairPlay DRM initiation - ‘/fp-setup’
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Video steaming encryption
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AirTunes/AirPlay private/public RSA keys
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Implement the AirPlay receiver server
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Commerical products of
AirPlay mirroring
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James Laird reverse-engineered and released the
private key
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VMLite rPlay for Raspberry Pi and Windows
– http://www.youtube.com/watch?v=aviPOINM6Bk
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Electroniccolor -
http://v.youku.com/v_show/id_XNTgwMjQzMTk2.html
AirParrot - http://www.airsquirrels.com/airparrot/
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AirServer - http://www.airserver.com/
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Hacksugar: Live AirPlay mirroring to Mac from iOS |
TUAW - The Unofficial Apple Weblog
– http://www.tuaw.com/2012/02/08/hacksugar-live-airplay-mirroring-to-mac/
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Micrast/Wireless Display
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Discovery - WiFi Direct (Layer 2 protocol)
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Media Protocol
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RTP
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RTSP
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Available
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Android 4.2
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Windows client available from Intel
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Built-in in Windows 8.1
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Wi-Fi Display Technical Specification 199USD
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AOSP Miracast Sink
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Android 4.2
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https://github.com/kensuke/How-to-Miracast-on-AOSP/wiki
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https://github.com/kensuke/
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Demo - http://www.youtube.com/watch?v=KNEmaIr3FEg
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Possible to port this feature to Android dongle like mk802
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Chromecast
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DIscovery And Launch http://www.dial-multiscreen.org/
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Based on UpnP & REST
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WebRTC http://www.webrtc.org/
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Support applications
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YouTube
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Netflix
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Google Play Music
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Google Play Movies & TV
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“Google Cast” Browser plugin available for Windows, Mac OS,
Linux.
https://chrome.google.com/webstore/detail/google-cast/boadgeojelhgndaghljhdicfkmllpafd
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Bootloader is hacked
http://wiki.gtvhacker.com/index.php/Google_Chromecast#Bootloader_Exploit_Package
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Does not work in AP Isolation mode
https://support.google.com/chromecast/answer/3213084?hl=en
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Supported Media Types
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Video codecs: H.264 High Profile Level
4.1, 4.2 and 5, VP8
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Audio decoding: HE-AAC, LC-AAC,
CELT/OPUS, MP3
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Containers: MP4/CENC, WebM,
MPEG-DASH, SmoothStreaming
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Level 1 DRM support: Widevine,
Playready
https://developers.google.com/cast/supported_media_types
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Chromecast clone Software
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SINK (Server)
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CheapCast - https://github.com/mauimauer/cheapcast
– Supported Applications
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ChromeCast
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YouTube
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PlayMovies
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GoogleMusic
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GoogleCastSampleApp
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GoogleCastPlayer
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Fling
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TicTacToe
– Unstable, Android's WebView does not work well on old device like mk802.
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SOURCE (Clients)
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AirCast
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RemoteCast
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References
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Unofficial AirPlay Protocol Specification
http://nto.github.io/AirPlay.html
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Wi-Fi Display Technical Specification v1.0.0
http://www.wi-fi.org/knowledge-center/published-specifications
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Stream Laptop Content over HDTV with Intel® Wireless Display
https://www-ssl.intel.com/content/www/us/en/architecture-and-technology/intel-wireless-display.html
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https://www.wi-fi.org/sites/default/files/uploads/wp_Miracast_Industry_20120919.pdf
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DIAL-2ndScreenProtocol-1.6.4.pdf http://www.dial-multiscreen.org/dial-protocol-specification
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Google Cast API https://developers.google.com/cast/