Mar 18, 2016
EnablingEnablingMedia Playback On Media Playback On Windows CE 5.0Windows CE 5.0
Li-Ming FanEscalation EngineerMicrosoft GCR GTSC
Agenda• Multimedia Overview and Architecture• Windows Media Playback Pipeline
– Streaming features on CE 5.0
CE Multimedia Goals• Provide a rich set of multimedia
technologies that enable customers to rapidly build a variety of consumer devices– Small, Fast, Hardware Assisted– Compatibility with desktop Windows
when possible– Optimized support for multiple CPUs and
Systems on Chip
Current MM Technologies• CE v5.0
– Windows Media v9 improvements/new codecs– Direct3D Mobile
• CE v4.2– Windows Media v9
• CE v 4.0 – Windows Media Player Application– Windows Media v8– DVD
• CE v 3.0– DirectShow, DirectDraw– Windows Media Player OCX v6.4
Incr
easi
ng S
tabi
lity
and
Perf
orm
ance
Incr
easi
ng S
tabi
lity
and
Perf
orm
ance
Windows CE Multimedia• Technologies
– Audio– Video– 2D and 3D Graphics– Codecs – Streaming– DVD-Video– Digital Rights
Management
• Products– MSTV– MSNTV– Windows for
Automotive– Portable Media Center– SmartPhone– PocketPC– VOIP Phone– IP Set-Top-Box– PVR– DMR
Technology Breakdown• DirectDraw
– Drawing surfaces, blting, flipping, overlays, alpha blend, video ports
• Direct3D Mobile– 3D polygon rendering– Direct3D Mobile uses
the same API signaturesas Direct3D
– Lightweight, integer based• Waveform Audio
– Playback, capture, mixing, sample rate conversion, gain classes
• DirectShow– Media playback
• DVD-Video– DVD navigation
and playback– DVD Player app
• Windows Media – Audio/video codecs– Streaming/Local File– WM Player OCX– WM Player app
Windows Media Components
• Streaming– HTTP, MMS, local file
• ASX play list parser and handler
• ASF parser and splitter• DRM/decryption
• Software Codecs– WMV 9 Advanced
Profile (new in 5.0)– WMV – WMA– WMA lossless
(new in 5.0)– WMA Pro
(new in 5.0)• DirectShow standard
renderer filters
CE Multimedia Architecture
Network, File system, Graphics, Audio, DVD DriversNetwork, File system, Graphics, Audio, DVD Drivers
Filter GraphFilter Graph
WM Player ActiveX WM Player ActiveX ControlControl
WMP Sample App,WMP Sample App,IE 6IE 6
DirectDraw/GDIDirectDraw/GDI WaveDevWaveDev
Hardware
Network/Network/File SystemFile System
SourceSource CodecsCodecs
DirectShow Filter Graph ManagerDirectShow Filter Graph Manager
DVD-DVD-VideoVideo
D3DMD3DM
RenderersRenderers
DirectShow DirectShow AppApp
D3D Mobile, DVD,D3D Mobile, DVD, DDraw AppsDDraw Apps
WMVWMV
WMAWMAMPEMPE
GG
Encoding For Local Playback
• Variable bit rate is good for conserving disk space
• CE 5.0 supports high content bit rates• Make sure indexing is turned on
– The playback pipeline uses the index to rapidly seek for trick modes
– Trick mode performance is degraded without an index
New Streaming Features• FastStart
– Enables stream to buffer at speeds higher than the bit rate of the requested content
– Buffer fill rate governed by bandwidth of the pipe and limits set on the Windows Media server
– Supported for live broadcast and on demand– Only supported on unicast streams
• Startup profile– Improves stream start time over FastStart– Important for IPTV channel change latency– Only for the HTTP unicast protocol
How Startup Profile Works• Windows CE will look at the content and calculates an
acceleration duration based on the content preroll, bit rate, and the FSAccBandwitdth
• The Windows Media Server (WMS) uses this acceleration duration value as the length of time to scan the content for the startup buffering requirements
• WMS then determines a minimal buffer (essentially a preroll) that the client decoder requires to play the acceleration duration without starving the decoder
Streaming Protocols• Multicast
– Each packet is broadcast to multiple clients
• Microsoft Media Stream (MMS)– TCP connection for commands between client and server– UDP connection for commands between client and server– Automatic protocol roll-over (UDP, TCP)
• HTTP– Will automatically come through corporate firewalls– Will use Internet Explorer’s proxy-settings, or configure its own
settings
• RTSP– Not supported on Windows CE
• File-based (local or network redirector)
Protocol Comparison On CE
• MMS is good for up to 2Mb/s– No fast start and startup profile– Lighter network load (no ack’s)– Requires more reliable hardware and well dimensioned
networks– MMS is getting deprecated in servers in favor of RTSP
and HTTP• HTTP is better at high bit rates – internally tested
up to 10Mb/s on CE 5.0– Fast start and startup profile
Encoding For Streaming• Preroll
– We use 5 seconds for HTTP unicast– MMS as low as 1 second for a quiet network
• No startup profile
– Multicast as low as 1 second for a quiet network• No fast start and startup profile
• Bit rate – Highest for your pipe
• Key frame distance– 5 seconds for HTTP/MMS unicast– 1 second for Multicast (faster startup)
Tools & Resources
msdn.microsoft.com/msdn.microsoft.com/ embeddedembedded
microsoft.public.microsoft.public. windowsxp.embeddedwindowsxp.embedded windowsce.platbuilderwindowsce.platbuilder windowsce.embedded.vcwindowsce.embedded.vc
blogs.msdn.com/blogs.msdn.com/ mikehallmikehall
Windows CE 5.0 Eval KitWindows CE 5.0 Eval KitWindows XP Embedded Eval KitWindows XP Embedded Eval Kit
msdn.microsoft.com/msdn.microsoft.com/ mobilitymobility
microsoft.public.microsoft.public. pocketpc.developer pocketpc.developer smartphone.developer smartphone.developer dotnet.framework.compactframeworkdotnet.framework.compactframework
blogs.msdn.com/blogs.msdn.com/ windowsmobilewindowsmobile vsdteamvsdteam netcfteamnetcfteam
Windows Mobile 5.0 Eval KitWindows Mobile 5.0 Eval Kit
WebsitesWebsites
NewsgroupsNewsgroups
BlogsBlogs
ToolsTools
BuildBuild DevelopDevelop
请在课程结束后填写课程培训反馈表,参加抽奖。请填写资料袋内的蓝色大会满意度反馈表,到大会接待台领取《 Windows Mobile手机应用开发》工具书。您还可以:参加 Windows Mobile 动手实验室;参观微软及合作伙伴展区;体验基于 Windows Mobile 平台开发的最新硬件产品及解决方案。
大会注意事项