Windows Media SDK 7:
Under the Hood
7-409
Chris Carper
Program Manager
Digital Media Division
ccarper@microsoft.com
Agenda


Windows Media SDK Roadmap
Windows Media Format SDK





Audio, video
Net streaming
Editing
Content management
Digital Rights Management
Window Media v7 SDK
Component Roadmap



Encoder SDK (Private Beta)
Player SDK (Beta)
Format SDK (Beta)



Replaces Audio SDK
Reading and writing Windows Media
Windows Media Device Manager (WMDM)
Windows Media Format 7:
Overview
Requirements

Extensible


Scalable




Support new CODECs and media types
Efficient local playback
Support existing HTTP servers
Enable high capacity media servers
Author once; playback anywhere


Stream thru 28.8 modems to broadband networks
Play on PCs, PDA, and Consumer Electronics

Car stereos, portable devices, etc.
Windows Media Format 7:
Overview




Second generation multimedia format
Supports streamed and local playback
Optimized for live and
on-demand content
Consists of



CODECs
Digital Rights Management (DRM)
File container
Windows Media Applications


Based on current WM
Audio SDK
Players



Winamp (www.winamp.com)
Sonique (www.sonique.com)
Personal Jukeboxes




Sonic Foundry Siren
www.sonicfoundry.com
MusicMatch Jukebox
www.musicmatch.com
RioPort Audio Manager
www.rioport.com
Many more available at…
http://www.microsoft.com/
windowsmedia/software/
jukeboxes/
Windows Media Player v7
SDK



Windows Media Player ActiveX
Control
Windows Media Player Skins
Windows Media Player Custom
Visualizations
Player SDK Component
Architecture
Browsers/applications
Netscape
Plug-in
Player
Control
COM
Interfaces
DirectShow Filter Graph Manager
Source filter
(ASF, WAV, AVI,
etc.)
Transform
filter
Render
filter
DirectX Foundation
Media Source
(Internet or
FileSys)
Media Destination
(Audio/Video Hardware)
Player SDK Component
Control Interfaces

Methods





Player State: Play, Pause,
Stop, FastForward
CODECs: GetCodecInstalled
ASX: GetMediaInfoStream
Stream control: StreamSelect
Events






Script Commands and URLs
Stream and playback
Mouse and keyboard
Marker
Errors and warnings
Timer

Properties











Display and appearance
Markers and scanning
Stream playback rate
Media stream
FilterGraph
Event registration
Error handling
Volume and Mute
Stream and playback
stats
Stream status
SAMI file, language, style
Player SDK component
Windows Media Vizualizations
Getting Started

Use C++ Wizard

Located in <SDK Install>\wizards\viz
Copy to: \Program Files\Microsoft Visual
Studio\Common\MSDev98\Bin\IDE




Create Vizualization Project
Modify Render function
Build .dll
Windows Media Vizualizations
Files
















effects.idl
project.cpp
projectdll.cpp
projectdll.def
projectdll.rc
iproject.idl
StdAfx.cpp
project.h
resource.h
StdAfx.h
project.rgs
project.wms
basetsd.h
effects.h
iproject.h
iproject.tlb
WM Format SDK Features
Audio and Video





Read and write Windows Media files
Stream from net, stream to net
Content Management properties
Markers
Scripts: Closed Captioning, URL flips,
Events, HTML



In stream or in header
Digital Rights Management (DRM)
Portable Device Support
Windows Media Format SDK
Data Flow
Encoder
Player
audio/video data
WM SDK
WM Stream
WM SDK
WM File
DRM
CODEC
DRM
CODEC
Windows Media Format
SDK Objects
WM Format SDK
Writer
IWMWriter
Reader
IWMReader
Metadata Editor
IWMEditor
Profile Manager
IWMProfileManager
File Sink
IWMWriterFileSink
Network Sink
IWMWriterNetworkSink
Format Overview
File Container



Supports files as large as 17 million terabytes
Supports multi-bitrate-video streams in a file
Stores media and metadata in one file

Metadata



Title, copyright, author, markers, script commands, etc.
ID3 v1, v2 music meta-information
Media

Audio, Video and Script Commands (URLs, CC)
AudioStream
Video Stream #1
Header
Index
Video Stream #n
Script Stream
Timeline
Format Overview
File Container





Able to select a stream, based on available bandwidth
Interleaved data is optimal for HTTP
Files can be read sequentially, avoiding expensive seeks
Timeline based synchronization
Bursty data can be smoothed


Send Timestamp
(milliseconds)
Presentation Timestamp
(Rational time units)
Presentation
Time
Send
Time
Presentation
Time
Format Overview
File Extensions

Objectives



ISVs know the player’s rendering requirements
Content owners can target specialized player
(e.g. Jukebox vs Digital VCR)
.wma





Audio-only content
Target application: Jukebox
Metafile extensions: .wax
MIME: audio/x-ms-wma and -wax
CODECs: Windows Media Audio
Format Overview
File Extensions

.wmv






Audio, Video, and/or Scripted content
Target Application: Video Player, Video Editor
Metafile extensions: .wvx
MIME: video/x-ms-wmv and -wvx
CODECs: Uncompressed, Windows Media Audio, ACLEP.net
and/or MPEG4
.asf





Legacy content
Unbounded rendering requirements
Metafile extensions: .asx
MIME: video/x-ms-asf
CODECs: Uncompressed, Windows Media Audio, ACLEP.net,
MPEG4, MetaSound, MetaVoice, MP3, TrueMotionRT,
ClearVideo, L&H, VDOWave, etc.
Format SDK Component
Upgrading from the Audio SDK

Jukebox applications



Faster than real-time read
Transfer content to portable devices
or storage media with WMDM
Live encoder applications



Write-to-net via HTTP and MSBD
Support up to 50 direct connections
Reports encoding statistics
Format SDK Component
Upgrading from the Audio SDK

Video editing applications






Access to compressed and
uncompressed bit-streams
Author single and multi-bit-rate video files
Author and edit script stream, scripts in
header, markers in header, header
attribute editing
Auto-create index for seeking support
Broader list of supported CODECs (MPEG4,
Windows Media Audio, ACELP.net)
Author files larger than 2 gigabytes
Format SDK Component
Keying


WMKey.LIB unlocks all SDK interfaces
Vendor-specific keys in lib file





CODEC keys are also in lib file



ISV registers to download SDK
Server generates an individualized lib file
Server emails lib to ISV
ISV link lib file into app
Allows for CODEC specific keying
Allows for new CODECs without changing the SDK
Key are passed down through middleware APIs
(e.g. DirectShow)
Profile




Multi-bitrate video bands: declare frame
size and bitrate for each band
Persisted as XML
SDK includes pre-defined system
profiles in “windows\wmsysprf.Prx”
Take a look at profile settings…
Writing WM File



Create an IWMWriter object by calling
WMCreateWriter
Call SetProfile to define the
configuration.
Set the outputs.




Call SetOutputFilename on the writer.
Call GetInputCount and GetInputProps for
each stream. Call WriteSample repeatedly,
until finished.
Use AllocateSample
Call Flush

Will write any buffered data as output, and
update the header and index files.
Writing Windows Media Files
Application
IWMProfile
AddStream
IWMWriter
SetOutputFileName
WriteSample
IWMWriterNetwork
SinkOpen
WM SDK
Profile
Object
Writer
Object
Net Sink
Reading a WM File


Create an IWMReader object
Call Open with a URL (possibly a local
file name)





Asynchronous call
Wait for appropriate OnStatus calls to be sent to the
callback
Returns the WMT_OPENED status message to the
callback
Call GetOutputCount and
GetOutputProps to get the format for
each output
Call Start

Status messages and samples will then begin arriving
in the callback function
Reading Windows
Media Files
Application
IWMReader
Open(szURL)
Start(cnsStart)
IWMReaderCallback
OnSample
OnStatus
WM SDK
Reader Object
WM SDK
Editing Windows Media Files




Windows Media Format SDK allows
editing without recompression
Can obtain compressed data
from reader
Can supply compressed data to writer
Compressed samples are handled
separately from normal samples, on
advanced interfaces

IWMWriterAdvanced
Windows Media Rights Manager
Digital Rights Management (DRM)

Allows copyright owners to encrypt content





Users must acquire “license” to play
Content cannot be easily emailed, transferred, or
copied with associated license
Enables artists, publishers and distributors to
collect information and/or money
Designed to vastly reduce digital music piracy
Incorporated in Windows Media Player (WMP)


Also available in Window Media SDK
Incorporated in many third-party players
Rights Manager Process Flow
Building a streaming media business
Windows
Media
Server
Digital
Content
1
Packager
Tool
2
Packaged
Content
3
Web
Server
Creation
Distribution
4
Windows
Media
Player
5
License
Server
Clearing
7
6
License
(Key)
Playback
Content (plaintext)
Content Server
1.
Encrypts content
2.
Allows download
Speaker/Display
2
Content (encrypted)
Consumer PC
3
Shared secret
WMPlayer
1
Authentication
7
License Server
1.
Authenticates client
2.
Encrypts content key
3.
Adds usage rules
4.
Signs license
License request
4
License (key)
5
Parameter
encryption
DRM
6
License
store
Hardware
binding
License Rights




Right to play on a PC
Expiration date
Right to burn to redbook CD
Right to transfer to portable player

One-time right to transfer to PD
Playing Protected Content





Sign license, return to Microsoft
Receive wmdrmstub.Lib
#define SUPPORT_DRM
Call WmCreateDrmReader
Handle WMT_NO_RIGHTS message
Playing Protected Content
(Diagram)
Player
WmDrmStub.lib
music.wma
music.lic
WM SDK
DRM
CODEC
Portable
Device
Service
Provider
Windows Media SDK
Licensing Overview


Components of the OS, so there is no additional
license fee
Tools SDK



Player SDK



Paper-copy redistribution license
Redist component: wmtools.exe (4 Meg)
Automated IEAK redistribution license process
Redist component: mpfull.exe (4 Meg)
Format SDK



Automated license process for core functionality
Paper-copy license for DRM functionality
Redist components:



WMFAudioRedist.exe for Jukebox apps (0.8 Meg)
setupWMDM.exe for Jukebox apps (0.2 Meg)
WMFRedist.exe for video editor or encoder apps (1 Meg)
Logo Program
Plays Windows Media™

Use this logo if your product:


Integrates Windows Media technology to
reads (from net or local disk) Windows
Media files or renders Windows Mediabased content
To request the logo license agreement,
email us at:
wmlogo@microsoft.com
Windows Media
Enabled Solutions
Call To Action

Enable your existing product with
Windows Media


Create new categories of applications


Audio/Video Players, Video
editors, Games
Digital VCR, Conferencing Gateways,
Personal Broadcaster, Media Indexers
Join our Partner Programs
Need More Information?

MSDN Developer Center
http://msdn.microsoft.com/windowsmedia


JumpStartCD
Ongoing Seminars