Multimedia development For Windows CE.NET

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Multimedia development For Windows CE.NET
Authored and Presented By Asaf Shelly Digital
Media MVP
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Agenda

• Introduction
• Windows Media Technologies overview
• Windows Media Technologies details
• Windows Media Technologies architecture
• Media types
• Scenarios

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Introduction

• Microsoft MVP who we are.
• Windows CE real time OS.
• DirectX Direct access to hardware.
• Codecs.
• Multimedia.

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Media Technologies overview

• Source storage, stream.
• Format Raw, Compressed.
• Quality vs. Bandwidth.
• For audio sound, voice.
• For video encoder features.
• Loosing data.

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Media Technologies details

• Waveform Audio
• Windows Media Contents Formats
• DirectX media technologies
• DirectShow
• Direct3D
• DirectSound
• DirectMusic
• DirectDVD

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Waveform Audio

• Is used to add sound to an application
• PlaySound function adds routine sound
  capabilities to a device
• BOOL sndPlaySound( LPCTSTR lpszSoundName, UINT
  fuSound )
• PlaySound function allows to play waveform audio
  sound files, as long as the sound can be stored
  in available device memory
• Provides three ways to play a sound
• As a file name
• As a system alert, using the alias that is stored
  in the registry
• As a resource identifier

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Waveform Audio

• In Windows CE, most waveform audio files use the
  .wav file name extension
• Example showing how to play the \Sounds\Bells.wav
  file
• PlaySound(TEXT("\\SOUNDS\\BELLS.WAV"), NULL,
  SND_SYNC)
• If the specified file does not exist or the file
  cannot be stored in available device memory
• PlaySound function plays the default system
  sound
• Example showing how to specify that the default
  sound should not be played
• PlaySound(TEXT("\\SOUNDS\\BELLS.WAV"), NULL,
• SND_SYNC SND_NODEFAULT)

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Waveform Audio

• Waveform Audio API
• Provides the greatest control over audio I/O
  devices
• Uses waveOutOpen and waveInOpen functions to
  determine the support for the specified format
• The Waveform Audio API enables the following
  capabilities
• Querying and opening waveform audio I/O devices
• Allocating audio data blocks
• Playing waveform audio files
• Handling errors generated by audio functions
• Using windows messages to manage waveform audio
  playback
• Deallocating memory blocks associated with audio
  data
• Closing waveform audio output devices

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Windows Media Contents Formats
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Windows Media Player

• ActiveX Control Used by Developers to Implement
  Multimedia
• Sample application provided with Platform Builder
• Visual C programming or COM not needed to use
  it
• Implemented through DS Filter Graph
• The WMP control can receive streamed content in
  one of two ways
• By connecting directly to the media server to
  receive clips.
• By monitoring a defined IP address and port for
  multicast streams
• ASX files
• Based on XML syntax
• Syntax and order are key to successful
  implementation

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Windows Media Technologies architecture
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DirectX

• What is DirectX
• A set of APIs that enables programmers to write
  programs that access hardware features of a
  computer without knowing exactly what hardware
  will be installed on the machine where the
  program eventually runs
• DirectX achieves this by creating an intermediate
  layer that translates generic hardware commands
  into specific commands for particular pieces of
  hardware
• Hardware Abstraction Layer and Hardware Emulation
  Layer
• HAL is a device-specific interface, which
  DirectDraw uses to work directly with the display
  hardware
• HAL can be part of the display driver or a
  separate DLL
• HEL provides the emulating functionality for
  features that are not supported through HAL

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DirectDraw

• DirectDraw API provides fast access to display
  hardware while retaining compatibility with GDI
• Features of DirectDraw
• Bit-block transfers (blits)
• Page flipping and multiple back buffers
• Overlays
• Alpha source over destination blending
• Video YUV pixel formats and color conversion
• Direct video access to the frame buffer

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DirectShow

• The Multimedia Challenges include
• Synchronizing multiple streams (audio/video) in
  various formats from various sources
• The DirectShow Solution
• Simplifies the task of creating multimedia
  applications on the Windows platform
• Uses DirectDraw and DirectSound to render data
  efficiently
• Provides modular filter architecture
• Filters fall into three categories
• Source Filters
• Transform Filters
• Renderer Filters

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Direct3D

• Provides basic support for interactive 3-D
  graphics applications
• Is a low-level 3-D API
• Is a software interface that provides direct
  access to display devices while maintaining
  compatibility with GDI

• Is useful for applications, such as CAD, games
• Is a subset of 3-D interfaces in DirectX 8 for
  Windows
• Windows CE does not support some of the Direct3D
  8 features supported by desktop

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DirectSound

• Is a wave-audio component of DirectX API
• Why use DirectSound?
• Querying hardware capabilities at run-time
• Using property sets
• Low-latency mixing of audio streams
• Capturing sound
• DirectSound architecture
• Allows the use of hardware in the most efficient
  way
• Provides higher performance than Waveform audio
• COM interfaces
• DirectSound playback is built on the IDirectSound
  COM interface

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DirectMusic

• Is a musical component of the DirectX API
• Works with message-based musical data, which is
  then converted to digital wave samples
• Supports MIDI and run time compositions
• Uses DirectMusic Producer as an authoring tool
• Core layer manages timings and ports
• Performance layer is responsible for higher-level
  aspects of music playback
• Obtains data from MIDI, segment, or component
  files

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DirectDVD

• Is an extensible COM-based based middleware
  framework
• DVD-Video API
• Enables rich DVD playback capabilities
• Designed to operate in small memory footprint
• Is optimized for hardware-based decoding
  solutions
• Does not support Karaoke, VCD, SVCD
• Architectural overview goals
• DirectDVD implementation provides access to all
  information found on the DVD-Video disc through
  the DirectDVD interfaces
• Not restrict OEM features that go beyond the
  standard DVD functionality

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Scenarios

• Digital Media Receiver
• DVD-Video device
• Mobile phone
• IP Phone
• Digital camera
• Set-top box
• MP3 player
• Web pad

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Digital Media Receiver

• Digital Media Receiver provides a starting point
  for creating a range of devices for delivering
  audio and video content
• The features available in DMR are focused on
  devices that will be integrated into home
  entertainment centers
• A DMR based device may require dedicated hardware
  for audio and video rendering or for media
  decoding
• The dependency on multimedia hardware, leaves
  most feature combinations for the DMR not
  workable on the Emulator
• Those that do work have lower quality multimedia
  performance

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Digital Media Receiver Demo
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Media File Formats

• Video formats compressed and raw.
• Audio formats compressed and raw.
• Reducing weight.
• Loosing weight.
• MPEG4, motion.
• CBR, VBR.
• ASF.

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Streaming

• Local storage.
• LAN.
• WAN.
• Wireless.
• Multicast vs. Unicast.
• MMS. Multiple bitrates.

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Windows Media Player

• ActiveX control, automation.
• DirectX wrapper.
• DirectShow abstraction.
• XML Parsing ASX.
• .Net
• Flexible input.

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Windows Media Loop

• Media player client.
• ASX Scripting / Automation.
• MMS Server, RTSP, HTTP.
• Playlists.
• Encoder.
• MM2.

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Performance Using Media Player

• Buffering.
• Clock Drift.
• Caching.
• RTSP, HTTP.
• Storage vs. network, CBR vs. VBR.
• COM.
• Push ahead.

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Other Resources

• http//msdn.microsoft.com/
• http//www.microsoft.com/windowsmedia/
• http//www.microsoft.com/windowsce/
• Contact Me at ContactMe_at_Shelly.co.il