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DirectShow

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Introduction toDirectShow

playback orcapturevideoandaudiostreams

Support format AdvancedSystem Format (ASF)

Motion Picture Experts Group (MPEG)

Audio-Video Interleaved (AVI) MPEG Audio Layer-3 (MP3)

WAV sound files

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Introduction toDirectShow

automaticallydetects videoandaudioacceleration hardware

Simplifies Mediaplayback, formatconversion,

capture task

Provides access totheunderlyingstreamcontrolarchitecture

youcan createyourown componenttosupport new format

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Introduction toDirectShow

Applications youcan write

DVDplayer, videoediting APs,

AVI toASF converter,MP3players

Digital videocapture

Techniques

Component ObjectModel (COM)

IfyouwanttoextendDirectShow,you

needunderstandCOM

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Supports Formats in

DirectShowFileTypes

Windows MediaAudio (WMA) Windows Media Video

(WMV)*

AdvancedSystems Format

(ASF)*

MPEG

AVI QuickTime (version 2 and

lower)

WAV AIFF

AU (Unix Audio) SND (Sound File)

MIDI

* NeedWindows Media FormatSDK

( WMA WMV)

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Supports Formats in

DirectShow

Compression formats

ISO MPEG-4 video version 1.0* WMA*,WMV*,MP3

MicrosoftMPEG-4 version 3* Sipro Labs ACELP*

DigitalVideo (DV) MPEG-1 (decompressiononly)

MJPEG Cinepak

MPEG2 decoderis not supportbyDirectShow

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DirectShow FAQ

WhatOSdoes DirectShow support?

Win98,Win2000,WinME, WinXP

Do I needtoknowCOMknowledge? Howtoinstantiatethem

Access theinterfacetheyexpose

Managereferencecount

(Filterdesignerrequires more )

Is thereaDirectShowHardwareCompatibility List (HCL) ?

Using DirectDraw & DirectSoundhardware,iftheyavailable

Orusing GDI video & waveOut* audio

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DirectShow FAQ

Whatlanguagecan I use? DirectShowis designed forC++

VB access subsetoftheAPI

ScriptbasedDVDorTVAP

Willitaccessiblethroughmanaged code? nocurrentplans,theCLR is notrecommended

forperformancereasons

Howdoes DirectShowrelatetoMicrosoftActiveMovie?

theoriginal name forDirectShow

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DirectShow FAQ

Information MSDNDirectX DeveloperCenter

http://go.microsoft.com/fwlink/?LinkId=10138 MSDNAudio & Video node

http://go.microsoft.com/fwlink/?LinkId=19380

Maillist http://discuss.microsoft.com/archives/DIRECT

XAV.htm UseNet

microsoft.public.win32.programmer.directx.video

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FAQ

Books

Programming Microsoft

DirectShow forDigitalVideoandTelevision

DirectShow:CoreMediaTechnologyin Windows XP

Empowers YoutoCreateCustomAudio/Video ProcessingComponents

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FAQ

Howdo I buildmyapplication?

Header file Required For

Dshow.h All DirectShow

APs

HeaderFile

Library Files

Library file Description

Strmiids.lib Exports the Class ID (CLSIDs)

Interface ID (IIDs)

Quartz.lib Exports the AMGetErrorTextfunction,, link

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FAQ

DetectwhetherDirectShowis

installed?

IGraphBuilder*pGraph;

HRESULThr=CoCreateInstance (CLSID_FilterGraph,NULL,

CLSCTX_INPROC_SERVER, IID_IGraphBuilder,

(void **) &pGraph);

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Introduction toDirectShow

Application Programming

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Filter& FilterGraphs

Filteris acomponentand

building block

receiveinputandproduceoutput

Filter

DecodeMPEG-1MPEG-1 encoded

stream Frame1Frame2

Frame3

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FilterGraph

APs performs taskbyconnecting

chains of filters together

A setofconnected filters is

calledafilter graph

a filter graph forplaying an AVI file

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Writing aDirectShow

Application Threetasks mustbeperformed

Filter GraphManager

Filter GraphManager

filter graph

Filter GraphManager

filter graph

1 23

When processing is completed,

theapplication releases the FilterGraphManagerandallofthe filters

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Using COM

COM

COMobject

COMinterface

COM lifetime

C COM

Macros DirectX COMMethod

DirectX SDK