General Information:

CAviSurface implements an interface to play a true- or highcolor AVI file into a DirectDrawSurface. CAviSurfaceWithSound extends this to play the sound simultaniously into a streaming DirectSoundBuffer.

To use the classes you have to use DirectDraw in a 16-Bit or 24-Bit colormodus. 8-Bit Colordepth is currently not supported, neighter as sourceformat nor as targetformat. This is partially due to the usally installed AVI - Decompressors and partially due to my own laziness.

To use the class you simply have to use the following codefrags:

1. Construct the DirectDraw (and DirectSound) Interface.
2. Call the constructor lpAviSurface = new CAviSurface (or CAviSurfaceWithSound)
3. To start the playback, call lpAviSurface->Start(); // Sound begins to play when using CAviSurfaceWithSound
4. In your general UpdateFrame-Method of the Application call lpAviSurface->BltTo(where.x,where.y,lpddsTargetSurface);
5. Call lpAviSurface->Stop() to suspend playback, another call to lpAviSurface->Start() will contiue the playback.
6. Destroy the Object with delete lpAviSurface;

The class interface

CAviSurface(char *lpszFilename,LPDIRECTDRAW lpDDraw,BOOL bLoop=FALSE)

• Constructs a DirectDrawSurface, linked with an AVI-File

HRESULT SetColorKey(DWORD dwColorKey)

• Set a Keycolor (no Keyspace)

HRESULT BlitTo(int x,int y,LPDIRECTDRAWSURFACE lpddsTarget)

• Draws Videosurface to (left,upper) = (x,y) in Targetsurface

HRESULT StretchBlitTo(RECT *rcTarget,LPDIRECTDRAWSURFACE lpddsTarget)

• Draws Videosurface to Targetrectangle in TargetSuface

virtual BOOL Start()

• Starts Videoplayback into surface

virtual BOOL Stop()

• Stops the playback

CAviSurfaceWithSound(char *lpszFilename,LPDIRECTDRAW lpDDraw,LPDIRECTSOUND lpDS,BOOL bLoop)

• Opens the AVI-File lpszFilename and attaches it to a Directdrawsurface and a DirectSoundbuffer.

• bLoop specifys, if the AVI-File is played looping.

~CAviSurfaceWithSound()

• Frees all the stuff

virtual BOOL Start()

• Starts the soundplay and the videoplayback

virtual BOOL Stop()

• Stops the soundplay and the videoplayback

For more information see the headerfile "avisurfave.h"

download avisurface.zip (64k)

Files in the archive:

• avisurface.cpp, avisurface.h - Implementation of the classes
• dderrmsg.cpp, dderrmsg.h - translates a DDraw errormessage into a text string
• standartmacros.h - exactly one macro (grin)
• videoexample.* MSDEV Projectfiles for the examplecode
• aboutbox.cpp, aboutbox.h - guess what it is
• ddframw.cpp, ddframw.h - the applications main window
• resources.h - the resource defines
• videoexample.exe - release build
• AVISurface.html - this file

The sources compile fine under VC++ 4.2, but it should be easy to convert to other compilers. - (Sometimes I will switch back to Borland)

Remember to run the program in an 16 or 24 bit colordepth environment, because it works in a window, and only supports the high/truecolor target.

To Do:

• I currently do not know how to interpret the value AVIStreamInfo.dwInitialFrames exactly, so there is a problem in the syncronization of the sound and the graphics in some AVI's.
• Adding support for 8-Bit and 32-Bit Colordepth. (I currently do not need this, so no time to do it)

LEGAL ISSUES

I don't promise that this software works and in no case I will be liable to any damage, this software does. (But if you find any bugs, please let me know!) You can use this software for whatever you want. You don't have to pay me. If you use it in a program, please credit me, send a postcard (or a copy of the program).

Gert Wollny
Henricistr. 29
04177 Leipzig
Germany