| 
OpenAL
 » 
OpenAL - User

Adding filters

View: New views
2 Messages — Rating Filter:   Alert me  

Adding filters

by Robert Smyth :: Rate this Message:

Reply to Author | View Threaded | Show Only this Message

Hi,
 
I am trying to add filters to a raw source using openal. THe code I am using can be seen below. I have read the sdk ext manual and seem to be doing everything correctly. The program compiles and I get a correct sound device to be found and no erros when creating my filter but instead of playing the filtered source it just repeats what has already been played, i.e the filter doesnt seem to work. I am using microsoft visual studio 9.0 on a dell precision through windows.

// Basic.cpp : Defines the entry point for the console application.

//

// Basic

// Just makes a basic sound for a few seconds then applies a low pass filter

// Then some effects

#include

<alut.h>

#include

<efx.h>

#include

 <conio.h>

#include

 <stdlib.h>

#include

 <stdio.h>

#include

 <al.h>

#include

 <alc.h>

#include

 <EFX-Util.h>

#include

 <efx-creative.h>

#define

 NULL 0

LPALGENFILTERS alGenFilters;

LPALFILTERI alFilteri;

LPALFILTERF alFilterf;

LPALGENEFFECTS alGenEffects;

LPALEFFECTI alEffecti;

LPALEFFECTF alEffectf;

LPALGENAUXILIARYEFFECTSLOTS alGenAuxiliaryEffectSlots;

LPALAUXILIARYEFFECTSLOTI alAuxiliaryEffectSloti;

LPALISFILTER alIsFilter;

 

int

 main(int argc, char **argv)

{

ALuint helloBuffer, source;

ALuint filter,filtera;

ALuint EffectSlot,ReverbEffect;

ALCcontext *Context;

ALCdevice *Device;

ALCint iSends;

const

 ALCchar *DeviceName;

// Setting up openal

alutInit (&argc, argv);

Context=alcGetCurrentContext();

Device=alcGetContextsDevice(Context);

DeviceName=alcGetString(0,ALC_DEFAULT_DEVICE_SPECIFIER);

//ALC_DEFAULT_ALL_DEVICES_SPECIFIER this was here in henrys code

printf(

"\n\nDevice is %s\n",DeviceName);

// And effects definitions

alGenFilters = (LPALGENFILTERS)alGetProcAddress(

"alGenFilters");

alFilteri=(LPALFILTERI)alGetProcAddress(

"alFilteri");

alFilterf=(LPALFILTERF)alGetProcAddress(

"alFilterf");

alGenEffects=(LPALGENEFFECTS)alGetProcAddress(

"alGenEffects");

alEffecti=(LPALEFFECTI)alGetProcAddress(

"alEffecti");

alEffectf=(LPALEFFECTF)alGetProcAddress(

"alEffectf");

alGenAuxiliaryEffectSlots=(LPALGENAUXILIARYEFFECTSLOTS)alGetProcAddress(

"alGenAuxiliaryEffectSlots");

alAuxiliaryEffectSloti=(LPALAUXILIARYEFFECTSLOTI)alGetProcAddress(

"alAuxiliaryEffectSloti");

alIsFilter= (LPALISFILTER)alGetProcAddress(

"alIsFilter");

// Setup Buffer from input file or helloworld

if(argc==2)

helloBuffer= alutCreateBufferFromFile(argv[1]);

else

helloBuffer = alutCreateBufferHelloWorld ();

// Generate Source and attach buffer

alGenSources(1,&source);

alSourcei(source,AL_BUFFER,helloBuffer);

// Set up some soruce parameters

alSourcei(source, AL_LOOPING, AL_TRUE);

printf(

"\nRaw Source\n");

alSourcePlay (source);

alutSleep(3);

alSourceStop(source);

// Now with a filter

alGetError();

alGenFilters(1,&filter);

if

 (alGetError() == AL_NO_ERROR)

printf(

"Generated Filter %i\n",filter);

alFilteri(filter,AL_FILTER_TYPE,AL_FILTER_LOWPASS);

if

 (alGetError() != AL_NO_ERROR)

printf(

"Low Pass Filter not supported\n");

else

{

alFilterf(filter,AL_LOWPASS_GAIN,0.5);

alFilterf(filter,AL_LOWPASS_GAINHF,0.01);

}

alSourcei(source,AL_DIRECT_FILTER,filter);

if

 (alGetError() == AL_NO_ERROR)

{

printf(

"\nFiltered Source\n");

}

alSourcePlay (source);

alutSleep(3);

alSourceStop(source);


--
Robert Smyth

_______________________________________________
Openal mailing list
Openal@...
http://opensource.creative.com/mailman/listinfo/openal

Re: Adding filters

by Daniel PEACOCK :: Rate this Message:

Reply to Author | View Threaded | Show Only this Message





Hi Robert,

I just built an application using this code and the filter is working
correctly for me (the sound becomes filtered and much quieter).

In the initialization code ...



DeviceName=alcGetString(0,ALC_DEFAULT_DEVICE_SPECIFIER);


//ALC_DEFAULT_ALL_DEVICES_SPECIFIER this was here in henrys code


printf("\n\nDevice is %s\n",DeviceName);


That code will display the name of the *default* device on the system -
which should be the one you opened - but I think the purpose of the log is
to display the device that is being used.  In which case you need to use
the following ...


DeviceName=alcGetString(Device,ALC_DEVICE_SPECIFIER);


printf("\n\nDevice Used is %s\n",DeviceName);



i.e. pass in the device handle and use the ALC_DEVICE_SPECIFIER enum.


What device name is returned?  What versions of the openal32.dll and
wrap_oal.dll files do you have?


Thanks,


Dan
Creative Labs (UK) Ltd.

Notice
The information in this message is confidential and may be legally
privileged.  It is intended solely for the addressee.  Access to this
message by anyone else is unauthorized.  If you are not the intended
recipient,  any disclosure,  copying or distribution of the message,  or
any action taken by you in reliance on it,  is prohibited and may be
unlawful.  If you have received this message in error,  please delete it
and contact the sender immediately.  Thank you.

Creative Labs UK Ltd company number 2658256 registered in England and Wales
at Belmont Road, Belmont Place, Maidenhead, Berkshire, SL6 6TB



                                                                           
             Robert Smyth                                                  
             <macgabhr@...>                                            
             Sent by:                                                   To
             openal-bounces@op         openal@...      
             ensource.creative                                          cc
             .com                                                          
                                                                   Subject
                                       [Openal] Adding filters            
             05/26/2009 10:43                                              
             AM                                                            
                                                                           
                                                                           
                                                                           
                                                                           




Hi,

I am trying to add filters to a raw source using openal. THe code I am
using can be seen below. I have read the sdk ext manual and seem to be
doing everything correctly. The program compiles and I get a correct sound
device to be found and no erros when creating my filter but instead of
playing the filtered source it just repeats what has already been played,
i.e the filter doesnt seem to work. I am using microsoft visual studio 9.0
on a dell precision through windows.


// Basic.cpp : Defines the entry point for the console application.


//


// Basic


// Just makes a basic sound for a few seconds then applies a low pass
filter


// Then some effects


#include


<alut.h>


#include


<efx.h>


#include


<conio.h>


#include


<stdlib.h>


#include


<stdio.h>


#include


<al.h>


#include


<alc.h>


#include


<EFX-Util.h>


#include


<efx-creative.h>


#define


NULL 0


LPALGENFILTERS alGenFilters;


LPALFILTERI alFilteri;


LPALFILTERF alFilterf;


LPALGENEFFECTS alGenEffects;


LPALEFFECTI alEffecti;


LPALEFFECTF alEffectf;


LPALGENAUXILIARYEFFECTSLOTS alGenAuxiliaryEffectSlots;


LPALAUXILIARYEFFECTSLOTI alAuxiliaryEffectSloti;


LPALISFILTER alIsFilter;





int


main(int argc, char **argv)


{


ALuint helloBuffer, source;


ALuint filter,filtera;


ALuint EffectSlot,ReverbEffect;


ALCcontext *Context;


ALCdevice *Device;


ALCint iSends;


const


ALCchar *DeviceName;


// Setting up openal


alutInit (&argc, argv);


Context=alcGetCurrentContext();


Device=alcGetContextsDevice(Context);


DeviceName=alcGetString(0,ALC_DEFAULT_DEVICE_SPECIFIER);


//ALC_DEFAULT_ALL_DEVICES_SPECIFIER this was here in henrys code


printf(


"\n\nDevice is %s\n",DeviceName);


// And effects definitions


alGenFilters = (LPALGENFILTERS)alGetProcAddress(


"alGenFilters");


alFilteri=(LPALFILTERI)alGetProcAddress(


"alFilteri");


alFilterf=(LPALFILTERF)alGetProcAddress(


"alFilterf");


alGenEffects=(LPALGENEFFECTS)alGetProcAddress(


"alGenEffects");


alEffecti=(LPALEFFECTI)alGetProcAddress(


"alEffecti");


alEffectf=(LPALEFFECTF)alGetProcAddress(


"alEffectf");


alGenAuxiliaryEffectSlots=(LPALGENAUXILIARYEFFECTSLOTS)alGetProcAddress(


"alGenAuxiliaryEffectSlots");


alAuxiliaryEffectSloti=(LPALAUXILIARYEFFECTSLOTI)alGetProcAddress(


"alAuxiliaryEffectSloti");


alIsFilter= (LPALISFILTER)alGetProcAddress(


"alIsFilter");


// Setup Buffer from input file or helloworld


if(argc==2)


helloBuffer= alutCreateBufferFromFile(argv[1]);


else


helloBuffer = alutCreateBufferHelloWorld ();


// Generate Source and attach buffer


alGenSources(1,&source);


alSourcei(source,AL_BUFFER,helloBuffer);


// Set up some soruce parameters


alSourcei(source, AL_LOOPING, AL_TRUE);


printf(


"\nRaw Source\n");


alSourcePlay (source);


alutSleep(3);


alSourceStop(source);


// Now with a filter


alGetError();


alGenFilters(1,&filter);


if


(alGetError() == AL_NO_ERROR)


printf(


"Generated Filter %i\n",filter);


alFilteri(filter,AL_FILTER_TYPE,AL_FILTER_LOWPASS);


if


(alGetError() != AL_NO_ERROR)


printf(


"Low Pass Filter not supported\n");


else


{


alFilterf(filter,AL_LOWPASS_GAIN,0.5);


alFilterf(filter,AL_LOWPASS_GAINHF,0.01);


}


alSourcei(source,AL_DIRECT_FILTER,filter);


if


(alGetError() == AL_NO_ERROR)


{


printf(


"\nFiltered Source\n");


}


alSourcePlay (source);


alutSleep(3);


alSourceStop(source);



--
Robert Smyth_______________________________________________
Openal mailing list
Openal@...
http://opensource.creative.com/mailman/listinfo/openal

ForwardSourceID:NT0006C81A


_______________________________________________
Openal mailing list
Openal@...
http://opensource.creative.com/mailman/listinfo/openal
Free embeddable forum powered by Nabble Forum Help