375 lines
14 KiB
C
375 lines
14 KiB
C
/**
|
|
* OpenAL cross platform audio library
|
|
* Copyright (C) 2013 by Mike Gorchak
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Library General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Library General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Library General Public
|
|
* License along with this library; if not, write to the
|
|
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
* Boston, MA 02111-1307, USA.
|
|
* Or go to http://www.gnu.org/copyleft/lgpl.html
|
|
*/
|
|
|
|
#include "config.h"
|
|
|
|
#include <math.h>
|
|
#include <stdlib.h>
|
|
|
|
#include "alMain.h"
|
|
#include "alFilter.h"
|
|
#include "alAuxEffectSlot.h"
|
|
#include "alError.h"
|
|
#include "alu.h"
|
|
|
|
|
|
typedef struct ALequalizerStateFactory {
|
|
DERIVE_FROM_TYPE(ALeffectStateFactory);
|
|
} ALequalizerStateFactory;
|
|
|
|
static ALequalizerStateFactory EqualizerFactory;
|
|
|
|
|
|
/* The document "Effects Extension Guide.pdf" says that low and high *
|
|
* frequencies are cutoff frequencies. This is not fully correct, they *
|
|
* are corner frequencies for low and high shelf filters. If they were *
|
|
* just cutoff frequencies, there would be no need in cutoff frequency *
|
|
* gains, which are present. Documentation for "Creative Proteus X2" *
|
|
* software describes 4-band equalizer functionality in a much better *
|
|
* way. This equalizer seems to be a predecessor of OpenAL 4-band *
|
|
* equalizer. With low and high shelf filters we are able to cutoff *
|
|
* frequencies below and/or above corner frequencies using attenuation *
|
|
* gains (below 1.0) and amplify all low and/or high frequencies using *
|
|
* gains above 1.0. *
|
|
* *
|
|
* Low-shelf Low Mid Band High Mid Band High-shelf *
|
|
* corner center center corner *
|
|
* frequency frequency frequency frequency *
|
|
* 50Hz..800Hz 200Hz..3000Hz 1000Hz..8000Hz 4000Hz..16000Hz *
|
|
* *
|
|
* | | | | *
|
|
* | | | | *
|
|
* B -----+ /--+--\ /--+--\ +----- *
|
|
* O |\ | | | | | | /| *
|
|
* O | \ - | - - | - / | *
|
|
* S + | \ | | | | | | / | *
|
|
* T | | | | | | | | | | *
|
|
* ---------+---------------+------------------+---------------+-------- *
|
|
* C | | | | | | | | | | *
|
|
* U - | / | | | | | | \ | *
|
|
* T | / - | - - | - \ | *
|
|
* O |/ | | | | | | \| *
|
|
* F -----+ \--+--/ \--+--/ +----- *
|
|
* F | | | | *
|
|
* | | | | *
|
|
* *
|
|
* Gains vary from 0.126 up to 7.943, which means from -18dB attenuation *
|
|
* up to +18dB amplification. Band width varies from 0.01 up to 1.0 in *
|
|
* octaves for two mid bands. *
|
|
* *
|
|
* Implementation is based on the "Cookbook formulae for audio EQ biquad *
|
|
* filter coefficients" by Robert Bristow-Johnson *
|
|
* http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt */
|
|
|
|
typedef struct ALequalizerState {
|
|
DERIVE_FROM_TYPE(ALeffectState);
|
|
|
|
/* Effect gains for each channel */
|
|
ALfloat Gain[MaxChannels];
|
|
|
|
/* Effect parameters */
|
|
ALfilterState filter[4];
|
|
} ALequalizerState;
|
|
|
|
static ALvoid ALequalizerState_Destruct(ALequalizerState *state)
|
|
{
|
|
(void)state;
|
|
}
|
|
|
|
static ALboolean ALequalizerState_DeviceUpdate(ALequalizerState *state, ALCdevice *device)
|
|
{
|
|
return AL_TRUE;
|
|
(void)state;
|
|
(void)device;
|
|
}
|
|
|
|
static ALvoid ALequalizerState_Update(ALequalizerState *state, ALCdevice *device, const ALeffectslot *slot)
|
|
{
|
|
ALfloat frequency = (ALfloat)device->Frequency;
|
|
ALfloat gain = sqrtf(1.0f / device->NumChan) * slot->Gain;
|
|
ALuint it;
|
|
|
|
for(it = 0;it < MaxChannels;it++)
|
|
state->Gain[it] = 0.0f;
|
|
for(it = 0; it < device->NumChan; it++)
|
|
{
|
|
enum Channel chan = device->Speaker2Chan[it];
|
|
state->Gain[chan] = gain;
|
|
}
|
|
|
|
/* Calculate coefficients for the each type of filter */
|
|
for(it = 0; it < 4; it++)
|
|
{
|
|
ALfilterType type = ALfilterType_Peaking;
|
|
ALfloat filter_frequency;
|
|
ALfloat bandwidth = 0.0f;
|
|
ALfloat gain;
|
|
|
|
/* convert linear gains to filter gains */
|
|
switch(it)
|
|
{
|
|
case 0: /* Low Shelf */
|
|
gain = sqrtf(slot->EffectProps.Equalizer.LowGain);
|
|
filter_frequency = slot->EffectProps.Equalizer.LowCutoff;
|
|
type = ALfilterType_LowShelf;
|
|
break;
|
|
case 1: /* Peaking */
|
|
gain = sqrtf(slot->EffectProps.Equalizer.Mid1Gain);
|
|
filter_frequency = slot->EffectProps.Equalizer.Mid1Center;
|
|
bandwidth = slot->EffectProps.Equalizer.Mid1Width;
|
|
type = ALfilterType_Peaking;
|
|
break;
|
|
case 2: /* Peaking */
|
|
gain = sqrtf(slot->EffectProps.Equalizer.Mid2Gain);
|
|
filter_frequency = slot->EffectProps.Equalizer.Mid2Center;
|
|
bandwidth = slot->EffectProps.Equalizer.Mid2Width;
|
|
type = ALfilterType_Peaking;
|
|
break;
|
|
case 3: /* High Shelf */
|
|
gain = sqrtf(slot->EffectProps.Equalizer.HighGain);
|
|
filter_frequency = slot->EffectProps.Equalizer.HighCutoff;
|
|
type = ALfilterType_HighShelf;
|
|
break;
|
|
}
|
|
|
|
ALfilterState_setParams(&state->filter[it], type, gain, filter_frequency/frequency, bandwidth);
|
|
}
|
|
}
|
|
|
|
static ALvoid ALequalizerState_Process(ALequalizerState *state, ALuint SamplesToDo, const ALfloat *restrict SamplesIn, ALfloat (*restrict SamplesOut)[BUFFERSIZE])
|
|
{
|
|
ALuint base;
|
|
ALuint it;
|
|
ALuint kt;
|
|
ALuint ft;
|
|
|
|
for(base = 0;base < SamplesToDo;)
|
|
{
|
|
ALfloat temps[64];
|
|
ALuint td = minu(SamplesToDo-base, 64);
|
|
|
|
for(it = 0;it < td;it++)
|
|
{
|
|
ALfloat smp = SamplesIn[base+it];
|
|
|
|
for(ft = 0;ft < 4;ft++)
|
|
smp = ALfilterState_processSingle(&state->filter[ft], smp);
|
|
|
|
temps[it] = smp;
|
|
}
|
|
|
|
for(kt = 0;kt < MaxChannels;kt++)
|
|
{
|
|
ALfloat gain = state->Gain[kt];
|
|
if(!(gain > 0.00001f))
|
|
continue;
|
|
|
|
for(it = 0;it < td;it++)
|
|
SamplesOut[kt][base+it] += gain * temps[it];
|
|
}
|
|
|
|
base += td;
|
|
}
|
|
}
|
|
|
|
static void ALequalizerState_Delete(ALequalizerState *state)
|
|
{
|
|
free(state);
|
|
}
|
|
|
|
DEFINE_ALEFFECTSTATE_VTABLE(ALequalizerState);
|
|
|
|
|
|
ALeffectState *ALequalizerStateFactory_create(ALequalizerStateFactory *factory)
|
|
{
|
|
ALequalizerState *state;
|
|
int it;
|
|
(void)factory;
|
|
|
|
state = malloc(sizeof(*state));
|
|
if(!state) return NULL;
|
|
SET_VTABLE2(ALequalizerState, ALeffectState, state);
|
|
|
|
/* Initialize sample history only on filter creation to avoid */
|
|
/* sound clicks if filter settings were changed in runtime. */
|
|
for(it = 0; it < 4; it++)
|
|
ALfilterState_clear(&state->filter[it]);
|
|
|
|
return STATIC_CAST(ALeffectState, state);
|
|
}
|
|
|
|
DEFINE_ALEFFECTSTATEFACTORY_VTABLE(ALequalizerStateFactory);
|
|
|
|
|
|
static void init_equalizer_factory(void)
|
|
{
|
|
SET_VTABLE2(ALequalizerStateFactory, ALeffectStateFactory, &EqualizerFactory);
|
|
}
|
|
|
|
ALeffectStateFactory *ALequalizerStateFactory_getFactory(void)
|
|
{
|
|
static pthread_once_t once = PTHREAD_ONCE_INIT;
|
|
pthread_once(&once, init_equalizer_factory);
|
|
return STATIC_CAST(ALeffectStateFactory, &EqualizerFactory);
|
|
}
|
|
|
|
|
|
void ALequalizer_SetParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val)
|
|
{ SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM); (void)effect;(void)param;(void)val; }
|
|
void ALequalizer_SetParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals)
|
|
{
|
|
ALequalizer_SetParami(effect, context, param, vals[0]);
|
|
}
|
|
void ALequalizer_SetParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val)
|
|
{
|
|
ALeffectProps *props = &effect->Props;
|
|
switch(param)
|
|
{
|
|
case AL_EQUALIZER_LOW_GAIN:
|
|
if(!(val >= AL_EQUALIZER_MIN_LOW_GAIN && val <= AL_EQUALIZER_MAX_LOW_GAIN))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.LowGain = val;
|
|
break;
|
|
|
|
case AL_EQUALIZER_LOW_CUTOFF:
|
|
if(!(val >= AL_EQUALIZER_MIN_LOW_CUTOFF && val <= AL_EQUALIZER_MAX_LOW_CUTOFF))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.LowCutoff = val;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID1_GAIN:
|
|
if(!(val >= AL_EQUALIZER_MIN_MID1_GAIN && val <= AL_EQUALIZER_MAX_MID1_GAIN))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.Mid1Gain = val;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID1_CENTER:
|
|
if(!(val >= AL_EQUALIZER_MIN_MID1_CENTER && val <= AL_EQUALIZER_MAX_MID1_CENTER))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.Mid1Center = val;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID1_WIDTH:
|
|
if(!(val >= AL_EQUALIZER_MIN_MID1_WIDTH && val <= AL_EQUALIZER_MAX_MID1_WIDTH))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.Mid1Width = val;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID2_GAIN:
|
|
if(!(val >= AL_EQUALIZER_MIN_MID2_GAIN && val <= AL_EQUALIZER_MAX_MID2_GAIN))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.Mid2Gain = val;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID2_CENTER:
|
|
if(!(val >= AL_EQUALIZER_MIN_MID2_CENTER && val <= AL_EQUALIZER_MAX_MID2_CENTER))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.Mid2Center = val;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID2_WIDTH:
|
|
if(!(val >= AL_EQUALIZER_MIN_MID2_WIDTH && val <= AL_EQUALIZER_MAX_MID2_WIDTH))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.Mid2Width = val;
|
|
break;
|
|
|
|
case AL_EQUALIZER_HIGH_GAIN:
|
|
if(!(val >= AL_EQUALIZER_MIN_HIGH_GAIN && val <= AL_EQUALIZER_MAX_HIGH_GAIN))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.HighGain = val;
|
|
break;
|
|
|
|
case AL_EQUALIZER_HIGH_CUTOFF:
|
|
if(!(val >= AL_EQUALIZER_MIN_HIGH_CUTOFF && val <= AL_EQUALIZER_MAX_HIGH_CUTOFF))
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
|
|
props->Equalizer.HighCutoff = val;
|
|
break;
|
|
|
|
default:
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
|
|
}
|
|
}
|
|
void ALequalizer_SetParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals)
|
|
{
|
|
ALequalizer_SetParamf(effect, context, param, vals[0]);
|
|
}
|
|
|
|
void ALequalizer_GetParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint *val)
|
|
{ SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM); (void)effect;(void)param;(void)val; }
|
|
void ALequalizer_GetParamiv(ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals)
|
|
{
|
|
ALequalizer_GetParami(effect, context, param, vals);
|
|
}
|
|
void ALequalizer_GetParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val)
|
|
{
|
|
const ALeffectProps *props = &effect->Props;
|
|
switch(param)
|
|
{
|
|
case AL_EQUALIZER_LOW_GAIN:
|
|
*val = props->Equalizer.LowGain;
|
|
break;
|
|
|
|
case AL_EQUALIZER_LOW_CUTOFF:
|
|
*val = props->Equalizer.LowCutoff;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID1_GAIN:
|
|
*val = props->Equalizer.Mid1Gain;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID1_CENTER:
|
|
*val = props->Equalizer.Mid1Center;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID1_WIDTH:
|
|
*val = props->Equalizer.Mid1Width;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID2_GAIN:
|
|
*val = props->Equalizer.Mid2Gain;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID2_CENTER:
|
|
*val = props->Equalizer.Mid2Center;
|
|
break;
|
|
|
|
case AL_EQUALIZER_MID2_WIDTH:
|
|
*val = props->Equalizer.Mid2Width;
|
|
break;
|
|
|
|
case AL_EQUALIZER_HIGH_GAIN:
|
|
*val = props->Equalizer.HighGain;
|
|
break;
|
|
|
|
case AL_EQUALIZER_HIGH_CUTOFF:
|
|
*val = props->Equalizer.HighCutoff;
|
|
break;
|
|
|
|
default:
|
|
SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
|
|
}
|
|
}
|
|
void ALequalizer_GetParamfv(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals)
|
|
{
|
|
ALequalizer_GetParamf(effect, context, param, vals);
|
|
}
|
|
|
|
DEFINE_ALEFFECT_VTABLE(ALequalizer);
|