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Diffstat (limited to 'Alc/alcEqualizer.c')
| -rw-r--r-- | Alc/alcEqualizer.c | 499 |
1 files changed, 0 insertions, 499 deletions
diff --git a/Alc/alcEqualizer.c b/Alc/alcEqualizer.c deleted file mode 100644 index d397a9ba..00000000 --- a/Alc/alcEqualizer.c +++ /dev/null @@ -1,499 +0,0 @@ -/** - * 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 enum ALEQFilterType { - LOW_SHELF, - HIGH_SHELF, - PEAKING -} ALEQFilterType; - -typedef struct ALEQFilter { - ALEQFilterType type; - ALfloat x[2]; /* History of two last input samples */ - ALfloat y[2]; /* History of two last output samples */ - ALfloat a[3]; /* Transfer function coefficients "a" */ - ALfloat b[3]; /* Transfer function coefficients "b" */ -} ALEQFilter; - -typedef struct ALequalizerState { - DERIVE_FROM_TYPE(ALeffectState); - - /* Effect gains for each channel */ - ALfloat Gain[MaxChannels]; - - /* Effect parameters */ - ALEQFilter bandfilter[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++) - { - ALfloat gain; - ALfloat filter_frequency; - ALfloat bandwidth = 0.0f; - ALfloat w0; - ALfloat alpha = 0.0f; - - /* convert linear gains to filter gains */ - switch (it) - { - case 0: /* Low Shelf */ - gain = powf(10.0f, (20.0f * log10f(slot->effect.Equalizer.LowGain)) / 40.0f); - filter_frequency = slot->effect.Equalizer.LowCutoff; - break; - case 1: /* Peaking */ - gain = powf(10.0f, (20.0f * log10f(slot->effect.Equalizer.Mid1Gain)) / 40.0f); - filter_frequency = slot->effect.Equalizer.Mid1Center; - bandwidth = slot->effect.Equalizer.Mid1Width; - break; - case 2: /* Peaking */ - gain = powf(10.0f, (20.0f * log10f(slot->effect.Equalizer.Mid2Gain)) / 40.0f); - filter_frequency = slot->effect.Equalizer.Mid2Center; - bandwidth = slot->effect.Equalizer.Mid2Width; - break; - case 3: /* High Shelf */ - gain = powf(10.0f, (20.0f * log10f(slot->effect.Equalizer.HighGain)) / 40.0f); - filter_frequency = slot->effect.Equalizer.HighCutoff; - break; - } - - w0 = 2.0f*F_PI * filter_frequency / frequency; - - /* Calculate filter coefficients depending on filter type */ - switch(state->bandfilter[it].type) - { - case LOW_SHELF: - alpha = sinf(w0) / 2.0f * sqrtf((gain + 1.0f / gain) * - (1.0f / 0.75f - 1.0f) + 2.0f); - state->bandfilter[it].b[0] = gain * ((gain + 1.0f) - - (gain - 1.0f) * cosf(w0) + - 2.0f * sqrtf(gain) * alpha); - state->bandfilter[it].b[1] = 2.0f * gain * ((gain - 1.0f) - - (gain + 1.0f) * cosf(w0)); - state->bandfilter[it].b[2] = gain * ((gain + 1.0f) - - (gain - 1.0f) * cosf(w0) - - 2.0f * sqrtf(gain) * alpha); - state->bandfilter[it].a[0] = (gain + 1.0f) + - (gain - 1.0f) * cosf(w0) + - 2.0f * sqrtf(gain) * alpha; - state->bandfilter[it].a[1] = -2.0f * ((gain - 1.0f) + - (gain + 1.0f) * cosf(w0)); - state->bandfilter[it].a[2] = (gain + 1.0f) + - (gain - 1.0f) * cosf(w0) - - 2.0f * sqrtf(gain) * alpha; - break; - case HIGH_SHELF: - alpha = sinf(w0) / 2.0f * sqrtf((gain + 1.0f / gain) * - (1.0f / 0.75f - 1.0f) + 2.0f); - state->bandfilter[it].b[0] = gain * ((gain + 1.0f) + - (gain - 1.0f) * cosf(w0) + - 2.0f * sqrtf(gain) * alpha); - state->bandfilter[it].b[1] = -2.0f * gain * ((gain - 1.0f) + - (gain + 1.0f) * - cosf(w0)); - state->bandfilter[it].b[2] = gain * ((gain + 1.0f) + - (gain - 1.0f) * cosf(w0) - - 2.0f * sqrtf(gain) * alpha); - state->bandfilter[it].a[0] = (gain + 1.0f) - - (gain - 1.0f) * cosf(w0) + - 2.0f * sqrtf(gain) * alpha; - state->bandfilter[it].a[1] = 2.0f * ((gain - 1.0f) - - (gain + 1.0f) * cosf(w0)); - state->bandfilter[it].a[2] = (gain + 1.0f) - - (gain - 1.0f) * cosf(w0) - - 2.0f * sqrtf(gain) * alpha; - break; - case PEAKING: - alpha = sinf(w0) * sinhf(logf(2.0f) / 2.0f * bandwidth * w0 / sinf(w0)); - state->bandfilter[it].b[0] = 1.0f + alpha * gain; - state->bandfilter[it].b[1] = -2.0f * cosf(w0); - state->bandfilter[it].b[2] = 1.0f - alpha * gain; - state->bandfilter[it].a[0] = 1.0f + alpha / gain; - state->bandfilter[it].a[1] = -2.0f * cosf(w0); - state->bandfilter[it].a[2] = 1.0f - alpha / gain; - break; - } - } -} - -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]; - ALfloat tempsmp; - - for(ft = 0;ft < 4;ft++) - { - ALEQFilter *filter = &state->bandfilter[ft]; - - tempsmp = filter->b[0] / filter->a[0] * smp + - filter->b[1] / filter->a[0] * filter->x[0] + - filter->b[2] / filter->a[0] * filter->x[1] - - filter->a[1] / filter->a[0] * filter->y[0] - - filter->a[2] / filter->a[0] * filter->y[1]; - - filter->x[1] = filter->x[0]; - filter->x[0] = smp; - filter->y[1] = filter->y[0]; - filter->y[0] = tempsmp; - smp = tempsmp; - } - - 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 ALeffectStateFactory *ALequalizerState_getCreator(void) -{ - return STATIC_CAST(ALeffectStateFactory, &EqualizerFactory); -} - -DEFINE_ALEFFECTSTATE_VTABLE(ALequalizerState); - - -ALeffectState *ALequalizerStateFactory_create(void) -{ - ALequalizerState *state; - int it; - - state = malloc(sizeof(*state)); - if(!state) return NULL; - SET_VTABLE2(ALequalizerState, ALeffectState, state); - - state->bandfilter[0].type = LOW_SHELF; - state->bandfilter[1].type = PEAKING; - state->bandfilter[2].type = PEAKING; - state->bandfilter[3].type = HIGH_SHELF; - - /* Initialize sample history only on filter creation to avoid */ - /* sound clicks if filter settings were changed in runtime. */ - for(it = 0; it < 4; it++) - { - state->bandfilter[it].x[0] = 0.0f; - state->bandfilter[it].x[1] = 0.0f; - state->bandfilter[it].y[0] = 0.0f; - state->bandfilter[it].y[1] = 0.0f; - } - - return STATIC_CAST(ALeffectState, state); -} - -static ALvoid ALequalizerStateFactory_destroy(ALeffectState *effect) -{ - ALequalizerState *state = STATIC_UPCAST(ALequalizerState, ALeffectState, effect); - ALequalizerState_Destruct(state); - free(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 equalizer_SetParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val) -{ - effect=effect; - val=val; - - switch(param) - { - default: - alSetError(context, AL_INVALID_ENUM); - break; - } -} -void equalizer_SetParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals) -{ - equalizer_SetParami(effect, context, param, vals[0]); -} -void equalizer_SetParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val) -{ - switch(param) - { - case AL_EQUALIZER_LOW_GAIN: - if(val >= AL_EQUALIZER_MIN_LOW_GAIN && val <= AL_EQUALIZER_MAX_LOW_GAIN) - effect->Equalizer.LowGain = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - case AL_EQUALIZER_LOW_CUTOFF: - if(val >= AL_EQUALIZER_MIN_LOW_CUTOFF && val <= AL_EQUALIZER_MAX_LOW_CUTOFF) - effect->Equalizer.LowCutoff = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - case AL_EQUALIZER_MID1_GAIN: - if(val >= AL_EQUALIZER_MIN_MID1_GAIN && val <= AL_EQUALIZER_MAX_MID1_GAIN) - effect->Equalizer.Mid1Gain = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - case AL_EQUALIZER_MID1_CENTER: - if(val >= AL_EQUALIZER_MIN_MID1_CENTER && val <= AL_EQUALIZER_MAX_MID1_CENTER) - effect->Equalizer.Mid1Center = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - case AL_EQUALIZER_MID1_WIDTH: - if(val >= AL_EQUALIZER_MIN_MID1_WIDTH && val <= AL_EQUALIZER_MAX_MID1_WIDTH) - effect->Equalizer.Mid1Width = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - case AL_EQUALIZER_MID2_GAIN: - if(val >= AL_EQUALIZER_MIN_MID2_GAIN && val <= AL_EQUALIZER_MAX_MID2_GAIN) - effect->Equalizer.Mid2Gain = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - case AL_EQUALIZER_MID2_CENTER: - if(val >= AL_EQUALIZER_MIN_MID2_CENTER && val <= AL_EQUALIZER_MAX_MID2_CENTER) - effect->Equalizer.Mid2Center = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - case AL_EQUALIZER_MID2_WIDTH: - if(val >= AL_EQUALIZER_MIN_MID2_WIDTH && val <= AL_EQUALIZER_MAX_MID2_WIDTH) - effect->Equalizer.Mid2Width = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - case AL_EQUALIZER_HIGH_GAIN: - if(val >= AL_EQUALIZER_MIN_HIGH_GAIN && val <= AL_EQUALIZER_MAX_HIGH_GAIN) - effect->Equalizer.HighGain = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - case AL_EQUALIZER_HIGH_CUTOFF: - if(val >= AL_EQUALIZER_MIN_HIGH_CUTOFF && val <= AL_EQUALIZER_MAX_HIGH_CUTOFF) - effect->Equalizer.HighCutoff = val; - else - alSetError(context, AL_INVALID_VALUE); - break; - - default: - alSetError(context, AL_INVALID_ENUM); - break; - } -} -void equalizer_SetParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals) -{ - equalizer_SetParamf(effect, context, param, vals[0]); -} - -void equalizer_GetParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint *val) -{ - effect=effect; - val=val; - - switch(param) - { - default: - alSetError(context, AL_INVALID_ENUM); - break; - } -} -void equalizer_GetParamiv(ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals) -{ - equalizer_GetParami(effect, context, param, vals); -} -void equalizer_GetParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val) -{ - switch(param) - { - case AL_EQUALIZER_LOW_GAIN: - *val = effect->Equalizer.LowGain; - break; - - case AL_EQUALIZER_LOW_CUTOFF: - *val = effect->Equalizer.LowCutoff; - break; - - case AL_EQUALIZER_MID1_GAIN: - *val = effect->Equalizer.Mid1Gain; - break; - - case AL_EQUALIZER_MID1_CENTER: - *val = effect->Equalizer.Mid1Center; - break; - - case AL_EQUALIZER_MID1_WIDTH: - *val = effect->Equalizer.Mid1Width; - break; - - case AL_EQUALIZER_MID2_GAIN: - *val = effect->Equalizer.Mid2Gain; - break; - - case AL_EQUALIZER_MID2_CENTER: - *val = effect->Equalizer.Mid2Center; - break; - - case AL_EQUALIZER_MID2_WIDTH: - *val = effect->Equalizer.Mid2Width; - break; - - case AL_EQUALIZER_HIGH_GAIN: - *val = effect->Equalizer.HighGain; - break; - - case AL_EQUALIZER_HIGH_CUTOFF: - *val = effect->Equalizer.HighCutoff; - break; - - default: - alSetError(context, AL_INVALID_ENUM); - break; - } -} -void equalizer_GetParamfv(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals) -{ - equalizer_GetParamf(effect, context, param, vals); -} |