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Diffstat (limited to 'Alc/effects/compressor.c')
| -rw-r--r-- | Alc/effects/compressor.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/Alc/effects/compressor.c b/Alc/effects/compressor.c new file mode 100644 index 00000000..14c0ed10 --- /dev/null +++ b/Alc/effects/compressor.c @@ -0,0 +1,223 @@ +/** + * OpenAL cross platform audio library + * Copyright (C) 2013 by Anis A. Hireche + * 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 <stdlib.h> + +#include "config.h" +#include "alError.h" +#include "alMain.h" +#include "alAuxEffectSlot.h" +#include "alu.h" + + +typedef struct ALcompressorState { + DERIVE_FROM_TYPE(ALeffectState); + + /* Effect gains for each channel */ + ALfloat Gain[MaxChannels]; + + /* Effect parameters */ + ALboolean Enabled; + ALfloat AttackRate; + ALfloat ReleaseRate; + ALfloat GainCtrl; +} ALcompressorState; + +static ALvoid ALcompressorState_Destruct(ALcompressorState *UNUSED(state)) +{ +} + +static ALboolean ALcompressorState_deviceUpdate(ALcompressorState *state, ALCdevice *device) +{ + const ALfloat attackTime = device->Frequency * 0.2f; /* 200ms Attack */ + const ALfloat releaseTime = device->Frequency * 0.4f; /* 400ms Release */ + + state->AttackRate = 1.0f / attackTime; + state->ReleaseRate = 1.0f / releaseTime; + + return AL_TRUE; +} + +static ALvoid ALcompressorState_update(ALcompressorState *state, ALCdevice *Device, const ALeffectslot *Slot) +{ + ALfloat gain; + + state->Enabled = Slot->EffectProps.Compressor.OnOff; + + gain = sqrtf(1.0f / Device->NumChan) * Slot->Gain; + SetGains(Device, gain, state->Gain); +} + +static ALvoid ALcompressorState_process(ALcompressorState *state, ALuint SamplesToDo, const ALfloat *SamplesIn, ALfloat (*SamplesOut)[BUFFERSIZE]) +{ + ALuint it, kt; + ALuint base; + + for(base = 0;base < SamplesToDo;) + { + ALfloat temps[64]; + ALuint td = minu(SamplesToDo-base, 64); + + if(state->Enabled) + { + ALfloat output, smp, amplitude; + ALfloat gain = state->GainCtrl; + + for(it = 0;it < td;it++) + { + smp = SamplesIn[it+base]; + + amplitude = fabs(smp); + if(amplitude > gain) + gain = minf(gain+state->AttackRate, amplitude); + else if(amplitude < gain) + gain = maxf(gain-state->ReleaseRate, amplitude); + output = 1.0 / clampf(gain, 0.5f, 2.0f); + + temps[it] = smp * output; + } + + state->GainCtrl = gain; + } + else + { + ALfloat output, smp, amplitude; + ALfloat gain = state->GainCtrl; + + for(it = 0;it < td;it++) + { + smp = SamplesIn[it+base]; + + amplitude = 1.0f; + if(amplitude > gain) + gain = minf(gain+state->AttackRate, amplitude); + else if(amplitude < gain) + gain = maxf(gain-state->ReleaseRate, amplitude); + output = 1.0f / clampf(gain, 0.5f, 2.0f); + + temps[it] = smp * output; + } + + state->GainCtrl = gain; + } + + + for(kt = 0;kt < MaxChannels;kt++) + { + ALfloat gain = state->Gain[kt]; + if(!(gain > GAIN_SILENCE_THRESHOLD)) + continue; + + for(it = 0;it < td;it++) + SamplesOut[kt][base+it] += gain * temps[it]; + } + + base += td; + } +} + +static void ALcompressorState_Delete(ALcompressorState *state) +{ + free(state); +} + +DEFINE_ALEFFECTSTATE_VTABLE(ALcompressorState); + + +typedef struct ALcompressorStateFactory { + DERIVE_FROM_TYPE(ALeffectStateFactory); +} ALcompressorStateFactory; + +static ALeffectState *ALcompressorStateFactory_create(ALcompressorStateFactory *UNUSED(factory)) +{ + ALcompressorState *state; + + state = malloc(sizeof(*state)); + if(!state) return NULL; + SET_VTABLE2(ALcompressorState, ALeffectState, state); + + state->Enabled = AL_TRUE; + state->AttackRate = 0.0f; + state->ReleaseRate = 0.0f; + state->GainCtrl = 1.0f; + + return STATIC_CAST(ALeffectState, state); +} + +DEFINE_ALEFFECTSTATEFACTORY_VTABLE(ALcompressorStateFactory); + +ALeffectStateFactory *ALcompressorStateFactory_getFactory(void) +{ + static ALcompressorStateFactory CompressorFactory = { { GET_VTABLE2(ALcompressorStateFactory, ALeffectStateFactory) } }; + + return STATIC_CAST(ALeffectStateFactory, &CompressorFactory); +} + + +void ALcompressor_setParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val) +{ + ALeffectProps *props = &effect->Props; + switch(param) + { + case AL_COMPRESSOR_ONOFF: + if(!(val >= AL_COMPRESSOR_MIN_ONOFF && val <= AL_COMPRESSOR_MAX_ONOFF)) + SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE); + props->Compressor.OnOff = val; + break; + + default: + SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM); + } +} +void ALcompressor_setParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals) +{ + ALcompressor_setParami(effect, context, param, vals[0]); +} +void ALcompressor_setParamf(ALeffect *UNUSED(effect), ALCcontext *context, ALenum UNUSED(param), ALfloat UNUSED(val)) +{ SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM); } +void ALcompressor_setParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals) +{ + ALcompressor_setParamf(effect, context, param, vals[0]); +} + +void ALcompressor_getParami(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *val) +{ + const ALeffectProps *props = &effect->Props; + switch(param) + { + case AL_COMPRESSOR_ONOFF: + *val = props->Compressor.OnOff; + break; + default: + SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM); + } +} +void ALcompressor_getParamiv(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals) +{ + ALcompressor_getParami(effect, context, param, vals); +} +void ALcompressor_getParamf(const ALeffect *UNUSED(effect), ALCcontext *context, ALenum UNUSED(param), ALfloat *UNUSED(val)) +{ SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM); } +void ALcompressor_getParamfv(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals) +{ + ALcompressor_getParamf(effect, context, param, vals); +} + +DEFINE_ALEFFECT_VTABLE(ALcompressor); |