diff options
author | Chris Robinson <[email protected]> | 2018-11-17 06:53:20 -0800 |
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committer | Chris Robinson <[email protected]> | 2018-11-17 06:53:20 -0800 |
commit | 93d96ced9cef7200b04dbfec51325a3c9c55af19 (patch) | |
tree | efea25569bc6e5df48a4837ad276a96cc6e44c3c /Alc/effects/equalizer.cpp | |
parent | ad34855a2bb9312d3f21ff3fdca20bca767b9224 (diff) |
Convert the dedicated, distortion, echo, and equalizer to C++
Diffstat (limited to 'Alc/effects/equalizer.cpp')
-rw-r--r-- | Alc/effects/equalizer.cpp | 359 |
1 files changed, 359 insertions, 0 deletions
diff --git a/Alc/effects/equalizer.cpp b/Alc/effects/equalizer.cpp new file mode 100644 index 00000000..8388a123 --- /dev/null +++ b/Alc/effects/equalizer.cpp @@ -0,0 +1,359 @@ +/** + * 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., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * Or go to http://www.gnu.org/copyleft/lgpl.html + */ + +#include "config.h" + +#include <math.h> +#include <stdlib.h> + +#include "alMain.h" +#include "alAuxEffectSlot.h" +#include "alError.h" +#include "alu.h" +#include "filters/defs.h" + + +/* 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 */ + + +struct ALequalizerState final : public ALeffectState { + struct { + /* Effect parameters */ + BiquadFilter filter[4]; + + /* Effect gains for each channel */ + ALfloat CurrentGains[MAX_OUTPUT_CHANNELS]; + ALfloat TargetGains[MAX_OUTPUT_CHANNELS]; + } Chans[MAX_EFFECT_CHANNELS]; + + ALfloat SampleBuffer[MAX_EFFECT_CHANNELS][BUFFERSIZE]; +}; + +static ALvoid ALequalizerState_Destruct(ALequalizerState *state); +static ALboolean ALequalizerState_deviceUpdate(ALequalizerState *state, ALCdevice *device); +static ALvoid ALequalizerState_update(ALequalizerState *state, const ALCcontext *context, const ALeffectslot *slot, const ALeffectProps *props); +static ALvoid ALequalizerState_process(ALequalizerState *state, ALsizei SamplesToDo, const ALfloat (*RESTRICT SamplesIn)[BUFFERSIZE], ALfloat (*RESTRICT SamplesOut)[BUFFERSIZE], ALsizei NumChannels); +DECLARE_DEFAULT_ALLOCATORS(ALequalizerState) + +DEFINE_ALEFFECTSTATE_VTABLE(ALequalizerState); + + +static void ALequalizerState_Construct(ALequalizerState *state) +{ + new (state) ALequalizerState{}; + ALeffectState_Construct(STATIC_CAST(ALeffectState, state)); + SET_VTABLE2(ALequalizerState, ALeffectState, state); +} + +static ALvoid ALequalizerState_Destruct(ALequalizerState *state) +{ + ALeffectState_Destruct(STATIC_CAST(ALeffectState,state)); + state->~ALequalizerState(); +} + +static ALboolean ALequalizerState_deviceUpdate(ALequalizerState *state, ALCdevice *UNUSED(device)) +{ + ALsizei i, j; + + for(i = 0; i < MAX_EFFECT_CHANNELS;i++) + { + for(j = 0;j < 4;j++) + BiquadFilter_clear(&state->Chans[i].filter[j]); + for(j = 0;j < MAX_OUTPUT_CHANNELS;j++) + state->Chans[i].CurrentGains[j] = 0.0f; + } + return AL_TRUE; +} + +static ALvoid ALequalizerState_update(ALequalizerState *state, const ALCcontext *context, const ALeffectslot *slot, const ALeffectProps *props) +{ + const ALCdevice *device = context->Device; + ALfloat frequency = (ALfloat)device->Frequency; + ALfloat gain, f0norm; + ALuint i; + + /* Calculate coefficients for the each type of filter. Note that the shelf + * filters' gain is for the reference frequency, which is the centerpoint + * of the transition band. + */ + gain = maxf(sqrtf(props->Equalizer.LowGain), 0.0625f); /* Limit -24dB */ + f0norm = props->Equalizer.LowCutoff/frequency; + BiquadFilter_setParams(&state->Chans[0].filter[0], BiquadType_LowShelf, + gain, f0norm, calc_rcpQ_from_slope(gain, 0.75f) + ); + + gain = maxf(props->Equalizer.Mid1Gain, 0.0625f); + f0norm = props->Equalizer.Mid1Center/frequency; + BiquadFilter_setParams(&state->Chans[0].filter[1], BiquadType_Peaking, + gain, f0norm, calc_rcpQ_from_bandwidth( + f0norm, props->Equalizer.Mid1Width + ) + ); + + gain = maxf(props->Equalizer.Mid2Gain, 0.0625f); + f0norm = props->Equalizer.Mid2Center/frequency; + BiquadFilter_setParams(&state->Chans[0].filter[2], BiquadType_Peaking, + gain, f0norm, calc_rcpQ_from_bandwidth( + f0norm, props->Equalizer.Mid2Width + ) + ); + + gain = maxf(sqrtf(props->Equalizer.HighGain), 0.0625f); + f0norm = props->Equalizer.HighCutoff/frequency; + BiquadFilter_setParams(&state->Chans[0].filter[3], BiquadType_HighShelf, + gain, f0norm, calc_rcpQ_from_slope(gain, 0.75f) + ); + + /* Copy the filter coefficients for the other input channels. */ + for(i = 1;i < MAX_EFFECT_CHANNELS;i++) + { + BiquadFilter_copyParams(&state->Chans[i].filter[0], &state->Chans[0].filter[0]); + BiquadFilter_copyParams(&state->Chans[i].filter[1], &state->Chans[0].filter[1]); + BiquadFilter_copyParams(&state->Chans[i].filter[2], &state->Chans[0].filter[2]); + BiquadFilter_copyParams(&state->Chans[i].filter[3], &state->Chans[0].filter[3]); + } + + STATIC_CAST(ALeffectState,state)->OutBuffer = device->FOAOut.Buffer; + STATIC_CAST(ALeffectState,state)->OutChannels = device->FOAOut.NumChannels; + for(i = 0;i < MAX_EFFECT_CHANNELS;i++) + ComputePanGains(&device->FOAOut, IdentityMatrixf.m[i], slot->Params.Gain, + state->Chans[i].TargetGains); +} + +static ALvoid ALequalizerState_process(ALequalizerState *state, ALsizei SamplesToDo, const ALfloat (*RESTRICT SamplesIn)[BUFFERSIZE], ALfloat (*RESTRICT SamplesOut)[BUFFERSIZE], ALsizei NumChannels) +{ + ALfloat (*RESTRICT temps)[BUFFERSIZE] = state->SampleBuffer; + ALsizei c; + + for(c = 0;c < MAX_EFFECT_CHANNELS;c++) + { + BiquadFilter_process(&state->Chans[c].filter[0], temps[0], SamplesIn[c], SamplesToDo); + BiquadFilter_process(&state->Chans[c].filter[1], temps[1], temps[0], SamplesToDo); + BiquadFilter_process(&state->Chans[c].filter[2], temps[2], temps[1], SamplesToDo); + BiquadFilter_process(&state->Chans[c].filter[3], temps[3], temps[2], SamplesToDo); + + MixSamples(temps[3], NumChannels, SamplesOut, + state->Chans[c].CurrentGains, state->Chans[c].TargetGains, + SamplesToDo, 0, SamplesToDo + ); + } +} + + +struct EqualizerStateFactory final : public EffectStateFactory { + EqualizerStateFactory() noexcept; +}; + +ALeffectState *EqualizerStateFactory_create(EqualizerStateFactory *UNUSED(factory)) +{ + ALequalizerState *state; + + NEW_OBJ0(state, ALequalizerState)(); + if(!state) return NULL; + + return STATIC_CAST(ALeffectState, state); +} + +DEFINE_EFFECTSTATEFACTORY_VTABLE(EqualizerStateFactory); + +EqualizerStateFactory::EqualizerStateFactory() noexcept + : EffectStateFactory{GET_VTABLE2(EqualizerStateFactory, EffectStateFactory)} +{ +} + +EffectStateFactory *EqualizerStateFactory_getFactory(void) +{ + static EqualizerStateFactory EqualizerFactory{}; + return STATIC_CAST(EffectStateFactory, &EqualizerFactory); +} + + +void ALequalizer_setParami(ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, ALint UNUSED(val)) +{ alSetError(context, AL_INVALID_ENUM, "Invalid equalizer integer property 0x%04x", param); } +void ALequalizer_setParamiv(ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, const ALint *UNUSED(vals)) +{ alSetError(context, AL_INVALID_ENUM, "Invalid equalizer integer-vector property 0x%04x", param); } +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)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer low-band gain out of range"); + props->Equalizer.LowGain = val; + break; + + case AL_EQUALIZER_LOW_CUTOFF: + if(!(val >= AL_EQUALIZER_MIN_LOW_CUTOFF && val <= AL_EQUALIZER_MAX_LOW_CUTOFF)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer low-band cutoff out of range"); + props->Equalizer.LowCutoff = val; + break; + + case AL_EQUALIZER_MID1_GAIN: + if(!(val >= AL_EQUALIZER_MIN_MID1_GAIN && val <= AL_EQUALIZER_MAX_MID1_GAIN)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer mid1-band gain out of range"); + props->Equalizer.Mid1Gain = val; + break; + + case AL_EQUALIZER_MID1_CENTER: + if(!(val >= AL_EQUALIZER_MIN_MID1_CENTER && val <= AL_EQUALIZER_MAX_MID1_CENTER)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer mid1-band center out of range"); + props->Equalizer.Mid1Center = val; + break; + + case AL_EQUALIZER_MID1_WIDTH: + if(!(val >= AL_EQUALIZER_MIN_MID1_WIDTH && val <= AL_EQUALIZER_MAX_MID1_WIDTH)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer mid1-band width out of range"); + props->Equalizer.Mid1Width = val; + break; + + case AL_EQUALIZER_MID2_GAIN: + if(!(val >= AL_EQUALIZER_MIN_MID2_GAIN && val <= AL_EQUALIZER_MAX_MID2_GAIN)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer mid2-band gain out of range"); + props->Equalizer.Mid2Gain = val; + break; + + case AL_EQUALIZER_MID2_CENTER: + if(!(val >= AL_EQUALIZER_MIN_MID2_CENTER && val <= AL_EQUALIZER_MAX_MID2_CENTER)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer mid2-band center out of range"); + props->Equalizer.Mid2Center = val; + break; + + case AL_EQUALIZER_MID2_WIDTH: + if(!(val >= AL_EQUALIZER_MIN_MID2_WIDTH && val <= AL_EQUALIZER_MAX_MID2_WIDTH)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer mid2-band width out of range"); + props->Equalizer.Mid2Width = val; + break; + + case AL_EQUALIZER_HIGH_GAIN: + if(!(val >= AL_EQUALIZER_MIN_HIGH_GAIN && val <= AL_EQUALIZER_MAX_HIGH_GAIN)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer high-band gain out of range"); + props->Equalizer.HighGain = val; + break; + + case AL_EQUALIZER_HIGH_CUTOFF: + if(!(val >= AL_EQUALIZER_MIN_HIGH_CUTOFF && val <= AL_EQUALIZER_MAX_HIGH_CUTOFF)) + SETERR_RETURN(context, AL_INVALID_VALUE,, "Equalizer high-band cutoff out of range"); + props->Equalizer.HighCutoff = val; + break; + + default: + alSetError(context, AL_INVALID_ENUM, "Invalid equalizer float property 0x%04x", param); + } +} +void ALequalizer_setParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals) +{ ALequalizer_setParamf(effect, context, param, vals[0]); } + +void ALequalizer_getParami(const ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, ALint *UNUSED(val)) +{ alSetError(context, AL_INVALID_ENUM, "Invalid equalizer integer property 0x%04x", param); } +void ALequalizer_getParamiv(const ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, ALint *UNUSED(vals)) +{ alSetError(context, AL_INVALID_ENUM, "Invalid equalizer integer-vector property 0x%04x", param); } +void ALequalizer_getParamf(const 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: + alSetError(context, AL_INVALID_ENUM, "Invalid equalizer float property 0x%04x", param); + } +} +void ALequalizer_getParamfv(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals) +{ ALequalizer_getParamf(effect, context, param, vals); } + +DEFINE_ALEFFECT_VTABLE(ALequalizer); |