diff options
| -rw-r--r-- | Alc/effects/compressor.c | 88 |
1 files changed, 51 insertions, 37 deletions
diff --git a/Alc/effects/compressor.c b/Alc/effects/compressor.c index 8c639f43..2131104c 100644 --- a/Alc/effects/compressor.c +++ b/Alc/effects/compressor.c @@ -35,10 +35,9 @@ typedef struct ALcompressorState { /* Effect parameters */ ALboolean Enabled; - ALfloat Envelope; - ALfloat EnvGain; - ALfloat Attack; - ALfloat Release; + ALfloat AttackRate; + ALfloat ReleaseRate; + ALfloat GainCtrl; } ALcompressorState; static ALvoid ALcompressorState_Destruct(ALcompressorState *UNUSED(state)) @@ -47,10 +46,11 @@ static ALvoid ALcompressorState_Destruct(ALcompressorState *UNUSED(state)) static ALboolean ALcompressorState_deviceUpdate(ALcompressorState *state, ALCdevice *device) { - state->Attack = expf(-1.0f / (device->Frequency * 0.0001f)); - state->Release = expf(-1.0f / (device->Frequency * 0.3f)); - state->Envelope = 0.0f; - state->EnvGain = 1.0f; + const ALfloat attackTime = device->Frequency * 0.2f; /* 200ms Attack */ + const ALfloat releaseTime = device->Frequency * 0.4f; /* 400ms Release */ + + state->AttackRate = 1.0 / attackTime; + state->ReleaseRate = 1.0 / releaseTime; return AL_TRUE; } @@ -60,9 +60,6 @@ static ALvoid ALcompressorState_update(ALcompressorState *state, ALCdevice *Devi ALfloat gain; state->Enabled = Slot->EffectProps.Compressor.OnOff; - /* FIXME: Could maybe use the compressor's attack/release to move the gain to 1? */ - if(!state->Enabled) - state->EnvGain = 1.0f; gain = sqrtf(1.0f / Device->NumChan) * Slot->Gain; SetGains(Device, gain, state->Gain); @@ -70,46 +67,61 @@ static ALvoid ALcompressorState_update(ALcompressorState *state, ALCdevice *Devi static ALvoid ALcompressorState_process(ALcompressorState *state, ALuint SamplesToDo, const ALfloat *SamplesIn, ALfloat (*SamplesOut)[BUFFERSIZE]) { - ALfloat env = state->Envelope; - ALfloat envgain = state->EnvGain; - ALfloat tattack = state->Attack; - ALfloat trelease = state->Release; ALuint it, kt; ALuint base; - ALfloat theta; - ALfloat rms; for(base = 0;base < SamplesToDo;) { ALfloat temps[64]; ALuint td = minu(SamplesToDo-base, 64); - ALfloat summ = 0.0f; - for(it = 0;it < td;it++) + if(state->Enabled) { - ALfloat smp = SamplesIn[it+base] * 0.5f; - summ += smp * smp; - temps[it] = smp; - } + ALfloat output, smp, amplitude; + ALfloat gain = state->GainCtrl; - if(state->Enabled) + 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 { - const ALfloat threshold = 0.5f; - const ALfloat slope = 0.5f; + 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); - /* computing rms and envelope */ - rms = sqrtf(summ / td); - theta = ((rms > env) ? tattack : trelease); - env = (1.0f - theta)*rms + theta*env; + temps[it] = smp * output; + } - /* applying a hard-knee rms based compressor */ - if(env > threshold) - envgain = envgain - (env - threshold) * slope; + state->GainCtrl = gain; } + for(kt = 0;kt < MaxChannels;kt++) { - ALfloat gain = state->Gain[kt] * envgain * 2.0f; + ALfloat gain = state->Gain[kt]; if(!(gain > GAIN_SILENCE_THRESHOLD)) continue; @@ -119,9 +131,6 @@ static ALvoid ALcompressorState_process(ALcompressorState *state, ALuint Samples base += td; } - - state->Envelope = env; - state->EnvGain = envgain; } static void ALcompressorState_Delete(ALcompressorState *state) @@ -144,6 +153,11 @@ static ALeffectState *ALcompressorStateFactory_create(ALcompressorStateFactory * 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); } |