488 lines
11 KiB
C++
488 lines
11 KiB
C++
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/*
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* DSP.cpp
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* -----------
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* Purpose: Mixing code for various DSPs (EQ, Mega-Bass, ...)
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* Notes : Ugh... This should really be removed at some point.
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* Authors: Olivier Lapicque
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* OpenMPT Devs
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* The OpenMPT source code is released under the BSD license. Read LICENSE for more details.
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*/
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#include "stdafx.h"
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#include "DSP.h"
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#include "../soundbase/SampleTypes.h"
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#include <math.h>
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OPENMPT_NAMESPACE_BEGIN
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#ifndef NO_DSP
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// Bass Expansion
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#define DEFAULT_XBASS_RANGE 14 // (x+2)*20 Hz (320Hz)
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#define DEFAULT_XBASS_DEPTH 6 // 1+(3>>(x-4)) (+6dB)
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////////////////////////////////////////////////////////////////////
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// DSP Effects internal state
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static void X86_StereoDCRemoval(int *, uint32 count, int32 &nDCRFlt_Y1l, int32 &nDCRFlt_X1l, int32 &nDCRFlt_Y1r, int32 &nDCRFlt_X1r);
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static void X86_MonoDCRemoval(int *, uint32 count, int32 &nDCRFlt_Y1l, int32 &nDCRFlt_X1l);
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///////////////////////////////////////////////////////////////////////////////////
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//
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// Biquad setup
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//
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#define PI 3.14159265358979323f
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static inline float Sgn(float x) { return (x >= 0) ? 1.0f : -1.0f; }
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static void ShelfEQ(int32 scale,
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int32 &outA1, int32 &outB0, int32 &outB1,
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int32 F_c, int32 F_s, float gainDC, float gainFT, float gainPI)
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{
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float a1, b0, b1;
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float gainFT2, gainDC2, gainPI2;
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float alpha, beta0, beta1, rho;
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float wT, quad;
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wT = PI * F_c / F_s;
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gainPI2 = gainPI * gainPI;
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gainFT2 = gainFT * gainFT;
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gainDC2 = gainDC * gainDC;
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quad = gainPI2 + gainDC2 - (gainFT2*2);
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alpha = 0;
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if (quad != 0)
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{
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float lambda = (gainPI2 - gainDC2) / quad;
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alpha = (float)(lambda - Sgn(lambda)*sqrt(lambda*lambda - 1.0f));
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}
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beta0 = 0.5f * ((gainDC + gainPI) + (gainDC - gainPI) * alpha);
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beta1 = 0.5f * ((gainDC - gainPI) + (gainDC + gainPI) * alpha);
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rho = (float)((sin((wT*0.5f) - (PI/4.0f))) / (sin((wT*0.5f) + (PI/4.0f))));
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quad = 1.0f / (1.0f + rho*alpha);
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b0 = ((beta0 + rho*beta1) * quad);
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b1 = ((beta1 + rho*beta0) * quad);
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a1 = - ((rho + alpha) * quad);
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outA1 = mpt::saturate_round<int32>(a1 * scale);
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outB0 = mpt::saturate_round<int32>(b0 * scale);
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outB1 = mpt::saturate_round<int32>(b1 * scale);
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}
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CSurroundSettings::CSurroundSettings() : m_nProLogicDepth(12), m_nProLogicDelay(20)
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{
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}
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CMegaBassSettings::CMegaBassSettings() : m_nXBassDepth(DEFAULT_XBASS_DEPTH), m_nXBassRange(DEFAULT_XBASS_RANGE)
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{
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}
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CSurround::CSurround()
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{
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// Surround Encoding: 1 delay line + low-pass filter + high-pass filter
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nSurroundSize = 0;
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nSurroundPos = 0;
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nDolbyDepth = 0;
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// Surround Biquads
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nDolbyHP_Y1 = 0;
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nDolbyHP_X1 = 0;
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nDolbyLP_Y1 = 0;
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nDolbyHP_B0 = 0;
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nDolbyHP_B1 = 0;
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nDolbyHP_A1 = 0;
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nDolbyLP_B0 = 0;
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nDolbyLP_B1 = 0;
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nDolbyLP_A1 = 0;
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MemsetZero(SurroundBuffer);
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}
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CMegaBass::CMegaBass()
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{
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// Bass Expansion: low-pass filter
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nXBassFlt_Y1 = 0;
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nXBassFlt_X1 = 0;
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nXBassFlt_B0 = 0;
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nXBassFlt_B1 = 0;
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nXBassFlt_A1 = 0;
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// DC Removal Biquad
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nDCRFlt_Y1lf = 0;
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nDCRFlt_X1lf = 0;
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nDCRFlt_Y1rf = 0;
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nDCRFlt_X1rf = 0;
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nDCRFlt_Y1lb = 0;
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nDCRFlt_X1lb = 0;
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nDCRFlt_Y1rb = 0;
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nDCRFlt_X1rb = 0;
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}
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void CSurround::Initialize(bool bReset, DWORD MixingFreq)
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{
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MPT_UNREFERENCED_PARAMETER(bReset);
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if (!m_Settings.m_nProLogicDelay) m_Settings.m_nProLogicDelay = 20;
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// Pro-Logic Surround
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nSurroundPos = nSurroundSize = 0;
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{
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memset(SurroundBuffer, 0, sizeof(SurroundBuffer));
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nSurroundSize = (MixingFreq * m_Settings.m_nProLogicDelay) / 1000;
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if (nSurroundSize > SURROUNDBUFFERSIZE) nSurroundSize = SURROUNDBUFFERSIZE;
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nDolbyDepth = m_Settings.m_nProLogicDepth;
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if (nDolbyDepth < 1) nDolbyDepth = 1;
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if (nDolbyDepth > 16) nDolbyDepth = 16;
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// Setup biquad filters
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ShelfEQ(1024, nDolbyHP_A1, nDolbyHP_B0, nDolbyHP_B1, 200, MixingFreq, 0, 0.5f, 1);
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ShelfEQ(1024, nDolbyLP_A1, nDolbyLP_B0, nDolbyLP_B1, 7000, MixingFreq, 1, 0.75f, 0);
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nDolbyHP_X1 = nDolbyHP_Y1 = 0;
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nDolbyLP_Y1 = 0;
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// Surround Level
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nDolbyHP_B0 = (nDolbyHP_B0 * nDolbyDepth) >> 5;
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nDolbyHP_B1 = (nDolbyHP_B1 * nDolbyDepth) >> 5;
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// +6dB
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nDolbyLP_B0 *= 2;
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nDolbyLP_B1 *= 2;
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}
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}
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void CMegaBass::Initialize(bool bReset, DWORD MixingFreq)
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{
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// Bass Expansion Reset
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{
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int32 a1 = 0, b0 = 1024, b1 = 0;
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int nXBassCutOff = 50 + (m_Settings.m_nXBassRange+2) * 20;
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int nXBassGain = m_Settings.m_nXBassDepth;
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nXBassGain = std::clamp(nXBassGain, 2, 8);
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nXBassCutOff = std::clamp(nXBassCutOff, 60, 600);
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ShelfEQ(1024, a1, b0, b1, nXBassCutOff, MixingFreq,
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1.0f + (1.0f/16.0f) * (0x300 >> nXBassGain),
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1.0f,
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0.0000001f);
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if (nXBassGain > 5)
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{
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b0 >>= (nXBassGain-5);
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b1 >>= (nXBassGain-5);
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}
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nXBassFlt_A1 = a1;
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nXBassFlt_B0 = b0;
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nXBassFlt_B1 = b1;
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//Log("b0=%d b1=%d a1=%d\n", b0, b1, a1);
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}
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if (bReset)
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{
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nXBassFlt_X1 = 0;
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nXBassFlt_Y1 = 0;
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nDCRFlt_X1lf = 0;
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nDCRFlt_X1rf = 0;
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nDCRFlt_Y1lf = 0;
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nDCRFlt_Y1rf = 0;
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nDCRFlt_X1lb = 0;
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nDCRFlt_X1rb = 0;
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nDCRFlt_Y1lb = 0;
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nDCRFlt_Y1rb = 0;
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}
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}
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// 2-channel surround
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void CSurround::ProcessStereoSurround(int * MixSoundBuffer, int count)
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{
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int *pr = MixSoundBuffer, hy1 = nDolbyHP_Y1;
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for (int r=count; r; r--)
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{
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// Delay
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int secho = SurroundBuffer[nSurroundPos];
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SurroundBuffer[nSurroundPos] = (pr[0]+pr[1]+256) >> 9;
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// High-pass
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int v0 = (nDolbyHP_B0 * secho + nDolbyHP_B1 * nDolbyHP_X1 + nDolbyHP_A1 * hy1) >> 10;
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nDolbyHP_X1 = secho;
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// Low-pass
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int v = (nDolbyLP_B0 * v0 + nDolbyLP_B1 * hy1 + nDolbyLP_A1 * nDolbyLP_Y1) >> (10-8);
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hy1 = v0;
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nDolbyLP_Y1 = v >> 8;
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// Add echo
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pr[0] += v;
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pr[1] -= v;
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if (++nSurroundPos >= nSurroundSize) nSurroundPos = 0;
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pr += 2;
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}
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nDolbyHP_Y1 = hy1;
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}
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// 4-channels surround
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void CSurround::ProcessQuadSurround(int * MixSoundBuffer, int * MixRearBuffer, int count)
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{
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int *pr = MixSoundBuffer, hy1 = nDolbyHP_Y1;
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for (int r=count; r; r--)
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{
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int vl = pr[0] >> 1;
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int vr = pr[1] >> 1;
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pr[(uint32)(MixRearBuffer-MixSoundBuffer)] += vl;
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pr[((uint32)(MixRearBuffer-MixSoundBuffer))+1] += vr;
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// Delay
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int secho = SurroundBuffer[nSurroundPos];
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SurroundBuffer[nSurroundPos] = (vr+vl+256) >> 9;
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// High-pass
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int v0 = (nDolbyHP_B0 * secho + nDolbyHP_B1 * nDolbyHP_X1 + nDolbyHP_A1 * hy1) >> 10;
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nDolbyHP_X1 = secho;
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// Low-pass
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int v = (nDolbyLP_B0 * v0 + nDolbyLP_B1 * hy1 + nDolbyLP_A1 * nDolbyLP_Y1) >> (10-8);
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hy1 = v0;
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nDolbyLP_Y1 = v >> 8;
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// Add echo
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pr[(uint32)(MixRearBuffer-MixSoundBuffer)] += v;
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pr[((uint32)(MixRearBuffer-MixSoundBuffer))+1] += v;
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if (++nSurroundPos >= nSurroundSize) nSurroundPos = 0;
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pr += 2;
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}
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nDolbyHP_Y1 = hy1;
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}
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void CSurround::Process(int * MixSoundBuffer, int * MixRearBuffer, int count, uint32 nChannels)
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{
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if(nChannels >= 2)
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// Dolby Pro-Logic Surround
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{
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if (nChannels > 2) ProcessQuadSurround(MixSoundBuffer, MixRearBuffer, count); else
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ProcessStereoSurround(MixSoundBuffer, count);
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}
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}
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void CMegaBass::Process(int * MixSoundBuffer, int * MixRearBuffer, int count, uint32 nChannels)
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{
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if(nChannels >= 2)
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{
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X86_StereoDCRemoval(MixSoundBuffer, count, nDCRFlt_Y1lf, nDCRFlt_X1lf, nDCRFlt_Y1rf, nDCRFlt_X1rf);
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if(nChannels > 2) X86_StereoDCRemoval(MixRearBuffer, count, nDCRFlt_Y1lb, nDCRFlt_X1lb, nDCRFlt_Y1rb, nDCRFlt_X1rb);
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int *px = MixSoundBuffer;
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int *py = MixRearBuffer;
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int x1 = nXBassFlt_X1;
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int y1 = nXBassFlt_Y1;
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if(nChannels > 2) for (int x=count; x; x--)
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{
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int x_m = (px[0]+px[1]+py[0]+py[1]+0x100)>>9;
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y1 = (nXBassFlt_B0 * x_m + nXBassFlt_B1 * x1 + nXBassFlt_A1 * y1) >> (10-8);
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x1 = x_m;
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px[0] += y1;
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px[1] += y1;
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py[0] += y1;
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py[1] += y1;
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y1 = (y1+0x80) >> 8;
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px += 2;
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py += 2;
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} else for (int x=count; x; x--)
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{
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int x_m = (px[0]+px[1]+0x100)>>9;
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y1 = (nXBassFlt_B0 * x_m + nXBassFlt_B1 * x1 + nXBassFlt_A1 * y1) >> (10-8);
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x1 = x_m;
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px[0] += y1;
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px[1] += y1;
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y1 = (y1+0x80) >> 8;
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px += 2;
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}
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nXBassFlt_X1 = x1;
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nXBassFlt_Y1 = y1;
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} else
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{
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X86_MonoDCRemoval(MixSoundBuffer, count, nDCRFlt_Y1lf, nDCRFlt_X1lf);
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int *px = MixSoundBuffer;
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int x1 = nXBassFlt_X1;
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int y1 = nXBassFlt_Y1;
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for (int x=count; x; x--)
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{
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int x_m = (px[0]+0x80)>>8;
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y1 = (nXBassFlt_B0 * x_m + nXBassFlt_B1 * x1 + nXBassFlt_A1 * y1) >> (10-8);
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x1 = x_m;
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px[0] += y1;
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y1 = (y1+0x40) >> 8;
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px++;
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}
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nXBassFlt_X1 = x1;
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nXBassFlt_Y1 = y1;
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}
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}
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//////////////////////////////////////////////////////////////////////////
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//
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// DC Removal
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//
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#define DCR_AMOUNT 9
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static void X86_StereoDCRemoval(int *pBuffer, uint32 nSamples, int32 &nDCRFlt_Y1l, int32 &nDCRFlt_X1l, int32 &nDCRFlt_Y1r, int32 &nDCRFlt_X1r)
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{
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int y1l = nDCRFlt_Y1l, x1l = nDCRFlt_X1l;
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int y1r = nDCRFlt_Y1r, x1r = nDCRFlt_X1r;
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while(nSamples--)
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{
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int inL = pBuffer[0];
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int inR = pBuffer[1];
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int diffL = x1l - inL;
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int diffR = x1r - inR;
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x1l = inL;
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x1r = inR;
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int outL = diffL / (1 << (DCR_AMOUNT + 1)) - diffL + y1l;
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int outR = diffR / (1 << (DCR_AMOUNT + 1)) - diffR + y1r;
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pBuffer[0] = outL;
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pBuffer[1] = outR;
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pBuffer += 2;
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y1l = outL - outL / (1 << DCR_AMOUNT);
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y1r = outR - outR / (1 << DCR_AMOUNT);
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}
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nDCRFlt_Y1l = y1l;
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nDCRFlt_X1l = x1l;
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nDCRFlt_Y1r = y1r;
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nDCRFlt_X1r = x1r;
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}
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static void X86_MonoDCRemoval(int *pBuffer, uint32 nSamples, int32 &nDCRFlt_Y1l, int32 &nDCRFlt_X1l)
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{
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int y1l = nDCRFlt_Y1l, x1l = nDCRFlt_X1l;
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while(nSamples--)
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{
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int inM = pBuffer[0];
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int diff = x1l - inM;
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x1l = inM;
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pBuffer[0] = inM = diff / (1 << (DCR_AMOUNT + 1)) - diff + y1l;
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pBuffer++;
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y1l = inM - inM / (1 << DCR_AMOUNT);
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}
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nDCRFlt_Y1l = y1l;
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nDCRFlt_X1l = x1l;
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}
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/////////////////////////////////////////////////////////////////
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// Clean DSP Effects interface
|
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// [XBass level 0(quiet)-100(loud)], [cutoff in Hz 20-100]
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void CMegaBass::SetXBassParameters(uint32 nDepth, uint32 nRange)
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{
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if (nDepth > 100) nDepth = 100;
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uint32 gain = nDepth / 20;
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if (gain > 4) gain = 4;
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m_Settings.m_nXBassDepth = 8 - gain; // filter attenuation 1/256 .. 1/16
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uint32 range = nRange / 5;
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if (range > 5) range -= 5; else range = 0;
|
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if (nRange > 16) nRange = 16;
|
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m_Settings.m_nXBassRange = 21 - range; // filter average on 0.5-1.6ms
|
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}
|
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|
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// [Surround level 0(quiet)-100(heavy)] [delay in ms, usually 5-50ms]
|
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void CSurround::SetSurroundParameters(uint32 nDepth, uint32 nDelay)
|
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{
|
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uint32 gain = (nDepth * 16) / 100;
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if (gain > 16) gain = 16;
|
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if (gain < 1) gain = 1;
|
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m_Settings.m_nProLogicDepth = gain;
|
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if (nDelay < 4) nDelay = 4;
|
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if (nDelay > 50) nDelay = 50;
|
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m_Settings.m_nProLogicDelay = nDelay;
|
||
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}
|
||
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|
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BitCrushSettings::BitCrushSettings()
|
||
|
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: m_Bits(8)
|
||
|
|
{
|
||
|
|
return;
|
||
|
|
}
|
||
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|
||
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|
||
|
|
BitCrush::BitCrush()
|
||
|
|
{
|
||
|
|
}
|
||
|
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|
||
|
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|
||
|
|
void BitCrush::Initialize(bool bReset, DWORD MixingFreq)
|
||
|
|
{
|
||
|
|
MPT_UNREFERENCED_PARAMETER(bReset);
|
||
|
|
MPT_UNREFERENCED_PARAMETER(MixingFreq);
|
||
|
|
}
|
||
|
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|
||
|
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|
||
|
|
void BitCrush::Process(int * MixSoundBuffer, int * MixRearBuffer, int count, uint32 nChannels)
|
||
|
|
{
|
||
|
|
if(m_Settings.m_Bits <= 0)
|
||
|
|
{
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
if(m_Settings.m_Bits > MixSampleIntTraits::mix_precision_bits())
|
||
|
|
{
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
unsigned int mask = ~((1u << (MixSampleIntTraits::mix_precision_bits() - m_Settings.m_Bits)) - 1u);
|
||
|
|
if(nChannels == 4)
|
||
|
|
{
|
||
|
|
for(int frame = 0; frame < count; ++frame)
|
||
|
|
{
|
||
|
|
MixSoundBuffer[frame*2 + 0] &= mask;
|
||
|
|
MixSoundBuffer[frame*2 + 1] &= mask;
|
||
|
|
MixRearBuffer[frame*2 + 0] &= mask;
|
||
|
|
MixRearBuffer[frame*2 + 1] &= mask;
|
||
|
|
}
|
||
|
|
} else if(nChannels == 2)
|
||
|
|
{
|
||
|
|
for(int frame = 0; frame < count; ++frame)
|
||
|
|
{
|
||
|
|
MixSoundBuffer[frame*2 + 0] &= mask;
|
||
|
|
MixSoundBuffer[frame*2 + 1] &= mask;
|
||
|
|
}
|
||
|
|
} else if(nChannels == 1)
|
||
|
|
{
|
||
|
|
for(int frame = 0; frame < count; ++frame)
|
||
|
|
{
|
||
|
|
MixSoundBuffer[frame] &= mask;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
#else
|
||
|
|
|
||
|
|
|
||
|
|
MPT_MSVC_WORKAROUND_LNK4221(DSP)
|
||
|
|
|
||
|
|
|
||
|
|
#endif // NO_DSP
|
||
|
|
|
||
|
|
|
||
|
|
OPENMPT_NAMESPACE_END
|