Update

CMakeLists.txt

@@ -4,21 +4,18 @@ set(CMAKE_CXX_COMPILER_VERSION 20)
 # NDK Settings
 #set(ANDROID_ABI arm64-v8a)
 set(ANDROID_ABI armeabi-v7a)
-#set(ANDROID_ARM_NEON true)
+set(ANDROID_ARM_NEON true)
 set(ANDROID_PLATFORM android-21)
-SET(CMAKE_CXX_FLAGS "-O0")
-SET(CMAKE_C_FLAGS "-O0")
 
-project("ViPER4Android Reworked")
+project("ViPER4Android")
-add_compile_definitions(VERSION_MAJOR=1)
+add_compile_definitions(VERSION_CODE=1)
-add_compile_definitions(VERSION_MINOR=0)
+add_compile_definitions(VERSION_NAME="1.0.0")
-add_compile_definitions(VERSION_CODENAME="Reworked")
 
-# KISS FFT
+## KISS FFT
-set(KISSFFT_PKGCONFIG OFF)
+#set(KISSFFT_PKGCONFIG OFF)
-set(KISSFFT_STATIC ON)
+#set(KISSFFT_STATIC ON)
-set(KISSFFT_TEST OFF)
+#set(KISSFFT_TEST OFF)
-set(KISSFFT_TOOLS OFF)
+#set(KISSFFT_TOOLS OFF)
 #add_subdirectory(src/cpp/viper/kissfft)
 
 # ViPERFX

src/ViPER4Android.cpp

@@ -159,13 +159,6 @@ static int32_t handleGetParam(ViperContext *pContext, effect_param_t *pCmdParam,
     memcpy(pReplyParam, pCmdParam, sizeof(effect_param_t) + pCmdParam->psize);
 
     switch (*(uint32_t *) pCmdParam->data) {
-        case PARAM_GET_DRIVER_VERSION: {
-            pReplyParam->status = 0;
-            pReplyParam->vsize = sizeof(uint32_t);
-            *(uint32_t *) (pReplyParam->data + vOffset) = 0x2050005; // As original, change as needed
-            *pReplySize = sizeof(effect_param_t) + pReplyParam->psize + vOffset + pReplyParam->vsize;
-            return 0;
-        }
         case PARAM_GET_ENABLED: {
             pReplyParam->status = 0;
             pReplyParam->vsize = sizeof(int32_t);
@@ -214,6 +207,20 @@ static int32_t handleGetParam(ViperContext *pContext, effect_param_t *pCmdParam,
             *pReplySize = sizeof(effect_param_t) + pReplyParam->psize + vOffset + pReplyParam->vsize;
             return 0;
         }
+        case PARAM_GET_DRIVER_VERSION_CODE: {
+            pReplyParam->status = 0;
+            pReplyParam->vsize = sizeof(uint32_t);
+            *(int32_t *) (pReplyParam->data + vOffset) = VERSION_CODE;
+            *pReplySize = sizeof(effect_param_t) + pReplyParam->psize + vOffset + pReplyParam->vsize;
+            return 0;
+        }
+        case PARAM_GET_DRIVER_VERSION_NAME: {
+            pReplyParam->status = 0;
+            pReplyParam->vsize = strlen(VERSION_NAME);
+            memcpy(pReplyParam->data + vOffset, VERSION_NAME, pReplyParam->vsize);
+            *pReplySize = sizeof(effect_param_t) + pReplyParam->psize + vOffset + pReplyParam->vsize;
+            return 0;
+        }
     }
     return 0;
 }
@@ -272,9 +279,7 @@ static int32_t Viper_ICommand(effect_handle_t self,
 static int32_t Viper_IGetDescriptor(effect_handle_t self, effect_descriptor_t *pDescriptor) {
     auto pContext = reinterpret_cast<ViperContext *>(self);
 
-    if (pContext == nullptr || pDescriptor == nullptr) {
+    if (pContext == nullptr || pDescriptor == nullptr) return -EINVAL;
-        return -EINVAL;
-    }
 
     *pDescriptor = viper_descriptor;
 

src/ViPER4Android.h

@@ -9,12 +9,13 @@ extern "C" {
 #define COMMAND_CODE_SET 0x02
 
 // Param get
-#define PARAM_GET_DRIVER_VERSION 0
 #define PARAM_GET_ENABLED 1
 #define PARAM_GET_CONFIGURE 2
 #define PARAM_GET_STREAMING 3
 #define PARAM_GET_SAMPLING_RATE 4
 #define PARAM_GET_CONVOLUTION_KERNEL_ID 5
+#define PARAM_GET_DRIVER_VERSION_CODE 6
+#define PARAM_GET_DRIVER_VERSION_NAME 7
 
 // Param set
 #define PARAM_SET_UPDATE_STATUS 0x9002

src/viper/ViPER.cpp

@@ -5,7 +5,7 @@
 
 ViPER::ViPER() {
     VIPER_LOGI("Welcome to ViPER FX");
-    VIPER_LOGI("Current version is %s %s", VERSION_STRING, VERSION_CODENAME);
+    VIPER_LOGI("Current version is %s (%d)", VERSION_NAME, VERSION_CODE);
 
     this->samplingRate = VIPER_DEFAULT_SAMPLING_RATE;
 

src/viper/constants.h

@@ -8,9 +8,5 @@
 
 #include "../log.h" // TODO: Remove this dependency
 
-#define STR_HELPER(x) #x
-#define STR(x) STR_HELPER(x)
-#define VERSION_STRING "v" STR(VERSION_MAJOR) "." STR(VERSION_MINOR)
-
 #define VIPER_DEFAULT_SAMPLING_RATE 44100
 #define VIPER_AUTHORS "viper.WYF, Martmists, Iscle"

src/viper/effects/Cure.cpp

@@ -1,5 +1,7 @@
 #include "Cure.h"
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 Cure::Cure() {
     this->enabled = false;
     Reset();
@@ -17,15 +19,16 @@ float Cure::GetLevelDelay() {
     return this->crossfeed.GetLevelDelay();
 }
 
+// TODO: Fix with crossfeed
 struct Crossfeed::Preset Cure::GetPreset() {
     return this->crossfeed.GetPreset();
 }
 
 void Cure::Process(float *buffer, uint32_t size) {
-    if (this->enabled) {
+    if (!this->enabled) return;
-        this->crossfeed.ProcessFrames(buffer, size);
+
-        this->passFilter.ProcessFrames(buffer, size);
+    this->crossfeed.ProcessFrames(buffer, size);
-    }
+    this->passFilter.ProcessFrames(buffer, size);
 }
 
 void Cure::Reset() {
@@ -39,10 +42,10 @@ void Cure::SetCutoff(uint16_t cutoff) {
 
 void Cure::SetEnable(bool enabled) {
     if (this->enabled != enabled) {
-        this->enabled = enabled;
         if (enabled) {
             Reset();
         }
+        this->enabled = enabled;
     }
 }
 

src/viper/effects/Cure.h

@@ -4,6 +4,8 @@
 #include "../utils/Crossfeed.h"
 #include "../utils/PassFilter.h"
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 class Cure {
 public:
     Cure();
@@ -11,7 +13,7 @@ public:
     uint16_t GetCutoff();
     float GetFeedback();
     float GetLevelDelay();
-    struct Crossfeed::Preset GetPreset();
+    struct Crossfeed::Preset GetPreset(); // TODO: Fix with crossfeed
     void Process(float *buffer, uint32_t size);
     void Reset();
     void SetCutoff(uint16_t cutoff);

src/viper/effects/IIRFilter.cpp

@@ -3,7 +3,7 @@
 #include "IIRFilter.h"
 #include "../constants.h"
 
-// Iscle: Verified with latest version at 13/12/2022
+// Iscle: Verified with the latest version at 13/12/2022
 
 IIRFilter::IIRFilter(uint32_t bands) {
     this->enable = false;
@@ -75,10 +75,10 @@ void IIRFilter::SetBandLevel(uint32_t band, float level) {
 
 void IIRFilter::SetEnable(bool enable) {
     if (this->enable != enable) {
-        this->enable = enable;
         if (enable) {
             Reset();
         }
+        this->enable = enable;
     }
 }
 

src/viper/effects/IIRFilter.h

@@ -3,7 +3,7 @@
 #include <cstdint>
 #include "../utils/MinPhaseIIRCoeffs.h"
 
-// Iscle: Verified with latest version at 13/12/2022
+// Iscle: Verified with the latest version at 13/12/2022
 
 class IIRFilter {
 public:

src/viper/effects/SpeakerCorrection.cpp

@@ -1,6 +1,8 @@
 #include "SpeakerCorrection.h"
 #include "../constants.h"
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 SpeakerCorrection::SpeakerCorrection() {
     this->samplingRate = VIPER_DEFAULT_SAMPLING_RATE;
     this->enable = false;
@@ -43,7 +45,7 @@ void SpeakerCorrection::Reset() {
 
 void SpeakerCorrection::SetEnable(bool enable) {
     if (this->enable != enable) {
-        if (!this->enable) {
+        if (enable) {
             Reset();
         }
         this->enable = enable;

src/viper/effects/SpeakerCorrection.h

@@ -4,6 +4,8 @@
 #include "../utils/MultiBiquad.h"
 #include "../utils/Biquad.h"
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 class SpeakerCorrection {
 public:
     SpeakerCorrection();

src/viper/effects/TubeSimulator.cpp

@@ -1,14 +1,16 @@
 #include "TubeSimulator.h"
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 TubeSimulator::TubeSimulator() {
-    this->acc[0] = 0.f;
+    this->acc[0] = 0.0;
-    this->acc[1] = 0.f;
+    this->acc[1] = 0.0;
     this->enable = false;
 }
 
 void TubeSimulator::Reset() {
-    this->acc[0] = 0.f;
+    this->acc[0] = 0.0;
-    this->acc[1] = 0.f;
+    this->acc[1] = 0.0;
     this->enable = false;
 }
 
@@ -22,16 +24,12 @@ void TubeSimulator::SetEnable(bool enable) {
 }
 
 void TubeSimulator::TubeProcess(float *buffer, uint32_t size) {
-    if (this->enable) {
+    if (!this->enable) return;
-        for (uint32_t x = 0; x < size; x++) {
+
-            this->acc[0] = (this->acc[0] + buffer[2 * x]) / 2.f;
+    for (uint32_t i = 0; i < size; i += 2) {
-            this->acc[1] = (this->acc[1] + buffer[2 * x + 1]) / 2.f;
+        this->acc[0] = (this->acc[0] + buffer[i * 2]) / 2.0;
-            buffer[2 * x] = this->acc[0];
+        this->acc[1] = (this->acc[1] + buffer[i * 2 + 1]) / 2.0;
-            buffer[2 * x + 1] = this->acc[1];
+        buffer[i * 2] = (float) this->acc[0];
-        }
+        buffer[i * 2 + 1] = (float) this->acc[1];
     }
 }
-
-TubeSimulator::~TubeSimulator() {
-
-}

src/viper/effects/TubeSimulator.h

@@ -2,17 +2,18 @@
 
 #include <cstdint>
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 class TubeSimulator {
 public:
     TubeSimulator();
-    ~TubeSimulator();
 
     void Reset();
     void SetEnable(bool enable);
     void TubeProcess(float *buffer, uint32_t size);
 
 private:
-    float acc[2];
+    double acc[2];
     bool enable;
 };
 

src/viper/effects/ViPERBass.cpp

@@ -1,23 +1,25 @@
 #include "ViPERBass.h"
 #include "../constants.h"
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 ViPERBass::ViPERBass() {
-    this->enable = false;
-    this->samplingRate = VIPER_DEFAULT_SAMPLING_RATE;
     this->speaker = 60;
-    this->samplingRatePeriod = 1.0 / VIPER_DEFAULT_SAMPLING_RATE;
+    this->enable = false;
-    this->antiPop = 0.0;
     this->processMode = ProcessMode::NATURAL_BASS;
+    this->antiPop = 0.0;
     this->bassFactor = 0.0;
+    this->samplingRate = VIPER_DEFAULT_SAMPLING_RATE;
+    this->samplingRatePeriod = 1.0 / VIPER_DEFAULT_SAMPLING_RATE;
     this->polyphase = new Polyphase(2);
     this->biquad = new Biquad();
     this->subwoofer = new Subwoofer();
-    this->waveBuffer = new WaveBuffer(1, 0x1000);
+    this->waveBuffer = new WaveBuffer(1, 4096);
 
     this->biquad->Reset();
     this->biquad->SetLowPassParameter((float) this->speaker, this->samplingRate, 0.53);
     this->subwoofer->SetBassGain(this->samplingRate, 0.0);
-    this->Reset();
+    Reset();
 }
 
 ViPERBass::~ViPERBass() {
@@ -28,23 +30,17 @@ ViPERBass::~ViPERBass() {
 }
 
 void ViPERBass::Process(float *samples, uint32_t size) {
-    if (!this->enable) {
+    if (!this->enable) return;
-        return;
+    if (size == 0) return;
-    }
-
-    if (size == 0) {
-        return;
-    }
 
+    // Iscle: TODO: Maybe we could attenuate the effect instead of the entire sample
     if (this->antiPop < 1.0) {
         for (uint32_t i = 0; i < size * 2; i += 2) {
             samples[i] *= this->antiPop;
             samples[i + 1] *= this->antiPop;
             
             float x = this->antiPop + this->samplingRatePeriod;
-            if (x > 1.0) {
+            if (x > 1.0) x = 1.0;
-                x = 1.0;
-            }
             this->antiPop = x;
         }
     }
@@ -108,9 +104,7 @@ void ViPERBass::SetBassFactor(float bassFactor) {
 
 void ViPERBass::SetEnable(bool enable) {
     if (this->enable != enable) {
-        if (!this->enable) {
+        if (enable) Reset();
-            Reset();
-        }
         this->enable = enable;
     }
 }
@@ -118,7 +112,7 @@ void ViPERBass::SetEnable(bool enable) {
 void ViPERBass::SetProcessMode(ProcessMode processMode) {
     if (this->processMode != processMode) {
         this->processMode = processMode;
-        this->Reset();
+        Reset();
     }
 }
 

src/viper/effects/ViPERBass.h

@@ -6,6 +6,8 @@
 #include "../utils/WaveBuffer.h"
 #include "../utils/Polyphase.h"
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 class ViPERBass {
 public:
     enum ProcessMode {

src/viper/effects/ViPERClarity.cpp

@@ -1,6 +1,8 @@
 #include "ViPERClarity.h"
 #include "../constants.h"
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 ViPERClarity::ViPERClarity() {
     for (auto &highShelf : this->highShelf) {
         highShelf.SetFrequency(12000.0);
@@ -10,15 +12,13 @@ ViPERClarity::ViPERClarity() {
 
     this->enable = false;
     this->processMode = ClarityMode::NATURAL;
-    this->samplingRate = VIPER_DEFAULT_SAMPLING_RATE;
     this->clarityGainPercent = 0.0;
+    this->samplingRate = VIPER_DEFAULT_SAMPLING_RATE;
     Reset();
 }
 
 void ViPERClarity::Process(float *samples, uint32_t size) {
-    if (!this->enable) {
+    if (!this->enable) return;
-        return;
-    }
 
     switch (this->processMode) {
         case ClarityMode::NATURAL: {
@@ -26,8 +26,9 @@ void ViPERClarity::Process(float *samples, uint32_t size) {
             break;
         }
         case ClarityMode::OZONE: {
-            for (uint32_t i = 0; i < size * 2; i++) {
+            for (uint32_t i = 0; i < size * 2; i += 2) {
-                samples[i] = (float) this->highShelf[i % 2].Process(samples[i]);
+                samples[i] = (float) this->highShelf[0].Process(samples[i]);
+                samples[i + 1] = (float) this->highShelf[1].Process(samples[i + 1]);
             }
             break;
         }
@@ -41,7 +42,7 @@ void ViPERClarity::Process(float *samples, uint32_t size) {
 void ViPERClarity::Reset() {
     this->noiseSharpening.SetSamplingRate(this->samplingRate);
     this->noiseSharpening.Reset();
-    this->SetClarityToFilter();
+    SetClarityToFilter();
     for (auto &highShelf : this->highShelf) {
         highShelf.SetFrequency(8250.0);
         highShelf.SetSamplingRate(this->samplingRate);
@@ -52,10 +53,10 @@ void ViPERClarity::Reset() {
 
 void ViPERClarity::SetClarity(float gainPercent) {
     this->clarityGainPercent = gainPercent;
-    if (this->processMode != ClarityMode::OZONE) {
+    if (this->processMode == ClarityMode::OZONE) {
-        this->SetClarityToFilter();
-    } else {
         Reset();
+    } else {
+        SetClarityToFilter();
     }
 }
 
@@ -68,7 +69,7 @@ void ViPERClarity::SetClarityToFilter() {
 
 void ViPERClarity::SetEnable(bool enable) {
     if (this->enable != enable) {
-        if (!this->enable) {
+        if (enable) {
             Reset();
         }
         this->enable = enable;

src/viper/effects/ViPERClarity.h

@@ -5,6 +5,8 @@
 #include "../utils/HiFi.h"
 #include "../utils/HighShelf.h"
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 class ViPERClarity {
 public:
     enum ClarityMode {

src/viper/utils/Biquad.cpp

@@ -1,6 +1,7 @@
 #include "Biquad.h"
 #include <cmath>
 
+// Iscle: Verified with the latest version at 13/12/2022
 // Some variable names RE'd with help from https://github.com/wooters/miniDSP/blob/master/biquad.c
 
 Biquad::Biquad() {
@@ -41,14 +42,14 @@ void Biquad::SetBandPassParameter(float frequency, uint32_t samplingRate, float
     double sinOmega = sin(omega);
     double cosOmega = cos(omega);
 
-    double alpha = sinOmega / (2.0 * (double) qFactor);
+    double alpha = sinOmega / ((double) qFactor + (double) qFactor);
 
-    double a0 = 1.0 + alpha;
+    double a0 = alpha + 1.0;
-    double a1 = -2.0 * cosOmega;
+    double a1 = cosOmega * -2.0;
     double a2 = 1.0 - alpha;
     double b0 = sinOmega / 2.0; // Reference biquad implementation would use alpha here
     double b1 = 0.0;
-    double b2 = -sinOmega / 2.0; // Reference biquad implementation would use -alpha here
+    double b2 = -(sinOmega / 2.0); // Reference biquad implementation would use -alpha here
 
     SetCoeffs(a0, a1, a2, b0, b1, b2);
 }
@@ -59,37 +60,30 @@ void Biquad::SetCoeffs(double a0, double a1, double a2, double b0, double b1, do
     this->y2 = 0.0;
     this->y1 = 0.0;
 
-    this->a1 = -a1 / a0;
+    this->a1 = -(a1 / a0);
-    this->a2 = -a2 / a0;
+    this->a2 = -(a2 / a0);
     this->b0 = b0 / a0;
     this->b1 = b1 / a0;
     this->b2 = b2 / a0;
 }
 
-// TODO: Check
 void
 Biquad::SetHighPassParameter(float frequency, uint32_t samplingRate, double dbGain, float qFactor, double param_6) {
     double omega = (2.0 * M_PI * (double) frequency) / (double) samplingRate;
-    double sinX = sin(omega);
+    double sinOmega = sin(omega);
-    double cosX = cos(omega);
+    double cosOmega = cos(omega);
 
     double A = pow(10.0, dbGain / 40.0);
-    double sqrtY = sqrt(A);
+    double sqrtA = sqrt(A);
 
-    double z = sinX / 2.0 * sqrt((1.0 / A + A) * (1.0 / (double) qFactor - 1.0) + 2.0);
+    double z = sinOmega / 2.0 * sqrt((1.0 / A + A) * (1.0 / (double) qFactor - 1.0) + 2.0);
-    double a = (A - 1.0) * cosX;
-    double b = (A + 1.0) + a;
-    double c = (A + 1.0) * cosX;
-    double d = (A + 1.0) - a;
-    double e = pow(10.0, param_6 / 20.0);
-    double f = (A - 1.0) - c;
 
-    double a0 = d + (sqrtY * 2.0) * z;
+    double a0 = (A + 1.0) - (A - 1.0) * cosOmega + (sqrtA * 2.0) * z;
-    double a1 = f * 2.0;
+    double a1 = ((A - 1.0) - (A + 1.0) * cosOmega) * 2.0;
-    double a2 = d - (sqrtY * 2.0) * z;
+    double a2 = (A + 1.0) - (A - 1.0) * cosOmega - (sqrtA * 2.0) * z;
-    double b0 = (b + (sqrtY * 2.0) * z) * A * e;
+    double b0 = ((A + 1.0) + (A - 1.0) * cosOmega + (sqrtA * 2.0) * z) * A * omega;
-    double b1 = A * -2.0 * ((A - 1.0) + c) * e;
+    double b1 = A * -2.0 * ((A - 1.0) + (A + 1.0) * cosOmega) * omega;
-    double b2 = (b - (sqrtY * 2.0) * z) * A * e;
+    double b2 = ((A + 1.0) + (A - 1.0) * cosOmega - (sqrtA * 2.0) * z) * A * omega;
 
     SetCoeffs(a0, a1, a2, b0, b1, b2);
 }
@@ -99,10 +93,10 @@ void Biquad::SetLowPassParameter(float frequency, uint32_t samplingRate, float q
     double sinOmega = sin(omega);
     double cosOmega = cos(omega);
 
-    double alpha = sinOmega / (2.0 * (double) qFactor);
+    double alpha = sinOmega / ((double) qFactor + (double) qFactor);
 
-    double a0 = 1.0 + alpha;
+    double a0 = alpha + 1.0;
-    double a1 = -2.0 * cosOmega;
+    double a1 = cosOmega * -2.0;
     double a2 = 1.0 - alpha;
     double b0 = (1.0 - cosOmega) / 2.0;
     double b1 = 1.0 - cosOmega;

src/viper/utils/Biquad.h

@@ -2,6 +2,8 @@
 
 #include <cstdint>
 
+// Iscle: Verified with the latest version at 13/12/2022
+
 class Biquad {
 public:
     Biquad();

src/viper/utils/MinPhaseIIRCoeffs.cpp

@@ -2,7 +2,7 @@
 #include "../constants.h"
 #include <cmath>
 
-// Iscle: Verified with latest version at 13/12/2022
+// Iscle: Verified with the latest version at 13/12/2022
 
 static const float MIN_PHASE_IIR_COEFFS_FREQ_10BANDS[] = {
         31.0,

src/viper/utils/MinPhaseIIRCoeffs.h

@@ -2,7 +2,7 @@
 
 #include <cstdint>
 
-// Iscle: Verified with latest version at 13/12/2022
+// Iscle: Verified with the latest version at 13/12/2022
 
 class MinPhaseIIRCoeffs {
 public:

src/viper/utils/MultiBiquad.cpp

@@ -49,11 +49,11 @@ MultiBiquad::RefreshFilter(FilterType type, float gainAmp, float frequency, uint
     if (type == FilterType::LOW_SHELF || type == FilterType::HIGH_SHELF) {
         y = sinOmega / 2.0 * sqrt((1.0 / gain + gain) * (1.0 / (double) qFactor - 1.0) + 2.0);
         z = sqrt(gain) * 2.0 * y;
-    } else if (!param_7) {
+    } else if (param_7) {
-        y = sinOmega / ((double) qFactor * 2.0);
+        y = sinh(((double) qFactor * log(2.0) * omega / 2.0) / sinOmega) * sinOmega;
         z = -1.0; // Unused in this case
     } else {
-        y = sinh(((double) qFactor * log(2.0) * omega / 2.0) / sinOmega) * sinOmega;
+        y = sinOmega / ((double) qFactor + (double) qFactor);
         z = -1.0; // Unused in this case
     }
 
@@ -143,13 +143,13 @@ MultiBiquad::RefreshFilter(FilterType type, float gainAmp, float frequency, uint
         }
     }
 
-    this->x2 = 0.0;
     this->x1 = 0.0;
-    this->y2 = 0.0;
+    this->x2 = 0.0;
     this->y1 = 0.0;
+    this->y2 = 0.0;
 
-    this->a1 = -a1 / a0;
+    this->a1 = -(a1 / a0);
-    this->a2 = -a2 / a0;
+    this->a2 = -(a2 / a0);
     this->b0 = b0 / a0;
     this->b1 = b1 / a0;
     this->b2 = b2 / a0;