Tweak the amplitude stage a bit (#132)

1. Consolidate some of the code into the param 2. If the param is at 0db don't touch the signal at all 3. Fix a -0.00db display which arose
baconpaul · Jun 11, 2024 · 349fd89 · 349fd89
1 parent c7dd166
commit 349fd89
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Showing 2 changed files with 39 additions and 18 deletions.
diff --git a/src-juce/AWConsolidatedProcessor.cpp b/src-juce/AWConsolidatedProcessor.cpp
@@ -227,16 +227,15 @@ template <typename T> void AWConsolidatedAudioProcessor::processBlockT(juce::Aud
         awProcessor->setParameter(i, fxParams[i]->get());
     }
 
-    T inScale = inLev->get();
-    inScale = inScale * inScale * inScale * CubicDBParam::maxLev;
-
-    T outScale = outLev->get();
-    outScale = outScale * outScale * outScale * CubicDBParam::maxLev;
+    auto inScale = inLev->getAmplitude<T>();
+    auto inScaleActive = inLev->isAmplifiyingOrAttenuating();
+    auto outScale = outLev->getAmplitude<T>();
+    auto outScaleActrive = outLev->isAmplifiyingOrAttenuating();
 
     if constexpr (std::is_same_v<T, float>)
     {
         // FIXME - deal with very large block case by not skipping level
-        if (buffer.getNumSamples() < maxInBlock)
+        if (inScaleActive && buffer.getNumSamples() < maxInBlock)
         {
             for (int i = 0; i < buffer.getNumSamples(); ++i)
             {
@@ -250,7 +249,7 @@ template <typename T> void AWConsolidatedAudioProcessor::processBlockT(juce::Aud
     }
     else
     {
-        if (buffer.getNumSamples() < maxInBlock)
+        if (inScaleActive && buffer.getNumSamples() < maxInBlock)
         {
             for (int i = 0; i < buffer.getNumSamples(); ++i)
             {
@@ -265,10 +264,13 @@ template <typename T> void AWConsolidatedAudioProcessor::processBlockT(juce::Aud
                                             buffer.getNumSamples());
     }
 
-    for (int i = 0; i < buffer.getNumSamples(); ++i)
+    if (outScaleActrive)
     {
-        outputs[0][i] *= outScale;
-        outputs[1][i] *= outScale;
+        for (int i = 0; i < buffer.getNumSamples(); ++i)
+        {
+            outputs[0][i] *= outScale;
+            outputs[1][i] *= outScale;
+        }
     }
 }
 
@@ -410,9 +412,9 @@ void AWConsolidatedAudioProcessor::setStateInformation(const void *data, int siz
                 fxParams[i]->setValueNotifyingHost(f);
             }
 
-            auto il = xmlState->getDoubleAttribute("inlev", std::cbrt(1.f/CubicDBParam::maxLev));
+            auto il = xmlState->getDoubleAttribute("inlev", CubicDBParam::defaultVal);
             inLev->setValueNotifyingHost(il);
-            auto ol = xmlState->getDoubleAttribute("outlev", std::cbrt(1.f/CubicDBParam::maxLev));
+            auto ol = xmlState->getDoubleAttribute("outlev", CubicDBParam::defaultVal);
             outLev->setValueNotifyingHost(ol);
         }
 

diff --git a/src-juce/AWConsolidatedProcessor.h b/src-juce/AWConsolidatedProcessor.h
@@ -206,23 +206,28 @@ class AWConsolidatedAudioProcessor : public juce::AudioProcessor,
     struct CubicDBParam : public APFPublicDefault
     {
         static constexpr float maxDb{18.0};
-        static constexpr float maxLev{7.943282347242815}; // pow(10, maxDb/20)
+        static constexpr double maxLev{7.943282347242815}; // pow(10, maxDb/20)
+        static constexpr double defaultVal{0.5011872336272724}; // 1.0 / cbrt(maxLeb)
         CubicDBParam(const juce::ParameterID &id, const juce::String &parameterName)
             : APFPublicDefault(id, parameterName, juce::NormalisableRange<float>(0.0, 1.0),
-                               std::cbrt(1.f / maxLev))
+                               defaultVal)
         {
         }
 
         juce::String getText(float f, int i) const override
         {
-            auto val = f;
+            auto val = (double)f;
             if (val <= 0)
             {
                 return "-inf";
             }
 
             auto v3 = val * val * val * maxLev;
-            auto db = 20 * std::log10(v3);
+
+            // This 1e-6 pushes the display off -0.00db to 0.00db
+            // which happens due to float truncation since the
+            // param is float valued
+            auto db = 20 * std::log10(v3 + 1e-6);
             char res[64];
             snprintf(res, 63, "%.2f dB", db);
             return res;
@@ -239,13 +244,27 @@ class AWConsolidatedAudioProcessor : public juce::AudioProcessor,
             auto lv = std::cbrt(db / maxLev);
             if (lv < 0 || lv > 1)
             {
-                return std::cbrt(1.f / maxLev);
+                return defaultVal;
             }
 
             return (float)lv;
         }
 
-        float getDefaultValue() const override { return std::cbrt(1.0 / maxLev); }
+        float getDefaultValue() const override { return defaultVal; }
+
+        template<typename T>
+        T getAmplitude() const {
+            T lev = (T)get();
+            lev = lev * lev * lev * maxLev;
+            return lev;
+        }
+
+        bool isAmplifiyingOrAttenuating() const
+        {
+            return std::fabs(get() - defaultVal) > 5e-6;
+        }
+
+
     };
 
     //==============================================================================