Add moving average filter.

lnd3 · Oct 3, 2024 · 80eb4c0 · 80eb4c0
1 parent 24c449c
commit 80eb4c0
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Showing 3 changed files with 59 additions and 7 deletions.
diff --git a/packages/nodegraph/include/nodegraph/operations/NodeGraphOpFilter.h b/packages/nodegraph/include/nodegraph/operations/NodeGraphOpFilter.h
@@ -120,5 +120,25 @@ namespace l::nodegraph {
         l::audio::FilterRWA<float> mScaleFilter;
     };
 
+
+    /*********************************************************************/
+    class GraphFilterMovingAverage : public GraphFilterBase {
+    public:
+        GraphFilterMovingAverage(NodeGraphBase* node, int32_t kernelSize) :
+            GraphFilterBase(node, "Moving Average"),
+            mKernelSize(kernelSize)
+        {
+            mInputManager.AddInput(InputIterationType::SAMPLED, AddInput("Kernel Size", 1.0f, 1, 1.0f, static_cast<float>(mKernelSize)));
+        }
+        virtual ~GraphFilterMovingAverage() = default;
+
+        virtual void ResetInput() override;
+        virtual void ResetSignal() override;
+        virtual float ProcessSignal(float input, float cutoff, float resonance) override;
+    protected:
+        int32_t mKernelSize = 150;
+        int32_t mFilterStateIndex = -1;
+        std::vector<float> mFilterState;
+    };
 }
 
diff --git a/packages/nodegraph/source/common/NodeGraphSchema.cpp b/packages/nodegraph/source/common/NodeGraphSchema.cpp
@@ -91,6 +91,9 @@ namespace l::nodegraph {
         case 152:
             node = mMainNodeGraph.NewNode<l::nodegraph::GraphFilterChamberlain2pole>(NodeType::Default);
             break;
+        case 153:
+            node = mMainNodeGraph.NewNode<l::nodegraph::GraphFilterMovingAverage>(NodeType::Default, 150);
+            break;
 
         case 200:
             node = mMainNodeGraph.NewNode<l::nodegraph::GraphOutputDebug>(NodeType::ExternalOutput);
@@ -269,6 +272,7 @@ namespace l::nodegraph {
             RegisterNodeType("Filter", 150, "Lowpass");
             RegisterNodeType("Filter", 151, "Highpass");
             RegisterNodeType("Filter", 152, "Chamberlin two-pole (4 mode)");
+            RegisterNodeType("Filter", 153, "Moving Average");
         }
         else if (typeGroup == "Output") {
             RegisterNodeType("Output", 200, "Debug");

diff --git a/packages/nodegraph/source/common/operations/NodeGraphOpFilter.cpp b/packages/nodegraph/source/common/operations/NodeGraphOpFilter.cpp
@@ -12,16 +12,11 @@ namespace l::nodegraph {
     /* Stateful filtering operations */
         /*********************************************************************/
     void GraphFilterBase::Reset() {
+		NodeGraphOp::Reset();
+
         mSync = 0.0f;
         mSamplesUntilUpdate = 0.0f;
 
-        mNode->SetInput(0, 0.0f);
-        mNode->SetInput(2, 0.5f);
-        mNode->SetInput(3, 0.5f);
-        mNode->SetInputBound(0, InputBound::INPUT_0_TO_1);
-        mNode->SetInputBound(2, InputBound::INPUT_0_TO_1);
-        mNode->SetInputBound(3, InputBound::INPUT_0_TO_1);
-
         ResetInput();
         ResetSignal();
     }
@@ -125,4 +120,37 @@ namespace l::nodegraph {
 
         return mState.at(mMode);
     }
+
+    /*********************************************************************/
+    void GraphFilterMovingAverage::ResetInput() {
+    }
+
+    void GraphFilterMovingAverage::ResetSignal() {
+        mFilterState.resize(mKernelSize);
+        mFilterStateIndex = -1;
+    }
+
+    float GraphFilterMovingAverage::ProcessSignal(float input, float, float) {
+        if (mFilterStateIndex < 0) {
+            for (int32_t i = 0; i < mFilterState.size(); i++) {
+                mFilterState.at(i) = input;
+            }
+            mFilterStateIndex = 0;
+        }
+
+        mFilterState[mFilterStateIndex] = input;
+        float width = mInputManager.GetValueNext(mNumDefaultInputs + 0);
+        int32_t widthInt = static_cast<int32_t>(width);
+        mFilterStateIndex = (mFilterStateIndex + 1) % widthInt;
+
+        if (widthInt == 1) {
+            return input;
+        }
+
+        float outVal = 0.0;
+        for (int32_t i = 0; i < widthInt; i++) {
+            outVal += mFilterState[i];
+        }
+        return outVal / width;
+    }
 }