more work

core/src/gui/widgets/waterfall.cpp

@@ -689,6 +689,7 @@ namespace ImGui {
 
     void WaterFall::onResize() {
         std::lock_guard<std::recursive_mutex> lck(latestFFTMtx);
+        std::lock_guard<std::mutex> lck2(smoothingBufMtx);
         // return if widget is too small
         if (widgetSize.x < 100 || widgetSize.y < 100) {
             return;
@@ -740,14 +741,23 @@ namespace ImGui {
         }
         latestFFTHold = new float[dataWidth];
 
+        // Reallocate smoothing buffer
+        if (fftSmoothing) {
+            if (smoothingBuf) { delete[] smoothingBuf; }
+            smoothingBuf = new float[dataWidth];
+            for (int i = 0; i < dataWidth; i++) {
+                smoothingBuf[i] = -1000.0f; 
+            }
+        }
+
         if (waterfallVisible) {
             delete[] waterfallFb;
             waterfallFb = new uint32_t[dataWidth * waterfallHeight];
             memset(waterfallFb, 0, dataWidth * waterfallHeight * sizeof(uint32_t));
         }
         for (int i = 0; i < dataWidth; i++) {
-            latestFFT[i] = -1000.0; // Hide everything
-            latestFFTHold[i] = -1000.0;
+            latestFFT[i] = -1000.0f; // Hide everything
+            latestFFTHold[i] = -1000.0f;
         }
 
         fftAreaMin = ImVec2(widgetPos.x + (50.0f * style::uiScale), widgetPos.y + (9.0f * style::uiScale));
@@ -873,6 +883,15 @@ namespace ImGui {
             fftLines = 1;
         }
 
+        // Apply smoothing if enabled
+        if (fftSmoothing && latestFFT != NULL && smoothingBuf != NULL && fftLines != 0) {
+            std::lock_guard<std::mutex> lck2(smoothingBufMtx);
+            volk_32f_s32f_multiply_32f(latestFFT, latestFFT, smoothingAlpha, dataWidth);
+            volk_32f_s32f_multiply_32f(smoothingBuf, smoothingBuf, smoothingBeta, dataWidth);
+            volk_32f_x2_add_32f(smoothingBuf, latestFFT, smoothingBuf, dataWidth);
+            memcpy(latestFFT, smoothingBuf, dataWidth * sizeof(float));
+        }
+
         if (selectedVFO != "" && vfos.size() > 0) {
             float dummy;
             calculateVFOSignalInfo(waterfallVisible ? &rawFFTs[currentFFTLine * rawFFTSize] : rawFFTs, vfos[selectedVFO], dummy, selectedVFOSNR);
@@ -1110,6 +1129,36 @@ namespace ImGui {
         fftHoldSpeed = speed;
     }
 
+    void WaterFall::setFFTSmoothing(bool enabled) {
+        std::lock_guard<std::mutex> lck(smoothingBufMtx);
+        fftSmoothing = enabled;
+
+        // Free buffer if not null
+        if (smoothingBuf) {delete[] smoothingBuf; }
+
+        // If disabled, stop here
+        if (!enabled) {
+            smoothingBuf = NULL;
+            return;
+        }
+
+        // Allocate and copy existing FFT into it
+        smoothingBuf = new float[dataWidth];
+        if (latestFFT) {
+            std::lock_guard<std::recursive_mutex> lck2(latestFFTMtx);
+            memcpy(smoothingBuf, latestFFT, dataWidth * sizeof(float));
+        }
+        else {
+            memset(smoothingBuf, 0, dataWidth * sizeof(float));
+        }
+    }
+
+    void WaterFall::setFFTSmoothingSpeed(float speed) {
+        std::lock_guard<std::mutex> lck(smoothingBufMtx);
+        smoothingAlpha = speed;
+        smoothingBeta = 1.0f - speed;
+    }
+
     float* WaterFall::acquireLatestFFT(int& width) {
         latestFFTMtx.lock();
         if (!latestFFT) {

core/src/gui/widgets/waterfall.h

@@ -169,6 +169,9 @@ namespace ImGui {
         void setFFTHold(bool hold);
         void setFFTHoldSpeed(float speed);
 
+        void setFFTSmoothing(bool enabled);
+        void setFFTSmoothingSpeed(float speed);
+
         float* acquireLatestFFT(int& width);
         void releaseLatestFFT();
 
@@ -270,6 +273,7 @@ namespace ImGui {
         std::recursive_mutex buf_mtx;
         std::recursive_mutex latestFFTMtx;
         std::mutex texMtx;
+        std::mutex smoothingBufMtx;
 
         float vRange;
 
@@ -304,8 +308,9 @@ namespace ImGui {
         //std::vector<std::vector<float>> rawFFTs;
         int rawFFTSize;
         float* rawFFTs = NULL;
-        float* latestFFT;
-        float* latestFFTHold;
+        float* latestFFT = NULL;
+        float* latestFFTHold = NULL;
+        float* smoothingBuf = NULL;
         int currentFFTLine = 0;
         int fftLines = 0;
 
@@ -325,6 +330,10 @@ namespace ImGui {
         bool fftHold = false;
         float fftHoldSpeed = 0.3f;
 
+        bool fftSmoothing = false;
+        float smoothingAlpha = 0.5;
+        float smoothingBeta = 0.5;
+
         // UI Select elements
         bool fftResizeSelect = false;
         bool freqScaleSelect = false;