wip: added sampling period measurement averaging using moving avg filter

CMakeLists.txt

@@ -111,6 +111,7 @@ set(PROJECT_SOURCES
     ${CMAKE_CURRENT_SOURCE_DIR}/src/TargetMemoryHandler/JlinkHandler.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/Plot/Plot.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/Variable/Variable.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/src/MovingAverage/MovingAverage.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/ConfigHandler/ConfigHandler.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/FileHandler/NFDFileHandler.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/ImguiPlugins/ImguiPlugins.cpp
@@ -168,6 +169,7 @@ target_include_directories(${EXECUTABLE} PRIVATE
     ${CMAKE_CURRENT_SOURCE_DIR}/src/TargetMemoryHandler
     ${CMAKE_CURRENT_SOURCE_DIR}/src/Plot
     ${CMAKE_CURRENT_SOURCE_DIR}/src/ScrollingBuffer
+    ${CMAKE_CURRENT_SOURCE_DIR}/src/MovingAverage
     ${CMAKE_CURRENT_SOURCE_DIR}/src/Variable
     ${CMAKE_CURRENT_SOURCE_DIR}/src/ConfigHandler
     ${CMAKE_CURRENT_SOURCE_DIR}/src/ImguiPlugins

src/Gui/Gui.cpp

@@ -797,7 +797,7 @@ void Gui::drawAcqusitionSettingsWindow(AcqusitionWindowType type)
 		ImGui::OpenPopup("Acqusition Settings");
 
 	ImGui::SetNextWindowPos(ImGui::GetMainViewport()->GetCenter(), ImGuiCond_Appearing, ImVec2(0.5f, 0.5f));
-	ImGui::SetNextWindowSize(ImVec2(950 * contentScale, 400 * contentScale));
+	ImGui::SetNextWindowSize(ImVec2(950 * contentScale, 500 * contentScale));
 	if (ImGui::BeginPopupModal("Acqusition Settings", &showAcqusitionSettingsWindow, 0))
 	{
 		if (type == AcqusitionWindowType::VARIABLE)

src/Gui/GuiPlots.cpp

@@ -67,7 +67,7 @@ void Gui::drawPlotCurve(Plot* plot, ScrollingBuffer<double>& time, std::map<std:
 			PlotHandler::Settings settings = plotHandler->getSettings();
 			ImPlot::SetupAxis(ImAxis_Y1, NULL, ImPlotAxisFlags_AutoFit);
 			ImPlot::SetupAxis(ImAxis_X1, "time[s]", 0);
-			const double viewportWidth = plotHandler->getAverageSamplingFrequency() * settings.maxViewportPoints;
+			const double viewportWidth = (1.0 / plotHandler->getAverageSamplingFrequency()) * settings.maxViewportPoints;
 			const double min = *time.getLastElement() < viewportWidth ? 0.0f : *time.getLastElement() - viewportWidth;
 			const double max = min == 0.0f ? *time.getLastElement() : min + viewportWidth;
 			ImPlot::SetupAxisLimits(ImAxis_X1, min, max, ImPlotCond_Always);

src/MovingAverage/MovingAverage.cpp

@@ -0,0 +1,18 @@
+
+#include "MovingAverage.hpp"
+
+MovingAverage::MovingAverage(size_t samples_) : samples(samples_ > maxSamples ? maxSamples : samples_)
+{
+}
+
+double MovingAverage::filter(double sampleIn)
+{
+	bufferSum -= buffer[bufferIter];  // Remove last entry from sum
+	buffer[bufferIter] = sampleIn;	  // Add new entry in place of the last one
+	bufferSum += buffer[bufferIter];  // Add new entry to sum
+	bufferIter++;					  // Increase iterator
+	if (bufferIter >= samples)
+		bufferIter = 0;
+
+	return bufferSum / samples;
+}

src/MovingAverage/MovingAverage.hpp

@@ -0,0 +1,20 @@
+#ifndef MOVINGAVG_HPP
+#define MOVINGAVG_HPP
+
+#include <cstdint>
+
+class MovingAverage
+{
+   public:
+	MovingAverage(size_t samples_);
+	double filter(double sampleIn);
+
+   private:
+	static constexpr size_t maxSamples = 200;
+	size_t samples = 0;
+	double buffer[maxSamples] = {0};
+	size_t bufferIter = 0;
+	double bufferSum = 0;
+};
+
+#endif

src/PlotHandler/PlotHandler.cpp

@@ -61,7 +61,6 @@ void PlotHandler::dataHandler()
 	std::chrono::time_point<std::chrono::steady_clock> start;
 	uint32_t timer = 0;
 	double lastT = 0.0;
-	double sum = 0.0;
 
 	while (!done)
 	{
@@ -94,6 +93,9 @@ void PlotHandler::dataHandler()
 					}
 					plot->addTimePoint(entry.first);
 				}
+				/* filter sampling frequency */
+				averageSamplingPeriod = samplingPeriodFilter.filter((period - lastT));
+				lastT = period;
 				timer++;
 			}
 
@@ -120,12 +122,11 @@ void PlotHandler::dataHandler()
 						plot->addPoint(name, ser->var->getValue());
 					plot->addTimePoint(period);
 				}
+				/* filter sampling frequency */
+				averageSamplingPeriod = samplingPeriodFilter.filter((period - lastT));
+				lastT = period;
 				timer++;
 			}
-
-			sum += (period - lastT);
-			averageSamplingFrequency = sum / timer;
-			lastT = period;
 		}
 		else
 			std::this_thread::sleep_for(std::chrono::milliseconds(20));
@@ -140,7 +141,6 @@ void PlotHandler::dataHandler()
 				{
 					timer = 0;
 					lastT = 0.0;
-					sum = 0.0;
 					start = std::chrono::steady_clock::now();
 				}
 				else

src/PlotHandler/PlotHandler.hpp

@@ -9,6 +9,7 @@
 #include <thread>
 
 #include "IDebugProbe.hpp"
+#include "MovingAverage.hpp"
 #include "Plot.hpp"
 #include "PlotHandlerBase.hpp"
 #include "ScrollingBuffer.hpp"
@@ -40,7 +41,7 @@ class PlotHandler : public PlotHandlerBase
 	void setProbeSettings(const IDebugProbe::DebugProbeSettings& settings);
 
 	void setDebugProbe(std::shared_ptr<IDebugProbe> probe);
-	double getAverageSamplingFrequency() const { return averageSamplingFrequency; }
+	double getAverageSamplingFrequency() const { return 1.0 / averageSamplingPeriod; }
 
    private:
 	void dataHandler();
@@ -50,7 +51,8 @@ class PlotHandler : public PlotHandlerBase
 	std::unique_ptr<TargetMemoryHandler> varReader;
 	IDebugProbe::DebugProbeSettings probeSettings{};
 	Settings settings{};
-	double averageSamplingFrequency;
+	MovingAverage samplingPeriodFilter{100};
+	double averageSamplingPeriod;
 };
 
 #endif

src/TargetMemoryHandler/StlinkHandler.hpp

@@ -22,10 +22,7 @@ class StlinkHandler : public IDebugProbe
 
 	std::string getLastErrorMsg() const override;
 	std::vector<std::string> getConnectedDevices() override;
-	bool requiresAlignedAccessOnRead() override
-	{
-		return true;
-	}
+	bool requiresAlignedAccessOnRead() override { return true; }
 
    private:
 	stlink_t* sl = nullptr;