m3, ui/ux, and more

modules/astra-scope/cpp/oscilloscope.h

@@ -0,0 +1,85 @@
+#pragma once
+
+#include "dsp_utils.h"
+#include <vector>
+#include <cstdint>
+
+namespace Visualizer {
+
+struct OscilloscopeResult {
+    float triggerIndex;
+    int samplesToShow;
+    float detectedPitch;
+};
+
+// Circular buffer size (same as pulse-visualizer)
+constexpr size_t OSCILLOSCOPE_BUFFER_SIZE = 32768;
+
+class Oscilloscope {
+public:
+    Oscilloscope();
+
+    // Configuration
+    void setSampleRate(float sampleRate);
+    void setPitchLock(bool enabled);
+    void setDisplaySamples(int samples);
+
+    // Push samples into circular buffer (continuous capture)
+    void pushSamples(const float* samples, size_t count);
+
+    // Process and find trigger point (uses circular buffer)
+    OscilloscopeResult process();
+
+    // Legacy: Process snapshot (for backwards compatibility)
+    OscilloscopeResult processSnapshot(const float* audioData, size_t length);
+
+    // Get current write position
+    size_t getWritePos() const { return writePos_; }
+
+    // Get samples from circular buffer (for rendering)
+    void getSamples(float* output, size_t startPos, size_t count) const;
+
+    // Get samples with sub-sample interpolation (preserves trigger precision)
+    void getSamplesInterpolated(float* output, float startPos, size_t count) const;
+
+    // Reset state
+    void reset();
+
+private:
+    float sampleRate_;
+    bool pitchLock_;
+    int displaySamples_;
+
+    // Circular buffer for continuous audio
+    std::vector<float> circularBuffer_;
+    std::vector<float> filteredBuffer_;
+    size_t writePos_;
+
+    // Linear-phase FIR bandpass filter for stable trigger detection
+    DSP::FIRFilter bandpassFilter_;
+    float lastFilterPitch_;  // Track pitch for filter redesign
+
+    // High shelf filter to reduce HF before pitch detection
+    DSP::BiquadFilter pitchAnalysisShelf_;
+
+    // Display filtering (high shelf + steep lowpass)
+    DSP::BiquadFilter displayShelf_;      // High shelf for display
+    DSP::BiquadFilter displayLowpass1_;   // First stage of cascaded lowpass
+    DSP::BiquadFilter displayLowpass2_;   // Second stage (4th order total = 24dB/oct)
+    std::vector<float> displayBuffer_;    // Lowpass filtered samples for tracking
+    std::vector<float> visualBuffer_;     // Visual-only samples (display shelf applied)
+
+    // Pitch detection lowpass (after existing high shelf)
+    DSP::BiquadFilter pitchLowpass1_;     // First stage
+    DSP::BiquadFilter pitchLowpass2_;     // Second stage
+
+    float lastTrigger_;
+    float smoothedPitch_;
+    int pitchSamplesProcessed_;  // Track samples for adaptive smoothing
+
+    // Internal helpers
+    void updateFiltered();
+    float findTriggerBackwards(size_t target, size_t range);
+};
+
+} // namespace Visualizer