From 44387fc6606057393b5026ce0d2707a016037347 Mon Sep 17 00:00:00 2001
From: John Glover <j@johnglover.net>
Date: Fri, 20 Jul 2012 17:46:30 +0100
Subject: [peak_detection] Add C++ implementation of SndObj peak detection.

---
 src/simpl/peak_detection.cpp | 75 ++++++++++++++++++++++++++++++++++++++++++++
 src/simpl/peak_detection.h   | 28 ++++++++++++++++-
 2 files changed, 102 insertions(+), 1 deletion(-)

(limited to 'src')

diff --git a/src/simpl/peak_detection.cpp b/src/simpl/peak_detection.cpp
index 0f118b3..18fca8e 100644
--- a/src/simpl/peak_detection.cpp
+++ b/src/simpl/peak_detection.cpp
@@ -290,3 +290,78 @@ Frames SMSPeakDetection::find_peaks(int audio_size, sample* audio) {
 
     return _frames;
 }
+
+
+// ---------------------------------------------------------------------------
+// SndObjPeakDetection
+// ---------------------------------------------------------------------------
+SndObjPeakDetection::SndObjPeakDetection() {
+    _input = new SndObj();
+    _input->SetVectorSize(_frame_size);
+    _window = new HammingTable(_frame_size, 0.5);
+    _ifgram = new IFGram(_window, _input, 1, _frame_size, _hop_size);
+    _analysis = new SinAnal(_ifgram, _threshold, _max_peaks);
+    _threshold = 0.003;
+}
+
+SndObjPeakDetection::~SndObjPeakDetection() {
+    delete _input;
+    delete _window;
+    delete _ifgram;
+    delete _analysis;
+}
+
+void SndObjPeakDetection::frame_size(int new_frame_size) {
+    _frame_size = new_frame_size;
+    _input->SetVectorSize(_frame_size);
+
+    if(_window) {
+        delete _window;
+    }
+    _window = new HammingTable(_frame_size, 0.5);
+
+    _ifgram->Connect("window", _window);
+    _ifgram->Set("fft size", _frame_size);
+}
+
+void SndObjPeakDetection::hop_size(int new_hop_size) {
+    _hop_size = new_hop_size;
+    _ifgram->Set("hop size", _hop_size);
+}
+
+void SndObjPeakDetection::max_peaks(int new_max_peaks) {
+    _max_peaks = new_max_peaks;
+    _analysis->Set("max tracks", _max_peaks);
+}
+
+Peaks SndObjPeakDetection::find_peaks_in_frame(Frame* frame) {
+    Peaks peaks;
+
+    _input->PushIn(frame->audio(), frame->size());
+    _ifgram->DoProcess();
+    int num_peaks = _analysis->FindPeaks();
+
+    for(int i = 0; i < num_peaks; i++) {
+        Peak* p = new Peak();
+        p->amplitude = _analysis->Output(i * 3);
+        p->frequency = _analysis->Output((i * 3) + 1);
+        p->phase = _analysis->Output((i * 3) + 2);
+        peaks.push_back(p);
+
+        frame->add_peak(p);
+
+        // TODO: check that peaks are _min_peak_separation apart
+        //
+        // if not peaks:
+        //     peaks.append(p)
+        // else:
+        //     if np.abs(p.frequency - peaks[-1].frequency) > self._min_peak_separation:
+        //         peaks.append(p)
+        //     else:
+        //         if p.amplitude > peaks[-1].amplitude:
+        //             peaks.remove(peaks[-1])
+        //             peaks.append(p)
+    }
+
+    return peaks;
+}
diff --git a/src/simpl/peak_detection.h b/src/simpl/peak_detection.h
index e10c2c3..bcc918b 100644
--- a/src/simpl/peak_detection.h
+++ b/src/simpl/peak_detection.h
@@ -7,6 +7,11 @@ extern "C" {
     #include "sms.h"
 }
 
+#include "SndObj.h"
+#include "HammingTable.h"
+#include "IFGram.h"
+#include "SinAnal.h"
+
 using namespace std;
 
 
@@ -90,6 +95,27 @@ class SMSPeakDetection : public PeakDetection {
 };
 
 
-} // end of namespace Simpl
+// ---------------------------------------------------------------------------
+// SndObjPeakDetection
+// ---------------------------------------------------------------------------
+class SndObjPeakDetection : public PeakDetection {
+    private:
+        SndObj* _input;
+        HammingTable* _window;
+        IFGram* _ifgram;
+        SinAnal* _analysis;
+        sample _threshold;
+
+    public:
+        SndObjPeakDetection();
+        ~SndObjPeakDetection();
+        void frame_size(int new_frame_size);
+        void hop_size(int new_hop_size);
+        void max_peaks(int new_max_peaks);
+        Peaks find_peaks_in_frame(Frame* frame);
+};
+
+
+} // end of namespace simpl
 
 #endif
-- 
cgit v1.2.3