From 26476c375f4288fa8076bba146fe0a0b87c2f238 Mon Sep 17 00:00:00 2001
From: Paul Brossier <piem@piem.org>
Date: Thu, 21 Jan 2016 09:09:35 +0100
Subject: [PATCH] src/ofxAubioFilterDetect.*: add cut-off high and low pass
 detection

---
 src/ofxAubioFilterDetect.cpp | 102 +++++++++++++++++++++++++++++++++++++++++++
 src/ofxAubioFilterDetect.h   |  54 +++++++++++++++++++++++
 2 files changed, 156 insertions(+)
 create mode 100644 src/ofxAubioFilterDetect.cpp
 create mode 100644 src/ofxAubioFilterDetect.h

diff --git a/src/ofxAubioFilterDetect.cpp b/src/ofxAubioFilterDetect.cpp
new file mode 100644
index 0000000..2d0dab8
--- /dev/null
+++ b/src/ofxAubioFilterDetect.cpp
@@ -0,0 +1,102 @@
+/*
+  Copyright (C) 2015 Paul Brossier <piem@aubio.org>
+
+  This file is part of ofxAubio.
+
+  ofxAubio is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  aubio is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with aubio.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+#include <math.h>
+#define LIN2DB(v) (20.0*log10f(v))
+
+#include "ofxAubioFilterDetect.h"
+#include "ofLog.h"
+
+ofxAubioFilterDetect::ofxAubioFilterDetect()
+    : bands(NULL)
+{
+    lag = 50;
+}
+
+ofxAubioFilterDetect::~ofxAubioFilterDetect()
+{
+}
+
+void ofxAubioFilterDetect::setup()
+{
+    setup("default", 512, 256, 44100);
+}
+void ofxAubioFilterDetect::setup(string method, int buf_s, int hop_s, int samplerate)
+{
+    hop_size = hop_s;
+    buf_size = buf_s;
+}
+
+void ofxAubioFilterDetect::setBands(ofxAubioMelBands & _bands) {
+    bands = &_bands;
+}
+
+void ofxAubioFilterDetect::audioIn(float * input, int bufferSize, int nChannels)
+{
+    uint_t i;
+    for (i = 0; i < bufferSize; i++) {
+        // run aubio block when appropriate
+        curpos += 1;
+        if (curpos == hop_size)
+        {
+            blockAudioIn();
+            curpos = 0;
+        }
+    }
+}
+
+void ofxAubioFilterDetect::blockAudioIn() {
+    energies.push_back(bands->energies);
+    if (energies.size() > lag) {
+        energies.erase (energies.begin());
+    }
+    filterDetect();
+}
+
+void ofxAubioFilterDetect::filterDetect() {
+    if (energies.size() >= lag) {
+        max_low_cutoff = 0;
+        for (int i = 0; i < bands->nBands; i ++) {
+            float band_sum = 0;
+            for (int j = 0; j < lag; j ++) {
+                band_sum += (energies[energies.size() - j - 1][i]);
+            }
+            if (band_sum < 0.01) {
+                max_low_cutoff = i;
+            } else {
+                break;
+            }
+        }
+        min_high_cutoff = 0;
+        for (int i = bands->nBands - 1; i >= 0; i --) {
+            float band_sum = 0;
+            for (int j = 0; j < lag; j ++) {
+                band_sum += (energies[energies.size() - j - 1][i]);
+            }
+            if (band_sum < 0.0001) {
+                min_high_cutoff = bands->nBands - 1 - i;
+            } else {
+                break;
+            }
+        }
+        //ofLog() << "got min_high_cutoff: " << min_high_cutoff
+        //    << " max_low_cutoff: " << max_low_cutoff;
+    }
+}
diff --git a/src/ofxAubioFilterDetect.h b/src/ofxAubioFilterDetect.h
new file mode 100644
index 0000000..7a0151a
--- /dev/null
+++ b/src/ofxAubioFilterDetect.h
@@ -0,0 +1,54 @@
+/*
+  Copyright (C) 2015 Paul Brossier <piem@aubio.org>
+
+  This file is part of ofxAubio.
+
+  ofxAubio is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  aubio is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with aubio.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+#pragma once
+
+#include <iostream>
+#include <aubio/aubio.h>
+#include "ofEvents.h"
+#include "ofxAubioBlock.h"
+#include "ofxAubioOnset.h"
+#include "ofxAubioBeat.h"
+#include "ofxAubioMelBands.h"
+
+class ofxAubioFilterDetect: public ofxAubioBlock {
+
+    public:
+
+       ofxAubioFilterDetect();
+       ~ofxAubioFilterDetect();
+
+       ofxAubioMelBands *bands;
+       void setBands(ofxAubioMelBands & bands);
+       std::vector<float *>energies;
+
+       void setup();
+       void setup(std::string method, int buf_s, int hop_s, int samplerate);
+
+       void audioIn(float *input, int bufferSize, int nChannels);
+
+       void filterDetect();
+
+       int lag;
+       int max_low_cutoff;
+       int min_high_cutoff;
+    private:
+       void blockAudioIn();
+};
-- 
2.11.0