# HG changeset patch
# User Chris Cannam
# Date 1406307008 -3600
# Node ID 41b09144491bda6e2a1330af29b79c81532a1a7f
# Parent  d960c4931501f76d30b00778807c26ae56d84de1
Start to calculate some roughly stereo-related things

diff -r d960c4931501 -r 41b09144491b Azi.cpp
--- a/Azi.cpp	Fri Jul 25 17:11:57 2014 +0100
+++ b/Azi.cpp	Fri Jul 25 17:50:08 2014 +0100
@@ -1,12 +1,13 @@
 
 #include "Azi.h"
 
+#include <cmath>
+
+using std::vector;
 
 Azi::Azi(float inputSampleRate) :
-    Plugin(inputSampleRate)
-    // Also be sure to set your plugin parameters (presumably stored
-    // in member variables) to their default values here -- the host
-    // will not do that for you
+    Plugin(inputSampleRate),
+    m_width(32)
 {
 }
 
@@ -81,13 +82,13 @@
 size_t
 Azi::getMinChannelCount() const
 {
-    return 1;
+    return 2;
 }
 
 size_t
 Azi::getMaxChannelCount() const
 {
-    return 1;
+    return 2;
 }
 
 Azi::ParameterList
@@ -106,35 +107,18 @@
     // not explicitly set your parameters to their defaults for you if
     // they have not changed in the mean time.
 
-    ParameterDescriptor d;
-    d.identifier = "parameter";
-    d.name = "Some Parameter";
-    d.description = "";
-    d.unit = "";
-    d.minValue = 0;
-    d.maxValue = 10;
-    d.defaultValue = 5;
-    d.isQuantized = false;
-    list.push_back(d);
-
     return list;
 }
 
 float
 Azi::getParameter(string identifier) const
 {
-    if (identifier == "parameter") {
-        return 5; // return the ACTUAL current value of your parameter here!
-    }
     return 0;
 }
 
 void
 Azi::setParameter(string identifier, float value) 
 {
-    if (identifier == "parameter") {
-        // set the actual value of your parameter
-    }
 }
 
 Azi::ProgramList
@@ -168,12 +152,12 @@
     // Every plugin must have at least one output.
 
     OutputDescriptor d;
-    d.identifier = "output";
-    d.name = "My Output";
+    d.identifier = "plan";
+    d.name = "Plan";
     d.description = "";
     d.unit = "";
     d.hasFixedBinCount = true;
-    d.binCount = 1;
+    d.binCount = m_width * 2 + 1;
     d.hasKnownExtents = false;
     d.isQuantized = false;
     d.sampleType = OutputDescriptor::OneSamplePerStep;
@@ -189,7 +173,7 @@
     if (channels < getMinChannelCount() ||
 	channels > getMaxChannelCount()) return false;
 
-    // Real initialisation work goes here!
+    m_blockSize = blockSize;
 
     return true;
 }
@@ -200,11 +184,71 @@
     // Clear buffers, reset stored values, etc
 }
 
+float
+Azi::rms(const float *buffer, int size)
+{
+    float sum = 0;
+    if (size == 0) {
+	return 0;
+    }
+    for (int i = 0; i < size; ++i) {
+	sum += buffer[i] * buffer[i];
+    }
+    return sqrt(sum / size);
+}
+
 Azi::FeatureSet
 Azi::process(const float *const *inputBuffers, Vamp::RealTime timestamp)
 {
-    // Do actual work!
-    return FeatureSet();
+    const float *left = inputBuffers[0];
+    const float *right = inputBuffers[1];
+
+    float *mixed = new float[m_blockSize];
+    for (int i = 0; i < m_blockSize; ++i) {
+	mixed[i] = inputBuffers[0][i] + inputBuffers[1][i];
+    }
+    float mixedRms = rms(mixed, m_blockSize);
+
+    FeatureSet fs;
+    Feature f;
+
+    float *unpanned = new float[m_blockSize];
+
+    vector<float> levels;
+
+    for (int j = -m_width; j <= m_width; ++j) {
+
+	float unpan = float(j) / m_width;
+
+	float leftGain = 1.f, rightGain = 1.f;
+	if (unpan > 0.f) leftGain *= 1.f - unpan;
+	if (unpan < 0.f) rightGain *= unpan + 1.f;
+
+	for (int i = 0; i < m_blockSize; ++i) {
+	    unpanned[i] = (leftGain * left[i]) - (rightGain * right[i]);
+	}
+
+	float unpannedRms = rms(unpanned, m_blockSize);
+	levels.push_back((mixedRms - unpannedRms) / mixedRms);
+    }
+
+    for (int i = 1; i+1 < int(levels.size()); ++i) {
+	f.values.push_back(1.f - levels[i]);
+/*
+	if (levels[i] < levels[i-1] && levels[i] < levels[i+1]) {
+	    f.values.push_back(levels[i]);
+	} else {
+	    f.values.push_back(0);
+	}
+*/
+    }
+
+    delete[] unpanned;
+    delete[] mixed;
+
+    fs[0].push_back(f);
+
+    return fs;
 }
 
 Azi::FeatureSet
diff -r d960c4931501 -r 41b09144491b Azi.h
--- a/Azi.h	Fri Jul 25 17:11:57 2014 +0100
+++ b/Azi.h	Fri Jul 25 17:50:08 2014 +0100
@@ -44,7 +44,10 @@
     FeatureSet getRemainingFeatures();
 
 protected:
-    // plugin-specific data and methods go here
+    int m_width;
+    int m_blockSize;
+
+    float rms(const float *buffer, int size);
 };
 
 
diff -r d960c4931501 -r 41b09144491b Makefile.inc
--- a/Makefile.inc	Fri Jul 25 17:11:57 2014 +0100
+++ b/Makefile.inc	Fri Jul 25 17:50:08 2014 +0100
@@ -17,7 +17,7 @@
 PLUGIN	:= azi$(PLUGIN_EXT)
 
 PLUGIN_HEADERS := $(SRC_DIR)/Azi.h
-PLUGIN_SOURCES := $(SRC_DIR)/Azi.cpp
+PLUGIN_SOURCES := $(SRC_DIR)/Azi.cpp $(SRC_DIR)/plugins.cpp
 
 HEADERS	     := $(PLUGIN_HEADERS)
 SOURCES	     := $(PLUGIN_SOURCES)