diff flattendynamics/flattendynamics-ladspa.cpp @ 366:5d0a2ebb4d17

Bring dependent libraries in to repo

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flattendynamics/flattendynamics-ladspa.cpp	Fri Jun 24 14:47:45 2016 +0100
@@ -0,0 +1,270 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+#include "flattendynamics-ladspa.h"
+
+#include <iostream>
+#include <cmath>
+
+using std::cerr;
+using std::endl;
+
+const float historySeconds = 4.f;
+const float catchUpSeconds = 0.2f;
+const float targetMaxRMS = 0.05f;
+const float rmsMaxDecay = 0.999f; // per sample
+const float maxGain = 10.f;
+
+const char *const
+FlattenDynamics::portNames[PortCount] =
+{
+    "Input",
+    "Output",
+    "Gain",
+};
+
+const LADSPA_PortDescriptor 
+FlattenDynamics::ports[PortCount] =
+{
+    LADSPA_PORT_INPUT  | LADSPA_PORT_AUDIO,
+    LADSPA_PORT_OUTPUT | LADSPA_PORT_AUDIO,
+    LADSPA_PORT_OUTPUT | LADSPA_PORT_CONTROL,
+};
+
+const LADSPA_PortRangeHint 
+FlattenDynamics::hints[PortCount] =
+{
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+};
+
+const LADSPA_Properties
+FlattenDynamics::properties = LADSPA_PROPERTY_HARD_RT_CAPABLE;
+
+const LADSPA_Descriptor 
+FlattenDynamics::ladspaDescriptor =
+{
+    0xf0b375, // "Unique" ID
+    "flattendynamics", // Label
+    properties,
+    "Flatten Dynamics", // Name
+    "Queen Mary, University of London", // Maker
+    "BSD", // Copyright
+    PortCount,
+    ports,
+    portNames,
+    hints,
+    0, // Implementation data
+    ladspaInstantiate,
+    ladspaConnectPort,
+    ladspaActivate,
+    ladspaRun,
+    0, // Run adding
+    0, // Set run adding gain
+    ladspaDeactivate,
+    ladspaCleanup
+};
+
+const LADSPA_Descriptor *
+FlattenDynamics::getDescriptor(unsigned long index)
+{
+    if (index == 0) return &ladspaDescriptor;
+    return 0;
+}
+
+FlattenDynamics::FlattenDynamics(int sampleRate) :
+    m_sampleRate(sampleRate),
+    m_input(0),
+    m_output(0),
+    m_pgain(0),
+    m_history(0),
+    m_histlen(0),
+    m_histwrite(0),
+    m_histread(0),
+    m_sumOfSquares(0.f),
+    m_rms(0.f),
+    m_maxRms(0.f),
+    m_gain(1.f)
+{
+    reset();
+}
+
+FlattenDynamics::~FlattenDynamics()
+{
+    delete[] m_history;
+}
+    
+LADSPA_Handle
+FlattenDynamics::ladspaInstantiate(const LADSPA_Descriptor *, unsigned long rate)
+{
+    FlattenDynamics *flatten = new FlattenDynamics(rate);
+    return flatten;
+}
+
+void
+FlattenDynamics::ladspaConnectPort(LADSPA_Handle handle,
+                                   unsigned long port, 
+                                   LADSPA_Data *location)
+{
+    FlattenDynamics *flatten = (FlattenDynamics *)handle;
+    if (ports[port] & LADSPA_PORT_INPUT) {
+        flatten->connectInputPort(Port(port), location);
+    } else {
+        flatten->connectOutputPort(Port(port), location);
+    }
+}
+
+void
+FlattenDynamics::ladspaActivate(LADSPA_Handle handle)
+{
+    FlattenDynamics *flatten = (FlattenDynamics *)handle;
+    flatten->reset();
+}
+
+void
+FlattenDynamics::ladspaRun(LADSPA_Handle handle, unsigned long samples)
+{
+    FlattenDynamics *flatten = (FlattenDynamics *)handle;
+    flatten->process(samples);
+}
+
+void
+FlattenDynamics::ladspaDeactivate(LADSPA_Handle handle)
+{
+    ladspaActivate(handle); // both functions just reset the plugin
+}
+
+void
+FlattenDynamics::ladspaCleanup(LADSPA_Handle handle)
+{
+    delete (FlattenDynamics *)handle;
+}
+
+void
+FlattenDynamics::connectInputPort(Port p, const float *location)
+{
+    const float **ports[PortCount] = {
+	&m_input, 0, 0,
+    };
+
+    *ports[int(p)] = location;
+}
+
+void
+FlattenDynamics::connectOutputPort(Port p, float *location)
+{
+    float **ports[PortCount] = {
+	0, &m_output, &m_pgain,
+    };
+
+    *ports[int(p)] = location;
+}
+
+void
+FlattenDynamics::reset()
+{
+    delete[] m_history;
+    m_histlen = int(round(m_sampleRate * historySeconds));
+    if (m_histlen < 1) m_histlen = 1;
+    m_history = new float[m_histlen];
+    for (int i = 0; i < m_histlen; ++i) {
+        m_history[i] = 0.f;
+    }
+    m_histwrite = 0;
+    m_histread = 0;
+
+    m_sumOfSquares = 0.0;
+    m_rms = 0.f;
+    m_maxRms = 0.f;
+    m_gain = 1.f;
+}
+
+void
+FlattenDynamics::updateParameters()
+{
+    if (m_pgain) *m_pgain = m_gain;
+}
+
+void
+FlattenDynamics::process(int sampleCount)
+{
+    if (!m_input || !m_output) return;
+
+    updateParameters();
+
+    for (int i = 0; i < sampleCount; ++i) {
+        m_output[i] = processSingle(m_input[i]);
+    }
+}
+
+float
+FlattenDynamics::processSingle(float f)
+{
+    updateRMS(f);
+
+    if (m_rms == 0.f) {
+        return f;
+    }
+
+    if (m_rms >= m_maxRms) {
+        m_maxRms = m_rms;
+    } else {
+        m_maxRms = m_rms + (m_maxRms - m_rms) * rmsMaxDecay;
+    }
+
+    float targetGain = targetMaxRMS / m_maxRms;
+
+    if (targetGain > maxGain) {
+        targetGain = maxGain;
+    }
+
+    float catchUpSamples = catchUpSeconds * m_sampleRate;
+    // asymptotic, could improve?
+    m_gain = m_gain + (targetGain - m_gain) / catchUpSamples;
+
+    if (fabsf(f) * m_gain > 1.f) {
+        m_gain = 1.f / fabsf(f);
+    }
+
+//    cerr << "target gain = " << targetGain << ", gain = " << m_gain << endl;
+    return f * m_gain;
+}
+
+void
+FlattenDynamics::updateRMS(float f)
+{
+    // We update the RMS values by maintaining a sum-of-last-n-squares
+    // total (which the RMS is the square root of 1/n of) and
+    // recording the last n samples of history in a circular
+    // buffer. When a sample drops off the start of the history, we
+    // remove the square of it from the sum-of-squares total; then we
+    // add the square of the new sample.
+
+    int nextWrite = (m_histwrite + 1) % m_histlen;
+
+    float lose = 0.f;
+
+    if (nextWrite == m_histread) {
+        // full
+        lose = m_history[m_histread];
+        m_histread = (m_histread + 1) % m_histlen;
+    }
+
+    m_history[m_histwrite] = f;
+    m_histwrite = nextWrite;
+
+    int fill = (m_histwrite - m_histread + m_histlen) % m_histlen;
+
+    m_sumOfSquares -= lose * lose;
+    m_sumOfSquares += f * f;
+
+    m_rms = sqrt(m_sumOfSquares / fill);
+//    cerr << "rms = " << m_rms << " (from " << fill << " samples of " << m_histlen << ", latest " << f << ")" << endl;
+}
+
+const LADSPA_Descriptor *
+ladspa_descriptor(unsigned long ix)
+{
+    return FlattenDynamics::getDescriptor(ix);
+}
+