Rack/plugins/community/repos/squinkylabs-plug1/test/testAnalyzer.cpp

#include <assert.h>
#include <vector>


#include "Analyzer.h"
#include "asserts.h"
#include "AudioMath.h"

#include "FFTData.h"
#include "SinOscillator.h"
#include "MeasureTime.h"


static void ana1()
{
    FFTDataCpx x(2);
    x.set(0, cpx(float(AudioMath::gainFromDb(0)), 0));

    auto data = Analyzer::getFeatures(x, 3, 44100, -100);
    assert(data.size() == 1);
    assertClose(data[0].gainDb, 0, .0001);
    assertClose(data[0].freq, 0, .0001);
}


// test  Analyzer::getFeatures with two bins of 
// very different gains
static void ana2()
{
    FFTDataCpx x(4);
    x.set(0, cpx(float(AudioMath::gainFromDb(0)), 0));
    x.set(1, cpx(float(AudioMath::gainFromDb(10)), 0));

    auto data = Analyzer::getFeatures(x, 3, 44100, -100);
    assert(data.size() == 2);
    assertClose(data[0].gainDb, 0, .0001);
    assertClose(data[0].freq, 0, .0001);

    assertClose(data[1].gainDb, 10, .0001);

    // bin 1 (last bin) is sr/2 ... sr
    assertClose(data[1].freq, 44100 / 4, .0001);
}

static void ana3()
{
    const int size = 1024;
    std::vector<float> buffer(size);
    Analyzer::generateSweep(44100., buffer.data(), size, 20, 20000);

    auto minMax = AudioMath::getMinMax(buffer.data(), size);
    assertClose(minMax.first, -1, .01);
    assertClose(minMax.second, 1, .01);
}

static void ana7()
{
    const int size = 64;
    FFTDataCpx x(size);
    std::function<float(float)> unity = [](float x) {
        return x;
    };
    Analyzer::getFreqResponse(x, unity);

    for (int i = 0; i < size / 2; ++i) {
        assertClose(std::abs(x.get(i)), 1, .0001);
    }
}


// test that we get a good spectrum from synchronous sin
static void testSyncSin()
{
    float desiredFreq = 500.0f;
    int numSamples = 16 * 1024;
    const float sampleRate = 44100.0f;
    const double actualFreq = Analyzer::makeEvenPeriod(desiredFreq, sampleRate, numSamples);

    SinOscillatorParams<float> sinParams;
    SinOscillatorState<float> sinState;
    SinOscillator<float, false>::setFrequency(sinParams, float(actualFreq / sampleRate));

    FFTDataCpx spectrum(numSamples);
    Analyzer::getSpectrum(spectrum, false, [&sinState, &sinParams]() {
        return SinOscillator<float, false>::run(sinState, sinParams);
        });

    Analyzer::assertSingleFreq(spectrum, float(actualFreq), sampleRate);
}



void testAnalyzer()
{
    ana1();
    ana2();
    ana3();
    ana7();
    testSyncSin();
}