CustomAudioStream.cpp

#include "CustomAudioStream.h"

CustomAudioStream::CustomAudioStream() {
    initialize(channelCount, sampleRate);
}

bool CustomAudioStream::loadFromFile(const std::string& filename) {
    sf::SoundBuffer buffer;
    if (!buffer.loadFromFile(filename)) {
        std::cerr << "Failed to load file: " << filename << std::endl;
        return false;
    }

    samples.assign(buffer.getSamples(), buffer.getSamples() + buffer.getSampleCount());
    sampleRate = buffer.getSampleRate();
    channelCount = buffer.getChannelCount();
    initialize(channelCount, sampleRate);

    dt = 1.0f / static_cast<float>(sampleRate);
    RC_low = 1.0f / (2 * 3.1416f * lowCutoff);
    RC_high = 1.0f / (2 * 3.1416f * highCutoff);
    alphaLow = dt / (RC_low + dt);
    alphaHigh = RC_high / (RC_high + dt);

    currentSample = 0;
    return true;
}

void CustomAudioStream::setVolume(float vol) {
    volume = vol;
}

void CustomAudioStream::setEqualizerGains(float low, float mid, float high) {
    lowGain = low;
    midGain = mid;
    highGain = high;
}

bool CustomAudioStream::onGetData(Chunk& data) {
    const std::size_t chunkSize = 4096;
    if (currentSample >= samples.size())
        return false;

    std::size_t endSample = std::min(currentSample + chunkSize, samples.size());
    buffer.resize(endSample - currentSample);

    for (std::size_t i = 0; i < buffer.size(); ++i) {
        buffer[i] = applyEqualizer(samples[currentSample + i]);
    }

    data.samples = buffer.data();
    data.sampleCount = buffer.size();
    currentSample = endSample;

    return true;
}

void CustomAudioStream::onSeek(sf::Time timeOffset) {
    currentSample = static_cast<std::size_t>(timeOffset.asSeconds() * sampleRate * channelCount);
}

sf::Int16 CustomAudioStream::applyEqualizer(sf::Int16 sample) {

    //Limiter
    float totalGain = lowGain + midGain + highGain;

    if (totalGain > 3.0f) {
        float scale = 3.0f / totalGain;
        lowGain *= scale;
        midGain *= scale;
        highGain *= scale;
    }

    float s = static_cast<float>(sample);

    // Low-pass filter (íèçêèå ÷àñòîòû)
    lowY = lowY + alphaLow * (s - lowY);
    float low = lowY;

    // High-pass filter (âûñîêèå ÷àñòîòû)

    highY = alphaHigh * (highY + s - prevInput);
    prevInput = s;
    float high = highY;

    // Middle = îðèãèíàë - (low + high)
    float mid = s - (low + high);

    // Óñèëåíèå êàæäîé ïîëîñû
    float result = low * lowGain + mid * midGain + high * highGain;

    result *= volume / 100.f;

    return static_cast<sf::Int16>(std::clamp(result, -32768.f, 32767.f));
}