RMSData.hpp

#pragma once
#include <Process/TimeValue.hpp>
 
#include <Media/AudioArray.hpp>
 
#include <ossia/detail/span.hpp>
 
#include <QBuffer>
#include <QFile>
 
namespace Media
{
 
using rms_sample_t = int16_t;
struct RMSData : public QObject
{
  W_OBJECT(RMSData)
public:
  struct Header
  {
    uint32_t sampleRate{};
    uint32_t bufferSize{};
    uint32_t channels{};
    uint32_t padding{};
  };
 
  RMSData();
 
  void load(QString abspath, int channels, int rate, TimeVal duration);
  bool exists() const;
 
  // deinterleaved
  void decode(const std::vector<tcb::span<const ossia::audio_sample>>& audio);
  void decodeLast(const std::vector<tcb::span<const ossia::audio_sample>>& audio);
 
  // interleaved
  void decode(ossia::drwav_handle& audio);
  double sampleRateRatio(double expectedRate) const noexcept;
 
  ossia::small_vector<float, 8>
  frame(int64_t start_sample, int64_t end_sample) const noexcept;
 
  int64_t frames_count = 0;
  int64_t samples_count = 0;
 
  Header* header_ptr() const noexcept { return header; }
  rms_sample_t* data_ptr() const noexcept { return data; }
 
  void newData() W_SIGNAL(newData);
  void finishedDecoding() W_SIGNAL(finishedDecoding);
 
private:
  rms_sample_t computeChannelRMS(
      tcb::span<const ossia::audio_sample> chan, int64_t start_idx, int64_t buffer_size);
  void computeRMS(
      const std::vector<tcb::span<const ossia::audio_sample>>& audio, int buffer_size);
  void computeLastRMS(
      const std::vector<tcb::span<const ossia::audio_sample>>& audio, int buffer_size);
  void
  computeChannelRMS(ossia::drwav_handle& wav, rms_sample_t* bytes, int64_t buffer_size);
 
  QFile m_file;
  bool m_exists{false};
 
  Header* header{};
  rms_sample_t* data{};
 
  QByteArray m_ramData;
  QBuffer m_ramBuffer;
};
 
}