Video.h

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#pragma once
#include "AudioTools/CoreAudio/AudioOutput.h"
#include "AudioTools/CoreAudio/Buffers.h"
#include "stdint.h"
 
namespace audio_tools {
 
class VideoOutput {
 public:
  virtual void beginFrame(size_t size) = 0;
  virtual size_t write(const uint8_t *data, size_t len) = 0;
  virtual uint32_t endFrame() = 0;
};
 
class VideoAudioSync {
 public:
  virtual void writeAudio(Print *out, uint8_t *data, size_t size) {
    out->write(data, size);
  }
 
  virtual void delayVideoFrame(int32_t microsecondsPerFrame,
                               uint32_t time_used_ms) {
    uint32_t delay_ms = microsecondsPerFrame / 1000;
    delay(delay_ms);
  }
};
 
class VideoAudioBufferedSync : public VideoAudioSync {
 public:
  VideoAudioBufferedSync(int bufferSize, int correctionMs) {
    ring_buffer.resize(bufferSize);
    correction_ms = correctionMs;
  }
 
  void writeAudio(Print *out, uint8_t *data, size_t size) {
    p_out = out;
    if (ring_buffer.availableForWrite() < size) {
      int bytes_to_play = size - ring_buffer.availableForWrite();
      uint8_t audio[bytes_to_play];
      ring_buffer.readArray(audio, bytes_to_play);
      p_out->write(audio, bytes_to_play);
    }
    size_t written = ring_buffer.writeArray(data, size);
    assert(written = size);
  }
 
  void delayVideoFrame(int32_t microsecondsPerFrame, uint32_t time_used_ms) {
    uint32_t delay_ms = microsecondsPerFrame / 1000;
    uint64_t timeout = millis() + delay_ms + correction_ms;
    uint8_t audio[8];
    // output audio
    while (millis() < timeout) {
      ring_buffer.readArray(audio, 8);
      p_out->write(audio, 8);
    }
  }
 
 protected:
  RingBuffer<uint8_t> ring_buffer{0};
  Print *p_out = nullptr;
  int correction_ms = 0;
};
 
}  // namespace audio_tools