audio_decoder.h

Go to the documentation of this file.

#pragma once
 
#ifdef USE_ESP32
 
#include "audio.h"
#include "audio_transfer_buffer.h"
 
#include "esphome/core/defines.h"
#include "esphome/core/helpers.h"
#include "esphome/core/ring_buffer.h"
 
#ifdef USE_SPEAKER
#include "esphome/components/speaker/speaker.h"
#endif
 
#include "esp_err.h"
 
// esp-audio-libs
#ifdef USE_AUDIO_FLAC_SUPPORT
#include <flac_decoder.h>
#endif
#ifdef USE_AUDIO_MP3_SUPPORT
#include <mp3_decoder.h>
#endif
#include <wav_decoder.h>
 
namespace esphome {
namespace audio {
 
enum class AudioDecoderState : uint8_t {
  DECODING = 0,  // More data is available to decode
  FINISHED,      // All file data has been decoded and transferred
  FAILED,        // Encountered an error
};
 
// Only used within the AudioDecoder class; conveys the state of the particular file type decoder
enum class FileDecoderState : uint8_t {
  MORE_TO_PROCESS,     // Successsfully read a file chunk and more data is available to decode
  IDLE,                // Not enough data to decode, waiting for more to be transferred
  POTENTIALLY_FAILED,  // Decoder encountered a potentially recoverable error if more file data is available
  FAILED,              // Decoder encoutnered an uncrecoverable error
  END_OF_FILE,         // The specific file decoder knows its the end of the file
};
 
class AudioDecoder {
  /*
   * @brief Class that facilitates decoding an audio file.
   * The audio file is read from a ring buffer source, decoded, and sent to an audio sink (ring buffer or speaker
   * component).
   * Supports wav, flac, and mp3 formats.
   */
 public:
  AudioDecoder(size_t input_buffer_size, size_t output_buffer_size);
 
  ~AudioDecoder();
 
  esp_err_t add_source(std::weak_ptr<RingBuffer> &input_ring_buffer);
 
  esp_err_t add_sink(std::weak_ptr<RingBuffer> &output_ring_buffer);
 
#ifdef USE_SPEAKER
  esp_err_t add_sink(speaker::Speaker *speaker);
#endif
 
  esp_err_t start(AudioFileType audio_file_type);
 
  AudioDecoderState decode(bool stop_gracefully);
 
  const optional<audio::AudioStreamInfo> &get_audio_stream_info() const { return this->audio_stream_info_; }
 
  uint32_t get_playback_ms() const { return this->playback_ms_; }
 
  void set_pause_output_state(bool pause_state) { this->pause_output_ = pause_state; }
 
 protected:
  std::unique_ptr<esp_audio_libs::wav_decoder::WAVDecoder> wav_decoder_;
#ifdef USE_AUDIO_FLAC_SUPPORT
  FileDecoderState decode_flac_();
  std::unique_ptr<esp_audio_libs::flac::FLACDecoder> flac_decoder_;
#endif
#ifdef USE_AUDIO_MP3_SUPPORT
  FileDecoderState decode_mp3_();
  esp_audio_libs::helix_decoder::HMP3Decoder mp3_decoder_;
#endif
  FileDecoderState decode_wav_();
 
  std::unique_ptr<AudioSourceTransferBuffer> input_transfer_buffer_;
  std::unique_ptr<AudioSinkTransferBuffer> output_transfer_buffer_;
 
  AudioFileType audio_file_type_{AudioFileType::NONE};
  optional<AudioStreamInfo> audio_stream_info_{};
 
  size_t free_buffer_required_{0};
  size_t wav_bytes_left_{0};
 
  uint32_t potentially_failed_count_{0};
  bool end_of_file_{false};
  bool wav_has_known_end_{false};
 
  bool pause_output_{false};
 
  uint32_t accumulated_frames_written_{0};
  uint32_t playback_ms_{0};
};
}  // namespace audio
}  // namespace esphome
 
#endif